25-hydroxyvitamin-d-2 and Vitamin-D-Deficiency

The role of vitamin D supplementation as a treatment for COVID-19 has been a subject of considerable discussion. A thorough understanding of the current evidence regarding the effectiveness and safety of vitamin D supplementation for COVID-19 based on randomised controlled trials is required.. To assess whether vitamin D supplementation is effective and safe for the treatment of COVID-19 in comparison to an active comparator, placebo, or standard of care alone, and to maintain the currency of the evidence, using a living systematic review approach.. We searched the Cochrane COVID-19 Study Register, Web of Science and the WHO COVID-19 Global literature on coronavirus disease to identify completed and ongoing studies without language restrictions to 11 March 2021.. We followed standard Cochrane methodology. We included randomised controlled trials (RCTs) evaluating vitamin D supplementation for people with COVID-19, irrespective of disease severity, age, gender or ethnicity. We excluded studies investigating preventive effects, or studies including populations with other coronavirus diseases (severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS)).. We followed standard Cochrane methodology. To assess bias in included studies, we used the Cochrane risk of bias tool (ROB 2) for RCTs. We rated the certainty of evidence using the GRADE approach for the following prioritised outcome categories: individuals with moderate or severe COVID-19: all-cause mortality, clinical status, quality of life, adverse events, serious adverse events, and for individuals with asymptomatic or mild disease: all-cause mortality, development of severe clinical COVID-19 symptoms, quality of life, adverse events, serious adverse events.. We identified three RCTs with 356 participants, of whom 183 received vitamin D. In accordance with the World Health Organization (WHO) clinical progression scale, two studies investigated participants with moderate or severe disease, and one study individuals with mild or asymptomatic disease. The control groups consisted of placebo treatment or standard of care alone. Effectiveness of vitamin D supplementation for people with COVID-19 and moderate to severe disease We included two studies with 313 participants. Due to substantial clinical and methodological diversity of both studies, we were not able to pool data. Vitamin D status was unknown in one study, whereas the other study reported data for vitamin D deficient participants. One study administered multiple doses of oral calcifediol at days 1, 3 and 7,  whereas the other study gave a single high dose of oral cholecalciferol at baseline. We assessed one study with low risk of bias for effectiveness outcomes, and the other with some concerns about randomisation and selective reporting. All-cause mortality at hospital discharge (313 participants) We found two studies reporting data for this outcome. One study reported no deaths when treated with vitamin D out of 50 participants, compared to two deaths out of 26 participants in the control group (Risk ratio (RR) 0.11, 95% confidence interval (CI) 0.01 to 2.13). The other study reported nine deaths out of 119 individuals in the vitamin D group, whereas six participants out of 118 died in the placebo group (RR 1.49, 95% CI 0.55 to 4.04]. We are very uncertain whether vitamin D has an effect on all-cause mortality at hospital discharge (very low-certainty evidence). Clinical status assessed by the need for invasive mechanical ventilation (237 participants) We found one study reporting data for this outcome. Nine out of 119 participants needed invasive mechanical ventilation when treated with vitamin D, compared to 17 out of 118 participants in the placebo group (RR 0.52, 95% CI 0.24 to 1.13). Vitamin D supplementation may decrease need for invasive mechanical ventilation, but the evidence is uncertain (low-certainty evidence). Quality of life We did not find data for quality of life. Safety of vitamin D supplementation for people with COVID-19 and moderate to severe disease We did not include data from one study, because assessment of serious adverse events was not described and we are concerned that data might have been inconsistently measured. This study. There is currently insufficient evidence to determine the benefits and harms of vitamin D supplementation as a treatment of COVID-19. The evidence for the effectiveness of vitamin D supplementation for the treatment of COVID-19 is very uncertain. Moreover, we found only limited safety information, and were concerned about consistency in measurement and recording of these outcomes. There was substantial clinical and methodological heterogeneity of included studies, mainly because of different supplementation strategies, formulations, vitamin D status of participants, and reported outcomes. There is an urgent need for well-designed and adequately powered randomised controlled trials (RCTs) with an appropriate randomisation procedure, comparability of study arms and preferably double-blinding. We identified 21 ongoing and three completed studies without published results, which indicates that these needs will be addressed and that our findings are subject to change in the future. Due to the living approach of this work, we will update the review periodically.

Topics: 25-Hydroxyvitamin D 2; Adrenal Cortex Hormones; Adult; Azithromycin; Bias; Calcifediol; Cause of Death; Ceftriaxone; Cholecalciferol; COVID-19; COVID-19 Drug Treatment; Drug Therapy, Combination; Humans; Hydroxychloroquine; Middle Aged; Quality of Life; Randomized Controlled Trials as Topic; Vitamin D Deficiency; Vitamins

Vitamin D deficiency is common worldwide, contributing to nutritional rickets and osteomalacia which have a major impact on health, growth, and development of infants, children and adolescents. Vitamin D levels are low in breast milk and exclusively breastfed infants are at risk of vitamin D insufficiency or deficiency.. To determine the effect of vitamin D supplementation given to infants, or lactating mothers, on vitamin D deficiency, bone density and growth in healthy term breastfed infants.. We used the standard search strategy of Cochrane Neonatal to 29 May 2020 supplemented by searches of clinical trials databases, conference proceedings, and citations.. Randomised controlled trials (RCTs) and quasi-RCTs in breastfeeding mother-infant pairs comparing vitamin D supplementation given to infants or lactating mothers compared to placebo or no intervention, or sunlight, or that compare vitamin D supplementation of infants to supplementation of mothers.. Two review authors assessed trial eligibility and risk of bias and independently extracted data. We used the GRADE approach to assess the certainty of evidence.. We included 19 studies with 2837 mother-infant pairs assessing vitamin D given to infants (nine studies), to lactating mothers (eight studies), and to infants versus lactating mothers (six studies). No studies compared vitamin D given to infants versus periods of infant sun exposure. Vitamin D supplementation given to infants: vitamin D at 400 IU/day may increase 25-OH vitamin D levels (MD 22.63 nmol/L, 95% CI 17.05 to 28.21; participants = 334; studies = 6; low-certainty) and may reduce the incidence of vitamin D insufficiency (25-OH vitamin D < 50 nmol/L) (RR 0.57, 95% CI 0.41 to 0.80; participants = 274; studies = 4; low-certainty). However, there was insufficient evidence to determine if vitamin D given to the infant reduces the risk of vitamin D deficiency (25-OH vitamin D < 30 nmol/L) up till six months of age (RR 0.41, 95% CI 0.16 to 1.05; participants = 122; studies = 2), affects bone mineral content (BMC), or the incidence of biochemical or radiological rickets (all very-low certainty). We are uncertain about adverse effects including hypercalcaemia. There were no studies of higher doses of infant vitamin D (> 400 IU/day) compared to placebo. Vitamin D supplementation given to lactating mothers: vitamin D supplementation given to lactating mothers may increase infant 25-OH vitamin D levels (MD 24.60 nmol/L, 95% CI 21.59 to 27.60; participants = 597; studies = 7; low-certainty), may reduce the incidences of vitamin D insufficiency (RR 0.47, 95% CI 0.39 to 0.57; participants = 512; studies = 5; low-certainty), vitamin D deficiency (RR 0.15, 95% CI 0.09 to 0.24; participants = 512; studies = 5; low-certainty) and biochemical rickets (RR 0.06, 95% CI 0.01 to 0.44; participants = 229; studies = 2; low-certainty). The two studies that reported biochemical rickets used maternal dosages of oral D3 60,000 IU/day for 10 days and oral D3 60,000 IU postpartum and at 6, 10, and 14 weeks. However, infant BMC was not reported and there was insufficient evidence to determine if maternal supplementation has an effect on radiological rickets (RR 0.76, 95% CI 0.18 to 3.31; participants = 536; studies = 3; very low-certainty). All studies of maternal supplementation enrolled populations at high risk of vitamin D deficiency. We are uncertain of the effects of maternal supplementation on infant growth and adverse effects including hypercalcaemia. Vitamin D supplementation given to infants compared with supplementation given to lactating mothers: infant vitamin D suppl. For breastfed infants, vitamin D supplementation 400 IU/day for up to six months increases 25-OH vitamin D levels and reduces vitamin D insufficiency, but there was insufficient evidence to assess its effect on vitamin D deficiency and bone health. For higher-risk infants who are breastfeeding, maternal vitamin D supplementation reduces vitamin D insufficiency and vitamin D deficiency, but there was insufficient evidence to determine an effect on bone health. In populations at higher risk of vitamin D deficiency, vitamin D supplementation of infants led to greater increases in infant 25-OH vitamin D levels, reductions in vitamin D insufficiency and vitamin D deficiency compared to supplementation of lactating mothers. However, the evidence is very uncertain for markers of bone health. Maternal higher dose supplementation (≥ 4000 IU/day) produced similar infant 25-OH vitamin D levels as infant supplementation of 400 IU/day. The certainty of evidence was graded as low to very low for all outcomes.

Topics: 25-Hydroxyvitamin D 2; Bone and Bones; Bone Density; Breast Feeding; Female; Humans; Hypercalcemia; Infant; Lactation; Mothers; Randomized Controlled Trials as Topic; Rickets; Term Birth; Vitamin D; Vitamin D Deficiency; Vitamins

The optimal concentration of individual vitamin D intake for preventing bladder cancer has not, to our knowledge, been defined. To evaluate the comparative efficacy of different serum 25-hydroxyvitamin D concentrations in preventing bladder cancer, we conducted a systematic search of the literature published up to April 2015.. We applied a pairwise meta-analysis to estimate direct evidence from intervention-control studies and a network meta-analysis within a Bayesian framework to combine direct and indirect evidence. Moreover, a dose-response curve was utilized to predict the optimal median serum 25-hydroxyvitamin D concentration based on the odds ratio (OR) for each quintile concentration.. Seven studies of a total of 90757 participants, including 2509 bladder cancer patients, were included. Two prospective cohort studies with 57 591 participants and 494 bladder cancer patients, and five case-control studies with 33 166 participants and 2264 bladder cancer patients. From the network meta-analysis, we observed that sufficient serum 25-hydroxyvitamin D concentrations (>75 nmol/L) were superior to all other 25-hydroxyvitamin D concentrations in decreasing the risk of bladder cancer: OR = 0.68 and 95% credible interval (CrI) 0.52 to 0.87 compared with severely deficient concentrations (<25 nmol/L); OR = 0.65 and 95% CrI 0.49 to 0.86 compared with moderately deficient concentrations (25-37.5 nmol/L); OR = 0.61 and 95% CrI 0.47 to 0.80 compared with slightly deficient concentrations (37.5-50 nmol/L); and OR = 0.65 and 95% CrI 0.48 to 0.85 compared with insufficient concentrations (50-75 nmol/L). In addition, we noted a roughly inverse correlation between bladder cancer risk and 25-hydroxyvitamin D concentrations (R(2) = 0.98, P = 0.007).. Ensuring sufficient serum 25-hydroxyvitamin D concentrations might play an important role in decreasing the risk of bladder cancer. The serum 25-hydroxyvitamin D concentration ≥74 nmol/L was associated with a 60% lower risk of bladder cancer incidence.

Topics: 25-Hydroxyvitamin D 2; Anticarcinogenic Agents; Bayes Theorem; Calcifediol; Evidence-Based Medicine; Humans; Network Meta-Analysis; Nutritional Status; Risk; Severity of Illness Index; Urinary Bladder Neoplasms; Vitamin D; Vitamin D Deficiency

Inconsistent findings have been published regarding vitamin D status among patients with Crohn's disease (CD) and the association with disease severity. We aimed to perform a meta-analysis evaluating serum 25-hydroxy vitamin D and 1,25 dehydroxyvitamin D among CD patients compared with healthy and non-healthy controls, the prevalence of vitamin D deficiency, and the association with disease.. We searched MEDLINE, SCOPUS, EMBASE, and Google Scholar up to March 2015 for observational studies assessing serum vitamin D levels in CD patients. A total of 63 studies were included in the following four meta-analyses: 1) a meta-analysis on the mean difference of 25(OH)D levels in CD patients compared with healthy (number of studies = 27) and non-healthy (n = 25) controls; 2) a meta-analysis on the mean difference of 1,25(OH)2 D3 levels in CD patients compared with healthy (n = 7) and non-healthy (n = 8) controls; 3) a meta-analysis on the prevalence of vitamin D deficiency (n = 34); 4) a meta-analysis on the correlation coefficients between vitamin D status severity of CD (n = 6). Subgroup analysis and meta-regression were used to discover possible sources of between-study heterogeneity.. It was found that CD patients had lower levels of 25(OH)D compared with healthy (-3.99 ng/mL; 95% confidence interval [CI]: -5.91 to -2.08) but not non-healthy controls (-1.07 ng/mL; 95% CI: -2.84 to 0.70). There was also no significant mean difference for 1,25(OH)2 D3 for both healthy and non-healthy controls. Meta-analysis on the prevalence of vitamin D deficiency showed an overall prevalence of 57.7% (95% CI: 0.502-0.649). An inverse association was observed between serum vitamin D and severity of CD (-0.36; 95% CI: -0.48 to -0.24). Meta-regression showed that mean levels of 25(OH)D were decreased 0.09 for each unit change of latitude among CD patients compared with healthy controls (B = -0.09, P = 0.004, I(2) residual = 86.08%).. We found that patients with Crohn's disease had lower serum 25(OH)D concentrations compared with their healthy counterparts, and more than half of them have hypovitaminosis D. Moreover, there was an inverse correlation between circulating 25(OH)D concentrations and severity of Crohn's disease.

Topics: 25-Hydroxyvitamin D 2; Adult; Child; Crohn Disease; Evidence-Based Medicine; Global Health; Humans; Nutritional Status; Observational Studies as Topic; Prevalence; Severity of Illness Index; Sunlight; Vitamin D Deficiency

Between 1987 and the date of the present issue, 10 reports have been published on the prevalence of the vitamin D deficit in Argentina. These studies were done investigating new born babies, children, adolescents, and healthy and institutionalized adults, living in southern, middle or northern cities of Argentina. The weighed prevalence of vitamin D deficit in those reports was 43.3% (436/1007). This figure may be lower than reality because it is not known whether the stratification (age and location of residence) of the sum of samples agree with that of the national population. Taking into account the obvious difficulties in carrying out such a research two areas for further research are suggested: a) an investigation on the solar exposure in summer needed to obviate (or not) the oral supplementation of vitamin D in winter, b) to determine the success of the schema of administration taking into account the current controversy between dose and optimum plasma levels of 25(HO)D3. In both instances, the end point should include some of the physiological functions alluded to in this editorial.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Argentina; Child; Child, Preschool; Female; Humans; Infant; Infant, Newborn; Male; Middle Aged; Prevalence; Reference Values; Seasons; Vitamin D Deficiency; Young Adult

Supplementation with vitamin D has received attention as a potential cardioprotective strategy. Biologically plausible mechanisms have been proposed to link vitamin D to coronary heart disease (CHD) prevention, and observational studies suggest an inverse association between serum 25-hydroxyvitamin D (25OHD) concentrations and CHD. Few randomized clinical trials of vitamin D supplementation and CHD have been conducted, however, and no trial with CHD as the primary prespecified outcome has been completed.. A search was conducted in PubMed to find prospective studies of the use of vitamin D supplementation and its relationship to cardiovascular risk factors (RFs) and/or cardiovascular disease (CVD). The exact search query was: ((vitamin D supplement*[Title/Abstract]) AND cardiovascular [Title/Abstract]) AND prospective [Title/Abstract]. This query yielded 42 results. "Randomized Controlled Trial" (article type) was used as a filter in a subsequent query with the same search terms. We review the evidence that vitamin D supplementation modifies coronary RFs, such as blood pressure, lipids, glucose tolerance, and/or affects the development of clinical CHD events. We address potential sources of confounding in observational epidemiologic studies of the relationship between serum 25OHD and CHD. We also address laboratory assay issues relevant to the reliable measurement of 25OHD.. Most vitamin D supplementation trials have not demonstrated improvement in CVD, but they have tested relatively low vitamin D doses. Thus, the evidence remains inconclusive, highlighting the need for rigorous randomized trials of higher vitamin D doses with cardiovascular events as prespecified outcomes. While we await the results of ongoing trials, the recommended dietary allowances from the Institute of Medicine remain the best guidepost for nutritional requirements.

Topics: 25-Hydroxyvitamin D 2; Coronary Artery Disease; Dietary Supplements; Homeostasis; Humans; Randomized Controlled Trials as Topic; Risk; Vitamin D; Vitamin D Deficiency; Vitamins

This systematic review and meta-analysis was performed on the relationship of serum 25-hydroxy-vitamin D [25(OH)D] and lipid profile in the pediatric age group. Electronic search was conducted in international databases. Our search yielded to 3213 articles, with initial searching of title and abstracts, 3192 of them were excluded and 21 remained. A meta-analysis of 17 cross-sectional studies, including 25 394 subjects, was conducted according to Strobe guideline. We found an inverse weak significant association between 25(OH)D and triglycerides (r = -0.135, CI; -0.243, -0.025), total cholesterol (r = -0.086, CI; -0.0205, 0.035) and LDL-C (r = -0.025, CI; -0.22, 0.17), and direct association with HDL-C (r = 0.156, CI; -0.021, 0.324). In the pooled analysis, we used a random effects model as the heterogeneity between studies was significant (I²= 97.04%, p < 0.001 for triglycerides; I²= 96.09%, p < 0.001 for total cholesterol; I²= 96.14%, p < 0.001 for LDL-C; I²= 99%, p < 0.001 for HDL-C). This study indicates that higher serum 25(OH)D is related to a more favorable lipid profile in the pediatric age group.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Child; Cross-Sectional Studies; Humans; Hyperlipidemias; Lipids; Nutritional Status; Vitamin D Deficiency

This article presents an overview of the most recent scientific evidence of the role of maternal vitamin D on pregnancy outcomes, with a particular emphasis on those articles in the English-language literature published between 1 January 2013 and 1 July 2014 in PubMed.. Low levels of vitamin D status, as measured by 25-hydroxyvitamin D [25(OH)D], are common in pregnant women. Meta-analysis of observational studies has demonstrated positive associations between vitamin D status and adverse pregnancy outcomes such as preeclampsia, gestational diabetes mellitus, preterm birth and small-for-gestational age. There was heterogeneity among studies in terms of design, population, geographic location, definitions of exposure and outcome, gestational age at sampling, confounding factors and approach to analyses. Randomized controlled trials (RCTs) indicate that vitamin D supplementation during pregnancy optimizes maternal and neonatal vitamin D status.. Recent evidence supports that low maternal vitamin D status is associated with an increased risk of adverse pregnancy outcomes. Interventional studies demonstrate that vitamin D supplementation during pregnancy optimizes maternal and neonatal vitamin D status. Large, well designed, multicentre RCTs are required to determine whether vitamin D supplementation in pregnant women with low vitamin D status reduces the risk of adverse pregnancy outcomes.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Diabetes, Gestational; Dietary Supplements; Evidence-Based Medicine; Female; Fetal Growth Retardation; Global Health; Humans; Maternal Nutritional Physiological Phenomena; Nutritional Status; Pre-Eclampsia; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Premature Birth; Risk Factors; Vitamin D; Vitamin D Deficiency

There is no doubt that vitamin D must be activated to the hormonal form 1,25-dihydroxyvitamin D to achieve full biological activity or that many tissues participate in this activation process-be it endocrine or autocrine. We believe that not only is 25-hydroxyvitamin D important to tissue delivery for this activation process, but also that intact vitamin D has a pivotal role in this process.. In this review, evidence on the vitamin D endocrine/autocrine system is presented and discussed in relation to vitamin D-binding protein affinity, circulating half-lives, and enzymatic transformations of vitamin D metabolites, and how these affect biological action in any given tissue.. Circulating vitamin D, the parent compound, likely plays an important physiological role with respect to the vitamin D endocrine/autocrine system, as a substrate in many tissues, not originally thought to be important. Based on emerging data from the laboratory, clinical trials, and data on circulating 25-hydroxyvitamin D amassed during many decades, it is likely that for the optimal functioning of these systems, significant vitamin D should be available on a daily basis to ensure stable circulating concentrations, implying that variation in vitamin D dosing schedules could have profound effects on the outcomes of clinical trials because of the short circulating half-life of intact vitamin D.

Topics: 25-Hydroxyvitamin D 2; Animals; Autocrine Communication; Calcifediol; Calcitriol; Dietary Supplements; Endocrine System; Endocrine System Diseases; Ergocalciferols; Humans; Vitamin D; Vitamin D Deficiency

To evaluate the association between 25-hydroxyvitamin D [25(OH)D] and sustained virological response (SVR) in hepatitis C virus (HCV) infected individuals.. Relevant studies were identified by systematically searching MEDLINE databases up to March 2012 and abstracts of the European and American Congress of Hepatology conducted in 2011. Studies must provide information on SVR and the levels of 25(OH)D₃ and/or 25(OH)D₂ [henceforth referred to as 25(OH)D] in sera samples from HCV infected individuals. The inclusion criteria were: clinical studies that included HCV infected patients aged older than 18 years regardless of HCV genotype or ethnic group; provided information on SVR rates; and were reported in the English language as full papers. Due to the heterogeneity of studies in categorizing serum vitamin D levels, a cut-off value of 30 ng/mL of serum 25(OH)D was used. Heterogeneity was assessed using I² statistics. The summary odds ratios with their corresponding 95%CI were calculated based on a random-effects model.. Overall, 11 studies (8 observational and 3 interventional) involving 1575 individuals were included and 1117 HCV infected individuals (71%) showed low vitamin D levels. Most of the studies included mono-infected HCV individuals with the mean age ranging from 38 to 56 years. Four studies were conducted in human immunodeficiency virus/HCV infected individuals. Regarding vitamin D measurement, most of the studies employed radioimmunoassays (n = 5) followed by chemiluminescence (n = 4) and just one study employed high performance/pressure liquid chromatography (HPLC). Basal vitamin D levels varied from 17 to 43 ng/mL in the studies selected, and most of the HCV infected individuals had genotype 1 (1068/1575) with mean viral load varying from log 4.5-5.9 UI/mL. With regard to HCV treatment, most of the studies (n = 8) included HCV individuals without previous treatment, where the pooled SVR rate was 46.4%. High rates of SVR were observed in HCV individuals with vitamin D levels above 30 ng/mL (OR = 1.57; 95%CI: 1.12-2.2) and those supplemented with vitamin D (OR = 4.59; 95%CI: 1.67-12.63) regardless of genotype.. Our results demonstrated high prevalence of vitamin D deficiency and high SVR in individuals with higher serum vitamin D levels or receiving vitamin D supplementation.

Topics: 25-Hydroxyvitamin D 2; Adult; Antiviral Agents; Biomarkers; Calcifediol; Chi-Square Distribution; Dietary Supplements; Hepatitis C; Humans; Middle Aged; Odds Ratio; Prevalence; Risk Factors; Treatment Outcome; Viral Load; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Adult; Affect; Brain; Depressive Disorder; Humans; Vitamin D; Vitamin D Deficiency

The incidence of vitamin D deficiency is rising worldwide, yet in the vast majority of patients, the condition remains undiagnosed and untreated. Current evidence overwhelmingly indicates that supplemental doses greater than 800 IU/day have beneficial effects on the musculoskeletal system, improving skeletal homeostasis, thus leading to fewer falls and fractures. Evidence is also accumulating on the beneficial effects of vitamin D on extraskeletal systems, such as improving immune health, autoimmune disorders, cancer, neuromodulation, diabetes, and metabolic syndrome. The cause-effect relationship of vitamin D deficiency with increasing incidences of nonskeletal disorders is being investigated. Published reports support the definition of sufficiency, serum levels of 25-hydroxyvitamin D [25(OH)D] greater than 30 ng/mL (75 nmol/L). To achieve this, most people need vitamin D supplementation ranging from 600 to 2000 IU/day; consumption up to of 5000 international units (IU) per day of vitamin D is reported as safe. Although light-skinned individuals need 1000 IU/day of vitamin D, elderly and dark-skinned individuals are likely to need approximately 2000 IU/day to maintain serum 25(OH)D levels greater than 30 ng/mL. Other vulnerable patients, such as the obese, those who have undergone bariatric surgery, and those with gastrointestinal malabsorption syndromes, may require higher doses of vitamin D to maintain normal serum levels and be healthy.

Topics: 25-Hydroxyvitamin D 2; Bone Density; Bone Density Conservation Agents; Humans; Nutrition Policy; Prevalence; Vitamin D; Vitamin D Deficiency

Measurement of 25-hydroxyvitamin D (25-OHD) is widely used for assessing vitamin D status. There has been a dramatic increase in 25-OHD requests over recent years prompting many laboratories to consider the use of automated immunoassays. To achieve higher throughput, these methods have abandoned the traditional solvent extraction of samples and are therefore more prone to non-specific interference. The Vitamin D External Quality Assessment Scheme (DEQAS) has revealed method-related differences in 25-OHD results, raising concerns about the comparability and accuracy of different assays. This paper highlights some of the pre-analytical, analytical and post-analytical issues which may influence the accuracy of 25-OHD assays and interpretation of results. Recent attention has focused on reconciling the relatively high results given by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to those of the DiaSorin radioimmunoassay (RIA) on which clinical decision points have previously been based. Data is presented on 20 DEQAS samples which were analysed by an LC-MS/MS assay developed as a candidate reference measurement procedure by the US National Institute of Standards and Technology (NIST). The NIST results were on average 11.2% lower than those given by routine LC-MS/MS methods. If confirmed, these results suggest that most routine LC-MS/MS assays are perhaps overestimating 25-OHD by failing to resolve a molecule having the same mass as 25-OHD(3) and a similar fragmentation pattern. All 25-OHD assays should be monitored by a proficiency testing scheme and the results made available to clinicians and editors of scientific journals.

Topics: 25-Hydroxyvitamin D 2; Animals; Calcifediol; Chromatography, High Pressure Liquid; Humans; Internationality; Radioimmunoassay; Reference Standards; Reproducibility of Results; Tandem Mass Spectrometry; Terminology as Topic; United States; United States Government Agencies; Vitamin D; Vitamin D Deficiency

The Institute of Medicine (IOM) report on dietary reference intakes (DRI) for vitamin D is reviewed, along with its implications.. Evidence-based reviews were completed; the IOM committee conducted its own literature search, an open public workshop, and two open sessions, and maintained a public web site for stakeholder input. The consensus report of the 14 scientists on the committee was reviewed by a panel of experts.. Only bone health could be used as an indicator for DRI development. Evidence for extraskeletal outcomes was inadequate, inconsistent, or insufficient to develop DRI. The recommended dietary allowance was found to be 600 IU/d for ages 1-70 yr, corresponding on average to a serum 25-hydroxyvitamin D (25OHD) level of at least 50 nmol/liter (20 ng/ml), and 800 IU/d for those older than 70 yr. Comparison with current levels of 25OHD in the National Health and Nutrition Examination Survey population survey revealed that the vitamin D intake in the United States and Canada is adequate. An upper limit was set at 4000 IU/d for adults, corresponding to an average serum 25OHD level of 125 nmol/liter (50 ng/ml).. Previous reports of an epidemic of vitamin D deficiency in North America were based on an overestimation of adequacy. Population screening with serum 25OHD is therefore not warranted. Current laboratory reference ranges for serum 25OHD are overestimated and should be revised. Practice guidelines to treat disease should not be applied to the healthy American population where use of the DRI is appropriate.

Topics: 25-Hydroxyvitamin D 2; Accidental Falls; Aged; Bone and Bones; Calcium, Dietary; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Diet; Diet Surveys; Dietary Supplements; Health Status; Humans; Metabolic Syndrome; Neoplasms; North America; Nutrition Policy; Public Health; Reference Values; Sunlight; United States; Vitamin D; Vitamin D Deficiency

The aim of the present study is to summarize existing literature on vitamin D levels in adults in different continents and different countries worldwide. The best determinant of vitamin D status is the serum concentration of 25-hydroxyvitamin D (25(OH)D). Most investigators agree that serum 25(OH)D should be higher than 50 nmol/l, but some recommend higher serum levels. Traditional risk groups for vitamin D deficiency include pregnant women, children, older persons, the institutionalized, and non-western immigrants. This chapter shows that serum 25(OH)D levels are not only suboptimal in specific risk groups, but also in adults in many countries. Especially, in the Middle-East and Asia, vitamin D deficiency in adults is highly prevalent.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged, 80 and over; Calcifediol; Child; Female; Global Health; Humans; Male; Pregnancy; Risk Factors; Vitamin D; Vitamin D Deficiency

Vitamin D via its receptor has essential actions on parathyroid cells, inhibiting PTH secretion, and parathyroid cell proliferation. While the effects of vitamin D depletion in the pathogenesis of secondary hyperparathyroidism in elderly individuals or in the occurrence of parathyroid hyperplasia in patients with renal insufficiency are well established, the association between hypovitaminosis D and primary hyperparathyroidism (P-HPT) has only recently become appreciated. In different cohorts of patients with P-HPT, vitamin D deficiency has been recently associated with higher PTH levels, larger adenomas, and a more severe phenotype (including osteitis fibrosa cystica) as well as negative post-operative outcomes following parathyroidectomy. Despite current guidelines recommend measurement of serum 25OHD (25-hydroxy-cholecalciferol) in P-HPT and their repletion if the levels are <20 ng/ml, future well-designed trials of vitamin D supplementation in P-HPT patients with coexisting vitamin D deficiency are needed to evaluate the risk/benefit profile of this treatment.

Topics: 25-Hydroxyvitamin D 2; Adenoma; Bone and Bones; Female; Humans; Hyperparathyroidism, Primary; Parathyroid Hormone; Parathyroidectomy; Postmenopause; Vitamin D; Vitamin D Deficiency

Clinical studies have suggested a possible association of low serum vitamin D levels in patients with bone fractures. This, coupled with a high prevalence of fractures and increases in associated disability and mortality, begs the question, is there evidence to support a role for therapeutic drug monitoring of vitamin D levels to prevent bone fractures? We use a previously published nine-step decision-making algorithm to answer this question. Optimal dosages of vitamin D have not been determined, although daily intake guidelines are suggested. Current vitamin D assays yield varying results, making it challenging for clinicians to interpret results from clinical trials and apply them directly to patients and their specific serum level data. Fracture risk is not easily assessable clinically, with no clear relationship between vitamin D concentrations and bone mineral density. The existing primary literature shows no clear relationship between vitamin D concentrations and fracture risk; target concentrations are not well established. Although the pharmacokinetic parameters of vitamin D are unpredictable and vitamin D supplementation is frequently lifelong, results of a vitamin D assay are unlikely to make a significant difference in the clinical decision-making process (i.e., provide more information than clinical judgment alone). Most published studies on vitamin D levels and fracture risk did not control for other potential reasons to monitor levels, multifactorial risks for fractures, and other confounders. Given limited data to support a direct relation between vitamin D levels and clinical outcome of fracture, inconsistent between-assay results, and no consensus on optimal levels, there is insufficient evidence to recommend routine therapeutic drug monitoring of vitamin D for fracture prevention; however, other reasons for monitoring might exist that are beyond the scope of this review. Recent availability of vitamin D assay standards may lead to future improvements in comparability of research data, establishment of a target range, and interpretability of patient results.

Topics: 25-Hydroxyvitamin D 2; Algorithms; Biomarkers; Blood Chemical Analysis; Bone and Bones; Bone Density; Calcifediol; Calcium; Decision Making; Dietary Supplements; Drug Monitoring; Fractures, Bone; Humans; Osteoporosis; Risk Factors; Vitamin D; Vitamin D Deficiency

The objective of this work is to estimate the economic burden and premature death rate in Canada attributable to low serum 25-hydroxyvitamin D (25(OH)D) levels. Vitamin D deficiency has been linked to many diseases and conditions in addition to bone diseases, including many types of cancer, several bacterial and viral infections, autoimmune diseases, cardiovascular diseases, and adverse pregnancy outcomes. Canadians have mean serum 25(OH)D levels averaging 67 nmol/L. The journal literature was searched for papers reporting dose-response relationships for vitamin D indices and disease outcomes. The types of studies useful in this regard include randomized controlled trials, observational, cross-sectional, and ecological studies, and meta-analyses. The mortality rates for 2005 were obtained from Statistics Canada. The economic burden data were obtained from Health Canada. The estimated benefits in disease reduction were based on increasing the mean serum 25(OH)D level to 105 nmol/L. It is estimated that the death rate could fall by 37,000 deaths (22,300-52,300 deaths), representing 16.1% (9.7-22.7%) of annuals deaths and the economic burden by 6.9% (3.8-10.0%) or $14.4 billion ($8.0 billion-$20.1 billion) less the cost of the program. It is recommended that Canadian health policy leaders consider measures to increase serum 25(OH)D levels for all Canadians.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Canada; Child; Female; Health Care Costs; Humans; Infant; Male; Mortality; Nutrition Policy; Pregnancy; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency is common among patients with myocardial diseases because sun-induced vitamin D production in the skin and dietary intake of vitamin D is often insufficient. Knockout mice for the vitamin D receptor develop myocardial hypertrophy and dysfunction. It has also been shown that children with rickets who suffered from severe heart failure could be successfully treated with supplementation of vitamin D plus calcium. In adults, almost all patients with heart failure exhibit reduced 25-hydroxyvitamin D levels, which are used to classify the vitamin D status. In prospective studies, vitamin D deficiency was an independent risk factor for mortality, deaths due to heart failure and sudden cardiac death. Several vitamin D effects on the electrophysiology, contractility, and structure of the heart suggest that vitamin D deficiency might be a causal factor for myocardial diseases. Data from interventional trials, however, are rare and urgently needed to elucidate whether vitamin D supplementation is useful for the treatment of myocardial diseases. In our opinion, the current knowledge of the beneficial effects of vitamin D on myocardial and overall health strongly argue for vitamin D supplementation in all vitamin D-deficient patients with or at high risk for myocardial diseases.

Topics: 25-Hydroxyvitamin D 2; Adult; Animals; Calcifediol; Cardiomyopathies; Child; Dietary Supplements; Heart; Humans; Infant; Myocardium; Risk Factors; Vitamin D; Vitamin D Deficiency

The use of vitamin D testing has grown rapidly in the recent times as a result of increased interest in the role of vitamin D in health. Although the generally accepted measure of vitamin D status is circulating 25(OH)D concentration, there is little consensus on which assay method should be used. Commonly used assays include competitive protein-binding assay, RIA, enzyme immunoassay, chemiluminescence immunoassays, HPLC, and LC-MS/MS, each with its own advantages and disadvantages. However, there is significant interassay and interlaboratory variability in measurements. Our simulation of the published data showed that using a deficiency cut-point of 50 nmol/L, 57% of samples assessed using a chemiluminescence immunoassay were classified as deficient compared with 41% of samples assessed using LC-MS/MS; a 20% misclassification rate. Similar rates of misclassification were seen at 75 nmol/L. This has implications for clinical practice and decision limits for vitamin D supplementation, suggesting that cut-points should be assay specific rather than universal and that greater harmonization between laboratories is required. Newer assays using alternative biological samples to determine the circulating 25(OH)D have been proposed and advances in the genetics of vitamin D and the role of vitamin D-binding protein may improve future assay accuracy.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Humans; Nutrition Assessment; Nutritional Status; Reproducibility of Results; Vitamin D; Vitamin D Deficiency

Vitamin D insufficiency is a common medical condition. Vitamin supplements can be ingested to improve vitamin D status. It is not known if the vehicle substance that is combined with the vitamin D tablet influences the bioavailability of vitamin D. The purpose of this review is to examine the impact of different vehicles on vitamin D bioavailability. A comprehensive literature search identified studies that directly compared the absorption of vitamin D from two or more vehicles. The change in mean serum 25(OH)D per average daily dose of vitamin D supplemented was calculated and compared among the studies. We identified four clinical studies that compared two different vehicles of vitamin D. Vitamin D in an oil vehicle produced a greater 25(OH)D response than vitamin D in a powder or an ethanol vehicle in healthy subjects. There are limited studies that have compared the influence of the vehicle substance on vitamin D bioavailability. Future studies should examine bioavailability among different vehicle substances such as oil, lactose powder, and ethanol and examine if there are any differences in bioavailability among different patient populations including those with fat malabsorption.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Biological Availability; Calcifediol; Child; Dietary Supplements; Ethanol; Female; Humans; Intestinal Absorption; Male; Pharmaceutical Vehicles; Plant Oils; Powders; Vitamin D; Vitamin D Deficiency

We conducted an examination of recent studies to determine whether older adults (>or=65 years) need higher levels of supplementary vitamin D than young adults when attempting to replete vitamin D status in deficient subjects, i.e. those with levels of 25-hydroxyvitamin D less than 75 nmol/L. As data on repletion with vitamin D(2) have recently been published, we restricted our discussion to the use of vitamin D(3) from dietary supplements, prescriptions for large oral doses, and bolus dosing or injections. Most published dosing regimens failed to achieve 75 nmol/L in most all subjects, whether young adults (<65 years) or older adults (>or=65 years). Whether as daily or bolus oral supplementation, elderly subjects appeared to need more vitamin D3 compared with younger adults, however, baseline levels, endpoints, study duration, compliance, and other factors were different among studies. To ensure most subjects are replete in vitamin D, a daily dose of more than 50 microg (2000 IU) in younger and 125 microg (5000 IU) is required. Other strategies including bolus and loading doses are described. No study reported adverse effects of using oral intakes about the current upper level of 50 microg (2000 IU).

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Aging; Calcifediol; Cholecalciferol; Dietary Supplements; Humans; Middle Aged; Models, Biological; Nutritional Requirements; Nutritional Status; Vitamin D Deficiency; Young Adult

The hypothesis that vitamin D is inversely associated with multiple health outcomes has been studied in the Harvard cohorts, including the Nurses' Health Study I (n=121,700 female nurses aged 37-64 at baseline in 1984), Nurses' Health Study II (n=116,671 female nurses aged 27-44 years at baseline in 1991), Health Professionals Follow-up Study (n=51,529 male health professionals aged 40-75 years at baseline in 1986), and Physicians' Health Study (n=22 071 male physicians aged 40-84 years at baseline in 1982). These studies assessed vitamin D through circulating 25-hydroxyvitamin D, dietary and supplemental intake, predicted 25-hydroxyvitamin D, and vitamin D receptor polymorphisms. This review summarizes studies of vitamin D and various endpoints considered in these cohorts, including risk of cardiovascular disease, hypertension, elevated plasma C-peptide, various cancers, bone fractures, and multiple sclerosis. Based on the multiple observed benefits of vitamin D, this article postulates recommendations for vitamin D intake in the US population for reduced incidence of multiple health outcomes.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cardiovascular Diseases; Cohort Studies; Diet; Dietary Supplements; Female; Fractures, Bone; Health Surveys; Humans; Male; Multiple Sclerosis; Neoplasms; Nutrition Policy; Nutritional Requirements; Polymorphism, Genetic; Receptors, Calcitriol; Vitamin D; Vitamin D Deficiency

This article discusses the amount of vitamin D supplementation needed and the desirable 25-hydroxyvitamin D level to be achieved for optimal fracture prevention.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Animals; Bone Density; Dietary Supplements; Female; Fractures, Bone; Humans; Male; Mice; Middle Aged; Muscle, Skeletal; Randomized Controlled Trials as Topic; Vitamin D; Vitamin D Deficiency; Young Adult

Low vitamin D status, which is endemic due to inadequate oral intake combined with sun avoidance, contributes to musculoskeletal and other pathologies. Although controversial, it is increasingly recommended that serum 25-hydroxyvitamin D (25D) concentrations less than 30 ng/mL be considered suboptimal. Clinicians should appreciate that 25(OH)D measurements, like all quantitative laboratory tests, are subject to assay and biologic variability. Additionally, international standardized calibrators do not exist for 25(OH)D measurement. As such, a single 25(OH)D value of "30 ng/mL" may have substantial variability surrounding it, thereby making 25(OH)D levels of approximately 35 to 40 ng/mL a reasonable therapeutic goal to assure vitamin D adequacy. Achieving such levels often requires vitamin D supplementation. Vitamin D3 (cholecalciferol) or D2 (ergocalciferol) may be used; whether vitamin D3 is more potent than vitamin D2 in maintaining 25(OH)D is controversial.

Topics: 25-Hydroxyvitamin D 2; Ergocalciferols; Humans; Prevalence; Vitamin D; Vitamin D Deficiency

Interest in all aspects of vitamin D seems to be surging due to perhaps the increased number of diverse positive studies suggesting it could prevent a variety of chronic diseases. However, before patients and health care professionals are educated on the preventive aspects of this vitamin that acts more like a hormone, a basic rapid review of vitamin D is needed. There are multiple reasons for the high rate of vitamin D deficiency around the world, including an aging population, obesity, protective skin care measures, skin pigmentation, increased awareness, more utilized diagnostic assays, and perhaps even the lack of natural and fortified food and beverage sources. Various benefits and limitations of vitamin D2 and vitamin D3 supplementation are discussed. The proper use of the vitamin D blood test, also known as "25-OH vitamin D," is important, and changing the normal range of this test may allow for a slightly higher cutoff value based on parathyroid hormone reductions and experience from clinical trials of osteoporosis prevention. The vitamin D doses needed to adequately increase blood levels are provided. Finally, increasing the recommended daily allowance of this vitamin to 800 to 1,000 IU per day may be beneficial for most age groups.

Topics: 25-Hydroxyvitamin D 2; Calcium; Cholecalciferol; Dietary Supplements; Energy Intake; Ergocalciferols; Global Health; Humans; Mass Screening; Nutrition Assessment; Nutrition Policy; Nutritive Value; Reference Values; Reproducibility of Results; Risk Factors; Vitamin D; Vitamin D Deficiency; Vitamins

Hereditary vitamin D receptor defects (HVDRDs) is a more appropriate and precise title for an inborn error of metabolism commonly known as pseudo-vitamin D deficiency or vitamin D dependency, type II. It is a rare autosomal recessive disorder, approximately 70 kindreds were described, but its main importance is elucidating the physiology of vitamin D and calcium homeostasis in humans. Patients usually develop the clinical and biochemical aberrations, identical to vitamin D deficiency, but with high serum levels of calcitriol, within the first year of life (i.e., muscle weakness, bone pain, deformities, and fractures). Defective calcium gut absorption leads to hypocalcemia, secondary hyperparathyroidism, hypophosphatemia, and defective mineralization of newly formed bone matrix. The disease is not cured by vitamin D replacement therapy, although some patients respond to very high doses of vitamin D or its metabolites. Cells derived from patients, mainly cultured skin fibroblasts, were used to assess steps in calcitriol action from cellular uptake to bioresponse and to elucidate the molecular aberrations in the vitamin D receptor (VDR). Point mutations in the VDR gene were identified in every patient examined, and the same defect was observed in the obligatory heterozygotes. The functional characterization of the patient's VDR reflected the localization of the mutation (18 different ones described to date), thus providing vital information about the structure-function relationship in the human VDR and the essentiality of the VDR as the mediator of vitamin D action.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Humans; Receptors, Calcitriol; Vitamin D Deficiency

The aim of this review is to summarize current knowledge on the relation between vitamin D and muscle function. Molecular mechanisms of vitamin D action on muscle tissue have been known for many years and include genomic and non-genomic effects. Genomic effects are initiated by binding of 1,25-dihydroxyvitamin D3 (1,25(OH)2D) to its nuclear receptor, which results in changes in gene transcription of messenger RNA and subsequent protein synthesis. Non-genomic effects of vitamin D are rapid and mediated through a membrane-bound vitamin D receptor (VDR). Genetic variations in the VDR and the importance of VDR polymorphisms in the development of osteoporosis are still a matter of controversy and debate. Most recently, VDR polymorphisms have been described to affect muscle function. The skin has an enormous capacity for vitamin D production and supplies the body with 80-100% of its requirements of vitamin D. Age, latitude, time of day, season of the year and pigmentation can dramatically affect the production of vitamin D in the skin. Hypovitaminosis D is a common feature in elderly people living in northern latitudes and skin coverage has been established as an important factor leading to vitamin D deficiency. A serum 25-hydroxyvitamin D level below 50 nmol/l has been associated with increased body sway and a level below 30 nmol/l with decreased muscle strength. Changes in gait, difficulties in rising from a chair, inability to ascend stairs and diffuse muscle pain are the main clinical symptoms in osteomalacic myopathy. Calcium and vitamin D supplements together might improve neuromuscular function in elderly persons who are deficient in calcium and vitamin D. Thus 800 IU of cholecalciferol in combination with mg of elemental calcium reduces hip fractures and other non-vertebral fractures and should generally be recommended in individuals who are deficient in calcium and vitamin D. Given the strong interdependency of vitamin D deficiency, low serum calcium and high levels of parathyroid hormone, however, it is difficult to identify exact mechanisms of action.

Topics: 25-Hydroxyvitamin D 2; Aged; Blood Pressure; Calcium; Female; Hip Fractures; Humans; Male; Muscle Weakness; Muscle, Skeletal; Muscle, Smooth, Vascular; Parathyroid Hormone; Receptors, Calcitriol; Vitamin D; Vitamin D Deficiency

Four cases of hypovitaminosis D were seen in a general practitioner's population in the Netherlands: a Somalian veiled woman aged 53 and her 11-year-old daughter, a dark-skinned Surinam woman aged 31, and a veiled Moroccan woman aged 56 years. This cause of myopathy has only been recently recognised and is more prevalent than often thought, especially in high-risk groups such as veiled and dark-skinned immigrants who lack sunlight in the Netherlands. Symptoms are muscle pain and mainly proximal muscle weakness resulting in difficulties in ascending a staircase or getting up out of a chair. The diagnosis is made on the basis of a detailed history and measurement of serum 25-hydroxyvitamin D. Calcium and serum alkaline phosphatase activity may be normal. Treatment with ergocalciferol is effective and cheap. As diagnosis and treatment are relatively simple, finding and treating hypovitaminosis D is a rewarding challenge to primary health care practitioners in the Netherlands.

Topics: 25-Hydroxyvitamin D 2; Adult; Child; Cultural Characteristics; Ergocalciferols; Female; Humans; Life Style; Middle Aged; Morocco; Muscle Weakness; Muscular Diseases; Netherlands; Pain; Risk Factors; Skin Pigmentation; Somalia; Suriname; Vitamin D Deficiency

Vitamin D deficiency in immigrants has been known in the UK for 30-40 years. In Denmark, we have become aware of the problem only recently. Of 69 randomly chosen Palestinian women living in Denmark 85% were found to have very low levels of 25-hydroxyvitamin D (< 10 nmol/l). Vitamin D deficiency is caused by inadequate exposure to sunlight and a low dietary content of vitamin D and calcium. Typical symptoms are muscle pain, muscle spasms, diminished muscular strength, deep bone pain, and paraesthesias. The diagnosis can be tested by three blood tests: serum 25-hydroxyvitamin D, serum PTH, and serum alkaline phosphatase. If a combination of low 25-hydroxyvitamin D and secondary hyperparathyroidism is found, the treatment should be high-dose ergocalciferol or cholecalciferol (100,000 IU weekly). If only (isolated) low 25-hydroxyvitamin D is found, treatment with 1000 IU of ergocalciferol or cholecalciferol in combination with one gram of calcium daily will be adequate.

Topics: 25-Hydroxyvitamin D 2; Calcium; Denmark; Emigration and Immigration; Ergocalciferols; Feeding Behavior; Female; Humans; Male; Sunlight; Vitamin D Deficiency

A model of the maternal-fetal metabolism of vitamin D3 is depicted in Fig. 2. 25-OHD3 of maternal origin is metabolized by the maternal kidneys to the potent metabolite, 1,25-(OH)2D3, which acts on the maternal intestine, kidneys, and skeleton. The maternal kidneys and other organs can produce 24,25-(OH)2D3, although this pathway may be suppressed near the end of gestation. The placenta has selective permeability to the vitamin D3 metabolites, with 25-OHD3 crossing from the mother to the fetus more readily than the dihydroxylated metabolites. The onset of the placental synthesis of 1,25-(OH)2D3 during gestation is unknown. Likewise the regulation of the placental 25-OHD3-1 alpha-hydroxylase is unknown. 1,25-(OH)2D3 of placental origin may enter the maternal or the fetal circulation or act locally on the placenta by inducing the synthesis of proteins involved in the cellular transport of Ca. Perhaps one placenta cell type synthesizes 1,25-(OH)2D3 and another cell type possessing a cytoplasmic receptor for 1,25-(OH)2D3 responds to this metabolite. The function of the 24,25-(OH)2D3 produced by the placenta is unknown. The concentration of free 25-OHD3 and free 1,25-(OH)2D3 in the fetal circulation exceeds the maternal levels due to the differences in the DBP concentrations of the two bloodstreams. The 1,25-(OH)2D3 in the fetal bloodstream may originate from either the placenta or the fetal kidneys. The latter site may not be active in utero due to the hypercalcemia and hyperphosphatemia relative to the maternal levels of these ions. 1,25-(OH)2D3 in the fetal bloodstream acts on those fetal tissues containing cytoplasmic receptors for this metabolite. The intestinal mucosa apparently lacks these receptors until sometime during neonatal life. In contrast, fetal bone cells possess receptors for the 1,25-(OH)2D3. The 24,25-(OH)2D3 in the fetal bloodstream may also be involved in the growth and differentiation of the fetal skeleton. However, the precise role of both metabolites in the fetus remains conjectural.

Topics: 25-Hydroxyvitamin D 2; Animals; Calcitonin; Calcium; Dihydroxycholecalciferols; Ergocalciferols; Female; Fetus; Humans; Maternal-Fetal Exchange; Models, Biological; Parathyroid Hormone; Placenta; Pregnancy; Pregnancy Complications; Rats; Vitamin D; Vitamin D Deficiency

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D 2; Animals; Calcitriol; Calcium; Chick Embryo; Dihydroxycholecalciferols; Dogs; Ergocalciferols; Female; Humans; Kidney Diseases; Liver Diseases; Pregnancy; Vitamin D; Vitamin D Deficiency

Although both vitamin D deficiency and obesity are highly prevalent in the UAE, the role of vitamin D metabolites in mediating obesity-related adverse health effects is not clear. We aimed to assess the role of vitamin D metabolites as potential mediators in the association between obesity, inflammation and metabolic risk factors.. 277 participants who were part of a randomized controlled trial had their assessment that included clinical, anthropometric and physical activity data at baseline and at 6 months. Blood and urine samples were taken for measurements of serum 25(OH)D, 25(OH)D metabolites including 25(OH)D3), 25(OH)D2), 1,25(OH)2D3, 3-Epi-D3), metabolic and inflammatory markers and related biochemical variables. Multiple regression analysis used to assess the role of 25(OH)D metabolites in mediating the effect of increasing body mass index (BMI) on inflammation and metabolic risk factors.. Overall, 277 participants with complete 6 months follow up with a mean (±SD) age of 41 ± 12 and 204 (74%) female were included in the study. Blood pressure, inflammatory, metabolic and lipid profile markers significantly increased in overweight and obese subjects compared to subjects with normal BMI both at baseline and at 6 months (p < 0.05). 25(OH)D revealed significant association with age, gender, HbA1c and type 2 diabetes (p < 0.05). No statistically significant changes in any of 25(OH)D metabolites assessed. Multivariate analysis revealed significant and independent associations between BMI and important inflammatory and metabolic risk factors (p < 0.05). No similar association observed with 25(OH)D metabolites.. Although we found significant association between 25(OH)D and prevalence of type 2 diabetes, we found no evidence however to support a role of 25(OH)D metabolites in mediating the effect of BMI on inflammatory or metabolic risk factors.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Mass Index; Calcifediol; Calcitriol; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Multivariate Analysis; Obesity; Risk Factors; Vitamin D; Vitamin D Deficiency

This study investigated whether UVB-exposed wheat germ oil (WGO) is capable to improving the vitamin D status in healthy volunteers.. Participants who received the UVB-exposed WGO were characterized by an increase of circulating 25(OH)D. UVB-exposed WGO containing 23.7 µg vitamin D can increase 25(OH)D. ClinicalTrials.gov: NCT03499327 (registered, April 13, 2018).

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Cholecalciferol; Chromatography, Liquid; Ergocalciferols; Female; Humans; Male; Plant Oils; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency; Vitamins

GC/DBP effects on response to vitamin D supplementation have not been well-studied. Thus we assessed free and total 25-OHD after vitamin D treatment across the six common GC haplotypes.. This double-blind, randomized study compared two vitamin D3 doses in healthy, urban-dwelling 6-month to 10-year-old children at-risk for vitamin D deficiency. Randomization was stratified by GC haplotype.. Children were randomized to receive 2800 or 7000 International Units of vitamin D3 weekly. 25-OHD and 1,25(OH)2D were sampled at baseline and after 1-6 months of supplementation.. One hundred ninety-two of 225 enrolled subjects completed the study. After one month, total 25-OHD increased with both doses and were higher with 7000 IU/week (85.5 ± 22.8 nmol/L) compared to 2800 IU/week (76.8 ± 18.0 nmol/L), despite equivalent baseline levels. No further significant increase occurred at 6 months (89.8 ± 35.5 and 74.3 ± 18.3 nmol/L, respectively). Free 25-OHD similarly changed. 25-OHD differed among GC groups at baseline. Although no significant effects of individual GC haplotypes on incremental changes were evident, a trend toward an effect of combined 'at risk' GC alleles on response was evident (P = 0.06). Total 1,25(OH)2D showed modest increases, moreso with the larger dose. In urban-dwelling children at-risk for vitamin D deficiency, 1 month of vitamin D3 2800 IU/week increased 25-OHD across all GC haplotype groups, and somewhat enhanced with 7000 IU/week with no further significant increases after 6 months of supplementation. Free 25-OHD measures offer no monitoring advantage over total 25-OHD.

Topics: 25-Hydroxyvitamin D 2; Child; Child, Preschool; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Haplotypes; Humans; Infant; Male; Prospective Studies; Vitamin D Deficiency

Prevalence of vitamin D insufficiency/deficiency has been noted in athletic populations, although less is known about recreationally active individuals. Biofortification of natural food sources (e.g. UV radiated mushrooms) may support vitamin D status and is therefore of current scientific and commercial interest. The aim of this study was to assess the impact of a mushroom-derived food ingredient on vitamin D status in recreationally active, healthy volunteers.. Twenty-eight participants were randomly assigned to either: 25 μg (1000 IU) encapsulated natural mushroom-derived vitamin D. Vitamin D status (25(OH)D. The use of a UV radiated mushroom food ingredient was effective in maintaining 25(OH)D

Topics: 25-Hydroxyvitamin D 2; Adult; Agaricales; Calcifediol; Cholecalciferol; Diet; Double-Blind Method; Ergocalciferols; Food, Fortified; Humans; Vitamin D Deficiency

Despite abundant cross-sectional evidence that low vitamin D status is associated with risk of cognitive decline in ageing, interventional evidence for benefits of vitamin D supplementation is lacking. This study was a 6 month randomised, double-blinded placebo-controlled clinical trial of the effects of vitamin D3 (D3), enhanced vitamin D2 in a mushroom matrix (D2M), standard mushroom (SM) and placebo (PL) on cognition and mood in

Topics: 25-Hydroxyvitamin D 2; Affect; Agaricales; Calcifediol; Cholecalciferol; Cognition; Cognitive Dysfunction; Dietary Supplements; Double-Blind Method; Ergocalciferols; Female; Humans; Male; Middle Aged; Seasons; Treatment Outcome; Vitamin D; Vitamin D Deficiency

To study the effects of metformin, as compared to placebo, on serum levels of vitamin D (25-hydroxyvitamin D [25(OH)D]) in patients with advanced type 2 diabetes.. In the HOME trial, a randomized placebo-controlled trial, 390 insulin-treated patients with type 2 diabetes were treated with 850 mg metformin or placebo thrice daily for 52 months. In a post-hoc analysis, we examined changes in the combined levels of 25(OH)D. Mean combined 25(OH)D at baseline was 68.2 nmoL/L (95% confidence interval [CI]: 65.5-71.1). In mixed model analysis, metformin, as compared to placebo, had no effect on 25(OH)D levels during 16 months (coefficient: 1.002 per month, multiplicative model; 95% CI: 0.998-1.006, P = .30). Metformin was associated with a small increase of 25(OH)D. Metformin had no effect on serum 25(OH)D during 16 months in the setting of a clinical randomized controlled trial in patients with type 2 diabetes. Our results show that metformin doesn't lead to vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Age Factors; Aged; Body Mass Index; Calcifediol; Diabetes Mellitus, Type 2; Double-Blind Method; Female; Follow-Up Studies; Humans; Hypoglycemic Agents; Male; Metformin; Middle Aged; Netherlands; Nutritional Status; Outpatient Clinics, Hospital; Overweight; Prevalence; Seasons; Sex Factors; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Biomarkers; Calcifediol; Child; Child Nutritional Physiological Phenomena; Child, Preschool; Cross-Sectional Studies; Female; Follow-Up Studies; Food, Fortified; Humans; Immune System; Infant; Inflammation Mediators; Influenza, Human; Male; Nutrition Assessment; Nutritional Status; Quebec; Respiratory Tract Infections; Seasons; Urban Health; Vitamin D; Vitamin D Deficiency

Previous in vitro and in vivo studies indicate that enzymes that synthesize and metabolize vitamin D are magnesium dependent. Recent observational studies found that magnesium intake significantly interacted with vitamin D in relation to vitamin D status and risk of mortality. According to NHANES, 79% of US adults do not meet their Recommended Dietary Allowance of magnesium.. The aim of this study was to test the hypothesis that magnesium supplementation differentially affects vitamin D metabolism dependent on baseline 25-hydroxyvitamin D [25(OH)D] concentration.. The study included 180 participants aged 40-85 y and is a National Cancer Institute independently funded ancillary study, nested within the Personalized Prevention of Colorectal Cancer Trial (PPCCT), which enrolled 250 participants. The PPCCT is a double-blind 2 × 2 factorial randomized controlled trial conducted in the Vanderbilt University Medical Center. Doses for both magnesium and placebo were customized based on baseline dietary intakes. Subjects were randomly assigned to treatments using a permuted-block randomization algorithm. Changes in plasma 25-hydroxyvitamin D3 [25(OH)D3], 25-hydroxyvitamin D2 [25(OH)D2], 1,25-dihydroxyvitamin D3, 1,25-dihydroxyvitamin D2, and 24,25-dihydroxyvitamin D3 [24,25(OH)2D3] were measured by liquid chromatography-mass spectrometry.. The relations between magnesium treatment and plasma concentrations of 25(OH)D3, 25(OH)D2, and 24,25(OH)2D3 were significantly different dependent on the baseline concentrations of 25(OH)D, and significant interactions persisted after Bonferroni corrections. Magnesium supplementation increased the 25(OH)D3 concentration when baseline 25(OH)D concentrations were close to 30 ng/mL, but decreased it when baseline 25(OH)D was higher (from ∼30 to 50 ng/mL). Magnesium treatment significantly affected 24,25(OH)2D3 concentration when baseline 25(OH)D concentration was 50 ng/mL but not 30 ng/mL. On the other hand, magnesium treatment increased 25(OH)D2 as baseline 25(OH)D increased.. Our findings suggest that optimal magnesium status may be important for optimizing 25(OH)D status. This trial was registered at clinicaltrials.gov as NCT03265483.

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D 2; Aged; Calcifediol; Calcitriol; Dietary Supplements; Ergocalciferols; Female; Humans; Kidney; Magnesium; Magnesium Deficiency; Male; Middle Aged; Nutritional Status; Placebos; Vitamin D; Vitamin D Deficiency

To assess the effect of vitamin D supplementation on neuropathy specific quality of life (NeuroQoL) in patients with painful diabetic neuropathy.. This prospective, open label study was conducted between June 2012 and April 2013. Patients with symptomatic diabetic neuropathy were given a single dose of 600,000 IU intramuscular vitamin D, and NeuroQol was assessed at baseline and at five follow-up visits every 4 weeks.. Of 143 participants, 41.3% were vitamin D deficient (vitamin D < 20 ng/ml). Treatment with vitamin D resulted in a significant increase in 25(OH)D (. Vitamin D is effective in improving quality of life in patients with painful diabetic neuropathy.

Topics: 25-Hydroxyvitamin D 2; Adult; Asymptomatic Diseases; Cost of Illness; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Foot; Diabetic Neuropathies; Female; Follow-Up Studies; Humans; Injections, Intramuscular; Male; Middle Aged; Pain; Pakistan; Peripheral Nervous System Diseases; Psychiatric Status Rating Scales; Quality of Life; Severity of Illness Index; Stress, Psychological; Vitamin D; Vitamin D Deficiency

Human milk is typically low in vitamin D activity (VDA). Whether the vitamin D content of breast milk at birth can be increased by supplementing the mother during pregnancy has not been reported to the best of our knowledge.. We examined the effect of vitamin D supplementation during pregnancy on breast-milk VDA in the first 2 mo of lactation.. Breast-milk samples were obtained from women who were enrolled in a randomized, double-blinded, placebo-controlled trial of vitamin D supplementation during pregnancy. Pregnant women were enrolled at 27 wk of gestation and randomly assigned to the following 3 groups: a placebo group, a group who received one dosage of daily oral vitamin D3 (1000 IU), or a group who received 2 dosages of daily oral vitamin D3 (2000 IU). Serum 25-hydroxyvitamin D [25(OH)D] was measured at enrollment, at 36 wk of gestation, and in cord blood at birth. Study participants who were breastfeeding were invited to provide breast-milk samples for VDA measurement [concentration of vitamin D2, vitamin D3, 25(OH)D2, and 25(OH)D3] at 2 wk and 2 mo postpartum. A linear mixed model was used to compare breast-milk VDA between the 3 study groups.. A total of 75 women provided breast-milk samples (44 women provided breast-milk samples at both 2 wk and 2 mo postpartum). The mean (95% CI) VDA at age 2 wk was 52 IU/L (12, 217 IU/L) in the placebo group, 51 IU/L (17, 151 IU/L) in the 1000-IU group, and 74 IU/L (25, 221 IU/L) in the 2000-IU group; and at age 2 mo, the mean (95% CI) VDA was 45 IU/L (16, 124 IU/L), 43 IU/L (18, 103 IU/L), and 58 IU/L (15, 224 IU/L), respectively. There was no significant interaction in VDA between the sample-collection time and treatment (P = 0.61), but there was a difference between lower- and higher-dosage treatment groups (P = 0.04).. Maternal vitamin D supplementation during pregnancy of 2000 IU/d (compared with 1000 IU/d and with a placebo) results in a higher VDA of breast milk ≥2 mo postpartum. This trial was registered at the Australian New Zealand Clinical Trials Registry as ACTRN12610000483055.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cholecalciferol; Dietary Supplements; Double-Blind Method; Ergocalciferols; Female; Fetal Blood; Humans; Infant, Newborn; Lactation; Male; Maternal Nutritional Physiological Phenomena; Maternal-Fetal Exchange; Milk, Human; New Zealand; Pregnancy; Prenatal Care; Vitamin D; Vitamin D Deficiency; Young Adult

Epidemiological data and the effect of sun exposure on atopic eczema (AE) suggest that vitamin D (vitD) may be involved in the pathogenesis.. To investigate if vitD levels were associated with the presence or severity of AE in the first 2 years of life in children living in south-east Norway.. Infants, recruited to a clinical trial on acute bronchiolitis (n = 404) and from the general population (n = 240), were examined at 1-13 months (first visit) and at 2 years of age (second visit). Caregivers were interviewed using a structured questionnaire. AE was diagnosed clinically, based on well-established criteria. Disease severity was assessed using the SCORing Atopic Dermatitis index. Blood samples were taken for vitD measurements, using liquid chromatography-tandem mass spectrometry and for common filaggrin mutation analyses. Complete data on AE and vitD were available in 596 and 449 children at the first and second visit, respectively.. Atopic eczema was diagnosed in 67 children (11%) at the first visit and in 103 children (23%) at the second. Mean vitD levels were 58·2 nmol L(-1) at the first visit and 66·9 nmol L(-1) at the second. Using vitD level tertiles in multivariate regression analysis, there was no association between vitD levels and AE at either visit, regardless of filaggrin mutation. In children without AE at the first visit, vitD levels did not predict AE at the second.. In this cohort of young children in Norway, we found no association between vitD levels and the presence or severity of AE.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child, Preschool; Cross-Sectional Studies; Dermatitis, Atopic; Filaggrin Proteins; Humans; Infant; Infant, Newborn; Intermediate Filament Proteins; Mutation; Norway; Prospective Studies; Vitamin D Deficiency

Despite numerous animal studies that have illustrated the impact of additional vitamin D in the diet of hens on the resulting egg vitamin D content, the effect of the consumption of such eggs on vitamin D status of healthy individuals has not, to our knowledge, been tested.. We performed a randomized controlled trial (RCT) to investigate the effect of the consumption of vitamin D-enhanced eggs (produced by feeding hens at the maximum concentration of vitamin D3 or serum 25-hydroxyvitamin D [25(OH)D3] lawfully allowed in feed) on winter serum 25(OH)D in healthy adults.. We conducted an 8-wk winter RCT in adults aged 45-70 y (n = 55) who were stratified into 3 groups and were requested to consume ≤2 eggs/wk (control group, in which status was expected to decline), 7 vitamin D3-enhanced eggs/wk, or seven 25(OH)D3-enhanced eggs/wk. Serum 25(OH)D was the primary outcome.. Although there was no significant difference (P > 0.1; ANOVA) in the mean preintervention serum 25(OH)D in the 3 groups, it was ∼7-8 nmol/L lower in the control group than in the 2 groups who consumed vitamin D-enhanced eggs. With the use of an ANCOVA, in which baseline 25(OH)D was accounted for, vitamin D3-egg and 25(OH)D3-egg groups were shown to have had significantly higher (P ≤ 0.005) postintervention serum 25(OH)D than in the control group. With the use of a within-group analysis, it was shown that, although serum 25(OH)D in the control group significantly decreased over winter (mean ± SD: -6.4 ± 6.7 nmol/L; P = 0.001), there was no change in the 2 groups who consumed vitamin D-enhanced eggs (P > 0.1 for both).. Weekly consumption of 7 vitamin D-enhanced eggs has an important impact on winter vitamin D status in adults. This trial was registered at clinicaltrials.gov as NCT02678364.

Topics: 25-Hydroxyvitamin D 2; Aged; Animals; Calcifediol; Chickens; Cholecalciferol; Consumer Behavior; Cooking; Diet; Eggs; Female; Food Preferences; Humans; Ireland; Male; Middle Aged; Nutritive Value; Prevalence; Risk; Seasons; Sensation; Vitamin D Deficiency

Vitamin D is typically supplied in capsule form, both in trials and in clinical practice. However, little is known regarding the efficacy of vitamin D administered via oral sprays - a method that primarily bypasses the gastrointestinal absorption route. This study aimed to compare the efficacy of vitamin D3 liquid capsules and oral spray solution in increasing wintertime total 25-hydroxyvitamin D (25(OH)D) concentrations. In this randomised, open-label, cross-over trial, healthy adults (n 22) received 3000 IU (75 µg) vitamin D3 daily for 4 weeks in either capsule or oral spray form. Following a 10-week washout phase, participants received the opposite treatment for a final 4 weeks. Anthropometrics and fasted blood samples were obtained before and after supplementation, with samples analysed for total 25(OH)D, creatinine, intact parathyroid hormone and adjusted Ca concentrations. At baseline, vitamin D sufficiency (total 25(OH)D>50 nmol/l), insufficiency (31-49 nmol/l) and clinical deficiency (<30 nmol/l) were evident in 59, 23 and 18 % of the participants, respectively. Overall, baseline total mean 25(OH)D concentration averaged 59·76 (sd 29·88) nmol/l, representing clinical sufficiency. ANCOVA revealed no significant difference in the mean and standard deviation change from baseline in total 25(OH)D concentrations between oral spray and capsule supplementation methods (26·15 (sd 17·85) v. 30·38 (sd 17·91) nmol/l, respectively; F=1·044, adjusted r 2 0·493, P=0·313). Oral spray vitamin D3 is an equally effective alternative to capsule supplementation in healthy adults.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Calcifediol; Calcium; Capsules; Cholecalciferol; Cross-Over Studies; Dietary Supplements; Female; Humans; Intention to Treat Analysis; Lost to Follow-Up; Male; Northern Ireland; Oral Sprays; Parathyroid Hormone; Patient Compliance; Seasons; Severity of Illness Index; Vitamin D Deficiency; Young Adult

Patients with chronic kidney disease (CKD) demonstrate complex mineral metabolism derangements and a high prevalence of vitamin D deficiency. However, the optimal method of 25-hydroxyvitamin D (25(OH)D) repletion is unknown, and trials analysing the comparative efficacy of cholecalciferol and ergocalciferol in this population are lacking. We conducted a randomised clinical trial of cholecalciferol 1250μg (50 000 IU) weekly v. ergocalciferol 1250μg (50 000 IU) weekly for 12 weeks in forty-four non-dialysis-dependent patients with stage 3-5 CKD. The primary outcome was change in total 25(OH)D from baseline to week 12 (immediately after therapy). Secondary analyses included the change in 1,25-dihydroxyvitamin D (1,25(OH)2D), parathyroid hormone (PTH), D2 and D3 sub-fractions of 25(OH)D and 1,25(OH)2D and total 25(OH)D from baseline to week 18 (6 weeks after therapy). Cholecalciferol therapy yielded a greater change in total 25(OH)D (45·0 (sd 16·5) ng/ml) v. ergocalciferol (30·7 (sd 15·3) ng/ml) from baseline to week 12 (P<0·01); this observation partially resulted from a substantial reduction in the 25(OH)D3 sub-fraction with ergocalciferol. However, following cessation of therapy, no statistical difference was observed for total 25(OH)D change from baseline to week 18 between cholecalciferol and ergocalciferol groups (22·4 (sd 12·7) v. 17·6 (sd 8·9) ng/ml, respectively; P=0·17). We observed no significant difference between these therapies with regard to changes in serum PTH or 1,25(OH)2D. Therapy with cholecalciferol, compared with ergocalciferol, is more effective at raising serum 25(OH)D in non-dialysis-dependent CKD patients while active therapy is ongoing. However, levels of 25(OH)D declined substantially in both arms following cessation of therapy, suggesting the need for maintenance therapy to sustain levels.

Topics: 25-Hydroxyvitamin D 2; Academic Medical Centers; Adult; Aged; Calcifediol; Calcitriol; Cholecalciferol; Cohort Studies; Dietary Supplements; Double-Blind Method; Ergocalciferols; Female; Follow-Up Studies; Humans; Kansas; Male; Middle Aged; Outpatient Clinics, Hospital; Parathyroid Hormone; Renal Insufficiency, Chronic; Reproducibility of Results; Vitamin D Deficiency

Little is known about how the genetic variation in vitamin D modulating genes influences ultraviolet (UV)B-induced 25-hydroxyvitamin D [25(OH)D] concentrations. In the Food with vitamin D (VitmaD) study, we showed that common genetic variants rs10741657 and rs10766197 in 25-hydroxylase (CYP2R1) and rs842999 and rs4588 in vitamin D binding protein (GC) predict 25(OH)D concentrations at late summer and after 6-mo consumption of cholecalciferol (vitamin D₃)-fortified bread and milk.. In the current study, called the Vitamin D in genes (VitDgen) study, we analyzed associations between the increase in 25(OH)D concentrations after a given dose of artificial UVB irradiation and 25 single nucleotide polymorphisms located in or near genes involved in vitamin D synthesis, transport, activation, or degradation as previously described for the VitmaD study. Second, we aimed to determine whether the genetic variations in CYP2R1 and GC have similar effects on 25(OH)D concentrations after artificial UVB irradiation and supplementation by vitamin D₃-fortified bread and milk.. The VitDgen study includes 92 healthy Danes who received 4 whole-body UVB treatments with a total dose of 6 or 7.5 standard erythema doses during a 10-d period in winter. The VitmaD study included 201 healthy Danish families who were given vitamin D₃-fortified bread and milk or placebo for 6 mo during the winter.. After UVB treatments, rs10741657 in CYP2R1 and rs4588 in GC predicted UVB-induced 25(OH)D concentrations as previously shown in the VitmaD study. Compared with noncarriers, carriers of 4 risk alleles of rs10741657 and rs4588 had lowest concentrations and smallest increases in 25(OH)D concentrations after 4 UVB treatments and largest decreases in 25(OH)D concentrations after 6-mo consumption of vitamin D₃-fortified bread and milk.. Common genetic variants in the CYP2R1 and GC genes modify 25(OH)D concentrations in the same manner after artificial UVB-induced vitamin D and consumption of vitamin D₃-fortified bread and milk.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Animals; Bread; Calcifediol; Child; Cholecalciferol; Cholestanetriol 26-Monooxygenase; Cytochrome P450 Family 2; Denmark; Double-Blind Method; Food, Fortified; Genetic Association Studies; Humans; Male; Middle Aged; Milk; Polymorphism, Single Nucleotide; Seasons; Skin; Ultraviolet Therapy; Vitamin D Deficiency; Vitamin D-Binding Protein; Whole-Body Irradiation; Young Adult

The superiority of cholecalciferol (D3) over ergocalciferol (D2) in sustaining serum 25-hydroxy vitamin D (25OHD) levels is controversial. To compare D2 with D3 we performed a single-blind, placebo-controlled randomized trial spanning 11 weeks.. Healthy volunteers (n=33, aged 33.4±6 years) were divided into three groups (n=11, each): D2, D3 and placebo. Treatment started with a loading dose (100,000 IU) followed by 4800 IU/day (d) between d7 and d20 and follow-up until d77. Serum samples were obtained at baseline and at days 3, 7, 14, 21, 35, 49, 63 and 77.. Baseline 25OHD values in the D2 group were lower than those in the D3 and placebo groups (P<0.01). Placebo 25OHD levels never changed. As after the loading dose both D2 and D3 groups had reached similar 25OHD levels, we tested equivalence of the area under the concentration × time curve (AUC) between d7 and d77. The AUC was 28.6% higher for D3 compared with D2, and both were higher with respect to placebo. At d77, D2 25OHD levels were higher than those at baseline, but similar to placebo; both were lower than D3 (P<0.04). According to raw data, the elimination half-life of 25OHD was 84 and 111 days under D2 and D3 supplementation, respectively; after subtracting the placebo values, the corresponding figures were 33 and 82 days.. D2 and D3 were equally effective in elevating 25OHD levels after a loading dose. In the long term, D3 seems more appropriate for sustaining 25OHD, which could be relevant for classic and non-classic effects of vitamin D.

Topics: 25-Hydroxyvitamin D 2; Adult; Argentina; Calcifediol; Calcium; Cholecalciferol; Dietary Supplements; Ergocalciferols; Female; Follow-Up Studies; Half-Life; Hospitals, University; Hospitals, Urban; Humans; Kinetics; Male; Middle Aged; Models, Biological; Personnel, Hospital; Single-Blind Method; Vitamin D Deficiency; Young Adult

25-Hydroxyvitamin D (25(OH)D) insufficiency is very common in many countries. Yet, the extent to which 25(OH)D status affects cognitive performance remains unclear. The objective of the present study was to evaluate the cross-time association between midlife plasma 25(OH)D concentrations and subsequent cognitive performance, using a subsample from the French 'SUpplémentation en Vitamines et Minéraux AntioXydants' randomised trial (SU.VI.MAX, 1994-2002) and the SU.VI.MAX 2 observational follow-up study (2007-9). 25(OH)D concentrations were measured in plasma samples drawn in 1994-5, using an electrochemoluminescent immunoassay. Cognitive performance was evaluated in 2007-9 with a neuropsychological battery including phonemic and semantic fluency tasks, the RI-48 (rappel indicé-48 items) cued recall test, the Trail Making Test and the forward and backward digit span. Cognitive factors were extracted via principal component analysis (PCA). Data from 1009 individuals, aged 45-60 years at baseline, with available 25(OH)D and cognitive measurements were analysed by multivariable linear regression models and ANCOVA, stratified by educational level. PCA yielded two factors, designated as 'verbal memory' (strongly correlated with the RI-48 and phonemic/semantic fluency tasks) and 'short-term/working memory' (strongly correlated with the digit span tasks). In the fully adjusted regression model, among individuals with low education, there was a positive association between 25(OH)D concentrations and the 'short-term/working memory' factor (P=0.02), mainly driven by the backward digit span (P=0.004). No association with either cognitive factor was found among better educated participants. In conclusion, higher midlife 25(OH)D concentrations were linked to better outcomes concerning short-term and working memory. However, these results were specific to subjects with low education, suggesting a modifying effect of cognitive reserve.

Topics: 25-Hydroxyvitamin D 2; Adult; Aging; Calcifediol; Case-Control Studies; Cognition Disorders; Cohort Studies; Educational Status; Female; France; Humans; Immunoassay; Longitudinal Studies; Male; Memory, Short-Term; Middle Aged; Principal Component Analysis; Risk; Verbal Learning; Vitamin D Deficiency

Epidemiologic data suggest that low serum 25-hydroxyvitamin D [25(OH)D] increases insulin resistance and the risk of type 2 diabetes. Few interventional trials have assessed the effect of vitamin D on insulin metabolism, and published results are discordant.. The goal of this study was to perform a detailed assessment of the effect of ergocalciferol administration on glucose and insulin metabolism in healthy people with low total 25(OH)D(total).. This was a 12-wk, double-blinded, randomized controlled trial. We enrolled 90 healthy volunteers aged 18-45 y with serum 25(OH)D ≤20 ng/mL (by immunoassay) and administered 50,000 IU ergocalciferol/wk or placebo for 12 wk. Primary endpoints were change in first-phase insulin response and insulin sensitivity as measured by intravenous glucose tolerance test. Secondary endpoints included change in homeostasis model assessment of insulin resistance; fasting glucose, insulin, and lipids; body mass index (BMI); and blood pressure.. On-study 25(OH)D(total) was assessed by liquid chromatography-tandem mass spectrometry. In the treated group, 25(OH)D(total) rose from 18 ± 7 to 43 ± 12 ng/mL (P < 0.001) with no change in the placebo group. Despite this increase, at 12 wk, there were no between-group differences in either insulin response or insulin sensitivity; nor were there differences in any measured secondary endpoints. There was no evidence of effect modification by sex, race, glucose tolerance status, baseline 25(OH)D(total), or BMI.. In healthy persons with low 25(OH)D(total), ergocalciferol administration for 12 wk normalizes 25(OH)D(total) but does not improve insulin secretion, insulin sensitivity, or other markers of metabolic health.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Boston; Calcifediol; Cohort Studies; Diabetes Mellitus, Type 2; Dietary Supplements; Double-Blind Method; Ergocalciferols; Female; Humans; Insulin; Insulin Resistance; Insulin Secretion; Longitudinal Studies; Male; Risk; Severity of Illness Index; Vitamin D Deficiency; Young Adult

Experimental evidence has suggested that vitamin D may be protective against tobacco-related cancers through the inhibition of the formation of tumors induced by tobacco carcinogens. To our knowledge, only one previous epidemiologic study investigated the association between vitamin D status and tobacco-related cancer risk, and no study has focused on vitamin D-related gene polymorphisms.. Our objective was to prospectively study the association between plasma 25-hydroxyvitamin D [25(OH)D] concentrations, vitamin D-related gene polymorphisms, and risk of tobacco-related cancers.. A total of 209 tobacco-related cancers were diagnosed within the SU.VI.MAX (Supplémentation en vitamines et minéraux antioxydants) cohort (1994-2007) and were matched with 418 controls as part of a nested case-control study. Tobacco-related cancers (i.e., cancers for which tobacco is one of the risk factors) included several sites in the respiratory, digestive, reproductive, and urinary systems. Total plasma 25(OH)D was assessed with the use of an electrochemoluminescent assay. Polymorphisms were determined with the use of a TaqMan assay. Conditional logistic regression models were computed.. A 25(OH)D concentration ≥30 ng/mL was associated with reduced risk of tobacco-related cancers (OR for ≥30 compared with <30 ng/mL: 0.59; 95% CI 0.35, 0.99; P = 0.046). This association was observed in former and current smokers (OR for ≥30 compared with <30 ng/mL: 0.43; 95% CI: 0.23, 0.84; P = 0.01) but not in never smokers (P = 0.8). The vitamin D receptor (VDR) FokI AA genotype and retinoid X receptor (RXR) rs7861779 TT genotype were associated with increased risk of tobacco-related cancers [OR for homozygous mutant type (MT) compared with wild type (WT): 1.87; 95% CI: 1.08, 3.23; P-trend = 0.02; OR for heterozygous type (HT) plus MT compared with WT: 1.60; 95% CI: 1.07, 2.38; P = 0.02].. In this prospective study, high vitamin D status [25(OH)D concentration ≥30 ng/mL] was associated with decreased risk of tobacco-related cancers, especially in smokers. These results, which are supported by mechanistic plausibility, suggest that vitamin D may contribute to the prevention of tobacco-induced cancers in smokers and deserve additional investigation. The SU.VI.MAX trial was registered at clinicaltrials.gov as NCT00272428.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Calcifediol; Case-Control Studies; Cohort Studies; Double-Blind Method; Female; Follow-Up Studies; France; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Neoplasms; Nutritional Status; Polymorphism, Single Nucleotide; Receptors, Calcitriol; Retinoid X Receptor alpha; Risk Factors; Tobacco Use; Vitamin D Deficiency

Incidence of vitamin D deficiency is increasing worldwide. The purpose of this study was to determine if supplementation with vitamin D2 from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes. Participants were randomised to Portobello mushroom powder (600 IU/d vitamin D2) or placebo for 6 weeks. Participants then completed a 1.5-h exercise session designed to induce skeletal muscle damage. Blood samples and measures of skeletal muscle function were taken pre-supplementation, post-supplementation/pre-exercise and post-exercise. Six weeks supplementation with vitamin D2 increased serum 25(OH)D2 by 9.9-fold and decreased serum 25(OH)D3 by 28%. Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups. In conclusion, 600 IU/d vitamin D2 increased 25(OH)D2 with a concomitant decrease in 25(OD)D3, with no effect on muscular function or exercise-induced muscle damage in high school athletes.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Agaricus; Athletes; Biological Products; Calcifediol; Dietary Supplements; Exercise; Humans; Male; Muscle, Skeletal; Muscular Diseases; Schools; Sports; Vitamin D; Vitamin D Deficiency; Vitamins

Interactions between calcium and vitamin D may have implications for the regulation of serum 25-hydroxyvitamin D [25(OH)D] and its catabolism and, consequently, the vitamin D dietary requirement.. We investigated whether different calcium intakes influenced serum 25(OH)D and indexes of vitamin D activation and catabolism during winter and in the context of both adequate and inadequate vitamin D intakes.. A 15-wk winter-based, randomized, placebo-controlled, double-blind vitamin D₃ intervention (20 μg/d) study was carried out in free-living men and women aged ≥50 y (n = 125) who were stratified according to calcium intakes [moderate-low (<700 mg/d) or high (>1000 mg/d) intake]. The serum 25(OH)D concentration was the primary outcome, and serum calcium, parathyroid hormone (PTH), 1,25-dihydroxyvitamin D [1,25(OH)₂D], 24,25-dihydroxyvitamin D [24,25(OH)₂D], the ratio of 24,25(OH)₂D to 25(OH)D, vitamin D-binding protein, and free 25(OH)D were exploratory outcomes.. A repeated-measures ANOVA showed there was no significant (P = 0.2) time × vitamin D treatment × calcium intake grouping interaction effect on the mean serum 25(OH)D concentration over the 15-wk intervention period. Serum 25(OH)D concentrations increased (P ≤ 0.005) and decreased (P ≤ 0.002) in vitamin D₃ and placebo groups, respectively, and were of similar magnitudes in subjects with calcium intakes <700 mg/d (and even <550 mg/d) compared with >1000 mg/d. The response of serum PTH, 1,25(OH)₂D, 24,25(OH)₂D, the ratio of 24,25(OH)₂D to 25(OH)D, and free 25(OH)D significantly differed in vitamin D₃ and placebo groups but not by calcium intake grouping.. We found no evidence of a vitamin D sparing effect of high calcium intake, which has been referred to by some authors as "vitamin D economy." Thus, recent dietary vitamin D requirement estimates will cover the vitamin D needs of even those individuals who have inadequate calcium intakes.

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Aging; Calcifediol; Calcitriol; Calcium; Calcium, Dietary; Cholecalciferol; Dietary Supplements; Double-Blind Method; Ergocalciferols; Female; Humans; Ireland; Male; Middle Aged; Nutritional Requirements; Seasons; Vitamin D Deficiency

Fundamental knowledge gaps in relation to the 3 epimer of 25-hydroxycholecalciferol [3-epi-25(OH)D₃] limit our understanding of its relevance for vitamin D nutrition and health. The aims of this study were to characterize the 3-epi-25(OH)D₃ concentrations in a nationally representative sample of adults and explore its determinants. We also used data from a recent randomized controlled trial (RCT) of supplemental cholecalciferol (vitamin D₃) conducted in winter in older adults to directly test the impact of changes in vitamin D status on serum 3-epi-25(OH)D3 concentrations. Serum 25-hydroxycholecalciferol [25(OH)D₃] and 3-epi-25(OH)D₃ concentrations (via LC-tandem mass spectrometry) from our vitamin D₃ RCT in adults (aged ≥50 y) and data on dietary, lifestyle, and biochemical characteristics of participants of the recent National Adult Nutrition Survey in Ireland (aged 18-84 y; n = 1122) were used in the present work. In the subsample of participants who had serum 3-epi-25(OH)D₃ concentrations greater than the limit of quantification (n = 1082; 96.4%), the mean, 10th, 50th (median), and 90th percentile concentrations were 2.50, 1.05, 2.18, and 4.30 nmol/L, respectively, whereas the maximum 3-epi-25(OH)D₃ concentration was 15.0 nmol/L. A regression model [explaining 29.9% of the variability in serum 3-epi-25(OH)D₃] showed that age >50 y, vitamin D supplement use, dietary vitamin D, meat intake, season of blood sampling, and sun exposure habits were significant positive determinants, whereas increasing waist circumference and serum 25-hydroxyergocalciferol concentration were significant negative determinants. The RCT data showed that mean serum 25(OH)D₃ and 3-epi-25(OH)D₃ concentrations increased (49.3% and 42.1%, respectively) and decreased (-28.0% and -29.1%, respectively) significantly (P < 0.0001) with vitamin D₃ (20 μg/d) and placebo supplementation, respectively, over 15 wk of winter. In conclusion, we provide data on serum 3-epi-25(OH)D₃ in a nationally representative sample of adults. Our combined observational and RCT data might suggest that both dietary supply and dermal synthesis of vitamin D₃ contribute to serum 3-epi-25(OH)D₃ concentration.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Calcifediol; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Humans; Ireland; Male; Meat; Middle Aged; Nutrition Surveys; Prevalence; Seasons; Severity of Illness Index; Skin; Stereoisomerism; Sunlight; Vitamin D Deficiency

Vitamin D deficiency is a common problem worldwide. Several studies have shown an association between vitamin D deficiency and the increased risk of metabolic syndrome. No previous study has compared the efficacy and safety of ergocalciferol at 40,000 versus 20,000 IU/week in patients with metabolic syndrome.. To evaluate the efficacy of ergocalciferol supplementation on serum 25-hydroxyvitamin D [25(OH)D] concentrations and to examine safety parameters in metabolic syndrome patients.. Outpatient department of Phramongkutklao Hospital, Bangkok, Thailand.. A randomized, double-blinded, parallel study was conducted in metabolic syndrome patients with vitamin D deficiency [25(OH)D <20 ng/mL]. Ninety patients were randomly assigned into three groups of 30 patients each. Group 1 was given two capsules of placebo/week, group 2 was given ergocalciferol 20,000 IU/week, and group 3 was given ergocalciferol 40,000 IU/week for 8 weeks.. serum 25(OH)D concentrations, serum calcium, safety, and corrected QT (QTc) interval.. Of the 90 patients enrolled, 84 patients completed the study. At the end of the study, the mean serum 25(OH)D in groups 2 and 3 significantly increased from the baseline (15.1 and 14.3 to 26.8 and 30.0 ng/mL, respectively). The increase in serum 25(OH)D in groups 2 and 3 were comparable and significantly greater than that of the placebo group. The percentage number of patients achieving normal vitamin D levels in groups 1, 2 and 3 were 3.3, 33.3, and 60.0 %, respectively, which were significantly different between groups (p < 0.001). Adverse reactions in both ergocalciferol treatment groups were not different from the placebo group (p > 0.05). Serum calcium levels did not change within and between groups of treatment. No significant change in QTc was observed in any patient.. Both 20,000 and 40,000 IU/week of ergocalciferol supplementation for 8 weeks were able to increase serum 25(OH)D concentrations significantly. However, more patients in the ergocalciferol 40,000 IU/week treatment group achieved a normal serum 25(OH)D level than in the group which received 20,000 IU/week. Clinicians would have informed of choosing the dosing regimen of ergocalciferol in metabolic syndrome patients.

Topics: 25-Hydroxyvitamin D 2; Aged; Arrhythmias, Cardiac; Calcifediol; Calcium; Dietary Supplements; Double-Blind Method; Ergocalciferols; Female; Humans; Hypercalcemia; Incidence; Male; Metabolic Syndrome; Middle Aged; Thailand; Time Factors; Vitamin D Deficiency

In observational studies, low serum 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with insulin resistance and other risk factors for cardiovascular disease.. We present 1-year data from an ongoing 5-year trial in 511 individuals with impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) randomly assigned to 20,000 IU/week vitamin D3 or placebo. An oral glucose tolerance test was performed at baseline and after 1 year.. Mean baseline serum 25(OH)D was 59.9 nmol/L and 61.1 nmol/L in the vitamin D and placebo groups, respectively, and increased by 45.8 nmol/L and 3.4 nmol/L, respectively. With adjustment for baseline concentrations, no differences in measures of glucose metabolism, insulin secretion or sensitivity, blood pressure, or hs-CRP were found after 1 year. There was a slight, but significant decrease in total and LDL cholesterol in the vitamin D group compared with the placebo group, but as there was also a decrease in HDL cholesterol, the change in the total/HDL cholesterol ratio did not differ significantly. Only analyzing subjects with 25(OH)D <50 nmol/L did not change the results.. This study shows that vitamin D supplementation does not improve glycemic indices, blood pressure, or lipid status in subjects with IFG and/or IGT.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Blood Pressure; Calcifediol; Cholecalciferol; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Dietary Supplements; Double-Blind Method; Female; Glucose Intolerance; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Lipids; Male; Middle Aged; Prediabetic State; Risk Factors; Vitamin D; Vitamin D Deficiency; Vitamins; Young Adult

Vitamin D deficiency affects 1 billion people globally. It has an important role in bone homeostasis, brain development and modulation of the immune system and yet the impact of antenatal vitamin D deficiency on infant outcomes is poorly understood. We assessed the association of 25- hydroxyvitamin D levels (25-OHD) in late pregnancy and early infant growth and developmental outcomes in rural Vietnam.. A prospective cohort study of 960 women who had previously participated in a double-blind cluster randomized controlled trial of antenatal micronutrient supplementation in rural Vietnam was undertaken. Maternal 25-OHD concentration was measured at 32 weeks gestation, and infants were followed until 6 months of age. Main outcome measures were cognitive, motor, socio-emotional and language scores using the Bayley Scales of Infant Development, 3rd edition, and infant length-for-age z scores at 6 months of age.. 60% (582/960) of women had 25-OHD levels <75 nmol/L at 32 weeks gestation. Infants born to women with 25-OHD deficiency (<37.5 nmol/L) had reduced developmental language scores compared to those born to women who were vitamin D replete (≥75 nmol/L) (Mean Difference (MD) -3.48, 95% Confidence Interval (CI) -5.67 to -1.28). For every 25 nmol increase in 25-OHD concentration in late pregnancy, infant length-for-age z scores at 6 months of age decreased by 0.08 (95% CI -0.15 to -0.02).. Low maternal 25- hydroxyvitamin D levels during late pregnancy are of concern in rural Vietnam, and are associated with reduced language developmental outcomes at 6 months of age. Our findings strengthen the evidence for giving vitamin D supplementation during pregnancy.

Topics: 25-Hydroxyvitamin D 2; Adult; Child Development; Dietary Supplements; Female; Humans; Infant, Newborn; Male; Pregnancy; Rural Population; Vietnam; Vitamin D; Vitamin D Deficiency

The vitamin D-endocrine system is thought to play a role in physiologic processes that range from mineral metabolism to immune function. Serum 25-hydroxyvitamin D [25(OH)D] is the accepted biomarker for vitamin D status. Skin color is a key determinant of circulating 25(OH)D concentrations, and genes responsible for melanin content have been shown to be under strong evolutionary selection in populations living in temperate zones. Little is known about the effect of latitude on mean concentrations of 25(OH)D in dark-skinned populations.. The objective was to describe the distribution of 25(OH)D and its subcomponents in 5 population samples of African origin from the United States, Jamaica, Ghana, South Africa, and the Seychelles.. Participants were drawn from the Modeling of the Epidemiologic Transition Study, a cross-sectional observational study in 2500 adults, ages 25-45 y, enrolled between January 2010 and December 2011. Five hundred participants, ∼50% of whom were female, were enrolled in each of 5 study sites: Chicago, IL (latitude: 41°N); Kingston, Jamaica (17°N); Kumasi, Ghana (6°N); Victoria, Seychelles (4°S); and Cape Town, South Africa (34°S). All participants had an ancestry primarily of African origin; participants from the Seychelles trace their history to East Africa.. A negative correlation between 25(OH)D and distance from the equator was observed across population samples. The frequency distribution of 25(OH)D in Ghana was almost perfectly normal (Gaussian), with progressively lower means and increasing skewness observed at higher latitudes.. It is widely assumed that lighter skin color in populations outside the tropics resulted from positive selection, driven in part by the relation between sun exposure, skin melanin content, and 25(OH)D production. Our findings show that robust compensatory mechanisms exist that create tolerance for wide variation in circulating concentrations of 25(OH)D across populations, suggesting a more complex evolutionary relation between skin color and the vitamin D pathway.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Black People; Calcifediol; Chicago; Cross-Sectional Studies; Female; Ghana; Humans; Jamaica; Male; Middle Aged; Models, Biological; Risk; Seychelles; Skin; Skin Pigmentation; South Africa; Sunlight; Ultraviolet Rays; Vitamin D Deficiency

Low serum 25-hydroxyvitamin D is a risk factor for osteoporosis, cardiovascular disease, diabetes, and cancer. Disruption of noncholesterol sterol absorption due to cholesterol-lowering therapies may result in reduced fat-soluble vitamin absorption.. We have previously reported on the cholesterol-lowering efficacy and reduced sterol absorption of probiotic bile salt hydrolase active Lactobacillus reuteri NCIMB 30242; however, the effects on fat-soluble vitamins was previously unknown and the objective of the present study. DESIGN, SETTINGS, PATIENTS, AND INTERVENTION: The study was double-blind, placebo-controlled, randomized, parallel-arm, multicenter lasting 13 weeks. A total of 127 otherwise healthy hypercholesterolemic adults with low-density lipoprotein-cholesterol >3.4 mmol/L, triglycerides <4.0 mmol/L, and body mass index of 22 to 32 kg/m² were included. Subjects were recruited from 6 private practices in Prague, Czech Republic, and randomized to consume L. reuteri NCIMB 30242 or placebo capsules over a 9-week intervention period.. The primary outcome measure was the change in serum low-density lipoprotein-cholesterol over the 9-week intervention. Analysis of fat-soluble vitamins at weeks 0 and 9 were performed post hoc.. There were no significant differences between L. reuteri NCIMB 30242 and placebo capsule groups in serum vitamin A, vitamin E, or β-carotene or dietary intake over the intervention period (P > .05). L. reuteri NCIMB 30242 increased serum 25-hydroxyvitamin D by 14.9 nmol/L, or 25.5%, over the intervention period, which was a significant mean change relative to placebo of 17.1 nmol/L, or 22.4%, respectively (P = .003).. To our knowledge, this is the first report of increased circulating 25-hydroxyvitamin D in response to oral probiotic supplementation.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Amidohydrolases; Anticholesteremic Agents; Bacterial Proteins; Calcifediol; Cholesterol, LDL; Czech Republic; Double-Blind Method; Female; Humans; Hypercholesterolemia; Intestinal Absorption; Limosilactobacillus reuteri; Male; Middle Aged; Probiotics; Vitamin D; Vitamin D Deficiency; Young Adult

We previously showed that a single high dose of oral (po) cholecalciferol (D₃) sharply increases serum 25-hydroxyvitamin D [25(OH)D].. We evaluated the long-term bioavailability and metabolism of a single po or intramuscular (im) high dose of ergocalciferol (D₂) or D₃.. This was a prospective intervention study.. The study was conducted in an ambulatory care setting.. Participants were 24 subjects with hypovitaminosis D.. A single dose of 600,000 IU of po or im D₂ or D₃ was administered.. Serum 25(OH)D and 1,25-dihydroxyvitamin D [1,25(OH)₂D] were measured at baseline and at days 30, 60, 90, and 120 by RIA. Serum 1,25(OH)₂D₂, 1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃], 24,25-hydroxyvitamin D₂ [24,25(OH)D₂], and 24,25-hydroxyvitamin D₃ [24,25(OH)D₃] were measured by liquid chromatography-tandem mass spectrometry in a subgroup of patients receiving the po formulations.. The areas under the curve of 25(OH)D after D₃ were significantly higher than those after D₂ (P < .0001). Serum 25(OH)D basal difference significantly increased at day 30 with po D₂ and D₃ (P < .01 and P < .0001) and up to day 90 with po D₃ (P < .01). The im formulations produced a slow increased, and values peaked at day 120 relative to the other time points (P < .0001). We found a decrease in 1,25(OH)₂D at day 30 (P < .05) and up to day 120 (P < .001) and an increase in 1,25(OH)₂D₂ at day 30 (P < .01) and up to day 120 (P < .01) after po D₂. Oral D₂ and D₃ produced increases in 24,25(OH)D₂ and 24,25(OH)D₃, respectively, at day 30 (P < .001).. A po dose of 600,000 IU of D₂ or D₃ is initially more effective in increasing serum 25(OH)D than the equivalent im dose and is rapidly metabolized. Our RIA assay for 1,25(OH)₂D may not recognize 1,25(OH)₂D₂.

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D 2; Administration, Oral; Aged; Biological Availability; Biotransformation; Calcifediol; Cholecalciferol; Chromatography, High Pressure Liquid; Ergocalciferols; Female; Humans; Injections, Intramuscular; Male; Middle Aged; Radioimmunoassay; Reproducibility of Results; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Vitamin D Deficiency

The biological equivalency of ergocalciferol (D2) and cholecalciferol (D3) has been debated; several comparisons have appeared in the adult literature but are scarce in pediatrics. The objective of this study was to compare increases in plasma 25-hydroxyvitamin D [25(OH)D] concentrations and attainment of 50 and 75 mol/L status cutoffs following 3 mo of daily supplementation with D2 compared with D3. Healthy, breast-fed, 1-mo-old infants (n = 52) received 10 μg (400 ic) of either D2 or D3 daily. At 1 and 4 mo of age, plasma 25-hydroxyergocalciferol and 25-hydroxycholecalciferol concentrations were determined by liquid chromatography tandem MS (LC-MS/MS) and total 25(OH)D by chemiluminescent immunoassay (DiaSorin Liaison). Data were analyzed using t tests and χ² by intent to treat. A total of 23% of infants were deficient (≤24.9 nmol/L) at baseline and 2% at follow-up on the basis of LC-MS/MS. At 4 mo, 96% were breastfed and there were no differences in compliance, breastfeeding rates, or sun exposure among groups. The change in total 25(OH)D measured by LC-MS/MS did not differ between the D2 (17.6 ± 26.7 nmol/L) and D3 (22.2 ± 20.2 nmol/L) groups. In the combined groups, the baseline plasma 25(OH)D concentration was inversely related to the change in total 25(OH)D (r = -0.52; P < 0.001). Overall, 86% of infants met the 50 nmol/L cutoff at follow-up; however, fewer infants in the D2 group (75%) met this level compared with the D3 group (96%) (P < 0.05). Similar results were obtained by immunoassay. In conclusion, the increase in the 25(OH)D concentration among the D2 and D3 groups did not differ, suggesting daily intake of either isoform is acceptable for infants <4 mo.

Topics: 25-Hydroxyvitamin D 2; Adult; Breast Feeding; Calcifediol; Cholecalciferol; Chromatography, High Pressure Liquid; Dietary Supplements; Ergocalciferols; Female; Follow-Up Studies; Humans; Immunoassay; Infant; Intention to Treat Analysis; Male; Patient Compliance; Quebec; Remission Induction; Tandem Mass Spectrometry; Vitamin D Deficiency

Low levels of 25-hydroxyvitamin D (25(OH)VitD) have been recognized as an emerging cardiovascular disease (CVD) risk factor. Statins are reported to increase 25(OH)VitD concentration. Animal studies suggest that ezetimibe is a moderate inhibitor of intestinal 25(OH)VitD absorption, but its effect in humans is unknown.. To investigate whether combined treatment with simvastatin/ezetimibe 10/10 mg would increase 25(OH)VitD levels compared to simvastatin 40 mg monotherapy in patients with primary hypercholesterolemia.. In a Prospective Randomized Open-label Blinded End point study, 50 patients with primary hypercholesterolemia received either simvastatin/ezetimibe 10/10 mg (n = 25) or simvastatin 40 mg (n = 25) daily for 3 months. The primary end point was between-group difference in the change of serum 25(OH)VitD levels.. Simvastatin/ezetimibe 10/10 mg was associated with a 36.7% increase in 25(OH)VitD serum levels (from 6.8 to 9.3 ng/mL, P = .000), while simvastatin 40 mg was associated with a 79.1% increase (from 6.7 to 12.0 ng/mL, P = .008). The increase in 25(OH)VitD levels in the simvastatin 40 mg group was significantly greater compared to that in the simvastatin/ezetimibe 10/10 mg group (P = .04). Both groups exhibited similar reductions in low-density lipoprotein cholesterol (LDL-C) levels.. For similar LDL-C lowering simvastatin 40 mg is associated with greater increase in 25(OH)VitD compared to simvastatin/ezetimibe 10/10 mg. Whether this difference is relevant in terms of CVD risk reduction is unknown.

Topics: 25-Hydroxyvitamin D 2; Aged; Anticholesteremic Agents; Azetidines; Calcifediol; Cardiovascular Diseases; Drug Combinations; Ezetimibe, Simvastatin Drug Combination; Female; Gastrointestinal Agents; Greece; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hypercholesterolemia; Male; Membrane Proteins; Membrane Transport Modulators; Membrane Transport Proteins; Middle Aged; Risk; Simvastatin; Up-Regulation; Vitamin D Deficiency

We wanted to evaluate the cutaneous synthesis of 25OHD and cholecalciferol after one whole-body exposure to ultraviolet radiation type B (UVB) in a randomized setup. Healthy volunteers were randomized to one whole-body exposure in a commercial tanning bed with UVB emission (UVB/UVA ratio 1.8-2.0%) or an identical placebo tanning bed without UVB. The output in the 280-320 nm range was 450 µW/cm². Blood samples were analyzed for 25OHD and cholecalciferol at baseline and during 7 days after treatment. We included 20 volunteers, 11 to UVB and 9 to placebo treatment. During the first 6 h, no significant differences in 25OHD between the groups were found. At the end of the study, we found a mean increase of 25OHD in the UVB group of 4.5 nmol/l (SD 7 nmol/l) compared to a decline of -1.2 nmol/l (SD 7 nmol/l) in the placebo group (p = 0.1). A linear mixed model yielded an increase of 25OHD in the UVB group of 1.0 nmol/l per 24 h (p < 0.01). For cholecalciferol, we found a near significant increase of 1 pmol/l per hour in the UVB group compared to the placebo group during the first 6 h (p = 0.052). One tanning bed session had significant, but modest impact on the level of 25OHD during 7 days after exposure to UVB.

Topics: 25-Hydroxyvitamin D 2; Adult; Beauty Culture; Calcifediol; Cholecalciferol; Denmark; Double-Blind Method; Guidelines as Topic; Humans; Kinetics; Middle Aged; Skin; Ultraviolet Rays; Vitamin D Deficiency; White People; Whole-Body Irradiation

Uncertainty remains regarding the efficacy of low intakes of ergocalciferol (vitamin D2 or D2) and cholecalciferol (vitamin D3 or D3) provided in food to increase serum 25-hydroxy-vitamin D (25-OH-D) metabolite concentrations when UV-B exposure is low. We recruited 40 healthy men and women into a double-blind, parallel design, randomized controlled trial. Participants received placebo or 1 of 4 experimental treatments (D2 or D3 at 5 or 10 μg/d) supplied as a malted milk drink for 4 wk during a period of minimal UV-B exposure in the UK. The primary outcome was a change in serum 25-OH-D2 and 25-OH-D3 concentrations measured by ultra-performance liquid chromatography tandem MS. The secondary outcomes were changes in concentrations of plasma parathyroid hormone and serum calcium (Ca(2+)). Baseline concentrations (geometric mean ± SD) of 25-OH-D2, 25-OH-D3, and total 25-OH-D were 3 ± 4, 32 ± 22, and 37 ± 22 nmol/L, respectively. Both D2- and D3-fortified drinks resulted in dose-dependent increases (P < 0.001) in their respective 25-OH metabolites that did not significantly differ in size. Increments from baseline compared with the placebo group following 5 and 10 μg/d of D2 were (mean ± SEM) 9.4 ± 2.5 and 17.8 ± 2.4 nmol/L for 25-OH-D2 and following 5 and 10 μg/d of D3 were 15.1 ± 4.7 and 22.9 ± 4.6 nmol/L for 25-OH-D3, respectively. There was no difference between D2 and D3 groups in the incremental AUC of their respective metabolites. These findings suggest that D2 and D3 are equipotent in increasing 25-OH-D in healthy men and women with negligible UV-B exposure.

Topics: 25-Hydroxyvitamin D 2; Adult; Animals; Area Under Curve; Calcifediol; Calcium; Cholecalciferol; Chromatography, High Pressure Liquid; Diet; Dose-Response Relationship, Drug; Double-Blind Method; Ergocalciferols; Female; Food, Fortified; Humans; Male; Mass Spectrometry; Milk; Parathyroid Hormone; Ultraviolet Rays; United Kingdom; Vitamin D; Vitamin D Deficiency; Vitamins; Young Adult

To assess effects of vitamin D and Calcium (Ca) on hormonal and metabolic milieu of polycystic ovary syndrome (PCOS).. Single arm open label trial.. Twelve overweight and vitamin D deficient women with PCOS underwent a 2 hour oral glucose tolerance testing at baseline and following 3-month supplementation with vitamin D (daily dose of 3533 IU, increased to 8533 IU after the first five participants) and 530 mg elemental Ca daily.. Blood pressure (BP), plasma glucose, insulin, total testosterone (T) androstenedione (A), sex hormone binding globulin, lifestyle parameters were assessed at baseline and following 3-month intervention. Insulin resistance (IR) and area under the curve for glucose and insulin were computed; paired analyses were conducted.. Improved serum 25OHD (p < 0.001) and reductions in total T (p = 0.036) and A (p = 0.090) levels were noted following 3-month supplementation, compared to baseline. Significant lowering in BP parameters was seen in participants with baseline BP ≥ 120/80 mmHg (n = 8) and in those with baseline serum 25OHD ≤20 ng/ml (n = 9). Parameters of glucose homeostasis and IR remained unchanged (p > 0.05).. Androgen and BP profiles improved followed three month intervention, suggesting therapeutic implications of vitamin D and Ca in overweight and vitamin D deficient women with PCOS.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Mass Index; Calcifediol; Calcium, Dietary; Cholecalciferol; Cohort Studies; Dietary Supplements; Ergocalciferols; Female; Humans; Hyperandrogenism; Hypertension; Overweight; Patient Dropouts; Pilot Projects; Polycystic Ovary Syndrome; Testosterone Congeners; Vitamin D Deficiency; Young Adult

Vitamin D deficiency is associated with a variety of chronic metabolic diseases. Limited evidence regarding vitamin D deficiency exists within the Chinese population. The present study aims to examine the association between serum vitamin D concentrations and cardiometabolic risk factors in the young and middle-aged, urban Chinese population. The cross-sectional relationships between serum 25-hydroxyvitamin D [25(OH)D] concentrations and indices of adiposity and cardiometabolic risk factors (e.g., body mass index, waist circumference, fasting plasma glucose, etc.) were evaluated in 601 non-diabetic adults.. Vitamin D deficiency or insufficiency was present in 66% of the tested population, and serum 25(OH)D levels were lower in patients who were overweight/obese or suffered metabolic syndrome when compared to individuals of healthy weight without metabolic syndrome (24.08 ± 8.08 vs 31.70 ± 11.77 ng/ml, 21.52 ± 6.9 vs 31.74 ± 10.21 ng/ml respectively). 25(OH)D was inversely associated with waist circumference, fasting glucose, fasting insulin, triglycerides and LDL-cholesterol, and it was positively associated with HDL-cholesterol in a multivariable-adjusted regression model.. Vitamin D deficiency is common in the young and middle-aged, urban Chinese population, with high prevalence in overweight/obese individuals and patients with metabolic syndrome. Low vitamin D concentration was associated with indices of adiposity and cardiometabolic risk factors. Further studies are warranted to elucidate the cause-effect relation between vitamin D status, obesity and related metabolic disorders.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Body Mass Index; Calcifediol; China; Cohort Studies; Cross-Sectional Studies; Female; Hospitals, Urban; Humans; Incidence; Male; Metabolic Syndrome; Middle Aged; Obesity; Overweight; Prevalence; Risk Factors; Severity of Illness Index; Urban Health; Vitamin D Deficiency

Vitamin D concentrations are linked to body composition indices, particularly body fat mass. Relationships between hypovitaminosis D and obesity, described by both BMI and waist circumference, have been mentioned. We have investigated the effect of a 12-week vitamin D3 supplementation on anthropometric indices in healthy overweight and obese women.. In a double-blind, randomized, placebo-controlled, parallel-group trial, seventy-seven participants (age 38 ± 8.1 years, BMI 29.8 ± 4.1 kg/m²) were randomly allocated into two groups: vitamin D (25 μg per day as cholecalciferol) and placebo (25 μg per day as lactose) for 12 weeks. Body weight, height, waist, hip, fat mass, 25(OH) D, iPTH, and dietary intakes were measured before and after the intervention.. Serum 25(OH)D significantly increased in the vitamin D group compared to the placebo group (38.2 ± 32.7 nmol/L vs. 4.6 ± 14.8 nmol/L; P<0.001) and serum iPTH concentrations were decreased by vitamin D3 supplementation (-0.26 ± 0.57 pmol/L vs. 0.27 ± 0.56 pmol/L; P<0.001). Supplementation with vitamin D3 caused a statistically significant decrease in body fat mass in the vitamin D group compared to the placebo group (-2.7 ± 2.1 kg vs. -0.47 ± 2.1 kg; P<0.001). However, body weight and waist circumference did not change significantly in both groups. A significant reverse correlation between changes in serum 25(OH) D concentrations and body fat mass was observed (r = -0.319, P = 0.005).. Among healthy overweight and obese women, increasing 25(OH) D concentrations by vitamin D3 supplementation led to body fat mass reduction.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Body Mass Index; Calcifediol; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Humans; Iran; Middle Aged; Obesity; Overweight; Parathyroid Hormone; Patient Compliance; Patient Dropouts; Time Factors; Vitamin D Deficiency

For young children, the level of vitamin D required to ensure that most achieve targeted serum 25-hydroxyvitamin D [25(OH)D] ≥50 nmol/L has not been studied. We aimed to investigate the effect of vitamin D-fortified milk on serum 25(OH)D and parathyroid hormone (PTH) concentrations and to examine the dose-response relationship between vitamin D intake from study milks and serum 25(OH)D concentrations in healthy toddlers aged 12-20 mo living in Dunedin, New Zealand (latitude 46°S). Data from a 20-wk, partially blinded, randomized trial that investigated the effect of providing red meat or fortified toddler milk on the iron, zinc, iodine, and vitamin D status in young New Zealand children (n = 181; mean age 17 mo) were used. Adherence to the intervention was assessed by 7-d weighed diaries at wk 2, 7, 11, 15, and 19. Serum 25(OH)D concentration was measured at baseline and wk 20. Mean vitamin D intake provided by fortified milk was 3.7 μg/d (range, 0-10.4 μg/d). After 20 wk, serum 25(OH)D concentrations but not PTH were significantly different in the milk groups. The prevalence of having a serum 25(OH)D <50 nmol/L remained relatively unchanged at 43% in the meat group, whereas it significantly decreased to between 11 and 15% in those consuming fortified study milk. In New Zealand, vitamin D intake in young children is minimal. Our findings indicate that habitual consumption of vitamin D-fortified milk providing a mean intake of nearly 4 μg/d was effective in achieving adequate year-round serum 25(OH)D for most children.

Topics: 25-Hydroxyvitamin D 2; Animals; Calcifediol; Diet Records; Double-Blind Method; Female; Food, Fortified; Humans; Infant; Infant Food; Male; Milk; New Zealand; Parathyroid Hormone; Patient Compliance; Prevalence; Seasons; Time Factors; Vitamin D; Vitamin D Deficiency

Low vitamin D status in women of childbearing age may have implications for health. Vitamin D status of New Zealanders (NZ), based on low serum 25-hydroxyvitamin D (25OHD) is suboptimal. Vitamin D status may be improved with supplements and/or fortified foods. Recently an Adequate Intake (AI) for Australia and NZ was set at 5 microg/d vitamin D. We aimed to determine the effect of daily consumption of milk powder fortified with 5 microg vitamin D3 on serum 25OHD concentration over 12 wks. 73 non-pregnant women (18 - 47 y) living in Dunedin, NZ (46 degrees S) were randomised to receive either unfortified (control) or fortified (5 microg vitamin D3) milk for 12 wks from January to April. Mean 25OHD was similar between groups at week 0 (control 74 vs 76 nmol/L) and fell significantly in both groups over the 12 weeks (control 53 nmol/L, fortified 65 nmol/L; p < 0.001). After 12 wks the fortified milk group had a serum 25OHD 19% (95% CI; 7, 32%) higher (10 nmol/L) than the control group after adjusting for baseline levels (p < 0.001). Daily consumption of fortified milk providing the current AI of 5 microg day vitamin D3 for 12 weeks resulted in higher 25OHD concentrations than control milk. This dose was not sufficient to prevent the seasonal decline in 25OHD. This study suggests an AI of 5 microg may be inadequate for New Zealanders to allow for seasonal changes in sunlight exposure, and is unlikely sufficient for other populations with low sunlight exposure.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Animals; Calcifediol; Cholecalciferol; Double-Blind Method; Female; Food, Fortified; Humans; Middle Aged; Milk; New Zealand; Nutrition Policy; Nutritional Requirements; Nutritional Status; Nutritive Value; Seasons; Surveys and Questionnaires; Vitamin D Deficiency; Young Adult

To test whether a single large dose of vitamin D2 can improve endothelial function in patients with Type 2 diabetes mellitus and low serum 25-hydroxyvitamin D levels.. Double-blind, parallel group, placebo-controlled randomized trial. A single dose of 100,000 IU vitamin D2 or placebo was administered to patients with Type 2 diabetes over the winter, when levels of circulating 25-hydroxyvitamin D were likely to be lowest. Patients were enrolled if their baseline 25-hydroxyvitamin D level was < 50 nmol/l. Endothelial function and blood pressure were measured and fasting blood samples were taken at baseline and 8 weeks after administration of vitamin D.. Forty-nine per cent of subjects screened had 25-hydroxyvitamin D levels < 50 nmol/l. Thirty-four subjects completed the study, with a mean age of 64 years and a baseline 25-hydroxyvitamin D level of 38.3 nmol/l. Vitamin D supplementation increased 25-hydroxyvitamin D levels by 15.3 nmol/l relative to placebo and significantly improved flow mediated vasodilatation (FMD) of the brachial artery by 2.3%. The improvement in FMD remained significant after adjusting for changes in blood pressure. Vitamin D supplementation significantly decreased systolic blood pressure by 14 mmHg compared with placebo; this did not correlate with change in FMD.. Vitamin D insufficiency is common in patients with Type 2 diabetes during winter in Scotland. A single large dose of oral vitamin D2 improves endothelial function in patients with Type 2 diabetes and vitamin D insufficiency.

Topics: 25-Hydroxyvitamin D 2; Aged; Blood Pressure; Diabetes Mellitus, Type 2; Dietary Supplements; Endothelium; Female; Humans; Male; Middle Aged; Statistics as Topic; Vitamin D; Vitamin D Deficiency

Serum 25-hydroxyvitamin D (25OHD) concentrations greater than 30 ng/ml have been recommended for lowering fracture risk.. Our objective was to determine whether 25OHD sufficiency is a prerequisite for effective response to teriparatide (TPTD).. Data were from 1620 osteoporotic postmenopausal women in the Fracture Prevention Trial. The response to TPTD was assessed in women subgrouped by having 25OHD insufficiency (>10 but 30 but 0.10). However, it should be noted that because of the limited number of fractures, this study does not exclude the possibility of differences in fracture outcome between the subgroups.. In postmenopausal women with osteoporosis and normal intact PTH, the responses to TPTD did not differ significantly in women with baseline 25OHD insufficiency or sufficiency.

Topics: 25-Hydroxyvitamin D 2; Aged; Biomarkers; Bone Density; Bone Density Conservation Agents; Bone Development; Calcifediol; Calcium; Collagen Type I; Double-Blind Method; Female; Fractures, Bone; Humans; Middle Aged; Nutritional Status; Osteoporosis, Postmenopausal; Radiography; Risk Reduction Behavior; Spinal Fractures; Teriparatide; Vitamin D Deficiency

In a random and prospective study, Alzheimer's disease (AD) patients were assigned to regular sunlight exposure (n = 132) or sunlight deprivation (n = 132) and followed for 1 year. Serum 25-OHD level increased by 2.2-fold in the sunlight-exposed group. Eleven patients sustained fractures in the sunlight-deprived group, and three fractures occurred among the sunlight-exposed group (p = 0.0362; odds ratio = 3.7).. A high incidence of fractures, particularly of the hip, represents an important problem in patients with Alzheimer's disease (AD), who are prone to falls and have osteoporosis. We previously showed that 25-hydroxyvitamin D (25-OHD) deficiency caused by sunlight deprivation with compensatory hyperparathyroidism causes reduced BMD in elderly women with AD. This study was undertaken to address the possibility that sunlight exposure with calcium supplementation may maintain BMD and reduce the incidence of nonvertebral fractures in elderly women with AD.. In a random and prospective study, AD patients were assigned to regular sunlight exposure (n = 132) or sunlight deprivation (n = 132) and followed for 1 year. BMD of the second metacarpal bone was measured using a computed X-ray densitometer (CXD). The CXD method measures BMD and cortical thickness at the middle of the second metacarpal bone on a radiogram of the hand and an aluminum step wedge as a standard (20 steps; 1 mm/step). Incidence of nonvertebral fractures in the two patient groups during the 1-year follow-up period was assessed.. At baseline, average hospitalization period was 1.7 years in both groups, and activity of daily living (ADL) was decreased. Patients of both groups showed vitamin D deficiency caused by sunlight deprivation and decreased dietary intake of vitamin D with compensatory hyperparathyroidism. The exposed group patients were exposed to sunlight (3615 minutes/year). BMD increased by 2.7% in the sunlight-exposed group and decreased by 5.6% in the sunlight-deprived group (p < 0.0001). Serum 25-OHD level increased from 24.0 to 52.2 nM in the sunlight-exposed group. Eleven patients sustained fractures in the sunlight-deprived group, and three fractures occurred among the sunlight-exposed group (p = 0.0362; odds ratio = 3.7). Sunlight exposure can increase the BMD of vitamin D-deficient bone by increasing 25-OHD concentration and lead to the prevention of nonvertebral fractures.

Topics: 25-Hydroxyvitamin D 2; Absorptiometry, Photon; Aged; Alzheimer Disease; Biomarkers; Bone and Bones; Bone Density; Female; Fractures, Bone; Heliotherapy; Humans; Muscles; Osteoporosis; Treatment Outcome; Vitamin D Deficiency

Does a sojourn at high altitude during the winter and spring improve vitamin D status (and possibly suppress parathyroid hormone [PTH]) in patients with ankylosing spondylitis (AS)? In 73 patients with AS, serum concentrations of 25-hydroxy-vitamin D [25(OH)D] and PTH were determined before and after a three-week rehabilitation treatment at Bad Gastein (1000 m above sea level). At the first examination, serum 25(OH)D was median (25th, 75th percentile) 15.5 ng mL-1 (10.0 ng mL-1, 20.6 ng mL-1). Thirteen patients (18%) had a 25(OH)D concentration below 8 ng mL-1. In 53 patients (73%) the level was below 20 ng mL-1. After the sojourn, 25(OH)D significantly (p = 0.02) increased to 19.7 (11.3, 24.6) ng mL-1. PTH did not change significantly, being 32 (22.4, 43.9) pg mL-1 before and 30.3 (24.1, 39.9) pg mL-1 after the sojourn. Analysing different periods of sojourn, a significant (p < 0.001) increase in 25(OH)D was found in April but not in the other months. Patients with ankylosing spondylitis may have extremely low levels of 25(OH)D. The results of the present study suggest that a sojourn at high altitude in early spring is liable to reduce vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Altitude; Austria; Female; Hospitals, Special; Humans; Male; Middle Aged; Parathyroid Hormone; Seasons; Spondylitis, Ankylosing; Treatment Outcome; Ultraviolet Therapy; Vitamin D Deficiency

To study the prevalence of hypovitaminosis D, the effect of vitamin D supplementation on serum 25-hydroxyvitamin D [S-25(OH)D], and the intakes of vitamin D and calcium in Finnish 9- to 15-year-old athletic and nonathletic girls.. 1-year follow-up study (February 1997-March 1998) with three months of vitamin D supplementation (10 microg/d) from October to January.. Turku University Central Hospital, Finland.. 191 female volunteers aged 9-15 y (131 athletes and 60 controls).. Vitamin D and calcium intakes were estimated by a four-day food recording and a semi-quantitative food frequency questionnaire (FFQ). S-25(OH)D was followed by radioimmunoassay (RIA).. At baseline the mean S-25(OH)D concentration was 33.9 nmol/l among all girls. In winter severe hypovitaminosis D (S-25(OH)D < 20 nmol/l) occurred in 13.4% of the participants and in 67.7% S-25(OH)D was below 37.5 nmol/l. By the next summer the mean S-25(OH)D concentration was 62.9 nmol/l and in 1.6% of the subjects it was below 37.5 nmol/l. The prevalence of severe hypovitaminosis D was not significantly reduced by three months of vitamin D (10 microg/d) supplementation. At baseline, the mean intake of vitamin D was 2.9 microg/d by food recording and 4.3 microg/d by FFQ. The mean calcium intake was 1256 mg/d and 1580 mg/d, respectively. The intakes of vitamin D and calcium remained unchanged during the follow-up period. The athletes consumed more calcium than nonathletic controls, whereas the intake of vitamin D was quite similar among both groups. The vitamin D intake by FFQ correlated with the S-25(OH)D concentration in wintertime (r = 0.28, P < 0.01).. Hypovitaminosis D is fairly common in growing Finnish girls in the wintertime, and three months of vitamin D supplementation with 10 microg/d was insufficient in preventing hypovitaminosis D. The daily dietary vitamin D intake was insufficient (< 5 microg/d) in the majority of participants, while the calcium intake was usually sufficient.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcium; Child; Diet Records; Female; Finland; Follow-Up Studies; Humans; Prevalence; Radioimmunoassay; Seasons; Sports; Surveys and Questionnaires; Vitamin D; Vitamin D Deficiency

Serum 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, and alkaline phosphatase activities were measured from birth to 6-9 mo of age in 60 healthy neonates to assess the effectiveness and potential toxicity of three intermittent oral doses of cholecalciferol. Two weeks after a first dose of 15, 5, or 2.5 mg, 25(OH)D concentrations reached 307 +/- 160, 150 +/- 55, and 92 +/- 42 nmol/L, respectively. Prolonged vitamin D overload, up to 6 mo, was found in 50% of the children given 15 mg, but not in the other infants. Serum calcium transiently increased 2 wk after 15 mg but not after the lower doses. Oral doses of 2.5 mg given every 3 mo appear to provide the best protection against vitamin D deficiency and vitamin D overload in high-risk infant populations that are unsuitable for daily vitamin D supplementation.

Topics: 25-Hydroxyvitamin D 2; Administration, Oral; Alkaline Phosphatase; Calcifediol; Calcium; Cholecalciferol; Dose-Response Relationship, Drug; Drug Administration Schedule; Humans; Infant, Newborn; Longitudinal Studies; Phosphorus; Vitamin D Deficiency

To monitor ultraviolet B light exposure in human milk-fed infants both with and without supplemental vitamin D2, and to measure longitudinally the bone mineral content, growth, and serum concentrations of calcium, phosphorus, 25-hydroxyvitamin D3, 25-hydroxyvitamin D2, 1,25-dihydroxyvitamin D, and parathyroid hormone.. Longitudinal, randomized, double-blind, placebo-controlled study of 6 months' duration.. Patients from private pediatric practice, Madison, Wisconsin.. Sequential sampling of 46 human milk-fed white infants; 24 received 400 IU/day of vitamin D2, and 22 received placebo. An additional 12 patients were followed who received standard infant formula. Eighty-three percent of patients completed a full 6 months of the study.. Ultraviolet B light exposure and measurements of growth did not differ between groups. At 6 months, the human milk groups did not differ significantly in bone mineral content or serum concentrations of parathyroid hormone or 1,25-dihydroxyvitamin D, although total 25-hydroxyvitamin D values were significantly less in the unsupplemented human milk group (23.53 +/- 9.94 vs 36.96 +/- 11.86 ng/ml; p less than 0.01). However, 25-hydroxyvitamin D3 serum concentrations were significantly higher in the unsupplemented human milk-fed group compared with the supplemented group (21.77 +/- 9.73 vs 11.74 +/- 10.27 ng/ml, p less than 0.01) by 6 months of age.. Unsupplemented, human milk-fed infants had no evidence of vitamin D deficiency during the first 6 months of life.

Topics: 25-Hydroxyvitamin D 2; Bone and Bones; Breast Feeding; Calcifediol; Calcitriol; Calcium; Double-Blind Method; Environmental Exposure; Ergocalciferols; Female; Growth; Humans; Infant, Newborn; Male; Minerals; Parathyroid Hormone; Phosphorus; Random Allocation; Ultraviolet Rays; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Female; Humans; Ligands; Pregnancy; Pregnant Women; Prevalence; Vitamin D; Vitamin D Deficiency; Vitamins

To study the intake and sources of vitamin D and determinants of serum 25-hydroxyvitamin D (S-25(OH)D) in Finnish adolescents.. We studied 265 adolescents (117 girls) aged 15-17 years attending 8-year examinations of the PANIC Study, assessed diet using food records and other lifestyle factors by questionnaires, and analyzed S-25(OH)D by chemiluminescence immunoassay and determinants of S-25(OH)D using multivariate linear regression.. Mean (standard deviation) of total vitamin D intake from food and supplements was 19.2 (13.1) µg/d, and that of dietary vitamin D intake was 9.9 (5.4) µg/d. Milk fortified with vitamin D was the main dietary source of vitamin D, providing 45% of daily intake. Altogether, 29% of the adolescents used no vitamin D supplements and 25% did not meet the recommended total vitamin D intake of 10 µg/d. Mean (standard deviation) of S-25(OH)D was 62.0 (18.8) nmol/l, and S-25(OH)D was < 50 nmol/l in 29.5% of the adolescents. Vitamin D intake from supplements was the main determinant of S-25(OH)D (β = 0.465, p < 0.001), followed by consumption of milk products (β = 0.251, p < 0.001), consumption of meat products (β = 0.179, p = 0.002), travels to sunny countries (β = 0.178, p = 0.002), and average daylight time (β = 0.162, p = 0.004).. Most of the adolescents had vitamin D intake at the recommended level, although a fourth did not meet the recommended total vitamin D intake of 10 µg/d and almost a third had S-25(OH)D < 50 nmol/l. More attention should be paid to the sufficient intake of vitamin D in adolescents who do not use vitamin D supplements or fortified milk products.. ClinicalTrials.gov: NCT01803776, registered March 3, 2013.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Dietary Supplements; Female; Finland; Humans; Seasons; Vitamin D; Vitamin D Deficiency; Vitamins

We aimed to describe the vitamin D status and its distribution in different age groups, sexes, seasons, and provinces of a large Chinese population.. This study retrospectively analyzed 1,528,685 results of serum 25-hydroxyvitamin D (25(OH)D) in the central laboratory of KingMed Diagnostics. The samples were from the individuals aged 0-119 years old in 30 provinces of China. Serum 25(OH)D was measured by an accurate commercial liquid chromatography-tandem mass spectrometry (LC-MS/MS) method from January 2017 to December 2019. The subjects were stratified by age, sex, the season of blood collection, and the province of residence.. The median 25(OH)D concentration was 25.5 ng/mL (interquartile range (IQR) 18.7-32.7 ng/mL) in males and 20.8 ng/mL (IQR 14.4-28.2 ng/mL) in females. Overall, the median 25(OH)D concentration decreased with age in both males and females. Males had a 0.2-2.4 ng/mL higher median 25(OH)D concentration than females in different age groups. Vitamin D deficiency (25(OH)D < 15 ng/mL for the individuals under 14 years old; < 20 ng/mL for the individuals over 14 years old) was found in 21.3% of males and 43.6% of females. Significant seasonal variation of serum 25(OH)D concentrations was repeatedly observed in 3 years, with median concentration higher in summer (25.3 ng/mL (IQR 19.3-31.9 ng/mL)) and lower in winter (18.5 ng/mL (IQR 12.3-26.6 ng/mL)). Vitamin D status varied by province. The median 25(OH)D concentration was the highest in Hainan (31.0 ng/mL (IQR 24.9-39.2 ng/mL)) and the lowest in Qinghai (14.4 ng/mL (IQR 9.6-20.0 ng/mL)). 25(OH)D. In China, vitamin D deficiency is prevalent in the population participating in clinical vitamin D measurement. Age and sex differences in vitamin D levels were observed in our study. Seasonal variation and provincial differences are important aspects of serum vitamin D status. 25(OH)D

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Calcifediol; Child; Child, Preschool; Chromatography, Liquid; East Asian People; Female; Humans; Infant; Infant, Newborn; Male; Middle Aged; Retrospective Studies; Seasons; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency; Vitamins; Young Adult

Despite an increasing interest in vitamin D status, a reference range of the nutrient has not been fully established. This is partly due to a paucity of standardized measuring systems with high throughput. In addition, the range may vary by populations and may change with modernization of lifestyles.. This study aims to calculate the current reference concentration of 25-hydroxyvitamin D (25(OH)D) among healthy people living in an urban area in Japan.. A newly developed fully automated liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) system was used to measure serum 25(OH)D concentrations. Reproducibility was assessed by measuring standardized samples. Accuracy was validated by comparing with commercially available immunoassays. Then, mass screening was conducted targeting participants who received medical checkups in Tokyo from April 2019 to March 2020, and the reference ranges were calculated.. The high prevalence of vitamin D insufficiency among seemingly healthy population may be attributed to lifestyle characteristics of people living in urban areas of Japan, including spending less time outdoors and lower intake of traditional foods. Longitudinal follow-up and mass screenings targeting different population will help elucidate reasons for discrepancies between official guidelines and the observed concentrations, to which the well-validated measurement system is essential.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Chromatography, Liquid; East Asian People; Female; Humans; Japan; Male; Reference Values; Reproducibility of Results; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency; Vitamins

Vitamin D plays an important role not only in bone health but also in many other body functions. Vitamin D deficiency is very common in the general population. Measurement of blood 25-hydroxyvitamin D is a common practice to evaluate vitamin D deficiency. Immunoassays and liquid chromatography tandem mass spectrometry (LC-MS/MS) are the most commonly used methods for the measurement of 25-hydroxyvitamin D. Immunoassays suffer from specificity issues and do not distinguish between 25-hydroxyvitamin D2 and D3. Therefore, LC-MS/MS is a preferred method for quantification of 25-hydroxyvitamin. We describe an LC-MS/MS method, which involves protein precipitation and analysis of the extract using atmospheric pressure chemical ionization and multiple reaction monitoring. 25-hydroxyvitamin D3-d6 is used as an internal standard. The method is linear from 1-100 ng/mL for both 25-hydroxyvitamin D2 and D3 and has imprecision of <10%.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Chromatography, Liquid; Humans; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency

Vitamin D is critical for calcium and bone metabolism. Vitamin D insufficiency impairs skeletal mineralization and bone growth rate during childhood, thus affecting height and health. Vitamin D status in children with short stature is sparsely reported. The purpose of the current study was to investigate various vitamin D components by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) to better explore vitamin D storage of short-stature children. Serum circulating levels of 25-hydroxyvitamin D2 [25(OH)D2], 25-hydroxyvitamin D3 [25(OH)D3], and 3-epi-25-hydroxyvitamin D3 [3-epi-25(OH)D3, C3-epi] were accurately computed using the LC-MS/MS method. Total 25(OH)D [t-25(OH)D] and ratios of 25(OH)D2/25(OH)D3 and C3-epi/25(OH)D3 were then respectively calculated. Free 25(OH)D [f-25(OH)D] was also measured.. 25(OH)D3 and f-25(OH)D levels in short-stature subgroups 2 (school age: 7~12 years old) and 3 (adolescence: 13~18 years old) were significantly lower compared with those of healthy controls. By contrast, C3-epi levels and C3-epi/25(OH)D3 ratios in all the three short-stature subgroups were markedly higher than the corresponding healthy cases. Based on cutoff values developed by Endocrine Society Recommendation (but not suitable for methods 2 and 3), sufficient storage capacities of vitamin D in short-stature subgroups 1, 2, and 3 were 42.8%, 23.8%, and 9.0% as determined by Method 3 [25(OH)D2/3+25(OH)D3], which were lower than those of 57.1%, 28.6%, and 18.2% as determined by Method 1 [25(OH)D2+25(OH)D3+C3-epi] and 45.7%, 28.5%, and 13.6% as determined by Method 2 [25(OH)D2/3+25(OH)D3+C3-epi]. Levels of 25(OH)D2 were found to be weakly negatively correlated with those of 25(OH)D3, and higher 25(OH)D3 levels were positively correlated with higher levels of C3-epi in both short-stature and healthy control cohorts. Furthermore, f-25(OH)D levels were positively associated with 25(OH)D3 and C3-epi levels in children.. The current LC-MS/MS technique can not only separate 25(OH)D2 from 25(OH)D3 but also distinguish C3-epi from 25(OH)D3. Measurement of t-25(OH)D [25(OH)D2+25(OH)D3] alone may overestimate vitamin D storage in children, and short-stature children had lower vitamin D levels compared with healthy subjects. Ratios of C3-epi/25(OH)D3 and 25(OH)D2/25(OH)D3 might be alternative markers for vitamin D catabolism/storage in short-stature children. Further studies are needed to explore the relationships and physiological roles of various vitamin D metabolites.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Biomarkers; Body Height; Calcifediol; Case-Control Studies; Child; Chromatography, High Pressure Liquid; Dwarfism; Female; Follow-Up Studies; Growth Disorders; Humans; Male; Prognosis; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency; Vitamins

Vitamin D deficiency is prevalent globally and there is lack of evidence as to how 25(OH)D2 contributes to vitamin D status. The aim of this study was to describe vitamin D status and to assess the role of vitamin D2, a dietary vitamin D source, against the vitamin D status of children aged 3-5 years in China.. Data were extracted from the Chinese National Nutrition and Health Surveillance (CNNHS) in 2013. The concentration of serum 25(OH)D2 and 25(OH)D3 was measured by using LC-MS/MS.. A total of 1435 subjects were enrolled and serum 25(OH)D were analyzed. The prevalence of total serum 25(OH)D < 30 nmol/L was 8.9%. Serum 25(OH)D2 was detected in 10.9% of the studied children. After adjusting for confounding factors, total 25(OH)D concentration was 8.48 nmol/L lower and odds ratio of vitamin D deficiency was 4.20 times (OR (95%CI): 4.20 (1.64, 10.77)) in children without 25(OH)D2 than those with 25(OH)D2 detected.. Vitamin D deficiency was common among children aged 3-5 years in China. Vitamin D2 may play a role in preventing vitamin D deficiency in Chinese children aged 3-5 years.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child, Preschool; China; Chromatography, Liquid; Female; Humans; Male; Nutrition Surveys; Nutritional Status; Population Surveillance; Prevalence; Tandem Mass Spectrometry; Vitamin D Deficiency

To investigate the association of VitD with GDM, and examine the potential modifying effect of prepregnancy BMI in Chinese pregnant women.. 3318 pregnant women underwent oral glucose tolerance test (OGTT) were selected from Zhoushan Pregnant Women Cohort. Plasma VitD levels were measured in the first (T1) and/or second trimester (T2). Multiple linear and logistic regression models were used for evaluating the association of VitD with GDM.. Prepregnancy BMI was positively associated with all three time-point glucose of OGTT. 25(OH)D level in T1 (β = -0.003) and T2 (β = -0.004), and its change from T1 to T2 (β = -0.004) were significantly and inversely associated with fasting blood glucose (FBG) of OGTT, but not 1-h and 2-h postload blood glucose of OGTT, respectively. The negative associations of VitD and FBG were stronger among overweight/obese women. VitD deficiency (25(OH)D < 20 ng/ml) in T2 was associated with an increased risk of GDM with increased FBG, GDM subtype 1 (OR: 2.10) and subtype 3 (OR: 2.19). Moreover, prepregnancy BMI modified this effect on GDM subtype 1 (BMI < 24: OR = 1.42; BMI ≥ 24: OR = 9.61, P for interaction = 0.002). Lower VitD increment from T1 to T2 was associated with a higher risk for GDM among overweight/obese women. Additionally, GDM prevalence fluctuated with the season, i.e. lower in summer/fall and higher in winter/spring.. Maternal VitD deficiency was associated with a higher risk of GDM subtype with increased FBG, and the risk is much greater among overweight/obesity women. The lower the VitD increment during pregnancy, the greater the risk of GDM, especially in overweight/obesity women. Furthermore, seasonal variation of GDM may be exhibited as a critical confounder in the association of VitD and GDM.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Blood Glucose; Body Mass Index; Calcifediol; Diabetes, Gestational; Fasting; Female; Glucose Tolerance Test; Humans; Obesity; Pregnancy; Pregnancy Trimesters; Prospective Studies; Risk Assessment; Risk Factors; Seasons; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cohort Studies; Female; Greece; Humans; Infant, Newborn; Infant, Newborn, Diseases; Male; Pregnancy; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Betacoronavirus; Coronavirus Infections; COVID-19; Disease Progression; Humans; Male; Pandemics; Pneumonia, Viral; Respiratory Distress Syndrome; Risk Factors; SARS-CoV-2; Severity of Illness Index; Vitamin D Deficiency

Background Recent research has indicated that vitamin D may have immune supporting properties through modulation of both the adaptive and innate immune system through cytokines and regulation of cell signalling pathways. We hypothesize that vitamin D status may influence the severity of responses to Covid-19 and that the prevalence of vitamin D deficiency in Europe will be closely aligned to Covid-19 mortality. Methods We conducted a literature search on PubMed (no language restriction) of vitamin D status (for older adults) in countries/areas of Europe affected by Covid-19 infection. Countries were selected by severity of infection (high and low) and were limited to national surveys or where not available, to geographic areas within the country affected by infection. Covid-19 infection and mortality data was gathered from the World Health Organisation. Results Counter-intuitively, lower latitude and typically 'sunny' countries such as Spain and Italy (particularly Northern Italy), had low mean concentrations of 25(OH)D and high rates of vitamin D deficiency. These countries have also been experiencing the highest infection and death rates in Europe. The northern latitude countries (Norway, Finland, Sweden) which receive less UVB sunlight than Southern Europe, actually had much higher mean 25(OH)D concentrations, low levels of deficiency and for Norway and Finland, lower infection and death rates. The correlation between 25(OH)D concentration and mortality rate reached conventional significance (P=0.046) by Spearman's Rank Correlation. Conclusions Optimising vitamin D status to recommendations by national and international public health agencies will certainly have benefits for bone health and potential benefits for Covid-19. There is a strong plausible biological hypothesis and evolving epidemiological data supporting a role for vitamin D in Covid-19.

Topics: 25-Hydroxyvitamin D 2; Betacoronavirus; Comorbidity; Coronavirus Infections; COVID-19; Dietary Supplements; Europe; Health Policy; Humans; Inflammation; Pandemics; Pneumonia, Viral; Prevalence; SARS-CoV-2; Severity of Illness Index; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency (VDD) is a global public health problem. Inaccurate methods for measuring plasma 25-hydroxyvitamin D (25[OH]D) may have contributed to the reported high prevalence of VDD. We hypothesized that the most commonly used assay for vitamin D status, chemiluminescence immunoassay (CLIA), underestimates 25(OH)D levels and thus overestimates VDD. Using both liquid chromatography-tandem mass spectrometry and CLIA for plasma 25(OH)D, we evaluated the prevalence of VDD in adolescents (11-16 years-old; n = 410) by both methods in a cross-sectional study. Subjects were selected from public middle schools from all the 6 Governorates of Kuwait using stratified multistage cluster random sampling. Cohen κ agreement, linear regression, and Bland-Altman plots were used to evaluate the classification of VDD by the 2 methods. VDD (25[OH]D < 50 nmol/L) was 85.9% with CLIA and 81.2% with liquid chromatography-tandem mass spectrometry. There was a good agreement between the 2 methods in classifying the study subjects as deficient, insufficient, or sufficient (κ = 85.1%, P < .001). The between-assay bias was very small with a mean percentage difference < 1% from the mean value of the 25(OH)D as assessed by the 2 methods. These data did not support our hypothesis, and we conclude that the routine methods used for plasma 25(OH)D levels have no or little impact on evaluating VDD as a public health problem or in clinical management.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Child; Chromatography, Liquid; Cross-Sectional Studies; Female; Humans; Kuwait; Linear Models; Luminescent Measurements; Male; Prevalence; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency

While vitamin D insufficiency is known to impact a multitude of health outcomes, including HIV-1, little is known about the role of vitamin D-mediated immune regulation in the female reproductive tract (FRT). We performed a pilot clinical study of 20 women with circulating 25(OH)D levels <62.5 nmol/L. Participants were randomized into either weekly or daily high-dose oral vitamin D supplementation groups. In addition to serum vitamin D levels, genital mucosal endpoints, including soluble mediators, immune cell populations, gene expression, and ex vivo HIV-1 infection, were assessed. While systemic vitamin D levels showed a significant increase following supplementation, these changes translated into modest effects on the cervicovaginal factors studied. Paradoxically, post-supplementation vitamin D levels were decreased in cervicovaginal fluids. Given the strong correlation between vitamin D status and HIV-1 infection and the widespread nature of vitamin D deficiency, further understanding of the role of vitamin D immunoregulation in the female reproductive tract is important.

Topics: 25-Hydroxyvitamin D 2; Adult; Dietary Supplements; Disease Susceptibility; Female; Genitalia, Female; HIV Infections; HIV-1; Humans; Immunologic Factors; Middle Aged; Mucous Membrane; Nutritional Status; Pilot Projects; Vitamin D; Vitamin D Deficiency; Young Adult

Previous observational studies have suggested that low vitamin D status is associated with high circulating C-reactive protein levels, as well as other plasma inflammatory cytokines. However, there is no study to explore the relationship between vitamin D status and Lp-PLA2, a new biomarker of vascular-specific inflammation. The aim of this study was to examine the association between vitamin D status and circulating Lp-PLA2 levels in subjects with type 2 diabetes mellitus.. This descriptive cross-sectional study enrolled diabetic subjects who underwent physical examination at Taizhou People's Hospital between August 2016 and January 2017. Blood pressure, anthropometry, metabolic profiles, serum 25(OH)D levels and Lp-PLA2 mass levels were measured in all participants.. A total of 196 participants were recruited into this study. The vitamin D insufficiency group had higher serum LP-PLA2 levels than the vitamin D sufficiency group (t=-2.765, p=.005). A significant negative correlation was noted between Lp-PLA2 and 25(OH)D in the vitamin D insufficiency group (r=-0.364, p=0.009). However, no significant relationship between serum Lp-PLA2 concentration and 25(OH)D levels was observed in subjects with vitamin D sufficiency.. From this cohort of patients with type 2 diabetes, regardless of traditional cardiovascular risk factors, we observed a statistically significant inverse relation between Lp-PLA2 and 25(OH)D at levels <30ng/mL.

Topics: 1-Alkyl-2-acetylglycerophosphocholine Esterase; 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Apolipoprotein A-I; Apolipoproteins B; Biomarkers; Blood Glucose; Body Mass Index; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Fasting; Female; Humans; Male; Middle Aged; Regression Analysis; Risk Factors; Vitamin D; Vitamin D Deficiency; Young Adult

To investigate the correlation of serum vitamin A, D, and E levels with a recurrent respiratory infection (RRI) in children.. The medical records of 422 children with RRI (a study group) in Cangzhou Central Hospital from January 2015 to December 2018 were retrospectively analyzed (the study group was divided into an active group and a stable group). Further 100 healthy children who underwent physical examination at the same time were enrolled as a control group. High-performance liquid chromatography (HPLC) was used to determine vitamin A, D, and E levels, so as to analyze their differences between the groups.. Vitamin A, D, and E in the active and stable groups were significantly lower than those in the control group (p < 0.001); in the active group they were significantly lower than those in the stable group (p < 0.001). According to partial correlation analysis, in children with active RRI, vitamin A was respectively positively correlated with vitamin D (r=0.945, p < 0.001), and vitamin E (r=0.988, p < 0.001). Moreover, vitamin E was positively correlated with vitamin D (r=0.959, p < 0.001).. The deficiency of vitamin A, D, and E is positively correlated with the disease activity of children with RRI. Therefore, the supplement of vitamin A, D, and E through dietary adjustment is beneficial to the rehabilitation of the children.

Topics: 25-Hydroxyvitamin D 2; Case-Control Studies; Child, Preschool; China; Chromatography, High Pressure Liquid; Female; Humans; Infant; Male; Recurrence; Respiratory Tract Infections; Retrospective Studies; Vitamin A; Vitamin A Deficiency; Vitamin D Deficiency; Vitamin E; Vitamin E Deficiency

Vitamin D affects multiple body functions through the regulation of gene expression. In sports medicine, its influence on musculoskeletal health and performance is of particular interest. Vitamin D insufficiency might decrease athletic performance and increase the risk of musculoskeletal injuries. Several studies have demonstrated vitamin D deficiency in professional athletes; however, the prevalence of vitamin D insufficiency in professional handball players is yet unknown.. The study was planned as a prospective, non-interventional study. We examined 70 male elite handball athletes (first league) in a pre-competition medical assessment in July. Age, height, weight, body mass index, 25-OH vitamin D, calcium, and parathyroid hormone were evaluated, and a sun exposure score was calculated. Players were then divided into two groups of vitamin D levels: insufficient (<30 ng/mL) and sufficient (≥30 ng/mL).. The mean 25-OH vitamin D level of the 70 players was 33.5 ± 10.9 ng/mL (median 32.2, IQR 26.5-38.9 ng/mL). Thirty-nine (55.7%) had sufficient and 31 (44.3%) insufficient levels. Athletes with sufficient vitamin D levels had significantly lower parathyroid hormone levels than athletes with insufficiency (24.9 ± 12.1 vs. 33.5 ± 15.1 ng/mL, p = 0.02). All other parameters evaluated demonstrated no significant difference between the two groups.. Vitamin D insufficiency is a common finding in professional handball athletes even in summer, which might negatively affect physical performance. Furthermore, it might lead to an increased risk of musculoskeletal injuries and infections. This should be evaluated in further studies.

Topics: 25-Hydroxyvitamin D 2; Adult; Athletic Performance; Body Mass Index; Calcium; Germany; Humans; Male; Musculoskeletal System; Parathyroid Hormone; Prevalence; Prospective Studies; Respiratory Tract Infections; Risk Factors; Seasons; Sports; Vitamin D Deficiency; Young Adult

Topics: 25-Hydroxyvitamin D 2; Aged, 80 and over; Dietary Supplements; Elder Nutritional Physiological Phenomena; Europe; Female; Geriatric Assessment; Humans; Male; Nursing Homes; Nutritional Requirements; Vitamin D Deficiency

Inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease have been linked to vitamin D-deficiency. Using a dextran sodium sulphate (DSS)-induced model of IBD we have shown previously that mice raised on vitamin D-deficient diets from weaning have lower serum 25-hydroxyvitamin D (25OHD) levels and develop more severe colitis compared to vitamin D-sufficient counterparts. We have also shown in vitro that immune responses to 25OHD may depend on 'free' rather than total serum concentrations of 25OHD. To investigate the possible effects of free versus total 25OHD on anti-inflammatory immune responses in vivo we have studied DSS-induced colitis in wild type C57BL/6 mice raised from weaning on diets containing vitamin D2 (D2) or vitamin D3 (D3) only (both 1000 IU/kg feed). 25OHD2 has lower binding affinity for the vitamin D binding protein than 25OHD3 which results in higher levels of free 25OHD2 relative to free 25OHD3 in mice raised on a D2-only diet. Total serum 25OHD concentrations, measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS), showed that D2 mice had significantly lower levels of 25OHD than D3 mice (6.85 ± 2.61 nmol/L vs. 49.16 ± 13.8 nmol/L for D2 and D3 respectively). Despite this, direct ELISA measurement showed no difference in free serum 25OHD levels between D2 and D3 mice (13.62 ± 2.26 pmol/L vs. 14.11 ± 2.24 pmol/L for D2 and D3 respectively). Analysis of DSS-induced colitis also showed no difference in weight loss or disease progression between D2 and D3 mice. These data indicate that despite D2-fed mice being vitamin D-deficient based on serum total 25OHD concentrations, these mice showed no evidence of increased inflammatory colitis disease relative to vitamin D-sufficient D3 mice. We therefore propose that free, rather than total serum 25OHD, may be a better marker of immune responses to vitamin D in vivo.

Topics: 25-Hydroxyvitamin D 2; Animals; Calcifediol; Cholecalciferol; Colitis; Ergocalciferols; Male; Mice, Inbred C57BL; Vitamin D; Vitamin D Deficiency; Vitamins

To prospectively and longitudinally investigate vitamin D status during early to mid-pregnancy in relation to gestational diabetes mellitus (GDM) risk.. In a nested case-control study of 107 GDM cases and 214 controls within the Fetal Growth Studies-Singleton Cohort, plasma levels of 25-hydroxyvitamin D2 and D3 (25(OH)D) and vitamin D binding protein were measured at gestational weeks 10 to 14, 15 to 26, 23 to 31, and 33 to 39; we further calculated total, free, and bioavailable 25(OH)D. Conditional logistic regression models and linear mixed-effects models were used.. We observed a threshold effect for the relation of vitamin D biomarkers with GDM risk. Vitamin D deficiency (<50 nmol/L) at 10 to 14 gestational weeks was associated with a 2.82-fold increased risk for GDM [odds ratio (OR) = 2.82, 95% confidence interval (CI): 1.15-6.93]. Women with persistent vitamin D deficiency at 10 to 14 and 15 to 26 weeks of gestation had a 4.46-fold elevated risk for GDM compared with women persistently non-deficient (OR = 4.46, 95% CI: 1.15-17.3).. Maternal vitamin D deficiency as early as the first trimester of pregnancy was associated with an elevated risk of GDM. The association was stronger for women who were persistently deficient through the second trimester. Assessment of vitamin D status in early pregnancy may be clinically important and valuable for improving risk stratification and developing effective interventions for the primary prevention of GDM.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Case-Control Studies; Diabetes, Gestational; Female; Humans; Logistic Models; Longitudinal Studies; Odds Ratio; Pregnancy; Pregnancy Complications; Pregnancy Trimester, First; Risk Factors; Vitamin D Deficiency; Vitamin D-Binding Protein; Young Adult

To characterize the physiological changes in 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH). The prevalence of vitamin D inadequacy varied significantly according to the adopted criteria. There was a seasonal variation of 25(OH)D during pregnancy. The women with insufficient vitamin D status present greater longitudinal increases in the concentrations of 1,25(OH)

Topics: 25-Hydroxyvitamin D 2; Adult; Brazil; Calcifediol; Calcitriol; Cohort Studies; Diet; Dietary Supplements; Ergocalciferols; Female; Humans; Longitudinal Studies; Maternal Nutritional Physiological Phenomena; Pregnancy; Pregnancy Complications; Prevalence; Prospective Studies; Seasons; Self Report; Vitamin D; Vitamin D Deficiency; Young Adult

Gestational vitamin D insufficiency is related with increased risks of various diseases and poor health outcomes later in life. Telomere length at birth or early in life is known to be a predictor of individual health. Both vitamin D and telomere length are related with various health conditions, and vitamin D concentrations are associated with leukocyte telomere lengths in women. We investigated the association between maternal vitamin D concentrations and newborn leukocyte telomere lengths. This cross-sectional study included 106 healthy pregnant women without adverse obstetric outcomes and their offspring. We examined the maternal age, weight before pregnancy, health behaviours, and nutritional intakes, along with each newborn's sex and birthweight, and we measured maternal height, telomere length, total white blood cell count, and glycosylated haemoglobin as covariates. Pearson's correlation coefficients were calculated to evaluate the relationship between the baseline variables and newborn leukocyte telomere lengths. To confirm that there was an independent association between newborn leukocyte telomere lengths and maternal vitamin D concentrations, we performed a stepwise multiple linear regression analysis. Newborn leukocyte telomere lengths correlated positively with maternal leukocyte telomere lengths (r = .76, p < .01), maternal 25-hydroxyvitamin D concentrations (r = .72, p < .01), maternal energy intakes (r = .22, p = .03), and newborn body weights (r = .51, p < .01). In the multivariate model, newborn leukocyte telomere lengths were associated with maternal vitamin D concentrations (β = .33, p < .01). These findings suggest that the maternal vitamin D concentration during pregnancy may be a significant determinant of the offspring's telomere length.

Topics: 25-Hydroxyvitamin D 2; Birth Weight; Calcifediol; Cross-Sectional Studies; Female; Fetal Blood; Humans; Infant, Newborn; Leukocytes; Male; Maternal Nutritional Physiological Phenomena; Multivariate Analysis; Nutritional Status; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Third; Prevalence; Republic of Korea; Severity of Illness Index; Telomere Shortening; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency is associated with wide range of pathologies. Some evidences have shown that low vitamin D circulating levels in children and adolescent are related to fat mass and obesity. The objectives of the present study were to characterize vitamin D status in children and adolescents and to determine if serum 25-hydroxyvitamin D (25(OH)D) concentration is related to adiposity assessed by body mass index (BMI). Serum 25(OH)D levels were measured by LIAISON method in 471 children and adolescents (2 to 18 years age) and analyzed according to gender, pubertal period, age, and BMI. An overall prevalence of 25(OH)D insufficiency and deficiency was present in the 67.1%. Lower 25(OH)D levels were found in females (25.56 ± 14.03 vs 29.71 ± 17.10 ng ml

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adolescent; Body Mass Index; Calcifediol; Child; Child Development; Child Nutritional Physiological Phenomena; Child, Preschool; Cross-Sectional Studies; Female; Health Transition; Hospitals, University; Humans; Male; Nutritional Status; Overweight; Pediatric Obesity; Prevalence; Risk Factors; Severity of Illness Index; Sex Factors; Spain; Vitamin D Deficiency

Celiac disease (CD) is an autoimmune disorder characterized by damage to the intestinal mucosa and nutrient malabsorption in severe cases. However, it remains unclear whether nutrient deficiencies and other adverse health effects are prevalent in individuals with positive CD serology identified through screening studies.. The objective was to determine whether biomarkers of cardiometabolic health and nutritional status differ between those with positive and negative CD serology identified in a screening study of Canadian adults.. Participants ( n=2832) were from the Toronto Nutrigenomics and Health Study and the Toronto Healthy Diet Study. Individuals were screened for CD-specific anti-tissue transglutaminase autoantibodies. Lipid profiles as well as concentrations of six carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, and zeaxanthin), three tocopherols (α-tocopherol, δ-tocopherol, and γ-tocopherol), retinol, ascorbic acid, and 25-hydroxyvitamin D were cross-sectionally compared between those with positive and negative CD serology using general linear mixed models.. Individuals with positive CD serology ( n=23) had significantly lower levels of HDL-cholesterol ( p=0.008) and apolipoprotein-AI ( p=0.02), a higher ratio of total cholesterol to HDL-cholesterol ( p=0.006), and a higher apolipoprotein-B/AI ratio ( p=0.03) than those with negative CD serology. Positive CD serology was also associated with significantly lower concentrations of retinol ( p=0.006) in fully adjusted models. Those with positive CD serology had lower serum 25-hydroxyvitamin D in unadjusted models ( p=0.01), but not in fully adjusted models ( p=0.08).. Individuals with undiagnosed CD may have unfavorable lipid profiles and be at elevated risk for inadequacy of certain fat-soluble vitamins, but not widespread nutrient deficiencies.

Topics: 25-Hydroxyvitamin D 2; Adult; Asymptomatic Diseases; Autoantibodies; Biomarkers; Calcifediol; Cardiovascular Diseases; Celiac Disease; Cross-Sectional Studies; Female; Humans; Male; Malnutrition; Mass Screening; Nutritional Status; Ontario; Risk; Severity of Illness Index; Transglutaminases; Vitamin A; Vitamin A Deficiency; Vitamin D Deficiency

To measure total 25-hydroxyvitamin D levels in women in mid-pregnancy who participated in the Belfast centre of the Hyperglycaemia and Adverse Pregnancy Outcome (HAPO) observational study, and to investigate the associations between levels of 25-hydroxyvitamin D and markers of gestational diabetes mellitus and lipid biomarkers.. A total of 1585 pregnant women had serum samples available for measurement. Participants were recruited from the Royal Jubilee Maternity Hospital, Belfast, Northern Ireland, at 24-32 weeks' gestation, as part of the HAPO study. 25-hydroxyvitamin D concentrations were measured using liquid chromatography tandem mass spectrometry. Glucose, C-peptide and lipid levels were previously analysed in a central laboratory. Statistical analysis was performed.. The median (interquartile range) 25-hydroxyvitamin D concentration during pregnancy was 38.6 (24.1-60.7) nmol/l, with 65.8% of women being vitamin D-deficient (≤50 nmol/l). In regression analysis, the association between maternal 25-hydroxyvitamin D and fasting plasma glucose levels approached significance [regression coefficient -0.017 (95% CI -0.034 to 0.001); P=0.06], and a significant positive association was observed between maternal 25-hydroxyvitamin D and β-cell function [1.013 (95% CI 1.001 to 1.024); P=0.031]. Maternal 25-hydroxyvitamin D level was positively associated with HDL [0.047 (95% CI 0.021 to 0.073) P≤ 0.001] and total cholesterol [0.085 (95% CI 0.002 to 0.167); P=0.044] in regression analysis.. These results indicate a high prevalence of vitamin D deficiency during pregnancy, which requires identification and treatment; however, only weak associations were observed between 25-hydroxyvitamin D level and markers of glucose and insulin metabolism. This would suggest that these are of doubtful clinical significance.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Blood Glucose; C-Peptide; Calcifediol; Cholesterol; Chromatography, Liquid; Diabetes, Gestational; Diet; Female; Humans; Northern Ireland; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Second; Pregnancy Trimester, Third; Tandem Mass Spectrometry; Vitamin D; Vitamin D Deficiency; White People; Young Adult

Peritoneal protein loss (PPL) is associated with cardiovascular disease and mortality in peritoneal dialysis (PD). Controversial results have been published about the effect of paricalcitol in PPL among PD patients. This study intends to analyze the relationship between paricalcitol and PPL in PD.. In a retrospective study, prevalent PD patients were divided into 2 groups: "with paricalcitol" and "without paricalcitol". X2-test, Student's t test, Pearson correlation coefficient and Logistic Regression analysis were applied.. Eighty-two patients were included. PPL was lower among patients medicated with paricalcitol (5.17 ± 1.71 vs. 6.79 ± 2.10 g/24 h, p = 0.0001). In multivariate analysis, paricalcitol and dialysate/plasma ratio of creatinine (D/P creatinine) were independently related to PPL (OR 4.270 [1.437-12.684], p = 0.009 and OR 0.205 [0.064-0.659], p = 0.008, respectively), adjusted for diabetes.. Paricalcitol and D/P creatinine were independently related to PPL. Paricalcitol may have an effect on PPL in PD patients.

Topics: 25-Hydroxyvitamin D 2; Aged; Creatinine; Ergocalciferols; Female; Humans; Male; Middle Aged; Peritoneal Dialysis; Protein Deficiency; Retrospective Studies; Vitamin D Deficiency

Chronic autoimmune atrophic gastritis (CAAG) is an autoimmune disease characterized by hypo/achlorhydria. A role of CAAG in the pathogenesis of nutritional deficiencies has been reported, therefore we hypothesized a possible association between CAAG and 25-OH-Vitamin D [25(OH)D] deficiency. Aim of the present study is to evaluate the prevalence of 25(OH)D deficiency in CAAG patients.. 87 CAAG patients (71 females; mean age 63.5 ± 12.8 years) followed at our Centre from January 2012 to July 2015 were consecutively evaluated. 25(OH)D, vitamin B. Data from the present study showed a significant reduction of 25(OH)D levels in CAAG patients and a possible impairment of vitamin D absorption in CAAG may be postulated. Any implication to the genesis of gastric carcinoids remains to be elucidated.

Topics: 25-Hydroxyvitamin D 2; Aged; Autoimmune Diseases; Calcium; Chronic Disease; Female; Gastritis, Atrophic; Humans; Intestinal Absorption; Male; Middle Aged; Parathyroid Hormone; Prospective Studies; Vitamin B 12; Vitamin D Deficiency

While reports of inadequate vitamin D intakes among young children are widespread, data on the prevalence of vitamin D deficiency are inconsistent. We aimed to quantify vitamin D intake and serum 25-hydroxyvitamin D [25(OH)D] concentrations in children aged 2 years in the prospective Cork BASELINE Birth Cohort Study.. Serum 25(OH)D was analysed using UPLC-MS/MS in 741 children living in Cork, Ireland (51°N). Two-day weighed food diaries were collected in 467 children, and 294 provided both a blood sample and a food diary.. Mean (SD) 25(OH)D concentrations were 63.4 (20.4) nmol/L [winter: 54.5 (19.9), summer: 71.2 (17.5)]. The prevalence of vitamin D deficiency (<30 nmol/L) was 4.6, and 26.7% were <50 nmol/L [45.2% during winter (November-April) and 10.4% in summer (May-October)]. With a mean (SD) vitamin D intake of 3.5 (3.1) µg/day, 96% had intakes below 10 µg/day, the current IOM estimated average requirement and the SACN safe intake value for this age group. After adjustment for season, vitamin D intake (µg/day) was associated with higher 25(OH)D concentrations [adjusted estimate (95% CI) 2.5 (1.9, 3.1) nmol/L]. Children who did not consume vitamin D-fortified foods or supplements had very low vitamin D intakes (1.2 (0.9) µg/day), and during winter, 12 and 77% were <30 and <50 nmol/L, respectively, compared with 6 and 44% of fortified food consumers.. There was a high prevalence of low vitamin D status during winter, especially among children who did not consume fortified foods or nutritional supplements. Our data indicate the need for dietary strategies to increase vitamin D intakes in this age group. This report provides further evidence that DRVs for vitamin D should be based on experimental data in specific population groups and indicates the need for dose-response RCTs in young children.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child Nutritional Physiological Phenomena; Child, Preschool; Cohort Studies; Diet; Diet Records; Dietary Supplements; Female; Food, Fortified; Humans; Ireland; Longitudinal Studies; Male; Nutritional Status; Prevalence; Prospective Studies; Seasons; Vitamin D; Vitamin D Deficiency

Pregnancy is characterised by increased bone turnover, but high bone turnover with resorption exceeding formation may lead to negative maternal bone remodelling. Recent studies are conflicting regarding the effect of calcium on skeletal health in pregnancy. The aim of this study was to examine the seasonal effect of serum 25-hydroxyvitamin D (25OHD) and dietary calcium on a marker of bone resorption.. This was prospective study of 205 pregnant women [two cohorts; early pregnancy at 13 weeks (n = 96), and late pregnancy at 28 weeks (n = 109)]. Serum 25OHD and urine cross-linked N-telopeptides of type I collagen (uNTX) were measured at both time points. Intakes of vitamin D and calcium were recorded using 3-day food diaries at each trimester.. Compared to summer pregnancies, winter pregnancies had significantly lower 25OHD and significantly higher uNTX. Higher calcium intakes were negatively correlated with uNTX in winter, but not summer. In late pregnancy, compared to those reporting calcium intakes ≥1000 mg/day, intakes of <1000 mg/day were associated with a greater increase in uNTX in winter pregnancies than in summer (41.8 vs. 0.9%). Increasing calcium intake in winter by 200 mg/day predicted a 13.3% reduction in late pregnancy uNTX.. In late pregnancy, during winter months when 25OHD is inadequate, intakes of dietary calcium <1000 mg/day were associated with significantly increased bone resorption (uNTX). Additional dietary calcium is associated with reduced bone resorption in late pregnancy, with greater effect observed in winter. Further research regarding optimal dietary calcium and 25OHD in pregnancy is required, particularly for women gestating through winter.

Topics: 25-Hydroxyvitamin D 2; Biomarkers; Bone Resorption; Calcifediol; Calcium, Dietary; Cohort Studies; Collagen; Diet Records; Dietary Supplements; Female; Humans; Ireland; Maternal Nutritional Physiological Phenomena; Pregnancy; Pregnancy Complications; Pregnancy Trimester, First; Pregnancy Trimester, Third; Prospective Studies; Risk; Seasons; Severity of Illness Index; Vitamin D Deficiency

Mixed reports exist about the role of 25-hydroxyvitamin D (25(OH)D) in muscle ageing and there are few prospective studies involving the very old (aged ≥ 85) who are at highest risk of low 25(OH)D, loss of muscle mass and strength, and physical performance decline. In the Newcastle 85+ Study (

Topics: 25-Hydroxyvitamin D 2; Aged, 80 and over; Calcifediol; Cohort Studies; Dietary Supplements; Disease Progression; Elder Nutritional Physiological Phenomena; Female; Humans; Longitudinal Studies; Male; Muscle Strength; Nutritional Status; Prospective Studies; Psychomotor Performance; Risk; Sarcopenia; Seasons; Self Report; Sex Factors; United Kingdom; Vitamin D; Vitamin D Deficiency

A large number of evidence supports the role of vitamin D insufficiency in both women and men infertility. However, no studies have evaluated the rate of concordance of vitamin D status between the partners. This finding might open new scenarios in the interpretation of the available data linking vitamin D insufficiency and infertility. In the present cross-sectional study, 103 consecutive infertile couples were recruited between April and May 2014. Both partners concomitantly provided a serum sample for the assessment of 25-hydroxy-vitamin D [25-(OH)-D]. Vitamin D insufficiency was defined as serum 25-(OH)-D <20 ng/ml. One hundred-fifty subjects (73 women and 77 males) were 25-(OH)-D insufficient, corresponding to a rate of 73%. Overall, concordance was observed in 73 couples (71%), thus higher than the expected 61% (0.732 + 0.272) based on chance (p = 0.007). The Pearson coefficient of correlation R2 between the partners of the couples was 0.52 (p < 0.001). No statistically significant differences emerged when evaluating the rate of 25-(OH)-D insufficiency according to the causes of infertility. Serum 25-(OH)-D correlates within the partners of infertile couples. Further evidence is warranted to determine the clinical relevance and possible clinical applications of this finding.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cross-Sectional Studies; Family Characteristics; Family Health; Female; Humans; Incidence; Infertility, Female; Infertility, Male; Italy; Male; Nutritional Status; Seasons; Severity of Illness Index; Vitamin D Deficiency; Young Adult

We investigated associations between serum 25-hydroxyvitamin D (25(OH)D) in pregnancy and birth weight and other neonatal anthropometric measures. The present study was a population-based, multiethnic cohort study of 719 pregnant women (59 % ethnic minorities) in Oslo, Norway, delivering a singleton neonate at term and with birth weight measurements. In a representative sample, anthropometric measurements were taken. Maternal 25(OH)D was measured at gestational weeks 15 and 28. Women with 25(OH)D <37 nmol/l were recommended vitamin D3 supplementation. Separate linear regression analyses were performed to model the associations between 25(OH)D and each of the outcomes: birth weight, crown-heel length, head circumference, abdominal circumference, sum of skinfolds, mid-upper arm circumference and ponderal index. In early pregnancy, 51 % of the women were vitamin D deficient (25(OH)D<50 nmol/l). In univariate analyses and in models adjusting for maternal age, parity, education, prepregnancy BMI, season, gestational age and neonate sex, maternal 25(OH)D was significantly associated with birth weight, head circumference, abdominal circumference and ponderal index (P<0·05 for all), when used as a continuous variable and categorised (consistently low, consistently high, increasing and decreasing level). However, after adjusting for ethnicity, 25(OH)D was no longer associated with any of the outcomes. Sex-specific associations for abdominal circumference and sum of skinfolds were found (P for interaction<0·05). In conclusion, in a multiethnic cohort of pregnant women with high prevalence of vitamin D deficiency, we found no independent relation between maternal vitamin D levels and any of the neonatal anthropometric measures, and the strong association between ethnicity and neonatal outcomes was not affected by maternal vitamin D status.

Topics: 25-Hydroxyvitamin D 2; Adult; Birth Weight; Body Composition; Calcifediol; Cholecalciferol; Cohort Studies; Dietary Supplements; Female; Fetal Development; Fetal Growth Retardation; Humans; Infant, Newborn; Longitudinal Studies; Male; Maternal Nutritional Physiological Phenomena; Norway; Nutritional Status; Pregnancy; Pregnancy Complications; Prevalence; Prospective Studies; Vitamin D Deficiency

Maternal vitamin D deficiency has been implicated in adverse pregnancy outcomes. However, the association between vitamin D and inflammation, particularly adipokines, remains unexplored in pregnancy.. In 102 overweight or obese pregnant women at high-risk of gestational diabetes mellitus (GDM), we investigated relationships between maternal 25-hydroxyvitamin D (25(OH)D) concentrations at 12-15 wk gestation (baseline) and serum lipids, inflammatory markers, novel adipokines (omentin-1, visfatin, high molecular weight (HMW) adiponectin), and subsequent pregnancy outcomes (GDM, preeclampsia, preterm birth [PTB]). After adjustment for maternal factors (age, BMI, parity, ethnicity, and smoking status), baseline 25(OH)D concentrations were inversely associated with total cholesterol and triglycerides, and positively associated with HMW-adiponectin. Higher baseline 25(OH)D concentrations were associated with decreased fasting and 1-h post-OGTT glucose and reduced risk of GDM at 26-28 wk, as well as with longer gestation and reduced risk of PTB upon additional adjustment for caesarean section. Adding HMW-adiponectin to the multivariable models attenuated most associations, and HMW-adiponectin was a significant predictor in the models.. Our findings suggest that lower maternal 25(OH)D concentrations in overweight/obese pregnant women at high-risk of GDM are associated with increased cardiometabolic risks during pregnancy and adverse pregnancy outcomes, and that these associations may be mediated by HMW-adiponectin.

Topics: 25-Hydroxyvitamin D 2; Adiponectin; Adult; Biomarkers; Body Mass Index; Calcifediol; Cardiovascular Diseases; Cohort Studies; Cross-Sectional Studies; Diabetes, Gestational; Female; Hospitals, Teaching; Humans; Maternal Nutritional Physiological Phenomena; Molecular Weight; Obesity; Overweight; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Pregnancy Trimester, Second; Risk; Victoria; Vitamin D Deficiency

The aim of this study was to evaluate the prevalence of vitamin D deficiency in patients with different types of bone tumors and to elucidate whether or not there are differences in prediagnostic vitamin D levels in patients with malignant compared to benign bone tumors. Prediagnostic serum 25(OH)D levels of 105 consecutive patients that presented with bone tumors and tumor-like lesions to two Orthopedic Level I University Centers in Germany between 2011 and 2016 were measured on admission. We found an alarming and widespread rate of vitamin D deficiency in patients with bone tumors. Specifically, 83% of all patients had low vitamin D levels with a mean 25(OH)D level of 19.82 ng/ml. Notably, patients diagnosed with malignant bone tumors had significantly lower vitamin D levels compared to patients with benign bone lesions (p = 0.0008). In conclusion, it is essential to assess vitamin D levels in patients with tumors involving bone. In addition, there might be an association between vitamin D deficiency and the onset or course of primary malignant bone tumors.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Bone Neoplasms; Female; Humans; Male; Middle Aged; Prevalence; Prognosis; Risk Factors; Vitamin D Deficiency; Young Adult

To assess the prevalence of vitamin D insufficiency and deficiency and its association with cardiometabolic risk factors, controlled by adiposity, in a representative sample of prepubescent children.. Cross-sectional population-based study. Body composition was evaluated by dual-energy X-ray absorptiometry. Anthropometric measures and blood pressure were performed. Laboratory analyses were performed to determine the levels of vitamin D (25-hydroxyitamin D; 25(OH)D), glucose, insulin, serum lipids and intact parathyroid hormone. Dietary intake was assessed by three 24 h recalls.. Viçosa, Minas Gerais, Brazil, 2015.. Representative sample of 378 children aged 8 and 9 years from urban schools.. Inadequate serum concentrations of 25(OH)D were diagnosed in more than half of the children and none of them met the recommended vitamin D intake. After adjusting for confounding factors in the multiple regression analysis, lower prevalence of insulin resistance and hypertriacylglycerolaemia was found in children with serum 25(OH)D levels ≥75 nmol/l (prevalence ratio=0·25; 95 % CI 0·08, 0·85) and ≥50 nmol/l (prevalence ratio=0·61; 95 % CI 0·37, 0·99), respectively. However, after adjusting for different indicators of adiposity, insulin resistance remained independently associated and the association with hypertriacylglycerolaemia was lost after adjusting for central adiposity. The prevalence of vitamin D insufficiency/deficiency was associated with the number of cardiometabolic alterations in children.. The study results showed that prevalence of vitamin D insufficiency/deficiency was high among the children and insulin resistance was the main cardiometabolic alteration associated with this condition, even in a tropical climate country such as Brazil.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Biomarkers; Brazil; Calcifediol; Cardiovascular Diseases; Child; Child Nutritional Physiological Phenomena; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Humans; Insulin Resistance; Male; Nutritional Status; Poisson Distribution; Prevalence; Risk Factors; Severity of Illness Index; Urban Health; Vitamin D Deficiency

In 2010, the dietary guidelines for vitamin D for Canadians and Americans aged 1-70 years were revised upward. It is unknown whether the vitamin D status of Canadian children improved after 2010. We compared the prevalence of vitamin D sufficiency (25-hydroxy vitamin D (25(OH)D) concentration of ≥50 nmol/L), 25(OH)D concentration and the frequency of consuming vitamin D-rich foods among children aged 6-18 years-old using data from the nationally representative 2007/2009 and 2012/2013 Canadian Health Measures Surveys. Associations of sociodemographic, anthropometric, seasonal, and regional variables with achieving vitamin D sufficiency, 25(OH)D concentration, and consumption of vitamin D-rich foods were assessed using multiple logistic and linear regression models. 79% and 68% of children in 2007/2009 and 2012/2013 respectively, were vitamin D sufficient. The main dietary source of vitamin D was milk. Between 2007/2009 and 2012/2013, the frequency of milk and fish consumption declined, but egg and red meat consumption was unchanged. Age, income, weight status, season and ethnicity were associated with 25(OH)D concentration and vitamin D sufficiency. Vitamin D status declined after the upward revision of dietary guidelines for vitamin D, consequently, dietary intake was inadequate to meet sufficiency. Public health initiatives to promote vitamin D-rich foods and supplementation for Canadian children are needed.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adolescent Nutritional Physiological Phenomena; Animals; Biomarkers; Canada; Child; Child Nutritional Physiological Phenomena; Diet, Healthy; Female; Food, Fortified; Health Plan Implementation; Humans; Male; Milk; Nutrition Policy; Nutrition Surveys; Nutritional Status; Patient Compliance; Prevalence; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency/insufficiency is currently considered to be a re-emerging public health problem globally. This study was designed to determine the prevalence of vitamin D deficiency and insufficiency and to investigate its trend from 2001 to 2013 in a longitudinal study of Iranian adults. This study was part of a population-based, longitudinal ongoing study of Iranian healthy adults aged 35 y and older at baseline. Serum vitamin D level was assessed in a sub-sample of 370 subjects, who were apparently healthy at the time of recruitment in 2001 and were free from MetS, in three phases (2001, 2007 and 2013) during the 12-y study period. Adjusted prevalence and trend of vitamin D deficiency were calculated. Mean serum vitamin D levels increased over the time of the study (52.12, 54.27 and 62.28 nmol/L, respectively) and the prevalence of vitamin D deficiency decreased (30.5, 27.0 and 24.4, respectively). However, the prevalence of vitamin D insufficiency did not change over this time period. The risk of vitamin D deficiency decreased significantly in 2007 [OR: 0.73 (95% CI: 0.53, 0.99)] and 2013 [OR: 0.50 (95% CI: 0.36, 0.70)] compared to the baseline. The present study demonstrated some improvement in serum vitamin D levels, while the prevalence of vitamin D inadequacy was still high. Considering the possible health consequences of vitamin D deficiency, there is an urgent need for developing population-wide strategies, such as supplementation and fortification, to prevent or control vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Asymptomatic Diseases; Calcifediol; Cohort Studies; Diet; Female; Health Transition; Humans; Iran; Longitudinal Studies; Male; Middle Aged; Nutrition Surveys; Nutritional Status; Prevalence; Risk Factors; Vitamin D Deficiency

Ongoing studies in the Middle East, particularly in the Arabian Gulf countries, have reported extremely low levels of serum vitamin D across age and gender. In Kuwait, vitamin D deficiency is prevalent in adolescent girls and in adult women. A number of risk factors have been reported, among which gender, age, and obesity are a few. Because adequate vitamin D status is necessary to promote bone mineral accrual in childhood, and because low vitamin D levels have been associated with a wide range of health problems, there is concern that growing children with low vitamin D may be at higher risk for developing diseases. The aim of this study was to assess vitamin D levels in elementary schoolchildren.. Kuwaiti schoolchildren were recruited and assessed for their serum vitamin D, 25(OH)D, parathyroid hormone (PTH) and adjusted serum calcium (adj-Ca). Anthropometric measurements and data on lifestyle and health status were recorded during an interview.. In a total of 199 schoolchildren, median (IQR) age was 8.5 (7.0-9.5 years), 25(OH)D was 30 (22-39 nmol/L), PTH was 4.7 (3.8-5.9 pmol/L), and adj-Ca was 2.39 (2.33-2.44 mmol/L). Boys had higher levels of 25(OH)D (18.3% vs 6.6% had levels ≥50 nmol/L) and lower levels of PTH (94.6% vs 80.2% had levels <7 pmol/L) than girls. Significant risk factors for 25(OH)D levels <25 nmol/L included being ≤8.5 years old (OR 4.95, 95% CI: 1.92-12.74), having PTH ≥7 pmol/L (OR 2.28, 95% CI: 1.17-4.46), being female (OR 2.44, 95% CI: 1.22-4.88), and being overweight or obese (OR 2.18, 95% CI: 1.11-4.26).. The results show relatively low levels of 25(OH)D in young schoolchildren in Kuwait, with lower levels in girls. Given the association of 25(OH)D with a wide range of ailments, it is necessary to further examine the causes and risk factors of low vitamin D in this age group to prevent associated health problems.

Topics: 25-Hydroxyvitamin D 2; Age Factors; Calcium; Child; Cross-Sectional Studies; Female; Humans; Kuwait; Male; Obesity; Parathyroid Hormone; Risk Factors; Sex Factors; Vitamin D; Vitamin D Deficiency

To quantify muscle strength and size in subjects with impaired glucose tolerance (IGT) in relation to intramuscular non-contractile tissue, the severity of neuropathy and vitamin D level.. A total of 20 subjects with impaired glucose tolerance and 20 control subjects underwent assessment of strength and size of knee extensor, flexor and ankle plantar and dorsi-flexor muscles, as well as quantification of intramuscular non-contractile tissue and detailed assessment of neuropathy and serum 25-hydroxy vitamin D levels.. In subjects with impaired glucose tolerance, proximal knee extensor strength (P = 0.17) and volume (P = 0.77), and knee flexor volume (P = 0.97) did not differ from those in control subjects. Ankle plantar flexor strength was significantly lower (P = 0.04) in the subjects with impaired glucose tolerance, with no difference in ankle plantar flexor (P = 0.62) or dorsiflexor volume (P = 0.06) between groups. Intramuscular non-contractile tissue level was significantly higher in the ankle plantar flexors and dorsiflexors (P = 0.03) of subjects with impaired glucose tolerance compared with control subjects, and it correlated with the severity of neuropathy. Ankle plantar flexor muscle strength correlated significantly with corneal nerve fibre density (r = 0.53; P = 0.01), a sensitive measure of small fibre neuropathy, and was significantly lower in subjects with vitamin D deficiency (P = 0.02).. People with impaired glucose tolerance have a significant reduction in distal but not proximal leg muscle strength, which is not associated with muscle atrophy, but with increased distal intramuscular non-contractile tissue, small fibre neuropathy and vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Aged; Ankle; Calcifediol; Early Diagnosis; Female; Glucose Intolerance; Humans; Knee; Leg; Lipid Metabolism; Magnetic Resonance Imaging; Male; Middle Aged; Muscle Strength; Muscle Weakness; Muscle, Skeletal; Polyneuropathies; Severity of Illness Index; Small Fiber Neuropathy; Vitamin D Deficiency

The present study investigated the associations between serum vitamin D levels and carotid intima-media thickness (CIMT), carotid plaque and atherosclerosis in 71 Korean adults. CIMT and the presence of carotid plaque were assessed with a high-resolution B-mode ultrasound system, and carotid atherosclerosis was defined as a mean CIMT value >0.9 mm or the presence of carotid plaque. A vitamin D deficiency was associated with the presence of carotid plaque (adjusted odds ratio [aOR]: 9.25, 95% confidence interval [CI]: 1.52-56.3; p = 0.016). As serum vitamin D levels increased, the presence of high-risk carotid plaque decreased (aOR: 0.84, 95%CI: 0.72-0.99; p = 0.039). Serum vitamin D levels was negatively associated with carotid atherosclerosis (aOR: 0.86, 95%CI: 0.76-0.97; p = 0.018). Further studies are needed to investigate whether vitamin D supplementation would be effective for the prevention of atherosclerosis and cardiovascular diseases.

Topics: 25-Hydroxyvitamin D 2; Atherosclerosis; Biomarkers; Calcifediol; Carotid Intima-Media Thickness; Carotid Stenosis; Cross-Sectional Studies; Female; Humans; Logistic Models; Male; Mass Screening; Middle Aged; Nutritional Status; Prevalence; Republic of Korea; Risk Factors; Self Report; Severity of Illness Index; Vitamin D Deficiency

This study assessed the association between gender difference with metabolic syndrome (MetS), metabolic syndrome score (MSS) and serum vitamin D levels in Korean adults. Analyses were restricted to 5147 adults (2162 men; 2985 women) aged 20 and older, using the 2012 Korean National Health and Nutrition Examination Survey (KNHANES) data. In the non-adjusted model, serum 25-hydroxyvitamin D [25(OH)D] levels were inversely associated with MetS (p = .001) and MSS (p = .009) in men, but positively associated with MetS (p = .002) and MSS (p < .001) in women. However, when adjusted for related variables (including age), serum 25(OH)D levels were inversely associated with MetS (p < .001) and MSS (p < .001) in men, but were not associated with MetS (p = .200) and MSS (p = .541) in women. In conclusion, increases in MetS and its components were inversely associated with the serum vitamin D concentration in men.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Biomarkers; Calcifediol; Cross-Sectional Studies; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Nutrition Surveys; Nutritional Status; Odds Ratio; Prevalence; Republic of Korea; Risk Factors; Severity of Illness Index; Sex Factors; Vitamin D Deficiency; Young Adult

The association of vitamin D status with high body adiposity is poorly investigated in the chronic kidney disease (CKD) population. The aim of the present study was to describe vitamin D status and to identify body adiposity predictors of vitamin D deficiency, in a nondialyzed CKD population inhabiting a tropical city.. This cross-sectional study included patients with CKD, defined as estimated glomerular filtration rate (eGFR) <60 mL/min, regularly treated by an interdisciplinary team in an outpatient university clinic, set in a Brazilian city (latitude: 22°54'S; 43°12'W). Adiposity parameters analyzed were body mass index (BMI), total body adiposity (dual-energy x-ray absorptiometry [DXA] and body adiposity index [BAI]), and central body adiposity (DXA-trunk fat and waist-to-height ratio [WHtR]). Laboratory parameters included serum concentrations of 25-hydroxyvitamin D, phosphate, parathyroid hormone, and insulin (insulin resistance [IR evaluation: homeostasis model assessment; HOMA]).. Just under half of the CKD population presented sufficient concentration of 25-hydroxyvitamin D. Total body adiposity, independent of age and eGFR, regardless if evaluated by DXA or BAI, was the predictor of vitamin D deficiency, which in turn was associated with higher serum phosphorus and hyperparathyroidism, but not with IR.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Aged; Body Mass Index; Brazil; Calcifediol; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Models, Biological; Nutritional Status; Obesity; Overweight; Prevalence; Renal Insufficiency, Chronic; Risk Factors; Severity of Illness Index; Tropical Climate; Vitamin D Deficiency; Waist-Height Ratio

To investigate the possible association between vitamin D deficiency and cardiovascular autonomic neuropathy in people with diabetes.. A total of 113 people with Type 1 or Type 2 diabetes [mean (interquartile range) diabetes duration 22.0 (12-31) years, mean (sd) age 56.2 (13.0) years, 58% men] underwent vitamin D (D2 and D3) assessment, and were screened for cardiovascular autonomic neuropathy using three cardiovascular reflex tests [heart rate response to deep breathing (E/I ratio), to standing (30/15 ratio) and to the Valsalva manoeuvre] and assessment of 5-min resting heart rate and heart rate variability indices.. We found an inverse U-shaped association between serum vitamin D level and E/I ratio, 30/15 ratio and three heart rate variability indices (P < 0.05). Vitamin D level was non-linearly associated with cardiovascular autonomic neuropathy diagnosis (P < 0.05 adjusted for age and sex). Linear regression models showed that an increase in vitamin D level from 25 to 50 nmol/l was associated with an increase of 3.9% (95% CI 0.1;7.9) in E/I ratio and 4.8% (95% CI 4.7;9.3) in 30/15 ratio. Conversely, an increase from 125 to 150 nmol/l in vitamin D level was associated with a decrease of 2.6% (95% CI -5.8;0.1) and 4.1% (95% CI -5.8;-0.5) in the respective outcome measures.. High and low vitamin D levels were associated with cardiovascular autonomic neuropathy in people with diabetes. Future studies should explore this association and the efficacy of treating dysvitaminosis D to prevent cardiovascular autonomic neuropathy.

Topics: 25-Hydroxyvitamin D 2; Aged; Autonomic Nervous System Diseases; Biomarkers; Calcifediol; Cardiovascular Diseases; Cohort Studies; Denmark; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Cardiomyopathies; Diabetic Neuropathies; Dietary Supplements; Female; Humans; Male; Middle Aged; Prevalence; Severity of Illness Index; Vitamin D; Vitamin D Deficiency

Carotid intima media thickness (IMT), a predictor of cardiovascular events, is reported to be higher in African-American (AA) vs White (AW) individuals. We investigated whether racial differences in IMT in obese adolescents could be explained by differences in 25 hydroxy-vitamin D [25(OH)D].. A total of 63 obese adolescents had 25(OH)D levels, determination of IMT, body composition, insulin sensitivity (IS) by hyperinsulinemic-euglycemic clamp, lipids and blood pressure (BP).. IMT was higher and 25(OH)D lower in AA vs AW. IMT correlated with 25(OH)D level (r = -0.38, P = .002) but not with IS. In multiple regression analysis, race, HbA1c, BP and age, and not 25(OH)D, BMI or IS, were the significant determinants of IMT (R. Obese AA adolescents vs AW, have higher IMT, explained by race, BP, and HbA1c. Although 25(OH)D levels contribute to the variance in IMT, the observed racial difference in IMT could be mediated through other unknown race-related factors besides 25(OH)D.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Atherosclerosis; Black or African American; Body Mass Index; Calcifediol; Carotid Intima-Media Thickness; Cross-Sectional Studies; Female; Glycated Hemoglobin; Health Status Disparities; Humans; Insulin Resistance; Male; Pediatric Obesity; Prediabetic State; Prehypertension; Risk; Seasons; Texas; Vitamin D Deficiency; White People

Fractures of bones, especially forearm fractures, are very common in children and their number is increasing. This study was designed to determine the impact of vitamin D serum levels and vitamin D receptor (VDR) polymorphisms on the occurrence of low-energy fractures in children.. The study group consisted of 100 children with clinically relevant bone fractures and a control group consisted of 127 children without fractures. Total vitamin D [25(OH)D3 plus 25(OH)D2] serum concentrations were evaluated in every patient. Genotypes for 4 restriction fragment length polymorphisms of the vitamin D receptor gene (FokI, ApaI, TaqI, and BsmI) were determined by standard polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques.. Differences in concentrations of vitamin D were observed between the group with bone fractures (median = 12 ng/ml) and the control group (median = 16 ng/ml; p = 0.000044). Higher levels of vitamin D reduced the risk of fracture by 1.06 times (p = 0.0005). No impact of particular VDR polymorphism on the occurrence of low-energy fractures in children was detected. However, there were significant differences in the prevalence of FokI polymorphism genotypes between the fracture and control groups (p = 0.05). Furthermore, the recessive "aa" genotype of ApaI polymorphism and the dominant "TT" genotype of TaqI polymorphism were associated with higher levels of vitamin D (p = 0.005 and p = 0.036, respectively).. Vitamin D deficiency is an independent risk factor for fractures in children. ApaI polymorphism recessive "aa" and TaqI polymorphism dominant "TT" genotypes are associated with higher levels of vitamin D in serum.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Child; Child, Preschool; Female; Fractures, Bone; Genotype; Humans; Male; Polymorphism, Genetic; Polymorphism, Restriction Fragment Length; Receptors, Calcitriol; Risk Factors; Vitamin D Deficiency

This study aimed to discover genetic variants in the entire 101 kB vitamin D receptor (VDR) gene for vitamin D deficiency in a group of postmenopausal Filipino women using targeted next generation sequencing (TNGS) approach in a case-control study design. A total of 50 women with and without osteoporotic fracture seen at the Philippine Orthopedic Center were included. Blood samples were collected for determination of serum vitamin D, calcium, phosphorus, glucose, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase and as primary source for targeted VDR gene sequencing using the Ion Torrent Personal Genome Machine. The variant calling was based on the GATK best practice workflow and annotated using Annovar tool. A total of 1496 unique variants in the whole 101-kb VDR gene were identified. Novel sequence variations not registered in the dbSNP database were found among cases and controls at a rate of 23.1% and 16.6% of total discovered variants, respectively. One disease-associated enhancer showed statistically significant association to low serum 25-hydroxy vitamin D levels (Pearson chi-square P-value=0.009). The transcription factor binding site prediction program PROMO predicted the disruption of three transcription factor binding sites in this enhancer region. These findings show the power of TNGS in identifying sequence variations in a very large gene and the surprising results obtained in this study greatly expand the catalog of known VDR sequence variants that may represent an important clue in the emergence of vitamin D deficiency. Such information will also provide the additional guidance necessary toward a personalized nutritional advice to reach sufficient vitamin D status.

Topics: 25-Hydroxyvitamin D 2; Aged; Aging; Calcifediol; Case-Control Studies; Computational Biology; Female; Genetic Association Studies; Genetic Predisposition to Disease; High-Throughput Nucleotide Sequencing; Humans; Incidence; Middle Aged; Osteoporosis, Postmenopausal; Osteoporotic Fractures; Philippines; Pilot Projects; Polymorphism, Single Nucleotide; Receptors, Calcitriol; Risk Factors; Vitamin D Deficiency; Vitamin D Response Element

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Dietary Supplements; Food, Fortified; Humans; Nutritional Status; Precision Medicine; Risk; Vitamin D; Vitamin D Deficiency

Low plasma 25-hydroxy-vitamin D (25OHD) and high levels of parathyroid hormone (PTH) are associated with obesity and could play a role in the occurrence of complications such as insulin resistance. The objective of the study was to evaluate whether the relationship between 25OHD status and phosphocalcic parameters differs between metabolically healthy obese (MHO) and insulin-resistant obese (IRO). This cross-sectional study included 158 consecutive adults (121 females) with obesity (body mass index (BMI) 35.15 ± 2.8 kg/m

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Biomarkers; Body Mass Index; Calcifediol; Cohort Studies; Comorbidity; Cross-Sectional Studies; Female; France; Humans; Insulin Resistance; Male; Middle Aged; Nutritional Status; Obesity; Obesity, Metabolically Benign; Parathyroid Hormone; Prediabetic State; Prevalence; Vitamin D Deficiency

The relationship between 25 hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and metabolic traits appear to differ among ethnicities and may be influenced by obesity. The aim of the study was to examine the association of serum 25(OH)D or PTH with metabolic syndrome (MetS) while controlling for adiposity in black women. Using a cross-sectional study design, 209 urban black women aged ≥ 43 years from the North West Province, South Africa, were included. Multiple regression models were used to explore the relationship between 25(OH)D or PTH and body composition. To explore the association between 25(OH)D or PTH and MetS, a separate variable was created including at least 3 of the MetS criteria, but excluding elevated waist circumference as a diagnostic criterion in a logistic regression model. The majority of the women (69.9%) were overweight or obese and 65.5% of the women had excessive adiposity using the age-specific cut-off points for body fat percentage. All body composition variables were positively associated with PTH, whereas body mass index and waist circumference, but not body fat percentage, had negative associations with 25(OH)D also after adjusting for confounders. Before and after adjusting for age, body fat, habitual physical activity, tobacco use, season of data collection, and estimated glomerular filtration rate, neither 25(OH)D nor PTH showed significant associations with MetS. Although PTH was positively associated and 25(OH)D was negatively associated with adiposity in black women, there was no association between either 25(OH)D or PTH and MetS in this study population, nor did adiposity influence these relationships.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Black People; Body Mass Index; Calcifediol; Confounding Factors, Epidemiologic; Cross-Sectional Studies; Female; Follow-Up Studies; Humans; Hyperparathyroidism; Insulin Resistance; Metabolic Syndrome; Middle Aged; Obesity; Overweight; Parathyroid Hormone; Prevalence; Prospective Studies; Risk; South America; Urban Health; Vitamin D Deficiency

An efficient and robust method to measure vitamin D (25-hydroxy vitamin D3 (25(OH)D3) and 25-hydroxy vitamin D2 in dried blood spots (DBS) has been developed and applied in the pan-European multi-centre, internet-based, personalised nutrition intervention study Food4Me. The method includes calibration with blood containing endogenous 25(OH)D3, spotted as DBS and corrected for haematocrit content. The methodology was validated following international standards. The performance characteristics did not reach those of the current gold standard liquid chromatography-MS/MS in plasma for all parameters, but were found to be very suitable for status-level determination under field conditions. DBS sample quality was very high, and 3778 measurements of 25(OH)D3 were obtained from 1465 participants. The study centre and the season within the study centre were very good predictors of 25(OH)D3 levels (P<0·001 for each case). Seasonal effects were modelled by fitting a sine function with a minimum 25(OH)D3 level on 20 January and a maximum on 21 July. The seasonal amplitude varied from centre to centre. The largest difference between winter and summer levels was found in Germany and the smallest in Poland. The model was cross-validated to determine the consistency of the predictions and the performance of the DBS method. The Pearson's correlation between the measured values and the predicted values was r 0·65, and the sd of their differences was 21·2 nmol/l. This includes the analytical variation and the biological variation within subjects. Overall, DBS obtained by unsupervised sampling of the participants at home was a viable methodology for obtaining vitamin D status information in a large nutritional study.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Calcifediol; Calibration; Desiccation; Diet Therapy; Female; Humans; Male; Middle Aged; Nutrition Assessment; Nutritional Status; Paper; Reagent Kits, Diagnostic; Reference Values; Remote Consultation; Reproducibility of Results; Seasons; Sensitivity and Specificity; Vitamin D Deficiency

To evaluate if dietary vitamin D intake is adequate for sufficient vitamin D status during early winter in children living in Sweden, irrespective of latitude or skin color.. As part of a prospective, comparative, 2-center intervention study in northern (63°N) and southern (55°N) Sweden, dietary intake, serum 25-hydroxyvitamin D (S-25(OH) D), associated laboratory variables, and sociodemographic data were studied in 5 to 7-year-old children with fair and dark skin in November and December.. Two hundred six children with fair/dark skin were included, 44/41 and 64/57 children in northern and southern Sweden, respectively. Dietary vitamin D intake was higher in northern than southern Sweden (P = 0.001), irrespective of skin color, partly due to higher consumption of fortified foods, but only met 50-70% of national recommendations (10 μg/day). S-25(OH) D was higher in northern than southern Sweden, in children with fair (67 vs 59 nmol/L; P < 0.05) and dark skin (56 vs 42 nmol/L; P < 0.001). S-25(OH) D was lower in dark- than fair-skinned children at both sites (P < 0.01), and below 50 nmol/L in 40 and 75% of dark-skinned children in northern and southern Sweden, respectively.. Insufficient vitamin D status was common during early winter in children living in Sweden, particularly in those with dark skin. Although, higher dietary vitamin D intake in northern than southern Sweden attenuated the effects of latitude, a northern country of living combined with darker skin and vitamin D intake below recommendations are important risk factors for vitamin D insufficiency.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child; Child Nutritional Physiological Phenomena; Child, Preschool; Diet; Diet, Healthy; Dietary Supplements; Humans; Longitudinal Studies; Nutritional Status; Patient Compliance; Prospective Studies; Risk Factors; Seasons; Skin; Skin Pigmentation; Socioeconomic Factors; Sunlight; Sweden; Vitamin D; Vitamin D Deficiency

A negative association between serum 25-hydroxyvitamn D (25[OH]D) concentrations and adiposity has been found in adults. We hypothesized that serum 25(OH)D concentrations of children would correlate positively with vitamin D intake and correlate negatively with adiposity measures. Using a nationally representative sample of children aged 6 to 18 years from the National Health and Nutrition Examination Survey 2005-2006 (n = 2492), serum 25(OH)D concentrations were compared with measures of adiposity (weight, waist circumference [WC], WC-to-height ratio, body mass index, skinfold thickness, and percent body fat). Based on Endocrine Society's serum 25(OH)D concentration criteria, 26.9% ± 2.3% of the children were vitamin D deficient (<20 ng/mL) and 26.5% ± 2.6% had sufficient levels (≥30 ng/mL). Controlling for age, sex, ethnicity, and income, linear regression analysis indicated that dietary vitamin D intake was positively associated with serum 25(OH)D levels (P < .05) and markers of adiposity were negatively associated with serum 25(OH)D levels: WC, WC-to-height ratio, body mass index, and triceps skinfold thickness (P < .05). A subgroup analysis (n = 2086; 8-18 years) of body fat, fat mass index, and percent body fat measured by dual-energy x-ray absorptiometry also was negatively associated with serum 25(OH)D levels (P < .05). When standardized β coefficients were compared, strength of the inverse relationship to serum 25(OH)D concentrations was very similar for several adiposity measures. In conclusion, risk of a vitamin D deficiency was fairly common among children based on Endocrine Society criteria and low serum 25(OH)D concentrations were strongly associated with increased adiposity in children.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adolescent; Adolescent Nutritional Physiological Phenomena; Biomarkers; Body Mass Index; Calcifediol; Child; Child Nutritional Physiological Phenomena; Cross-Sectional Studies; Diet; Female; Humans; Male; Nutrition Surveys; Nutritional Status; Overweight; Pediatric Obesity; Prevalence; Risk; United States; Vitamin D Deficiency

A higher incidence of osteopenia is observed among children with inherited metabolic disorders (inborn errors of metabolism, or IEMs) who consume medical food-based diets that restrict natural vitamin D-containing food sources. We evaluated the vitamin D status of children with IEMs who live in the Pacific Northwest with limited sun exposure and determined whether bone mineral density (BMD) in children with phenylketonuria (PKU), the most common IEM, correlated with diet or biochemical markers of bone metabolism. We hypothesized that children with IEMs would have lower serum vitamin D concentrations than controls and that some children with PKU would have reduced bone mineralization. A retrospective record review of 88 patients with IEMs, and 445 children on unrestricted diets (controls) found the 25-hydroxyvitamin D concentrations were normal and not significantly different between groups (IEM patients, 27.1 ± 10.9; controls, 27.6 ± 11.2). Normal BMD at the hip or spine (-2

Topics: 25-Hydroxyvitamin D 2; Academic Medical Centers; Adolescent; Adult; Biomarkers; Bone Density; Bone Diseases, Developmental; Calcifediol; Child; Cohort Studies; Cross-Sectional Studies; Electronic Health Records; Food, Formulated; Humans; Incidence; Metabolism, Inborn Errors; Oregon; Phenylketonurias; Retrospective Studies; Risk; Vitamin D Deficiency; Young Adult

We aimed to investigate the association between serum 25-hydroxyvitamin D (25[OH]D) and microvascular complications in type 2 diabetes mellitus (T2DM) patients. It was hypothesized that lower 25(OH)D would be associated with increased microvascular complications in T2DM. A total of 257 T2DM patients (111 men, 146 women) who underwent diabetic microvascular complication (peripheral neuropathy, nephropathy, retinopathy) studies were recruited. Patients were categorized into 3 groups according to vitamin D status: vitamin D sufficient (n = 41, 25[OH]D ≥ 20 ng/mL), vitamin D insufficient (n = 132, 10 ≤ 25[OH]D < 20 ng/mL), and vitamin D deficient (n = 84, 25[OH]D < 10 ng/mL). In men, the prevalence of diabetic peripheral neuropathy (DPN) was significantly higher in patients with vitamin D deficiency than in those with insufficiency or sufficiency (38%, 11.7%, and 10%, respectively; P = .005). In addition, the prevalence of diabetic nephropathy (DN) was significantly higher in women with vitamin D deficiency than in the other 2 groups (40%, 20.6%, and 0%; P = .007). Compared with men in the vitamin D-sufficient group (reference), men in the vitamin D-deficient group had an increased risk of DPN after adjusting for confounding factors (odds ratio, 7.79; 95% confidence interval, 1.52-40.05). For women, when the vitamin D-sufficient group was used as a reference, those in the vitamin D-deficient group had an increased risk of DN after adjusting for confounding factors (odds ratio, 4.27; 95% confidence interval, 1.58-11.56). This present study found that a serum 25(OH)D level less than 10 ng/mL is independently associated with increased DPN in male patients and increased DN in female patients with T2DM.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Female; Hospitals, University; Humans; Incidence; Male; Middle Aged; Nutritional Status; Outpatient Clinics, Hospital; Prevalence; Republic of Korea; Risk Factors; Severity of Illness Index; Sex Factors; Vitamin D Deficiency

We studied vitamin D intake, serum 25-hydroxyvitamin D (S-25(OH)D) concentration, determinants of S-25(OH)D and risk factors for S-25(OH)D <50 nmol/l in a population sample of Finnish children. We studied 184 girls and 190 boys aged 6-8 years, analysed S-25(OH)D by chemiluminescence immunoassay and assessed diet quality using 4-d food records and other lifestyle factors by questionnaires. We analysed the determinants of S-25(OH)D using linear regression and risk factors for S-25(OH)D <50 nmol/l using logistic regression. Mean dietary intake of vitamin D was 5·9 (sd 2·1) µg/d. Altogether, 40·8 % of children used no vitamin D supplements. Of all children, 82·4 % did not meet the recommended total vitamin D intake of 10 µg/d. Milk fortified with vitamin D was the main dietary source of vitamin D, providing 48·7 % of daily intake. S-25(OH)D was <50 nmol/l in 19·5 % of children. Consumption of milk products was the main determinant of S-25(OH)D in all children (standardised regression coefficient β=0·262; P<0·001), girls (β=0·214; P=0·009) and boys (β=0·257; P=0·003) in multivariable models. Vitamin D intake from supplements (β=0·171; P=0·035) and age (β=-0·198; P=0·015) were associated with S-25(OH)D in girls. Children who drank ≥450 g/d of milk, spent ≥2·2 h/d in physical activity, had ≥13·1 h/d of daylight time or were examined in autumn had reduced risk for S-25(OH)D <50 nmol/l. Insufficient vitamin D intake was common among Finnish children, one-fifth of whom had S-25(OH)D <50 nmol/l. More attention should be paid to the sufficient intake of vitamin D from food and supplements, especially among children who do not use fortified milk products.

Topics: 25-Hydroxyvitamin D 2; Animals; Calcifediol; Child; Child Nutritional Physiological Phenomena; Dairy Products; Diet; Diet Records; Dietary Supplements; Female; Finland; Food, Fortified; Humans; Life Style; Male; Milk; Motor Activity; Nutrition Surveys; Risk Factors; Seasons; Vitamin D; Vitamin D Deficiency

Serum vitamin D (25-hydroxyvitamin D (25OHD)) may influence serum parathyroid hormone (PTH) levels and bone mineral density (BMD). In the present study, we assessed serum 25OHD concentration and its association with PTH and BMD in urban males from Guiyang (N26.57°), the capital city of Guizhou province, Southwest China. We recruited 634 males aged >20 years from the Guiyang Health Measures Survey, and stratified them into three groups according to age: young (20-39 years), middle aged (40-59 years) and older (60-79 years). We measured serum concentrations of 25OHD, PTH levels and BMD of the lumbar spine (L1-L4), femoral neck and total hip. In addition, we also explored the relationship between 25OHD and lifestyle, socio-economic characteristics and medical history by applying covariance analysis and locally weighted regression plots. The results showed that serum 25OHD was 75 nmol/l in 12·6 % of the subjects. Higher level of serum PTH was detected in relation to lower concentrations of serum 25OHD up to 50 nmol/l. A negative correlation between serum 25OHD and PTH concentrations was observed (r -0·207, P=0·003). Mean concentration of serum PTH increased gradually and plateaued while concentrations of serum 25OHD decreased to 50 nmol/l. Gradual increase in serum PTH was observed as 25OHD concentration was <25 nmol/l (P=0·004). BMD values at all sites were greater in the higher serum 25OHD concentration group. This study shows that low concentrations of serum 25OHD were common in males, and bone health was likely to be improved when serum 25OHD values were between 30 and 50 nmol/l.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aging; Bone Density; Calcifediol; China; Cohort Studies; Cross-Sectional Studies; Humans; Hyperparathyroidism, Secondary; Male; Middle Aged; Nutrition Surveys; Osteomalacia; Parathyroid Hormone; Risk; Seasons; Urban Health; Vitamin D Deficiency; Young Adult

To determine the serum 25-hydroxycalciferol levels [25(OH)D] in adults with pre-diabetes and normoglycaemia to examine a possible association of vitamin D deficiency with pre-diabetes.. Case control study.. Armed Forces Institute of Pathology, Rawalpindi, from November 2012 to July 2013.. Atotal of 272 adults including 136 pre-diabetics and 136 normoglycaemics of either gender aged 20 years and above were consecutively inducted. Patients with diabetes mellitus, pregnancy, rickets and osteomalacia, ischemic heart disease, chronic kidney disease and chronic liver disease were excluded. Fasting Plasma Glucose (FPG) was estimated with hexokinase method on Modular p800 Roche chemistry analyzer while serum 25(OH)D was measured on Diasorin Liaison immunoassay analyzer using the chemiluminescent technique. Mean 25(OH)D levels in pre-diabetic and normoglycaemic groups were compared using Mann-Whitney U test. Spearman's correlation coefficient 'rs' was determined between serum 25(OH)D and FPG. Odds ratio for vitamin D deficiency was also calculated.. Mean serum 25(OH)D level was low in pre-diabetics (23.2 nmol/L) as compared to normoglycaemics (29 nmol/L; p=0.001). Serum 25(OH)D level had inverse correlation with FPG (rs= -0.448, p=0.000). There was also significant association of vitamin D deficiency with pre-diabetes compared with normoglycaemia (OR: 2.21, p= 0.016; 95% CI: 1.15-4.27).. Vitamin D deficiency with pre-diabetes suggested that vitamin D may have an important role in pathogenesis of pre-diabetes.

Topics: 25-Hydroxyvitamin D 2; Adult; Blood Glucose; Case-Control Studies; Female; Humans; Male; Middle Aged; Prediabetic State; Vitamin D; Vitamin D Deficiency

The 2007-2010 NHANES provides the first US nationally representative serum 25-hydroxyvitamin D [25(OH)D] concentrations measured by standardized liquid chromatography-tandem mass spectrometry.. We describe patterns for total 25(OH)D and individual metabolites in persons aged ≥1 y stratified by race-ethnicity and grouped by demographic, intake, physiologic, and lifestyle variables.. We measured 25-hydroxycholecalciferol [25(OH)D3], 25-hydroxyergocalciferol [25(OH)D2], and C3-epimer of 25(OH)D3 [C3-epi-25(OH)D3] in serum samples (n = 15,652) from the 2007-2010 cross-sectional NHANES [total 25(OH)D = 25(OH)D3 + 25(OH)D2].. Concentrations (median, detection rate) of 25(OH)D3 (63.6 nmol/L, 100%) and C3-epi-25(OH)D3 (3.40 nmol/L, 86%) were generally detectable; 25(OH)D2 was detectable in 19% of the population. Total 25(OH)D, 25(OH)D3, and C3-epi-25(OH)D3 displayed similar demographic patterns and were strongly correlated (Spearman's r > 0.70). Concentrations of 25(OH)D2 (90th percentile) were much higher in persons aged ≥60 y (17.3 nmol/L) than in younger age groups (≤4.88 nmol/L). We noted significant race-ethnicity differences in mean total 25(OH)D [non-Hispanic blacks (NHBs), Hispanics, and non-Hispanic whites (NHWs): 46.6, 57.2, and 75.2 nmol/L, respectively] and in the prevalence of total 25(OH)D <30 nmol/L overall (24% of NHBs, 6.4% of Hispanics, and 2.3% of NHWs) as well as stratified by season (winter months: 30% of NHBs, 7.5% of Hispanics, and 3.8% of NHWs; summer months: 17% of NHBs, 4.4% of Hispanics, and 1.6% of NHWs). Persons with higher vitamin D intakes (diet, supplements, or both) and those examined during May-October had significantly higher total 25(OH)D. Significant race-ethnicity interactions in a multiple linear regression model confirmed the necessity of providing race-ethnicity-specific estimates of total 25(OH)D.. Race-ethnicity differences in the prevalence of low total 25(OH)D remained strong even after adjustment for season to account for the NHANES design imbalance between season, latitude, and race-ethnicity. The strong correlation between C3-epi-25(OH)D3 and 25(OH)D3 may be because the epimer is a metabolite of 25(OH)D3. The presence of 25(OH)D2 mainly in older persons is likely a result of high-dose prescription vitamin D2.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Age Factors; Aged; Black or African American; Calcifediol; Child; Child, Preschool; Chromatography, High Pressure Liquid; Diet; Dietary Supplements; Female; Hispanic or Latino; Humans; Infant; Male; Middle Aged; Seasons; Tandem Mass Spectrometry; United States; Vitamin D; Vitamin D Deficiency; Vitamins; White People; Young Adult

The objective of this study was to examine the cross-sectional relationship between homeostasis model assessment for insulin resistance (HOMA-IR) and serum 25-hydroxyvitamin D (25-OHD) level in Chinese children and adolescents.. Anthropometric indices, lipid metabolic profile, and serum levels of glucose, insulin and 25-OHD were determined among 278 healthy prepubertal and pubertal, normal and overweight/obese children and adolescents aged 8-18 years between March 2014 and February 2015.. HOMA-IR was significantly different across vitamin D statuses (p<0.001), even after adjusting for body mass index (BMI) (p=0.035) and waist-to-height ratio (p=0.044); the difference was not significant between the vitamin D deficient and insufficient groups (p=0.120). HOMA-IR negatively correlated with serum 25-OHD level for all subjects (R2=0.148, p<0.001). Furthermore, they negatively correlated in the normal (R2=0.160, p<0.001) and overweight/obese (R2=0.086, p<0.001) groups, respectively. The regression lines of the two groups were parallel (p=0.669) but had a significantly different intercept (p<0.001). An association between HOMA-IR and BMI and serum 25-OHD level (R2=0.654, p<0.001) was demonstrated based on the stepwise multiple linear regression analysis of age, sex, pubertal maturation, BMI, waist-to-height ratio, triglyceride, cholesterol, high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), 25-OHD and HOMA-IR.. Our findings supported that lower vitamin D status is strongly associated with worse HOMA-IR.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Body Mass Index; Calcifediol; Child; China; Cross-Sectional Studies; Female; Hospitals, University; Humans; Insulin Resistance; Linear Models; Lipids; Male; Nutritional Status; Overweight; Pediatric Obesity; Severity of Illness Index; Vitamin D Deficiency; Waist-Height Ratio

Obesity is an important risk factor for non-alcoholic fatty liver disease. Few studies have evaluated the association between vitamin D and non-alcoholic fatty liver disease in obese children. Therefore, we conducted a study to examine the relationship of vitamin D levels and hepatosteatosis in obese children.. One hundred and eleven children with obesity participated in this study. Hepatosteatosis was diagnosed and graded using ultrasonography in all patients. Study participants were divided based on the presence of hepatosteatosis into two subgroups (hepatosteatosis and non-hepatosteatosis). Serum levels of 25-hydroxyvitamin D, calcium, phosphate, alkaline phosphatase, parathormone, and lipids were measured and compared.. Hepatosteatosis existed in 52% of obese children without chronic diseases. There was no statistically significant difference in the vitamin D level between the hepatosteatosis and non-hepatosteatosis groups. Alanine aminotransferase levels and the triglycerides-to-high density lipoprotein ratio were significantly higher, and the high density lipoprotein levels were significantly lower in the hepatosteatosis group compared to the non-hepatosteatosis group.. Vitamin D deficiency is not directly related with hepatosteatosis. A high ALT level and a high triglycerides-to-HDL ratio and low HDL levels are more significant in hepatic steatosis in obese children.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Body Mass Index; Calcifediol; Child; Female; Hospitals, Teaching; Humans; Insulin Resistance; Male; Non-alcoholic Fatty Liver Disease; Nutritional Status; Outpatient Clinics, Hospital; Overweight; Pediatric Obesity; Prospective Studies; Risk Factors; Severity of Illness Index; Turkey; Vitamin D Deficiency

Vitamin D deficiency impairs fertility in animal models, but the role of vitamin D in human fertility or treatment of infertility is less clear.. We examined the association between circulating 25-hydroxyvitamin D [25(OH)D] concentrations and the outcome in women undergoing assisted reproduction technologies (ARTs).. We randomly selected 100 women undergoing infertility treatment with ART enrolled in an ongoing prospective cohort study who underwent 168 treatment cycles. Serum 25(OH)D concentrations were measured in samples collected from women between days 3 and 9 of gonadotropin treatment. Generalized linear mixed models were used to evaluate the association of 25(OH)D concentrations with ART outcomes while adjusting for potential confounders and accounting for repeated treatment cycles per woman.. Median (range) serum 25(OH)D concentrations were 86.5 (33.5-155.5) nmol/L. Ninety-one percent of participants consumed multivitamins. Serum 25(OH)D concentrations were positively related to fertilization rate. The adjusted fertilization rate for women in increasing quartiles of serum 25(OH)D were 0.62 (95% CI: 0.51, 0.72), 0.53 (95% CI: 0.43, 0.63), 0.67 (95% CI: 0.56, 0.76), and 0.73 (95% CI: 0.63, 0.80), respectively (P-trend = 0.03). This association persisted when analyses were restricted to women with serum 25(OH)D between 50 and 125 nmol/L when models were further adjusted for season of blood draw and when analyses were restricted to the first treatment cycle. However, 25(OH)D concentrations were unrelated to probability of pregnancy (P-trend = 0.83) or live birth after ART (P-trend = 0.47).. Vitamin D may be associated with higher fertilization rates, but this apparent benefit does not translate into higher probability of pregnancy or live birth. This trial was registered at www.clinicaltrials.gov as NCT00011713.

Topics: 25-Hydroxyvitamin D 2; Adult; Boston; Calcifediol; Cohort Studies; Confounding Factors, Epidemiologic; Dietary Supplements; Family Characteristics; Female; Fertilization in Vitro; Humans; Infertility, Female; Infertility, Male; Live Birth; Male; Pregnancy; Pregnancy Rate; Prospective Studies; Sperm Injections, Intracytoplasmic; Sperm-Ovum Interactions; Vitamin D Deficiency; Vitamins

Vitamin D deficiency is a global health concern that is prevalent in Ireland. The vitamin D status of elite Irish athletes following implementation of a revised supplementation policy in 2010/2011 has not been explored to date. This study aimed to assess the vitamin D status of elite Irish athletes participating in high-profile sports and establish if equatorial travel, supplementation and/or sunbed use predict vitamin D status. Across Ireland, blood samples (n = 92) were obtained from cricketers (n = 28), boxers (n = 21) and women's rugby sevens players (n = 43) between November 2013 and April 2015. Total 25-hydroxyvitamin D (25(OH)D) concentrations were quantified using LC-MS/MS. Parathyroid hormone and adjusted calcium concentrations were measured by clinical biochemistry. Athletes completed a questionnaire that queried equatorial travel, supplementation and sunbed use. Vitamin D sufficiency (25(OH)D >50 nmol/L) was evident in 86% of athletes. Insufficiency (31-49 nmol/L) and deficiency (<30 nmol/L) was present in only 12% and 2% of athletes respectively. On average, athletes from all sport disciplines were vitamin D sufficient and 25% reported vitamin D supplementation which was a significant positive predictor of vitamin D status, (OR 4.31; 95% CI 1.18-15.75; p = 0.027). Equatorial travel and sun bed use were reported in 47% and 16% of athletes respectively however these factors did not predict vitamin D status (both p > 0.05). Although different cohorts were assessed, the overall prevalence of vitamin D insufficiency/deficiency was 55% in 2010/2011 compared with only 14% in 2013/2015. Targeted supplementation is highly effective in optimising vitamin D status, negating the need for blanket-supplementation in elite cohorts.

Topics: 25-Hydroxyvitamin D 2; Athletes; Calcifediol; Cohort Studies; Dietary Supplements; Female; Humans; Ireland; Male; Nutrition Policy; Nutritional Status; Patient Compliance; Physical Exertion; Prevalence; Seasons; Self Report; Sports and Recreational Facilities; Sports Nutritional Physiological Phenomena; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency or insufficiency may play a role in the pathogenesis of certain autoimmune diseases.. To measure vitamin D levels in children with Hashimoto’s thyroiditis (HT) (either with subclinical or marked hypothyroidism) and in healthy controls.. We included 68 children with HT aged 12 ± 4 years (39 females) from a pediatric outpatient clinic and 68 healthy children aged 10 ± 4 years (37 females). Calcium metabolism parameters, thyroid function tests and anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (anti-TG) and 25 hydroxy vitamin D (25OHD) levels were measured.. Patients were older than controls but well matched by gender distribution. Mean 25OHD levels were significantly lower in HT patients than controls (16.8 ± 9.3 and 24.1 ± 9.4 ng/mL respectively, P < 0.01). Frequency of vitamin D deficiency was 76 and 35% in HT patients and controls, respectively (P < 0.001).. Vitamin D deficiency is more common in children with HT than healthy controls.

Topics: 25-Hydroxyvitamin D 2; Autoantibodies; Case-Control Studies; Child; Female; Hashimoto Disease; Humans; Iodide Peroxidase; Male; Vitamin D Deficiency

Deficiency of vitamin D is known to be effective in the development of hypertension, coronary artery disease, myocardial infarction, and stroke. Deficiency of vitamin D was also shown to be associated with new onset atrial fibrillation (AF) by activating the renin-angiotensin system. This study investigated whether or not levels of vitamin D are effective in the development of AF after coronary artery bypass grafting (CABG) surgery.. A total of 283 patients undergoing CABG were included in this study. Clinical information, history of medication use, serum 25 hydroxy(OH) vitamin D, and calcium levels of all patients were evaluated preoperatively.. AF developed postoperatively in 72 (25%) of patients. Serum 25(OH) vitamin D levels of patients in whom AF developed after CABG were significantly lower than patients in whom AF did not occur (15.6 ± 7.4 versus 19.1 ± 9.1; P = .004). Independent variables which were predictors of AF development in multivariate logistic regression analysis were ejection fraction (odds ratio [OR]: 0.93; 95% confidence interval [CI] 0.89-0.97; P = .003), left atrial dimensions (OR: 1.47; 95% CI 1.26-1.71; P < .001), and serum 25(OH) vitamin D levels (OR: 0.95; 95% CI 0.91-0.99; P = .035).. This study has shown that deficiency of vitamin D is associated with new onset AF post-CABG surgery.

Topics: 25-Hydroxyvitamin D 2; Aged; Atrial Fibrillation; Coronary Artery Bypass; Coronary Disease; Electrocardiography; Female; Follow-Up Studies; Humans; Incidence; Male; Middle Aged; Postoperative Complications; Retrospective Studies; Risk Factors; Time Factors; Turkey; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Child; Humans; Vitamin D; Vitamin D Deficiency

Vitamin D insufficiency and deficiency have been associated with an increased risk of adverse pregnancy outcomes. Controversy remains as findings have been inconsistent between disparate populations. The aim of this study was to investigate the relationship between vitamin D status and pregnancy outcomes in a large, prospective pregnancy cohort. 25-Hydroxyvitamin D concentration was analysed in serum samples collected at 15 weeks of gestation from 1710 New Zealand women participating in a large, observational study. Associations between vitamin D status and pre-eclampsia, preterm birth, small for gestational age (SGA) and gestational diabetes were investigated. The mean 25-hydroxyvitamin D concentration was 72·9 nmol/l. In all, 23 % had 25-hydroxyvitamin D concentrations 75 nmol/l (OR 2·3; 95 % CI 1·1, 5·1). However, this effect was not significant when adjustments were made for BMI and ethnicity (OR 1·8; 95 % CI 0·8, 4·2). 25-Hydroxyvitamin D concentration at 15 weeks was not associated with development of pre-eclampsia, spontaneous preterm birth or SGA infants. Pregnancy complications were low in this largely vitamin D-replete population.

Topics: 25-Hydroxyvitamin D 2; Biomarkers; Calcifediol; Cohort Studies; Diabetes, Gestational; Female; Fetal Growth Retardation; Humans; Incidence; Maternal Nutritional Physiological Phenomena; New Zealand; Nutritional Status; Pre-Eclampsia; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Pregnancy Trimester, Second; Premature Birth; Prevalence; Prospective Studies; Risk; Severity of Illness Index; Vitamin D Deficiency

Vitamin D is thought to regulate skeletal muscle function and boost physical performance. The aim of this study was to assess the relationship between vitamin D and physical performance in physically active children. This cross-sectional study included 125 children who practice football as a leisure activity. Plasma 25-hydroxyvitamin D (25-OHD) was assessed using a chemiluminescence immunoassay method. Vitamin D inadequacy was defined as 25-OHD < 20 ng/mL. Physical performance testing included measurements of muscle strength (maximal isometric contraction), jumping ability (vertical jump, standing broad jump, triple hop test), linear sprint (10 m and 20 m), and agility (9 × 4-m shuttle run). Plasma 25-OHD concentrations were positively correlated with muscle strength (r = 0.539; p < 0.001), vertical jump (r = 0.528; p < 0.001), and standing broad jump (r = 0.492; p < 0.001) but inversely correlated with sprint performance (r = -0.539; p < 0.001). In multivariate analysis models, plasma 25-OHD concentrations were associated with each physical performance parameter independently of age, maturity status, body mass index, fat mass, and protein and calcium intakes. In conclusion, a low plasma 25-OHD level was associated with decreased muscle strength, agility, and jumping and sprinting abilities in physically active children. Vitamin D inadequacy may limit exercise performance. Further research should verify whether correction of vitamin D deficiency enhances physical performance.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adolescent Behavior; Athletic Performance; Calcifediol; Child; Child Behavior; Confounding Factors, Epidemiologic; Cross-Sectional Studies; Healthy Lifestyle; Humans; Male; Motor Activity; Muscle Strength; Muscle Weakness; Physical Fitness; Prevalence; Soccer; Sports and Recreational Facilities; Track and Field; Tunisia; Vitamin D Deficiency

To determine changes over time of serum levels of 25-hydroxy vitamin D (25(OH)D) in Mexican patients with SLE and their relationship with disease activity.. Longitudinal and observational study. Women with SLE were included. Serum levels of 25(OH)D were measured at baseline and after two years; the disease activity was measured with MEX-SLEDAI. Patients with initial suboptimal levels of 25(OH)D received supplements or increased doses of calcitriol.. 105 women with SLE were included, mean age 49.4 ± 11 years. Serum levels of 25(OH)D were higher at two years (baseline 20 ± 6.8 vs. follow-up 22.7 ± 7.7; p = < 0.001). There were no differences between disease activity scores at baseline and two years (baseline 1.7 ± 1.9 vs. follow-up 1.1 ± 1.7; p = 0.7). Serum levels of 25(OH)D did not correlate with disease activity during the follow up, p = 0.7. No correlation was found between changes in MEX-SLEDAI scores and serum levels of 25(OH)D, p = 0.87.. Mexican women with SLE had increased serum levels of 25(OH)D. No correlation between serum levels of 25(OH)D and disease activity was found.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Cross-Sectional Studies; Female; Humans; Longitudinal Studies; Lupus Erythematosus, Systemic; Mexico; Middle Aged; Vitamin D Deficiency

Children with cancer are potentially at a high risk of plasma 25-hydroxyvitamin D (25(OH)D) inadequacy, and despite UK vitamin D supplementation guidelines their implementation remains inconsistent. Thus, we aimed to investigate 25(OH)D concentration and factors contributing to 25(OH)D inadequacy in paediatric cancer patients. A prospective cohort study of Scottish children aged 75 nmol/l). In all, eighty-two patients (median age 3·9, interquartile ranges (IQR) 1·9-8·8; 56 % males) and thirty-five controls (median age 6·2, IQR 4·8-9·1; 49 % males) were recruited. 25(OH)D inadequacy was highly prevalent in the controls (63 %; 22/35) and in the patients (64 %; 42/65) at both baseline and during treatment (33-50 %). Non-supplemented children had the highest prevalence of 25(OH)D inadequacy at every stage with 25(OH)D median ranging from 32·0 (IQR 21·0-46·5) to 45·0 (28·0-64·5) nmol/l. Older age at baseline (R -0·46; P<0·001), overnutrition (BMI≥85th centile) at 3 months (P=0·005; relative risk=3·1) and not being supplemented at 6 months (P=0·04; relative risk=4·3) may have contributed to lower plasma 25(OH)D. Paediatric cancer patients are not at a higher risk of 25(OH)D inadequacy than healthy children at diagnosis; however, prevalence of 25(OH)D inadequacy is still high and non-supplemented children have a higher risk. Appropriate monitoring and therapeutic supplementation should be implemented.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Age Factors; Body Mass Index; Calcifediol; Case-Control Studies; Child; Child, Preschool; Cohort Studies; Follow-Up Studies; Humans; Male; Neoplasm Staging; Neoplasms; Overnutrition; Pilot Projects; Prevalence; Prospective Studies; Risk; Scotland; Severity of Illness Index; Vitamin D Deficiency

To assess vitamin D status among Cypriot adolescents and investigate potential determinants including BMI and body fat percentage (BF%).. Participants had cross-sectional assessments of serum vitamin D, physical activity, dietary vitamin D intake and sun exposure. Linear and logistic regression models were used to explore the associations of vitamin D with potential predictors.. Hospitals, Cyprus, November 2007-May 2008.. Adolescents (n 671) aged 16-18 years.. Mean serum vitamin D was 22·90 (sd 6·41) ng/ml. Only one in ten children had sufficient levels of vitamin D (≥30 ng/ml), while the prevalence of vitamin D deficiency (12-20 ng/ml) and severe deficiency (<12 ng/ml) was 31·7 % and 4·0 %, respectively. Lower vitamin D was associated with winter and spring season, female gender, reduced sun exposure in winter and darker skin. Participants with highest BMI and BF% when compared with a middle reference group had increased adjusted odds of vitamin D insufficiency (OR = 3·00; 95 % CI 1·21, 7·45 and OR = 5·02; 95 % CI 1·80, 13·97, respectively). A similar pattern, although not as strong, was shown for vitamin D deficiency with BF% (OR = 1·81; 95 % CI 1·04, 3·16) and BMI (OR = 1·51; 95 % CI 0·85, 2·67). Participants in the lowest BMI and BF% groups also displayed compromised vitamin D status, suggesting a U-shaped association.. Vitamin D deficiency in adolescence is very prevalent in sunny Cyprus, particularly among females, those with darker skin and those with reduced sun exposure in winter. Furthermore, vitamin D status appears to have a U-shaped association with adiposity measures.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adolescent; Adolescent Nutritional Physiological Phenomena; Body Mass Index; Calcifediol; Cohort Studies; Cross-Sectional Studies; Cyprus; Female; Humans; Male; Nutrition Surveys; Nutritional Status; Overweight; Prevalence; Risk; Seasons; Severity of Illness Index; Sex Characteristics; Skin Pigmentation; Vitamin D Deficiency

The aim was to investigate autumn vitamin D intake and status in 7-year-old Icelanders, fitting BMI and cardiorespiratory fitness as predictors.. Three-day food records and fasting blood samples were collected evenly from September to November, and cardiorespiratory fitness was measured with an ergometer bike. Food and nutrient intakes were calculated, and serum 25-hydroxyvitamin D (s-25(OH)D) and serum parathyroid hormone were analysed. Suboptimal vitamin D status was defined s-25(OH)D <50 nmol/l, and deficient status as s-25(OH)D <25 nmol/l.. School-based study in Reykjavik, Iceland in 2006.. Of the 7-year-olds studied (n 265), 165 returned valid intake information (62 %), 158 gave blood samples (60 %) and 120 gave both (45 %).. Recommended vitamin D intake (10 μg/d) was reached by 22·4 % of the children and 65·2 % had s-25(OH)D <50 nmol/l. Median s-25(OH)D was higher for children taking vitamin D supplements (49·2 nmol/l v. 43·2 nmol/l, respectively; P < 0·0 0 1). Median s-25(OH)D was lower in November (36·7 nmol/l) than in September (59·9 nmol/l; P < 0·001). The regression model showed that week of autumn accounted for 18·9 % of the variance in s-25(OH)D (P < 0·001), vitamin D intake 5·2 % (P < 0·004) and cardiorespiratory fitness 4·6 % (P < 0·005).. A minority of children followed the vitamin D recommendations and 65 % had suboptimal vitamin D status during the autumn. Week of autumn was more strongly associated with vitamin D status than diet or cardiorespiratory fitness, which associated with vitamin D status to a similar extent. These results demonstrate the importance of sunlight exposure during summer to prevent suboptimal vitamin D status in young schoolchildren during autumn in northern countries. An increased effort is needed for enabling adherence to the vitamin D recommendations and increasing outdoor activities for sunlight exposure.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child; Child Nutritional Physiological Phenomena; Cohort Studies; Diet; Diet Records; Dietary Supplements; Female; Humans; Iceland; Male; Nutrition Policy; Nutritional Status; Parathyroid Hormone; Patient Compliance; Physical Fitness; Schools; Seasons; Urban Health; Vitamin D; Vitamin D Deficiency

Chronic vitamin D deficiency has been associated in some patients with diffuse musculoskeletal pain. These unspecific symptoms may partly explain why vitamin D deficiency is often diagnosed late. Our aim was to analyse health-care claims after vitamin D supplementation in patients likely to have vitamin D deficiency.. Ambulatory health-care claims were compared before and after a vitamin D supplementation prescribed following a 25-hydroxyvitamin D assay.. Health Insurance Fund (FHIF) database of the Rhône-Alpes area, France.. Among patients reimbursed for a 25-hydroxyvitamin D assay between 1 December 2008 and 31 January 2009, those supplemented with vitamin D after the assay were matched on the date of assay to patients who did not receive vitamin D.. Among the 3023 patients who had a 25-hydroxyvitamin D assay, 935 were consequently supplemented and matched to 935 patients not supplemented. Their median age was 50·0 and 49·5 years, respectively. Patients supplemented decreased their muscle relaxant consumption whereas no change was observed in the reference group, the difference between the two groups was significant (P=0·03). Second and third Pain Relief Ladder prescriptions decreased in both groups but not significantly differently between groups (P=0·58). There was a decrease in prescriptions of biological examination in both groups with no significant difference.. Besides a decrease in muscle relaxant prescriptions in the supplemented group, it was difficult to assess the impact of vitamin D supplementation in patients likely to have vitamin D deficiency. Prospective cohort studies and randomized trials are needed to assess the efficiency of screening and supplementing vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Ambulatory Care; Calcifediol; Cohort Studies; Delayed Diagnosis; Dietary Supplements; Drug Prescriptions; Female; Follow-Up Studies; France; Humans; Insurance, Health; Male; Matched-Pair Analysis; Middle Aged; Muscle Relaxants, Central; Musculoskeletal Pain; Vitamin D; Vitamin D Deficiency; Young Adult

To examine cross-sectional relationships between plasma vitamin D and cardiometabolic risk factors in young adults.. Data were collected from interviews, physical examinations and biomarker measurements. Total plasma 25-hydroxyvitamin D (25(OH)D) was measured using LC-tandem MS. Associations between 25(OH)D and cardiometabolic risk factors were modelled using weighted linear regression with robust estimates of standard errors.. Individuals born in Jerusalem during 1974-1976.. Participants of the Jerusalem Perinatal Study (n 1204) interviewed and examined at age 32 years. Participants were oversampled for low and high birth weight and for maternal pre-pregnancy obesity.. Mean total 25(OH)D concentration among participants was 21·7 (sd 8·9) ng/ml. Among males, 25(OH)D was associated with homeostatic model assessment of insulin resistance (natural log-transformed, β=-0·011, P=0·004) after adjustment for BMI. However, these associations were not present among females (P for sex interaction=0·005).. We found evidence for inverse associations of 25(OH)D with markers of insulin resistance among males, but not females, in a healthy, young adult Caucasian population. Prospective studies and studies conducted on other populations investigating sex-specific effects of vitamin D on cardiometabolic risk factors are warranted.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Body Mass Index; Calcifediol; Cardiovascular Diseases; Cohort Studies; Cross-Sectional Studies; Female; Humans; Hyperglycemia; Hyperinsulinism; Hyperlipidemias; Insulin Resistance; Israel; Longitudinal Studies; Male; Metabolic Syndrome; Overweight; Risk Factors; Sex Factors; Vitamin D Deficiency

The aim of this study is to assess the prevalence and predictors of depressive symptoms in women with polycystic ovary syndrome (PCOS). In a cross-sectional study of 114 women seeking consultation for symptoms of PCOS (menstrual irregularity, hirsutism, and/or acne), personal and family history of depression (HD and FHD respectively) were enquired. Vitamin D status (n = 104) and manifest depressive symptoms assessed by personal health questionnaire (PHQ) (MD) were evaluated in a subset (85). Relationships between HD and MD with PCOS symptoms, FHD, and vitamin D status were assessed using adjusted analyses. Thirty-five percent acknowledged a HD; MD (PHQ > 4) was apparent in 43 %. HD was associated with hirsutism (OR 2.4, 95 % CI 1.01-5.9), disturbed sleep (OR 3.0, 95 % CI 1.3-6.9), and with FHD (OR 4.8, 95 % CI 1.7-13.5). Disturbed sleep (OR 2.4, 95 % CI 1.01-5.7) and FHD (OR 3.8, 95 % CI 1.3-11.2) were independent predictors of HD adjusting for race and BMI. An inverse correlation was noted between serum 25 OH vitamin D (25OHD) levels and PHQ score, but only in those with vitamin D deficiency (25OHD ≤ 30 ng/ml, n = 57, r =-0.32, p = 0.015). 25OHD < 20 ng/ml (OR 3.5, 95 % CI 1.1-11.8) and HD (OR 12.8, 95 % CI 3.6-45.2) predicted scoring in the highest PHQ tertile after adjusting for hirsutism, BMI, and race. In women with PCOS, disturbed nocturnal sleep and FDH predicted personal HD, whereas HD and vitamin D deficiency related to the severity of MD symptoms.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Body Mass Index; Cross-Sectional Studies; Depression; Female; Hirsutism; Humans; Logistic Models; Multivariate Analysis; Polycystic Ovary Syndrome; Prevalence; Severity of Illness Index; Surveys and Questionnaires; Vitamin D; Vitamin D Deficiency

Few epidemiological studies have investigated the association between circulating concentrations of the active vitamin D metabolite 1,25(OH)2D and metabolic syndrome. We sought to determine whether blood levels of 1,25(OH)2D are associated with metabolic syndrome and its individual components, including waist circumference, triglycerides, blood pressure, and glucose, and high-density lipoprotein. We also investigated these associations for the more abundant precursor vitamin D metabolite, 25(OH)D.. Participants from two completed clinical trials of colorectal neoplasia with available metabolic syndrome data and blood samples for measurement of 1,25(OH)2D (n=1048) and 25(OH)D (n=2096) were included. Cross-sectional analyses of the association between concentrations of 1,25(OH)2D, 25(OH)D, metabolic syndrome, and its components were conducted.. A statistically significant inverse association was observed for circulating concentrations of 1,25(OH)2D and metabolic syndrome, with adjusted ORs (95% CIs) of 0.73 (0.52-1.04) and 0.52 (0.36-0.75) for the second and third tertiles of 1,25(OH)2D, respectively (p-trend <0.001). Significant inverse relationships were also observed between 1,25(OH)2D and high triglycerides (p-trend <0.001), and low high-density lipoprotein (p-trend <0.001). For 25(OH)D concentrations, significant inverse associations were found for metabolic syndrome (p-trend <0.01), high waist circumference (p-trend <0.04) and triglyceride levels (p-trend <0.01). Participants with 25(OH)D ≥30 ng/ml and in the highest tertile of 1,25(OH)2D demonstrated significantly lower odds of metabolic syndrome, with an OR (95% CI) of 0.38 (0.19-0.75) compared to those in the lowest category for both metabolites.. These results provide new evidence that the relatively rarely-studied active hormonal form of vitamin D, 1,25(OH)2D, is associated with metabolic syndrome and its components, and confirm prior findings for 25(OH)D. The finding that 1,25(OH)2D is related to high-density lipoprotein, while 25(OH)D is not, suggests that there may be an independent mechanism of action for 1,25(OH)2D in relation to metabolic dysregulation.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcitriol; Cross-Sectional Studies; Diet; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Seasons; Sex Factors; Socioeconomic Factors; Vitamin D Deficiency; Waist Circumference

Control of human tuberculosis (TB) requires induction and maintenance of both macrophage and T cell effector functions. We demonstrate that pulmonary TB patients with a vitamin D deficiency had significantly reduced local levels of the vitamin D-inducible antimicrobial peptide LL-37 in granulomatous lesions compared to distal parenchyma from the infected lung. Instead, TB lesions were abundant in CD3(+) T cells and FoxP3(+) regulatory T cells as well as IgG-secreting CD20(+) B cells, particularly in sputum-smear positive patients with cavitary TB. Mycobacteria-specific serum IgG titers were also elevated in patients with active TB. An up-regulation of the B cell stimulatory cytokine IL-21 correlated with mRNA expression of CD20, total IgG and also IL-10 in the TB lesions. Altogether, vitamin D-deficient TB patients expressed a weak antimicrobial response but an IL-21 associated expansion of IgG-secreting B cells combined with a rise in FoxP3(+) regulatory T cells at the local site of infection.

Topics: 25-Hydroxyvitamin D 2; Adult; Antigens, CD20; Antimicrobial Cationic Peptides; B-Lymphocytes; Calcifediol; Cathelicidins; Female; Forkhead Transcription Factors; Granuloma; Humans; Immunoglobulin G; Interleukin-10; Interleukins; Lung; Male; Middle Aged; Mycobacterium tuberculosis; T-Lymphocytes, Regulatory; Tuberculosis, Pulmonary; Vitamin D Deficiency

Decreased bone density secondary to osteoporosis and osteomalacia represents a significant risk factor for bony fracture and spinal instrumentation failure. We evaluated the incidence of vitamin D deficiency in patients undergoing elective spinal instrumentation to investigate which patient-level risk factors are associated with deficient vitamin D levels.. Serum 25-OH vitamin D levels were evaluated postoperatively (<72 hours) in patients undergoing elective spinal fusion from 2011 through 2012. Patients >18 years with a diagnosis of degenerative spinal spondylosis or spinal instability treated with spinal fusion were included. Risk factors for vitamin D deficiency (<20 ng/mL) were analyzed using univariate and multiple logistic regression to identify independent predictors of deficiency.. The mean preoperative neck and Oswestry disability indexes of the 230 consecutive patients (mean, 57 ± 13.9 years) were 21.0 ± 9.8 and 22.2 ± 8.5, respectively. Mean 25-OH vitamin D level was 25.9 ± 12.4 ng/mL (range, 6-77 ng/mL). Sixty-nine (30.0%) patients had laboratory-confirmed vitamin D deficiency and 89 (38.9%) had laboratory-confirmed vitamin D insufficiency (20-30 ng/mL). The risk of vitamin D deficiency was greater in men (odds ratio [OR] 2.53; P = 0.009), patients aged 40-60 years (OR 2.45; P = 0.018), and those who had body mass index >40 (OR 7.55; P = 0.004), an existing diagnosis of diabetes (OR 3.29; P = 0.019), or no vitamin D supplementation (OR 4.96; P = 0.043).. Vitamin D deficiency was common in patients with degenerative spondylosis undergoing spinal fusion. Middle-aged patients, men, the morbidly obese, those with a history of diabetes, and those with no history of supplementation had a higher incidence of vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Body Mass Index; Confounding Factors, Epidemiologic; Cross-Sectional Studies; Diabetes Complications; Elective Surgical Procedures; Female; Humans; Logistic Models; Male; Medical Records; Middle Aged; Obesity, Morbid; Odds Ratio; Osteoporosis; Predictive Value of Tests; Prevalence; Retrospective Studies; Risk Assessment; Risk Factors; Spinal Fusion; Spondylosis; United States; Vitamin D Deficiency; Vitamins

An inverse association between Parkinson disease (PD) and total vitamin D levels has been reported, but whether vitamin D from different sources, that is, 25(OH)D2 (from diet and supplements) and 25(OH)D3 (mainly from sunlight exposure), all contribute to the association is unknown. Plasma total 25(OH)D, 25(OH)D2, and 25(OH)D3 levels were measured by liquid chromatography-tandem mass spectrometry in PD patients (n = 478) and controls (n = 431). Total 25(OH)D was categorized by clinical insufficiency or deficiency; 25(OH)D2 and 25(OH)D3 were analyzed in quartiles. Vitamin D deficiency (total 25[OH]D < 20 ng/mL) and vitamin D insufficiency (total 25[OH]D < 30 ng/mL) are associated with PD risk (odds ratio [OR] = 2.6 [deficiency] and 2.1 [insufficiency]; P < 0.0001), adjusting for age, sex, and sampling season. Both 25(OH)D2 and 25(OH)D3 levels are inversely associated with PD (P(trend) < 0.0001). The association between 25(OH)D2 and PD risk is largely confined to individuals with low 25(OH)D3 levels (P(trend) = 0.0008 and 0.12 in individuals with 25[OH]D3 < 20 ng/mL and 25[OH]D3 ≥ 20 ng/mL, respectively). Our data confirm the association between vitamin D deficiency and PD, and for the first time demonstrate an inverse association of 25(OH)D2 with PD. Given that 25(OH)D2 concentration is independent of sunlight exposure, this new finding suggests that the inverse association between vitamin D levels and PD is not simply attributable to lack of sunlight exposure in PD patients with impaired mobility. The current study, however, cannot exclude the possibility that gastrointestinal dysfunction, a non-motor PD symptom, contributes to the lower vitamin D2 levels in PD patients.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Chromatography, Liquid; Female; Humans; Logistic Models; Male; Middle Aged; Parkinson Disease; Retrospective Studies; Tandem Mass Spectrometry; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Female; Humans; Male; Parkinson Disease; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Female; Humans; Male; Models, Biological; Skin; Skin Pigmentation; Ultraviolet Rays; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Female; Humans; Male; Models, Biological; Skin; Skin Pigmentation; Ultraviolet Rays; Vitamin D Deficiency

Xeroderma pigmentosum (XP) is a rare autosomal recessive disease characterized by defective repair of ultraviolet (UV) irradiation-induced DNA damage and high risk of skin cancer. Thus, these patients require strict photoprotection. Considering the importance of UV-mediated cutaneous vitamin D production, such rigorous photoprotection would cause vitamin D deficiency. Then, we have studied the vitamin D status in patients with XP-A, a group requiring the most strict photoprotection.. Twenty-one patients with XP-A (aged 6-25) were evaluated for their vitamin D intake, serum levels of 25-hydroxy-vitamin D (25OHD) and parathyroid hormone (PTH). Vitamin D intake was assessed by a 2-day food weighing method.. Median dietary intake of vitamin D was 4.1 μg/day, and the median concentrations of serum 25OHD and PTH were 7.7 and 49.9 pg/ml, respectively. In 76% of the patients, serum 25OHD level was lower than 10 ng/ml, indicating vitamin D deficiency. Vitamin D intake and serum 25OHD level were significantly lower in patients under enteral nutrition (EN) than those with oral intake (OI). Multivariate analyses revealed that EN was a significant predictor of decreased serum 25OHD level (β coefficient=-0.59, P=0.03).. Vitamin D deficiency is highly prevalent in XP-A patients, and supplementation should be considered to avoid unfavorable skeletal consequences in these patients. In addition, determination of dietary vitamin D requirement has been a difficult work issue in the decision of dietary reference intakes (DRIs) because of its cutaneous production. Data from XP patients would yield useful information for the determination of DRIs for vitamin D.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Calcifediol; Child; Combined Modality Therapy; Cross-Sectional Studies; Female; Hospitals, University; Humans; Japan; Life Style; Male; Nutritional Status; Outpatient Clinics, Hospital; Parathyroid Hormone; Patient Compliance; Prevalence; Risk; Skin Neoplasms; Sunscreening Agents; Vitamin D Deficiency; Xeroderma Pigmentosum; Young Adult

In adults, vitamin D deficiency is common in patients with nonalcoholic fatty liver disease (NAFLD) and has been associated with the severity of histology. There are known differences between adult and pediatric NAFLD, with little data regarding the relation between vitamin D and pediatric NAFLD. The aim of the present study was to examine the relation between vitamin D levels and NAFLD in children.. Clinical and histological data were used from children ages 2 to 18 years with biopsy-proven NAFLD enrolled in the Nonalcoholic Steatohepatitis Clinical Research Network studies. 25(OH) vitamin D levels were measured from serum. Data examined included demographics, anthropometrics, laboratory markers, and liver histology. Data were analyzed using 3 categories of vitamin D level: deficient (≤ 20 ng/mL), insufficient (21-29 ng/mL), and sufficient (≥ 30 ng/mL).. A total of 102 children were studied. There was a high prevalence (80/102, 78%) of vitamin D deficiency or insufficiency; however, there were no significant associations between vitamin D level and the histological characteristics or severity of NAFLD. Significantly higher levels of triglycerides were found in those with vitamin D deficiency (P = 0.004), but there was no association with other features of the metabolic syndrome.. There is a high prevalence of vitamin D deficiency and insufficiency in children with biopsy-proven NAFLD; however, no association was found between vitamin D deficiency and the severity of disease on biopsies. This differs from adult NAFLD studies in which vitamin D deficiency correlates with histological severity, suggesting differences in the risk factors for or consequences of pediatric NAFLD.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adolescent Nutritional Physiological Phenomena; Biomarkers; Biopsy; Calcifediol; Child; Child Nutritional Physiological Phenomena; Child, Preschool; Cross-Sectional Studies; Humans; Hypertriglyceridemia; Liver; Liver Cirrhosis; Non-alcoholic Fatty Liver Disease; Nutritional Status; Prevalence; Severity of Illness Index; United States; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Female; Humans; Male; Spinal Fusion; Spondylosis; Vitamin D Deficiency; Vitamins

There has been a surge of interest in the cardiovascular effects of vitamin D (25(OH)D), preventing the processes leading to vascular wall degeneration and coronary artery disease (CAD). Gender differences have been suggested for vitamin D status, with a higher rate of deficiency occurring especially in post-menopausal women, increasing the risk of bone fractures and osteoporosis. However, to date, few studies have evaluated the differences in 25(OH)D levels according to gender and their impact on the extent of CAD, which was therefore the aim of the present study.. In patients undergoing coronary angiography, fasting samples were collected for the assessment of 25(OH)D levels. Significant CAD was defined as at least one vessel stenosis >50%, while severe CAD was defined as left main and/or three-vessel disease. Of the 1811 patients included, 530 (29.3%) were females, who displayed older age (p < 0.001), higher rate of renal failure (p < 0.001), hypertension (p = 0.05), treatment with angiotensin-receptor blockers (p = 0.03) and diuretics (p < 0.001), acute presentation (p < 0.001), higher platelet count (p < 0.001), glycosylated haemoglobin (p = 0.02) and cholesterol (p = 0.001), but an inverse relationship with smoking (p < 0.001), previous cardiovascular events (p < 0.001), treatment with statins and acetylsalicylic acid (ASA) (p < 0.001), body mass index (p = 0.002), haemoglobin (p < 0.001), leucocytes (p = 0.03) and triglycerides (p < 0.001). Female gender was associated with lower vitamin D levels (14.5 ± 10.9 vs. 15.9 ± 9.5, p = 0.007) and independently associated with severe vitamin D deficiency (41.9% vs. 30.4%, p < 0.001; adjusted odds ratio (OR) (95% confidence interval (CI)) = 1.42 (1.08-1.87), p = 0.01). Lower tertiles of vitamin D were associated with an increased prevalence and severity of CAD in females (adjusted OR (95% CI = 1.26 (1.10-1.44), p = 0.001 for CAD; adjusted OR (95% CI) = 1.6 (1.39-1.87), p < 0.001 for severe CAD). In males, vitamin D status was independently related to the prevalence (adjusted OR (95% CI) = 1.28 (1.02-1.61), p = 0.03) of CAD, but not the extent of CAD (adjusted OR (95% CI) = 1.02 (0.86-1.2), p = 0.84).. Gender significantly affects vitamin D status. The lower 25(OH)D levels observed in females, as compared to males, play a more relevant role in conditioning the severity of CAD.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Calcifediol; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Cross-Sectional Studies; Female; Humans; Italy; Male; Middle Aged; Nutritional Status; Prevalence; Prospective Studies; Severity of Illness Index; Sex Characteristics; Vitamin D Deficiency

Vitamin D deficiency has been associated with increased risk for cardiovascular (CV) disease, but the possible effects of Vitamin D on cardiac structure and function are not well characterized.. The correlation between 25-hydroxyvitamin D levels and metabolic and cardiac echocardiographic parameters was studied in ARTEMIS study population including 831diabetic and 659 non-diabetic patients with stable coronary artery disease (CAD). Low levels of Vitamin D were associated with high BMI (p < 0.001), high total and LDL cholesterol and triglyceride levels (p < 0.001 for all) in both diabetics and non-diabetics. Among non-diabetic patients, low Vitamin D was also associated independently with elevated systolic and diastolic blood pressure (p < 0.005). Low Vitamin D levels were independently associated with reduced left ventricular (LV) ejection fraction (p < 0.005) and increased left atrial diameter (p < 0.03) measured by cardiac ultrasound by 2-dimensional echo. In the non-diabetic group, low Vitamin D levels were associated with impaired LV filling (high E/E') (p < 0.03) and low E/A mitral flow pattern measured by Doppler echocardiography (p < 0.05). Among diabetics, low Vitamin D levels were also related to increased LV end-systolic diameter (p < 0.05) and right ventricular diameter (p < 0.005). The association between LV diastolic filling (E/E') and Vitamin D levels was significant (p < 0.01) after adjustment for the commonly recognized risk factors of diastolic dysfunction in linear regression analysis.. Low Vitamin D is associated with several major cardiovascular risk factors and cardiac structural changes including impaired systolic and diastolic function, which together may explain the association of low Vitamin D to worse cardiovascular outcome.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Calcifediol; Cardiovascular Diseases; Cohort Studies; Coronary Artery Disease; Echocardiography, Doppler; Female; Finland; Heart; Heart Atria; Heart Ventricles; Humans; Male; Middle Aged; Nutritional Status; Organ Size; Prevalence; Risk Factors; Stroke Volume; Ventricular Dysfunction, Left; Vitamin D Deficiency

We investigated the vitamin D status of Korean women during pregnancy and assessed the effects of vitamin D deficiency on two pregnancy outcomes; preterm births and the births of small for gestational age. We measured the serum 25-hydroxyvitamin D levels in 220 pregnant Korean women who were recruited prospectively and compared these levels with those of 500 healthy non-pregnant women. We analyzed vitamin D status according to patient demographics, season, and obstetrical characteristics; moreover, we also assessed pregnancy outcomes. The overall prevalence of vitamin D deficiency(<20 ng/mL) in pregnant women and healthy non-pregnant women was 77.3% and 79.2%; respectively; and the prevalence of severe vitamin D deficiency (<10 ng/mL) was 28.6% and 7.2%; respectively (p < 0.05). Vitamin D deficiency was more prevalent in the winter (100%) than in the summer (45.5%) in pregnant Korean women. A higher risk of vitamin D deficiency was observed in the first trimester than in the third trimester (adjusted OR 4.3; p < 0.05). No significant association was observed between vitamin D deficiency and any of the pregnancy outcomes examined. Further research focusing on the long-term consequences of vitamin D deficiency during pregnancy in Korean women is warranted.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cohort Studies; Female; Fetal Growth Retardation; Humans; Infant, Newborn; Male; Maternal Nutritional Physiological Phenomena; Nutritional Status; Pregnancy; Pregnancy Complications; Pregnancy Trimester, First; Premature Birth; Prevalence; Prospective Studies; Republic of Korea; Risk Factors; Seasons; Urban Health; Vitamin D Deficiency; Young Adult

The effect of vitamin D pertinent to cardiovascular health on the heart itself is considered to shift toward an anti-inflammatory response in chronic heart failure (CHF); however, its underlying mechanism is not completely understood. In this study, we demonstrated that plasma 25(OH)D level, negatively associated with NT-ProBNP, correlated with the decreased Treg in CHF compared to the patients with other cardiovascular diseases and healthy and older donors. Naïve Treg cell (CD4(+)CD45RA(+)Foxp3(lo)T) subset, rather than whole Treg cells, contributes to the reduction of Treg in CHF. 1,25(OH)2D treatment maintained partial expression of CD45RA on CD4(+)T cell after αCD3/CD28 monoclonal antibodies activation and ameliorated the impaired CD4(+)CD45RA(+)T cell function from CHF patients through upregulating Foxp3 expression and IL-10 secretion in vitro. Low level of vitamin D receptor (VDR) was detected in CD4(+)CD45RA(+)T cell of CHF than control, while 1,25(OH)2D treatment increased the VDR expression to exert its immunosuppression on T cell. The results of this study might provide tangible evidence to our knowledge of the impact of vitamin D supplementation on naïve Tregs, which may offer new means of preventing and treating CHF.

Topics: 25-Hydroxyvitamin D 2; Aged; Anti-Inflammatory Agents; CD4 Antigens; Female; Flow Cytometry; Heart Failure; Humans; Inflammation; Interferon-gamma; Interleukin-10; Interleukin-17; Leukocyte Common Antigens; Lymphocyte Count; Male; Middle Aged; T-Lymphocytes, Regulatory; Th17 Cells; Vitamin D Deficiency

In Romania (latitude 48°15'N to 43°40'N), vitamin D supplementation is common practice mostly in infants 0-1 year old. No published information is available regarding epidemiological data on vitamin D status in the Romanian population for a wide age range and geographical territory. In this context, we aimed to evaluate the seasonal and age variation of vitamin D status in a large Romanian population.. 6631 individuals from across Romania had performed 7544 vitamin D assessments (2012-2014) in a chain of private laboratories. Vitamin D (25-hydroxyvitamin D2 and 25-hydroxyvitamin D3) was measured using High Performance Liquid Chromatography. Vitamin D levels were classified as severe deficiency<10 ng/mL, deficiency 10-20 ng/mL, insufficiency 21-29 ng/mL, sufficiency ≥ 30 ng/mL and potentially harmful>100 ng/ml.. Male to female ratio was 1:2.9. Age ranged from 0 to 85 years. Mean vitamin D levels increased from April (26.3n g/ml) to September (35.6 ng/ml) and decreased from October (33.5 ng/ml) to March (24.4 ng/ml). Overall 40% had sufficient vitamin D, while the rest were insufficient 33%, deficient 22%, severely deficient 4% and 1% potentially harmful (of them 81% under 1 year old). Males compared to females showed higher percentages of sufficiency (47% vs. 38%). Children 0- 2 years presented the highest percentage of vitamin D sufficiency (77%). Lowest percentages (21%) of sufficiency were in people 80-84 years.. In Romania, suboptimal vitamin D levels are common (59%), especially in older age, wintertime and in women. Vitamin D supplementation would be most warranted from January to April in the Romanian population. 25-hydroxyvitamin D levels > 100 ng/ml were relatively prevalent in children 0-1 year old (17.3%). This was attributed to supplementation errors and the fact that high-risk individuals were more likely to visit for medical check-up. Nonetheless, it stresses the need to increase awareness of the importance of preventing Vitamin D supplementation administration errors in the young.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Calcifediol; Calcium; Child; Child, Preschool; Cross-Sectional Studies; Female; Humans; Infant; Infant, Newborn; Male; Middle Aged; Parathyroid Hormone; Romania; Seasons; Vitamin D; Vitamin D Deficiency; Young Adult

Low circulating levels of total vitamin D [25(OH)D] and 25(OH)D3 have been associated with vascular complications in few studies on individuals with type 1 diabetes. However, these measures are affected by UV light exposure. Circulating 25(OH)D2, however, solely represents dietary intake of vitamin D2, but its association with complications of diabetes is currently unknown. We investigated the associations between 25(OH)D2 and 25(OH)D3 and the prevalence of albuminuria, retinopathy and cardiovascular disease (CVD) in individuals with type 1 diabetes.. We measured circulating 25(OH)D2 and 25(OH)D3 in 532 individuals (40 ± 10 years old, 51 % men) with type 1 diabetes who participated in the EURODIAB Prospective Complications Study. Cross-sectional associations of 25(OH)D2 and 25(OH)D3 with albuminuria, retinopathy and CVD were assessed with multiple logistic regression analyses adjusted for age, sex, season, BMI, smoking, HbA1c, total-HDL-cholesterol-ratio, systolic blood pressure, antihypertensive medication, eGFR, physical activity, alcohol intake, albuminuria, retinopathy and CVD, as appropriate.. Fully adjusted models revealed that 1 nmol/L higher 25(OH)D2 and 10 nmol/L higher 25(OH)D3 were associated with lower prevalence of macroalbuminuria with ORs (95 % CI) of 0.56 (0.43;0.74) and 0.82 (0.72;0.94), respectively. These vitamin D species were not independently associated with microalbuminuria, non-proliferative and proliferative retinopathy or CVD.. In individuals with type 1 diabetes, both higher 25(OH)D2 and 25(OH)D3 are associated with a lower prevalence of macroalbuminuria, but not of retinopathy and CVD. Prospective studies are needed to further examine the associations between 25(OH)D2 and 25(OH)D3 and the development of microvascular complications and CVD in type 1 diabetes.

Topics: 25-Hydroxyvitamin D 2; Adult; Albuminuria; Calcifediol; Cardiovascular Diseases; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Retinopathy; Female; Humans; Logistic Models; Male; Middle Aged; Prospective Studies; Risk Factors; Vitamin D Deficiency

This study was designed to evaluate vitamin D status with separate determination of 25-OH D2 and 25-OH D3 and its relationship to vitamin D binding protein (VDBP) in patients with chronic kidney disease (CKD) and long-term haemodialysis patients (HD).. 45 CKD patients, 103 HD patients, and 25 controls (C) were included. Plasma vitamin D concentrations were determined using chromatography and VDBP in serum and urine in CKD using enzyme immunoassay.. Plasma vitamin D levels were lower in CKD (30.16 ± 16.74 ng/mL) and HD (18.85 ± 15.85 ng/mL) versus C (48.72 ± 18.35 ng/mL), P < 0.0001. 25-OH D3 was the dominant form of vitamin D. Serum VDBP was higher in CKD (273.2 ± 93.8 ug/mL) versus C (222 ± 87.6 ug/mL) and HD (213.8 ± 70.9 ug/mL), P = 0.0003. Vitamin D/VDBP ratio was the highest in C and the lowest in HD; however, there was no correlation between vitamin D and VDBP. Urinary concentration of VDBP in CKD (0.25 ± 0.13 ug/mL) correlated with proteinuria (r = 0.43, P = 0.003).. Plasma levels of vitamin D are decreased in CKD patients and especially in HD patients. 25-OH D3 was the major form of vitamin D. Despite urinary losses of VDBP, CKD patients had higher serum VDBP concentrations, indicating compensatory enhanced production. Vitamin D binding protein is not involved in vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Calcifediol; Female; Humans; Male; Middle Aged; Renal Insufficiency, Chronic; Vitamin D; Vitamin D Deficiency; Vitamin D-Binding Protein

Vitamin D is a pivotal factor in calcium homeostasis and exerts immunomodulatory effects. Hypovitamin D has been demonstrated in systemic sclerosis (SSc) patients and may be related to more severe disease of longer duration and with extensive skin involvement.. To seek anti-vitamin D antibodies in SSc patients, as found by previous research in patients with systemic lupus erythematosus (SLE).. The study included 54 SSc patients and 41 volunteers. Immunoglobulin (Ig) G and IgM autoantibody levels against 25(OH)D and 1,25(OH)D were obtained from patients and controls and were compared. SSc patients were assessed for autoantibody profile and disease severity.. Vitamin D antibodies were present in 87% of SSc patients and 42% of controls. Higher levels of anti-25(OH)D IgM antibodies were detected in SSc patients compared to controls (0.48 ± 0.22 vs. 0.29 ± 0.29, respectively, P = 0.002); however, IgG levels were lower in the SSc patients. No such discriminative. effect was found regarding anti-1,25(OH)D antibodies between SSc and controls. No correlation was found between,vitamin D antibodies and other autoantibodies, disease severity, or target organ damage.. To the best of our knowledge; this is the first study of these novel, anti-vitamin D antibodies in SSc patients and the first time a correlation between IgM 25(OH) vitamin D antibodies and scleroderma has been identified. Further research on the pathophysiological significance and therapeutic potential of vitamin D is required.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Autoantibodies; Calcitriol; Female; Humans; Immunoglobulin G; Immunoglobulin M; Male; Middle Aged; Scleroderma, Systemic; Severity of Illness Index; Statistics as Topic; Vitamin D Deficiency

To enable food-based strategies for the prevention of vitamin D deficiency to be evidence-based, there is a need to develop integrated predictive models of population serum 25-hydroxyvitamin D [25(OH)D] that are responsive to both solar and dietary inputs of vitamin D.. The objectives of this work were to develop and validate an integrated mathematical model with the use of data on UVB availability, exposure, and dietary intake to predict serum 25(OH)D concentrations in a nationally representative sample of adults, and then test the model's performance with the use of 3 hypothetical fortification scenarios as exemplars.. Data on UVB availability and hours of sunlight in Ireland were used in a mathematical model to predict serum 25(OH)D in Irish adults aged 18-64 y. An equation from our dose-related vitamin D supplementation trial in adults was developed and integrated into the model, which allowed us to predict the impact of changes in dietary vitamin D on the contribution to annual serum 25(OH)D concentrations, accounting for seasonality of UVB availability. Recently published estimates of the impact of 3 vitamin D food fortification scenarios on vitamin D intake in a representative sample of Irish adults were used in the model as a test.. The UVB- and vitamin D intake-serum 25(OH)D components of the integrated model were both validated with the use of independent data. The model predicted that the percentage of vitamin D deficiency [serum 25(OH)D <30 nmol/L] in the adult population during an extended winter period was 18.1% (vs. 18.6% measured), which could be reduced in a stepwise manner with the incorporation of an increased number of vitamin D-fortified foods, down to 6.6% with the inclusion of enhanced fortified dairy-related products, fat spreads, fruit juice and drinks, and cereal products.. Mathematical models have the ability to inform how vitamin D food fortification in various constructs may affect population serum 25(OH)D concentrations and the prevalence of vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Calcifediol; Diet; Dietary Supplements; Food, Fortified; Humans; Ireland; Kinetics; Middle Aged; Models, Biological; Nutrition Policy; Seasons; Skin; Sunlight; Ultraviolet Rays; Vitamin D; Vitamin D Deficiency; Young Adult

To our knowledge, no studies have reported on the long-term variability of vitamin D status in adolescents.. To determine whether tracking of vitamin D status occurs in healthy adolescents, we assessed the variability of 25-hydroxyvitamin D [25(OH)D] every 2 y over a 10-y period in a longitudinal cohort of adolescents living in Johannesburg, South Africa (latitude 26°S).. Healthy adolescents who had blood samples available on ≥3 occasions between 11 and 20 y of age were included in the study. Of the cohort of 504 children, 99 met the criteria. The mean 25(OH)D concentration at each time point was measured, and the individual 25(OH)D z scores based on year 11 values were used as the reference. All 25(OH)D concentrations for a subject were measured in a single assay.. No significant correlation was found between 25(OH)D in the earlier and later years of adolescence, although significant correlations were found between year 11 and year 13 (r = 0.71, P < 0.0001) and between years 15, 17, and 20 (r ≥ 0.65, P < 0.0001). The percentage of adolescents whose 25(OH)D concentration changed by >20 nmol/L from year 11 was calculated for all age groups: 12% of the cohort had a change of >20 nmol/L at 13 y of age compared with 46% at 20 y of age. Just more than one-half (53%) of the cohort changed their category of vitamin D status between the ages of 11 and 20 y, and one-third of adolescents changed from being replete to insufficient over the same period.. The data suggest that the measurement of 25(OH)D at a single time point does not reflect the long-term vitamin D status of an adolescent. These findings may cast doubt on the veracity of those studies that suggest an association of vitamin D status with various disease states in which vitamin D status was measured only once.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adolescent Development; Adolescent Nutritional Physiological Phenomena; Adult; Calcifediol; Child; Child Development; Child Nutritional Physiological Phenomena; Cohort Studies; Female; Humans; Incidence; Longitudinal Studies; Male; Models, Biological; Nutritional Status; Prospective Studies; Severity of Illness Index; South Africa; Urban Health; Vitamin D Deficiency; Young Adult

The role of maternal 25-hydroxyvitamin D [25(OH)D] in fetal development is uncertain, and findings of observational studies have been inconsistent. Most studies have assessed 25(OH)D only one time during pregnancy, but to our knowledge, the tracking of an individual's 25(OH)D during pregnancy has not been assessed previously.. We determined the tracking of serum 25(OH)D from early to late pregnancy and factors that influence this.. The Southampton Women's Survey is a prospective mother-offspring birth-cohort study. Lifestyle, diet, and 25(OH)D status were assessed at 11 and 34 wk of gestation. A Fourier transformation was used to model the seasonal variation in 25(OH)D for early and late pregnancy separately, and the difference between the measured and seasonally modeled 25(OH)D was calculated to generate a season-corrected 25(OH)D. Tracking was assessed with the use of the Pearson correlation coefficient, and multivariate linear regression was used to determine factors associated with the change in season-corrected 25(OH)D.. A total of 1753 women had 25(OH)D measured in both early and late pregnancy. There was a moderate correlation between season-corrected 25(OH)D measurements at 11 and 34 wk of gestation (r = 0.53, P < 0.0001; n = 1753). Vitamin D supplementation was the strongest predictor of tracking; in comparison with women who never used supplements, the discontinuation of supplementation after 11 wk was associated with a reduction in season-corrected 25(OH)D (β = -7.3 nmol/L; P < 0.001), whereas the commencement (β = 12.6 nmol/L; P < 0.001) or continuation (β = 6.6 nmol/L; P < 0.001) of supplementation was associated with increases in season-corrected 25(OH)D. Higher pregnancy weight gain was associated with a reduction in season-corrected 25(OH)D (β = -0.4 nmol · L(-1) · kg(-1); P = 0.015), whereas greater physical activity (β = 0.4 nmol/L per h/wk; P = 0.011) was associated with increases.. There is a moderate tracking of 25(OH)D status through pregnancy; factors such as vitamin D supplementation, weight gain, and physical activity are associated with changes in season-corrected 25(OH)D from early to late gestation. These findings have implications for study designs and analyses and approaches to intervention studies and clinical care.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cohort Studies; Dietary Supplements; England; Female; Fourier Analysis; Humans; Longitudinal Studies; Maternal Nutritional Physiological Phenomena; Models, Biological; Nutritional Status; Pregnancy; Pregnancy Complications; Pregnancy Maintenance; Prospective Studies; Risk; Seasons; Vitamin D; Vitamin D Deficiency; Young Adult

The objective of this study was to examine whether high serum 25-hydroxyvitamin D (25(OH)D) concentration was associated with high skeletal muscle mass, taking into account the effects of sex and age among the participants of the Korea National Health and Nutrition Examination Survey (KNHANES) aged 40 years or older. This was a cross-sectional study using data from the 2009 to 2010 KNHANES; a total of 8406 subjects (3671 men and 4735 women) were included. The appendicular skeletal muscle mass index (ASMMI, kg/m2) was estimated to measure the skeletal muscle mass. Hypovitaminosis was classified when the level of serum 25(OH)D was <20 ng/ml. The general linear model adjusted for confounding factors was used to determine differences in means of ASMMI by 25(OH)D status. The mean values of ASMMI were higher for men when compared with women. Women had a greater proportion of hypovitaminosis (71·1%) compared with men (53·2%). After adjusting for multiple factors, men were seen to have significant differences in ASMMI based on 25(OH)D status regardless of age, showing a lower mean value of ASSMI in those with hypovitaminosis. However, there was no difference in ASMMI by 25(OH)D status among women in both younger and older age groups. In conclusion, we found that there might be a positive relationship between 25(OH)D and skeletal muscle mass in men, indicating that interventions to improve 25(OH)D levels that are aimed at increasing muscle mass could be beneficial for men with more rapid decreased rate of skeletal muscle mass.

Topics: 25-Hydroxyvitamin D 2; Absorptiometry, Photon; Adult; Age Factors; Aged; Aged, 80 and over; Calcifediol; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Muscle Development; Muscle, Skeletal; Muscular Atrophy; Nutrition Surveys; Nutritional Status; Republic of Korea; Risk; Sarcopenia; Sex Factors; Vitamin D Deficiency; Whole Body Imaging

The Canadian Health Measures Survey (CHMS) is an ongoing cross-sectional national survey that includes a measure of 25-hydroxyvitamin D [25(OH)D] by immunoassay. For cycles 1 and 2, the collection period occurred approximately every 2 y, with a new sample of ∼5600 individuals.. The goal was to standardize the original 25(OH)D CHMS values in cycles 1 and 2 to the internationally recognized reference measurement procedures (RMPs) developed by the US National Institute for Standards and Technology (NIST) and Ghent University, Belgium.. Standardization was accomplished by using a 2-step procedure. First, serum samples corresponding to the original plasma samples were remeasured by using the currently available immunoassay method. Second, 50 serum samples with known 25(OH)D values assigned by the NIST and Ghent reference method laboratories were measured by using the currently available immunoassay method. The mathematical models for each step-i.e., 1) YCurrent = XOriginal and 2) YNIST-Ghent = XCurrent -were estimated by using Deming regression, and the 2 models were solved to obtain a single equation for converting the "original" values to NIST-Ghent RMP values.. After standardization (cycles 1 and 2 combined), the percentage of Canadians with 25(OH)D values <40 nmol/L increased from 16.4% (original) to 19.4% (standardized), and values <50 nmol/L increased from 29.0% (original) to 36.8% (standardized). The 25(OH)D standardized distributions (cycles 1 and 2 analyzed separately) were similar across age and sex groups; slightly higher values were associated with cycle 2 in the young and old. This finding contrasts with the original data, which indicated that cycle 2 values were lower for all age groups.. The shifts in 25(OH)D distribution brought about by standardization indicate its importance in drawing correct conclusions about potential population deficiencies and insufficiencies and in permitting the comparison of distributions between national surveys.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Automation, Laboratory; Calcifediol; Canada; Child; Cross-Sectional Studies; Early Diagnosis; Female; Humans; Immunoassay; Male; Middle Aged; Models, Statistical; Nutrition Assessment; Nutrition Surveys; Reference Values; Vitamin D Deficiency; Young Adult

Epidemiological studies have reported that vitamin D deficiency is associated with inflammatory disease. Smoking is a well-known risk factor for inflammation. However, few studies have investigated the interactive effect of vitamin D deficiency and smoking on inflammation. This study aims to investigate the interaction of vitamin D and smoking with inflammatory markers in the urban elderly.. We used data from the Korean Elderly Environmental Panel Study, which began in August 2008 and ended in August 2010, and included 560 Koreans ≥60 years old living in Seoul. Data was collected via questionnaires that included items about smoking status at the first visit. Vitamin D levels, high-sensitivity C-reactive protein (hs-CRP), and white blood cell (WBC) counts were repeatedly measured up to three times.. The association of vitamin D and hs-CRP was significant after adjusting for known confounders (β=-0.080, p=0.041). After separate analysis by smoking status, the association of vitamin D deficiency and hs-CRP in smokers was stronger than that in nonsmokers (smokers: β=-0.375, p=0.013; non-smokers: β=-0.060, p=0.150). Smoking status was an effect modifier that changed the association between vitamin D deficiency and hs-CRP (interaction estimate: β=-0.254, p=0.032). Vitamin D was not significantly associated with WBC count (β=0.003, p=0.805).. Vitamin D deficiency was associated with hs-CRP in the urban elderly. Smoking status was an effect modifier of this association. Vitamin D deficiency was not significantly associated with WBC count.

Topics: 25-Hydroxyvitamin D 2; Aged; Biomarkers; Body Mass Index; C-Reactive Protein; Female; Humans; Inflammation; Leukocyte Count; Male; Middle Aged; Smoking; Urban Population; Vitamin D; Vitamin D Deficiency

In a prospective cohort study, the association between maternal vitamin D status during pregnancy and offspring forearm fractures during childhood and adolescence was analysed in 30 132 mother and child pairs recruited to the Danish National Birth Cohort between 1996 and 2002. Data on characteristics, dietary factors and lifestyle factors were collected on several occasions during pregnancy. We analysed the association between predicted vitamin D status, based on a subsample with 25-hydroxyvitamin D (25(OH)D) biomarker measurements (n 1497) from gestation week 25, and first-time forearm fractures among offspring between birth and end of follow-up. Diagnoses were extracted from the Danish National Patient Register. Multivariable Cox regression models using age as the underlying time scale indicated no overall association between predicted vitamin D status (based on smoking, season, dietary and supplementary vitamin D intake, tanning bed use and outdoor physical activity) in pregnancy and offspring forearm fractures. Likewise, measured 25(OH)D, tanning bed use and dietary vitamin D intake were not associated with offspring forearm fractures. In mid-pregnancy, 91 % of the women reported intake of vitamin D from dietary supplements. Offspring of women who took >10 µg/d in mid-pregnancy had a significantly increased risk for fractures compared with the reference level of zero intake (hazard ratios (HR) 1·31; 95% CI 1·06, 1·62), but this was solely among girls (HR 1·48; 95% CI 1·10, 2·00). Supplement use in the peri-conceptional period exhibited similar pattern, although not statistically significant. In conclusion, our data indicated no protective effect of maternal vitamin D status with respect to offspring forearm fractures.

Topics: 25-Hydroxyvitamin D 2; Biomarkers; Calcifediol; Cohort Studies; Denmark; Female; Fetal Development; Follow-Up Studies; Forearm; Fractures, Bone; Humans; Infant, Newborn; Male; Maternal Nutritional Physiological Phenomena; Nutritional Status; Osteoporotic Fractures; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Third; Proportional Hazards Models; Prospective Studies; Registries; Risk; Vitamin D Deficiency

Vitamin D and iron deficiencies frequently co-exist. It is now appreciated that mechanistic interactions between iron and vitamin D metabolism may underlie these associations.. We examined interrelations between iron and vitamin D status and their regulatory hormones in pregnant adolescents, who are a group at risk of both suboptimal vitamin D and suboptimal iron status.. The trial was a prospective longitudinal study of 158 pregnant adolescents (aged ≤18 y). Maternal circulating biomarkers of vitamin D and iron were determined at midgestation (∼25 wk) and delivery (∼40 wk). Linear regression was used to assess associations between vitamin D and iron status indicators. Bivariate and multivariate logistic regressions were used to generate the OR of anemia as a function of vitamin D status. A mediation analysis was performed to examine direct and indirect relations between vitamin D status, hemoglobin, and erythropoietin in maternal serum.. Maternal 25-hydroxyvitamin D [25(OH)D] was positively associated with maternal hemoglobin at both midgestation and at delivery (P < 0.01 for both). After adjustment for age at enrollment and race, the odds of anemia at delivery was 8 times greater in adolescents with delivery 25(OH)D concentrations <50 nmol/L than in those with 25(OH)D concentrations ≥50 nmol/L (P <0.001). Maternal 25(OH)D was inversely associated with erythropoietin at both midgestation (P <0.05) and delivery (P <0.001). The significant relation observed between 25(OH)D and hemoglobin could be explained by a direct relation between 25(OH)D and hemoglobin and an indirect relation that was mediated by erythropoietin.. In this group of pregnant adolescents, suboptimal vitamin D status was associated with increased risk of iron insufficiency and vice versa. These findings emphasize the need for screening for multiple nutrient deficiencies during pregnancy and greater attention to overlapping metabolic pathways when selecting prenatal supplementation regimens.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Anemia, Iron-Deficiency; Biomarkers; Calcifediol; Cohort Studies; Cross-Sectional Studies; Erythropoietin; Female; Hemoglobins; Humans; Linear Models; Longitudinal Studies; Maternal Nutritional Physiological Phenomena; New York; Nutritional Status; Pregnancy; Pregnancy Complications; Prospective Studies; Risk; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Female; Hospitalization; Humans; Male; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Humans; Reference Values; Vitamin D Deficiency

Considerable variation in 25-hydroxyvitamin D (25(OH)D) in populations worldwide that seems to be independent of latitude has been reported. Therefore, we aimed to assess vitamin D status of a mid-aged German general population and to identify its dietary, lifestyle, anthropometric, and genetic determinants.. 25(OH)D concentrations were measured by LC-MS/MS in plasma samples of a random subcohort of the German arm of the European Prospective Investigation into Cancer and Nutrition (EPIC) comprising 2,100 subjects aged 35-65 years. Associations between potential predictors and 25(OH)D were assessed by linear regression models.. 32.8% of the variance in 25(OH)D was explained by a multivariable regression model, with season being the by far strongest predictor (semi-partial R²: 14.6%). Sex, waist circumference, leisure time physical activity, smoking, polymorphisms in the GC, CYP2R1, and DHCR7 genes, supplement use, exogenous hormone use, alcohol consumption, egg consumption, and fish consumption were significantly associated with 25(OH)D concentrations as well. However, none of these factors explained >2.3% of the variance in 25(OH)D.. Even with a comprehensive set of genetic, anthropometric, dietary, and lifestyle correlates, not more than 32.8% of the variation in 25(OH)D could be explained in the EPIC-Germany study, implying that vitamin D prediction scores may not provide an appropriate proxy for measured 25(OH)D. Food intake was only a weak predictor of 25(OH)D concentrations, while a strong seasonal fluctuation in 25(OH)D was shown.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Calcifediol; Cohort Studies; Cross-Sectional Studies; Diet; Female; Germany; Humans; Life Style; Male; Middle Aged; Models, Biological; Nutrition Surveys; Nutritional Status; Prevalence; Prospective Studies; Seasons; Vitamin D Deficiency

Hypovitaminosis D has been linked with poor cognitive function, particularly in older adults, but studies lack a lifespan approach; hence, the effects of reverse causality remain unknown. In the present study, we aimed to assess the relationship between 25-hydroxyvitamin D (25(OH)D) concentrations and subsequent cognitive performance in mid-adulthood and the influence of earlier life factors, including childhood cognitive ability, on this association. Information for the present study was obtained from the members of the 1958 British birth cohort (n 6496). Serum 25(OH)D concentration, indicating vitamin D status, was measured at age 45 years. Verbal memory (immediate and delayed word recall), verbal fluency (animal naming) and speed of processing were tested at age 50 years. Information on childhood cognitive ability, educational attainment, vitamin D-related behaviours and other covariates was collected prospectively from participants throughout their life. Childhood cognitive ability and educational attainment by age 42 years were strongly correlated with cognitive performance at age 50 years and with several vitamin D-related behaviours in mid-adulthood, but not with 25(OH)D concentrations at age 45 years. Participants with both low (<25 nmol/l) and high (≥75 nmol/l) 25(OH)D concentrations at age 45 years performed significantly worse on immediate word recall. The associations attenuated after adjustment for childhood cognitive ability, education, and socio-economic position; however, for the immediate word recall test, there was a non-linear association with 25(OH)D after further adjustment for obesity, menopausal status, smoking, alcohol consumption, physical activity and depressive symptoms at age 45 years (P(curvature)=0·01). The present study demonstrated that 25(OH)D concentrations were non-linearly associated with immediate word recall in mid-life. A clarification of the level of 25(OH)D concentrations that is most beneficial for predicting better cognitive performance in mid-life is required.

Topics: 25-Hydroxyvitamin D 2; Aging; Calcifediol; Cognition; Cognition Disorders; Cohort Studies; Dietary Supplements; Educational Status; Female; Humans; Longitudinal Studies; Male; Memory, Short-Term; Middle Aged; Models, Statistical; Prospective Studies; Task Performance and Analysis; United Kingdom; Verbal Learning; Vitamin D; Vitamin D Deficiency

We report the presence of substantial concentrations of 3-epi-25(OH)D3 in two patients and a third patient with 3-epi-25(OH)D2.. The first patient, a 66-year-old female receiving cholecalciferol 4000 IU daily was originally found to have 53 ng/mL of 25(OH)D3 and almost an equal amount of 3-epi-25(OH)D3. Subsequently, the patient had four additional samples, each of which has similar levels of both 25(OH)D3 and 3-epi-25(OH)D3. The second patient, a 7-year-old male receiving cholecalciferol 1000 IU daily, had a 25(OH)D3 concentration of 37 ng/mL and 3-epi-25(OH)D3 of approximately 10 ng/mL. The third and most intriguing patient, a 55-year-old female was receiving ergocalciferol 50,000 IU twice weekly for approximately 3 months, at which time her serum 25(OH)D2 was 64 ng/mL and her 3-epi-25(OH)D2 was approximately 32 ng/mL. This patient's physician changed her vitamin D therapy to cholecalciferol 1000 IU daily, discontinuing ergocalciferol, and a second specimen was collected 5 months later. Analysis of this last specimen found both 25(OH)D3 and 25(OH)D2 at concentrations of 12 and 24 ng/mL respectively, plus corresponding 3-epimer peaks for both 25(OH)D3 and 25(OH)D2 observed chromatographically.. The presence of a substantial concentration of 3-epi-25(OH)D in these three patients documents that one cannot assume 3-epi is a trivial metabolite of 25(OH)D for all patients. In addition, the appearance of 3-epi-25(OH)D3 when the last patient changed her vitamin D supplementation from ergocalciferol to cholecalciferol demonstrates that the 3-epimer is probably an endogenous metabolite of 25(OH)D in humans.

Topics: 25-Hydroxyvitamin D 2; Aged; Child; Ergocalciferols; Female; Humans; Male; Middle Aged; Vitamin D; Vitamin D Deficiency

Low serum concentrations of 25-hydroxyvitamin D (25(OH)D) have been associated with poor physical function in older adults, but few, if any, studies have examined this relationship in the very old. Therefore, the purpose of this study is to examine this relationship in the very old. Serum 25(OH)D concentrations were obtained from 194 centenarians and near centenarians (98 years and older). The associations between 25(OH)D concentrations and measures of physical function were evaluated with unadjusted and adjusted regression models. We found that 35% of centenarians had 25(OH)D concentrations less than 50 nmol/L. Adjusted mean grip strength was lower for centenarians with 25(OH)D concentrations less than 75 nmol/L than for centenarians with higher concentrations (P<0.05). However, there were no differences in the Georgia Centenarian Study (GCS) Composite Scale, a global measure of physical function, between those with higher and lower 25(OH)D concentrations. We conclude that low 25(OH)D concentrations are associated with poor grip strength, but not GCS Composite Scale, in the very old. Considering the high burden of poor physical function in older adults, understanding the relationship between vitamin D and different measures of physical function, including strength, becomes increasingly important.

Topics: 25-Hydroxyvitamin D 2; Aged, 80 and over; Aging; Calcifediol; Cross-Sectional Studies; Female; Frail Elderly; Georgia; Geriatric Assessment; Hand Strength; Humans; Male; Muscle Weakness; Nutritional Status; Seasons; Vitamin D Deficiency

Vitamin D is shown to be a potent immunomodulator. Considering the potential role of low serum vitamin D levels in autoimmune disorder, we evaluated the association between Hashimoto's thyroiditis (HT) (with subclinical or overt hypothyroidism) and serum 25-hydroxyvitamin D (25OHD) levels in an Iranian population.. A total number of 86 individuals were enrolled. The case group included 41 patients with hypothyroid HT (overt or subclinical). The control group comprised 45 healthy euthyroid persons. Serum 25OHD levels were measured in all subjects.. control ratio of geometric means of 25OHD levels was 0.66 (95 % CI: 0.49-0.90; P = 0.008). There was a significant inverse association between serum 25OHD levels and HT (OR: 0.81 for 5 ng/ml increase in 25OHD level, 95 % CI: 0.68-0.96; P = 0.018). This association remained significant after adjustment for potential confounding factors including age, sex and BMI.. Our study suggested that higher serum 25OHD levels was associated with decreased risk of HT so that each 5 ng/ml increase in the serum 25OHD levels results in 19 % decrease in odds of HT.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Case-Control Studies; Cross-Sectional Studies; Female; Hashimoto Disease; Hospitals, Teaching; Humans; Iran; Male; Middle Aged; Outpatient Clinics, Hospital; Risk; Severity of Illness Index; Statistics as Topic; Thyroid Gland; Thyroid Hormones; Vitamin D Deficiency

In addition to its important metabolic activities, vitamin D also contributes to the regulation of the immune system. The aim of this study was to assess the relationship between hypovitaminosis D and disease activity in Moroccan children with juvenile idiopathic arthritis (JIA).. In this cross-sectional study, forty children with JIA were included, all having been diagnosed according to the classification criteria of International League of Associations for Rheumatology (ILAR). The children underwent anthropometric assessment and clinical evaluation. Disease activity was measured using the Disease Activity Score in 28 joints (DAS28) for polyarticular and oligoarticular JIA and the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for enthesitis-related arthritis. Serum 25-hydroxyvitamin [25(OH)D] D2 and D3 were measured using radioimmunoassay (RIA). Hypovitaminosis D was defined as serum 25(OH)D <30 ng/ml.. The average age of participants was 11 years ± 4.23. Hypovitaminosis D was observed in 75% of patients. In univariate analyses, 25(OH)D levels were negatively associated with DAS28 for polyarticular and oligoarticular JIA. No significant relationship was found between 25(OH)D levels and BASDAI for juvenile spondylarthropathy. In multivariate linear regression analysis, no association persisted between 25(OH)D levels and DAS28.. Our study suggested that serum levels of vitamin D were low in Moroccan children with JIA disease. Future studies with a larger population are needed to confirm our results.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Alkaline Phosphatase; Anthropometry; Antirheumatic Agents; Arthritis, Juvenile; Autoimmunity; Calcifediol; Calcium; Child; Comorbidity; Cross-Sectional Studies; Female; Humans; Male; Morocco; Phosphates; Socioeconomic Factors; Surveys and Questionnaires; Vitamin D Deficiency

Vitamin D has immunomodulatory properties, such as regulation of FOXP3 expression and regulatory T-cell activity. Our aim was to investigate whether plasma 25-hydroxyvitamin D [25(OH)D] concentrations associate with the development of β-cell autoimmunity and the transcriptional activity of FOXP3 or vitamin D3 convertase gene (CYP27B1) in CD4+ memory T cells.. We studied 83 Finnish and 32 Estonian children participating in the DIABIMMUNE and DIPP studies. Twenty-nine Finnish and six Estonian children tested positive for at least one diabetes-associated autoantibody. The plasma concentrations of 25(OH)D and 1,25(OH)₂D were analysed with an enzyme immunoassay. Gene expression of FOXP3 and CYP27B1 in the isolated CD4+ memory T cells was studied with reverse transcription quantitative polymerase chain reaction.. Vitamin D status did not differ between subjects positive and negative for β-cell autoantibodies. Finnish children had higher vitamin D status than Estonian children (p < 0.001). FOXP3 expression was higher in Estonian CD4+ memory T-cell samples than in Finnish samples (p < 0.01) even when including in both groups only children with serum 25(OH)D concentrations in the range of 50-80 nmol/L (p < 0.001).. These findings do not support a crucial role of circulating 25(OH)D as a regulator of β-cell autoimmunity or FOXP3 expression.

Topics: 25-Hydroxyvitamin D 2; 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Autoimmunity; Calcifediol; CD4-Positive T-Lymphocytes; Child; Child Nutritional Physiological Phenomena; Child, Preschool; Diabetes Mellitus, Type 1; Estonia; Female; Finland; Forkhead Transcription Factors; Gene Expression Regulation, Developmental; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Incidence; Insulin-Secreting Cells; Male; Nutritional Status; Vitamin D Deficiency

It has been suggested that vitamin D₂ is not very prevalent in the human food chain. However, data from a number of recent intervention studies suggest that the majority of subjects had measurable serum 25-hydroxyvitamin D₂ (25(OH)D₂) concentrations. Serum 25(OH)D₂, unlike 25(OH)D₃, is not directly influenced by exposure of skin to sun and thus has dietary origins; however, quantifying dietary vitamin D₂ is difficult due to the limitations of food composition data. Therefore, the present study aimed to characterise serum 25(OH)D₂ concentrations in the participants of the National Adult Nutrition Survey (NANS) in Ireland, and to use these serum concentrations to estimate the intake of vitamin D₂ using a mathematical modelling approach. Serum 25(OH)D₂ concentration was measured by a liquid chromatography-tandem MS method, and information on diet as well as subject characteristics was obtained from the NANS. Of these participants, 78.7 % (n 884) had serum 25(OH)D₂ concentrations above the limit of quantification, and the mean, maximum, 10th, 50th (median) and 90th percentile values of serum 25(OH)D₂ concentrations were 3.69, 27.6, 1.71, 2.96 and 6.36 nmol/l, respectively. To approximate the intake of vitamin D₂ from these serum 25(OH)D₂ concentrations, we used recently published data on the relationship between vitamin D intake and the responses of serum 25(OH)D concentrations. The projected 5th to 95th percentile intakes of vitamin D₂ for adults were in the range of 0.9-1.2 and 5-6 μg/d, respectively, and the median intake ranged from 1.7 to 2.3 μg/d. In conclusion, the present data demonstrate that 25(OH)D₂ concentrations are present in the sera of adults from this nationally representative sample. Vitamin D₂ may have an impact on nutritional adequacy at a population level and thus warrants further investigation.

Topics: 25-Hydroxyvitamin D 2; Adult; Agaricales; Cacao; Databases, Factual; Diet; Dietary Supplements; Ergocalciferols; Female; Food, Fortified; Functional Food; Humans; Ireland; Male; Models, Biological; Nutrition Surveys; Nutritional Status; Nutritive Value; Vitamin D Deficiency

The aim of the current study is to investigate the prevalence of hypovitaminosis D in Lebanese subjects, its robust predictors, evaluate the relationship between 25 hydroxy vitamin D [25(OH)D] and parathyroid hormone levels, and derive desirable vitamin D levels, based on a large hospital laboratory database spanning all age groups. Data from a large representative digitized database of 9147 subjects, mostly outpatients, evaluated between 2000-2004 and 2007-2008, in whom information on age, gender, service, and time of the year, was analyzed. The PTH-25(OH)D relationship was studied in a subset of 657 adult subjects, in whom such data were available. At a 25(OH)D cut-off of<20 ng/ml, the prevalence of hypovitaminosis D ranged between 58% and 62% in pediatric subjects, 44% and 60% in adults, and 41% and 62% in elderly, in the 2 study periods. At a cut-off <30 ng/ml, the prevalence was above 78%, in most sub-groups. Regardless of cut-off used, the only significant predictors of high mean 25(OH)D levels were the male gender in the pediatric group, and female gender in adults and elderly, summer/fall seasons, out-patient status, as well as study period. Curve fitting of the PTH-25(OH)D relationship, in adults and elderly, revealed a plateau at 25(OH)D levels of 17-21 ng/ml, depending on sub-study group. Hypovitaminosis D is prevalent in our sunny country, even using a conservative population-derived cut-off of 20 ng/ml, and thus the need for a public health strategy for supplementation.

Topics: 25-Hydroxyvitamin D 2; Academic Medical Centers; Adult; Aged; Calcifediol; Child; Climate; Cross-Sectional Studies; Dietary Supplements; Female; Health Promotion; Humans; Lebanon; Male; Nutrition Policy; Parathyroid Hormone; Practice Guidelines as Topic; Prevalence; Retrospective Studies; Risk Factors; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency has been implicated in the aetiology of infectious diseases and metabolic syndrome. These diseases are prevalent in the African and Asian-Indian populations of South Africa; however, there is limited data on 25-hydroxyvitamin D (25(OH)D) concentrations in these populations. The aim of the present study was to assess the vitamin D status and its predictors in healthy adults in Johannesburg. We assessed the vitamin D status of 730 adult African and Asian-Indian subjects residing in Johannesburg. The contributions of sun exposure, season, dietary intake of Ca and vitamin D, total body fat and body fat distribution to 25(OH)D concentrations were assessed. The concentrations of 25(OH)D were measured by HPLC. The contribution of 25(OH)D₃ to total 25(OH)D concentrations was assessed. The mean age of the subjects was 42·6 (SD 13·1) years (range: 18-65). Concentrations of 25(OH)D < 30 nmol/l were found in 28·6 % of the Asian-Indian subjects in comparison with 5·1 % of the African subjects (P< 0·0001). Parathyroid hormone (PTH) concentrations were negatively associated with 25(OH)D concentrations, while season and sun exposure were positive predictors explaining 16 % of the variance in 25(OH)D concentrations (P< 0·0001) in the African subjects. In the Asian-Indian subjects, PTH concentrations were negatively associated with 25(OH)D concentrations, while male sex, season and Ca supplementation were positive predictors and explained 17 % of the variance in 25(OH)D concentrations (P< 0·0001). In the multivariate regression analysis, neither total body fat nor body fat distribution was predictive of 25(OH)D concentrations in either group. In conclusion, factors such as sun exposure, dietary supplement use and ethnicity are important determinants of plasma 25(OH)D concentrations.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Calcifediol; Calcium, Dietary; Cohort Studies; Cross-Sectional Studies; Diet; Dietary Supplements; Female; Humans; India; Male; Prevalence; Seasons; Sex Characteristics; Skin; South Africa; Sunlight; Urban Health; Vitamin D; Vitamin D Deficiency

Poor vitamin D status can increase age-related muscle mass loss. However, existing prospective evidence is limited and controversial.. This study aimed to investigate the association of plasma 25-hydroxyvitamin D [25(OH)D] with muscle mass loss in middle-aged and elderly Chinese individuals over 6 years.. We conducted a prospective cohort study.. This community-based study included 568 men and women aged 50 to 70 years at baseline.. Baseline plasma concentrations of 25(OH)D and biomarkers of liver and kidney functions and inflammation were measured. Body composition was assessed at baseline and 6-year follow-up by dual-energy x-ray absorptiometry. Appendicular skeletal muscle mass (ASMM) and trunk lean mass were calculated and total body lean mass was defined as an overall measure of total nonfat and nonbone tissues.. Descriptive statistics and multiple linear regression were applied.. The 6-year loss of ASMM was 1.14 kg (5.3%) in men and 0.47 kg (3.1%) in women (all P values <0.001). Compared with the highest 25(OH)D tertile, participants in the lowest tertile had significantly more absolute loss of ASMM (-1.21 vs -1.00 kg; P for trend=0.024) after multivariate adjustments for conventional confounders, as well as protein intake. The association persisted after additional adjustment of bone mineral density and inflammatory markers (P for trend=0.017). No significant associations were detected between 25(OH)D and absolute loss of trunk lean mass or total body lean mass.. Lower 25(OH)D concentrations were prospectively associated with greater ASMM loss in middle-aged and elderly Chinese individuals independent of bone mineral density, inflammation, diet, and other risk factors.

Topics: 25-Hydroxyvitamin D 2; Aged; Aging; Biomarkers; Calcifediol; China; Cohort Studies; Female; Health Surveys; Humans; Longitudinal Studies; Male; Middle Aged; Muscle, Skeletal; Nutritional Status; Prospective Studies; Sarcopenia; Severity of Illness Index; Sex Characteristics; Vitamin D Deficiency

The aim was to study vitamin D status in a healthy adolescent Norwegian population at 69°N.. The data presented come from The Tromsø Study: Fit Futures, during the school year 2010/2011 (not including the summer months), where 1,038 (92% of those invited) participated. Physical examinations, questionnaires and blood samples were collected, and serum 25-hydroxyvitamin D (25(OH)D) were analyzed using LC-MS/MS.. RESULTS are presented from 475 boys and 415 girls (15-18 years old) with available blood samples. A total of 60.2% had vitamin D deficiency or insufficiency (serum 25(OH)D <50 nmol/l), 16.5% were deficient (<25 nmol/l) and 1.6% had severe vitamin D deficiency (<12.5 nmol/l). Only 12.4% had levels >75 nmol/l. A significant gender difference with a mean (SD) serum 25(OH)D level of 40.5 (20.5) nmol/l in boys and 54.2 (23.2) nmol/l in girls (p <0.01) was present. Furthermore, 51.3% of girls had levels >50 nmol/l in comparison to 29.7% of boys (p <0.01). There was an inverse correlation between parathyroid hormone levels and 25(OH)D, rs= -0.30 (p<0.01). Explanatory factors that were significantly associated with serum 25(OH)D levels in multivariate models were use of snuff, consumption of vitamin D fortified milk, cod liver oil and vitamin/mineral supplements, physical activity, sunbathing holiday and use of solarium in boys, and vitamin/mineral supplements, physical activity, sunbathing holiday and use of solarium in girls .. Vitamin D deficiency is prevalent during the school year among adolescents in northern Norway, particularly among boys.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Female; Humans; Life Style; Male; Norway; Risk Factors; Sex Distribution; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Calcitriol; Calcium; Female; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Humans; Middle Aged; Parathyroid Hormone; Phosphates; Vitamin D Deficiency; Vitamins

The aim of this study was to examine the possible association of vitamin D deficiency with diabetic retinopathy in 75 young Japanese type 1 diabetic patients. A multivariate regression analysis, duration of diabetes and vitamin D deficiency were independent determinants of diabetic retinopathy.

Topics: 25-Hydroxyvitamin D 2; Adult; Blood Glucose; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Incidence; Japan; Male; Risk Assessment; Risk Factors; Vitamin D Deficiency

Vitamin D is obtained from dietary sources and synthesized in the skin during exposure to ultraviolet B radiation in sunlight. During pregnancy, vitamin D is transported from mother to fetus through the placenta in the form of 25-hydroxyvitamin D [25(OH)D]. There is evidence that vitamin D influences neuronal differentiation, endocrine functions, and fetal brain growth. Animal studies indicate alterations in the offspring brain as a consequence of vitamin D deficiency during pregnancy. In humans, maternal vitamin D insufficiency has been linked to impaired child language development. Using data from a prebirth cohort with up to 22 years of follow-up, we examined the association of vitamin D status with proxies of offspring neurodevelopmental outcomes. During 1988-1989, pregnant women were recruited for the DaFO88 cohort (n = 965) in Aarhus, Denmark. Maternal concentrations of 25(OH)D were quantified in serum from week 30 of gestation via the LC-MS/MS method (n = 850). Offspring were followed up through national registries until the age of 22 years. We evaluated the association of the maternal concentration of 25(OH)D with offspring neurodevelopmental outcomes defined as first admission diagnosis or prescription of medication for (1) ADHD, (2) depression, and (3) scholastic achievement based on the mean grade on standardized written examinations in the 9th grade (final exams after 10 years of compulsory school in Denmark).. Maternal concentrations of 25(OH)D were higher compared to current levels (median 76 nmol/l; 5th to 95th percentiles 23-152). There was a direct association between maternal vitamin D status and offspring depression (p(trend) = 0.01); for ADHD there was no association. Scholastic achievement was slightly higher for offspring of mothers with a vitamin D status in the range of >50-125 nmol/l, but this nonlinear association was not statistically significant.. Our analyses based on biomarker measurement of 25(OH)D from a cohort of 850 pregnant women combined with long-term follow-up showed no support for a beneficial fetal programming effect of vitamin D status with regard to behavioral and affective disorders and scholastic achievement.

Topics: 25-Hydroxyvitamin D 2; Adult; Antidepressive Agents; Attention Deficit Disorder with Hyperactivity; Biomarkers; Calcifediol; Central Nervous System Stimulants; Cohort Studies; Denmark; Depression; Educational Status; Female; Follow-Up Studies; Humans; Infant, Newborn; Maternal Nutritional Physiological Phenomena; Neurogenesis; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Third; Prospective Studies; Registries; Risk; Vitamin D Deficiency

Studies of the associations of circulating total 25-hydroxyvitamin D (25(OH)D) with cardiovascular disease risk factors in adults have reported inconsistent findings. We aimed to compare prospective associations of two analogues of childhood 25(OH)D (25(OH)D2 and 25(OH)D3) with cardiovascular risk factors measured in adolescence.. We examined associations of childhood (ages 7-12 years) 25(OH)D2 and 25-25(OH)D3 with a range of cardiovascular risk factors (blood pressure, fasting lipids, glucose, insulin and C-reactive protein (CRP)) determined in adolescence (mean age 15.4 years). Data were from 2470 participants of the Avon Longitudinal Study of Parents and Children (ALSPAC), a prospective population-based cohort. After adjustments for age, gender, socioeconomic position and BMI, there were no associations of 25(OH)D2 with cardiovascular risk factors. There was a positive association of season-adjusted (and unadjusted) 25(OH)D3 with high-density lipoprotein cholesterol (HDL-C) (mean change per doubling of 25(OH)D3: 0.03 mmol/l; 95% confidence interval (CI): 0.001 to 0.05, p = 0.02) and an inverse association with fasting insulin (relative difference of -4.59% per doubling; 95% CI: -8.37 to -0.59, p = 0.03). Participants with total 25(OH)D concentration <50 nmol/l had 0.04 mmol/l lower HDL-C (95% CI: -0.07 to -0.01) and 5.54% higher fasting insulin (95% CI: 0.82 to 10.47) compared with participants with total 25(OH)D ≥72 nmol/l.. In the first prospective study of children/adolescents, we have shown that higher 25(OH)D3 concentrations in childhood are associated with higher levels of HDL-C and lower fasting insulin in adolescence.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Age Factors; Biomarkers; Calcifediol; Cardiovascular Diseases; Child; Cholesterol, HDL; England; Female; Humans; Insulin; Longitudinal Studies; Male; Prospective Studies; Risk Assessment; Risk Factors; Vitamin D Deficiency

The purpose of this study was to identify the prevalence and clinical consequences of vitamin D insufficiency in patients with takotsubo cardiomyopathy.. Takotsubo cardiomyopathy is a syndrome of acute, transient left ventricular dysfunction seen predominantly in postmenopausal women after acute emotional or physical stress. Postmenopausal women have a high prevalence of bone and musculoskeletal consequences related to hypovitaminosis D. Although rickets is known to cause a reversible dilated cardiomyopathy in children, the importance of vitamin D for adult cardiovascular health is less understood.. We prospectively identified patients diagnosed with takotsubo cardiomyopathy at Danbury Hospital from April 2009 through January 2011, collected demographic, clinical, laboratory, and angiographic data, and performed serum 25 hydroxyvitamin D levels during the index hospitalization. Vitamin D insufficiency was defined as serum 25-hydroxy-vitamin D less than 30 ng/mL. We compared parameters of myocardial damage and heart failure between patients with and without vitamin D insufficiency. A χ² test and a Student's t test were used for categorical and continuous variables, respectively. Statistical significance was set at P < .05 (2 tailed).. Twenty-seven women were diagnosed with takotsubo cardiomyopathy during the study period. The mean age was 67.4 years (SD 10.4). The serum 25-hydroxyvitamin D levels were performed on 25 patients, and 17 of these had hypovitaminosis D (68%). A comparison of laboratory and imaging parameters between the 2 groups revealed that patients with hypovitaminosis D had a slightly higher mean left ventricular end-diastolic pressure and lower mean left ventricular ejection fraction (P < .05), suggestive of slightly worse heart failure.. Women diagnosed with takotsubo cardiomyopathy have a high prevalence of vitamin D insufficiency. In our prospective study of 25 women with takotsubo cardiomyopathy, this was associated with worse hemodynamic parameters.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Cohort Studies; Connecticut; Electronic Health Records; Female; Heart; Heart Failure; Hospitals, Urban; Humans; Middle Aged; Postmenopause; Prevalence; Prospective Studies; Severity of Illness Index; Stroke Volume; Takotsubo Cardiomyopathy; Ventricular Dysfunction, Left; Vitamin D Deficiency

Links between vitamin D status and metabolic syndrome have been reported in cross-sectional studies; however, few prospective studies regarding this association exist. We performed this study to assess prospective association between vitamin D status and incident metabolic syndrome in a large population-based cohort.. This was a nested case-control study within the Tehran Lipid and Glucose Study (TLGS) which followed representative Tehranian adults. A total of 324 matched pairs aged 20 or older were selected. Cases and controls were free of metabolic syndrome according to definition of Joint Interim Statement (JIS) at baseline and followed for a mean duration of 6.8 years. Each case was matched individually by sex, age, duration of follow-up, and month of entry to the study with a randomly selected control. Prespecified cut points were used to characterize varying degrees of 25-hydroxyvitamin D [25(OH)D] deficiency (<20, 20-29.9, and ≥30 ng/mL). Conditional logistic regression was used to investigate the association between 25(OH)D concentration and the incident metabolic syndrome.. The mean age of participants was 40.8±11.7, and 50% were women. The median [interquartile range (IQR) 25-75] of serum 25(OH) D was 16 ng/mL (10-25 ng/mL) and there was no difference between cases (16 ng/mL; IQR 10-25 ng/mL) and controls (16 ng/mL; IQR 10-26 ng/mL). The odds ratio of serum 25(OH)D <20 ng/mL for developing metabolic syndrome was 0.97 [95% confidence interval (CI) 0.6-1.52] compared with serum 25(OH)D ≥30 ng/mL. Adjustment for potential confounders did not change the results.. Our study does not provide evidence that there is association between different serum vitamin D levels and incidence of metabolic syndrome.

Topics: 25-Hydroxyvitamin D 2; Adult; Blood Glucose; Calcifediol; Case-Control Studies; Cohort Studies; Cross-Sectional Studies; Female; Humans; Iran; Lipids; Male; Metabolic Syndrome; Middle Aged; Prospective Studies; Vitamin D Deficiency

Obesity is associated with lower serum concentrations of 25-hydroxyvitamin D (25OHD) and higher intact PTH. The threshold of 25OHD needed to maximally suppress intact PTH has been suggested as a marker of optimal vitamin D status.. In this study, we hypothesized that whereas the obese have a higher serum PTH and lower 25OHD, suppression of serum PTH by 25OHD would be independent of body weight.. We performed a retrospective analysis on 383 women (ages 24-75 y) with a wide range of body weights (43-185 kg) who were stabilized to 1-1.2 g calcium/d for 1 month before blood draw. Body composition, serum PTH, 25OHD, calcium, and creatinine were measured. Locally weighted regression and smoothing scatterplots were used to depict the association between serum PTH and 25OHD. A nonlinear exponential model determined the point for near maximal suppression of PTH by 25OHD.. The point for near maximal suppression of PTH by 25OHD for all women (body mass index, 31.4 ± 7.7 kg/m²) occurred at a 25OHD concentration of 21.7 ng/mL (95% confidence interval, 28-48 ng/mL). No point of maximal suppression was found for nonobese women, yet in the obese women (n = 207; body mass index, >30 kg/m²) suppression of PTH occurred at a 25OHD concentration of 11.1 ng/mL (95% confidence interval, 4.7-17.5 ng/mL).. These results suggest that if PTH is suppressed at a lower serum 25OHD in the obese compared to the entire population, the lower average 25OHD concentrations in the obese may not have the same physiological significance as in the general population.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Algorithms; Biomarkers; Body Mass Index; Calcifediol; Female; Humans; Middle Aged; Models, Biological; Nutritional Status; Obesity; Parathyroid Hormone; Retrospective Studies; Vitamin D Deficiency; Young Adult

Because vitamin D deficiency has been previously reported in patients with systemic lupus erythematosus (SLE), we decided to examine the prevalence of vitamin D deficiency in Thai SLE patients, to identify possible independent factors affecting serum 25-hydroxyvitamin D(2) and D(3) [25(OH)] vitamin D levels, and to examine the associations of serum 25(OH) vitamin D and disease activity and damage in Thai SLE patients.. A cross-sectional study was performed in 101 SLE patients. Blood samples were prospectively collected. The levels of 25(OH) vitamin D were measured by radioimmunoassay. The cutoffs for vitamin D deficiency and insufficiency were 30 and 20 ng/mL, respectively. Demographic, clinical, and laboratory data were collected, and their associations with 25(OH) vitamin D level were examined by univariate and multivariate linear regression analyses.. The level of 25(OH) vitamin D (mean [SD]) was 27.9 (7.6). Seventeen patients (17%) had vitamin D deficiency, 41 patients (41%) had vitamin D insufficiency, and 43 patients (42%) had normal vitamin D levels. Two thirds of the patients were taking relatively low-dose vitamin D supplementations. Current daily glucocorticoid dose and serum creatinine levels were negatively correlated with vitamin D levels (β = -0.207, P = 0.023; and β = -3.770, P = 0.003, respectively). There were no associations between disease activity or damage and 25(OH) vitamin D levels.. Vitamin D deficiency and insufficiency are common in SLE patients despite more than half of them taking vitamin D supplementations. Higher serum creatinine level and higher current daily glucocorticoid dose are associated with lower serum 25(OH) vitamin D levels. These patients may require higher doses of vitamin D supplementations.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Comorbidity; Creatinine; Cross-Sectional Studies; Dietary Supplements; Dose-Response Relationship, Drug; Female; Glucocorticoids; Humans; Lupus Erythematosus, Systemic; Male; Middle Aged; Prevalence; Prospective Studies; Regression Analysis; Thailand; Vitamin D; Vitamin D Deficiency

Recent studies in critically ill populations have suggested both adrenal insufficiency (AI) and vitamin D deficiency to be associated with worse clinical outcome. There are multiple mechanisms through which these pleiotropic hormones might synergistically influence critical illness.. The aim of the study was to investigate potential relationships between vitamin D status, adrenal status, and cardiovascular dysfunction in critically ill children.. We conducted a secondary analysis of data from a prospective cohort study.. The study was conducted on 319 children admitted to 6 Canadian tertiary-care pediatric intensive care units.. Vitamin D status was determined through total 25-hydroxyvitamin D (25OHD) levels. AI was defined as a cortisol increment under 9 μg/dL after low-dose cosyntropin. Clinically significant cardiovascular dysfunction was defined as catecholamine requirement during pediatric intensive care unit admission.. Using 3 different thresholds to define vitamin D deficiency, no association was found between vitamin D status and AI. Furthermore, linear regression failed to identify a relationship between 25OHD and baseline or post-cosyntropin cortisol. However, the association between AI and cardiovascular dysfunction was influenced by vitamin D status; compared to children with 25OHD above 30 nmol/L, AI in the vitamin D-deficient group was associated with significantly higher odds of catecholamine use (odds ratio, 5.29 vs 1.63; P = .046).. We did not find evidence of a direct association between vitamin D status and critical illness-related AI. However, our results do suggest that vitamin D deficiency exacerbates the effect of AI on cardiovascular stability in critically ill children.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adrenal Cortex; Adrenal Insufficiency; Calcifediol; Canada; Cardiovascular Diseases; Cardiovascular System; Catecholamines; Child; Child, Preschool; Cohort Studies; Cosyntropin; Hormones; Humans; Hydrocortisone; Infant; Intensive Care Units, Pediatric; Nutritional Status; Prospective Studies; Tertiary Care Centers; Vitamin D Deficiency

To determine the prevalence of vitamin D deficiency (VDD) in adult medical, non-tuberculous (non-TB) patients. To investigate associations with VDD. To compare the results with a similar study in TB patients at the same hospital.. Cross-sectional sample.. Central hospital in Malawi.. Adult non-TB patients (n = 157), inpatients and outpatients.. The primary outcome was the prevalence of VDD. Potentially causal associations sought included nutritional status, in/outpatient status, HIV status, anti-retroviral therapy (ART) and, by comparison with a previous study, a diagnosis of tuberculosis (TB).. Hypovitaminosis D (≤75 nmol/L) occurred in 47.8% (75/157) of patients, 16.6% (26/157) of whom had VDD (≤50 nmol/L). None had severe VDD (≤25 nmol/L). VDD was found in 22.8% (23/101) of in-patients and 5.4% (3/56) of out-patients. In univariable analysis in-patient status, ART use and low dietary vitamin D were significant predictors of VDD. VDD was less prevalent than in previously studied TB patients in the same hospital (68/161 = 42%). In multivariate analysis of the combined data set from both studies, having TB (OR 3.61, 95%CI 2.02-6.43) and being an in-patient (OR 2.70, 95%CI 1.46-5.01) were significant independent predictors of VDD.. About half of adult medical patients without TB have suboptimal vitamin D status, which is more common in in-patients. VDD is much more common in TB patients than non-TB patients, even when other variables are controlled for, suggesting that vitamin D deficiency is associated with TB.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Cross-Sectional Studies; Female; HIV Infections; Hospitals, General; Humans; Malawi; Male; Middle Aged; Prevalence; Risk Factors; Tuberculosis; Vitamin D Deficiency; Young Adult

To examine the nature of the association between 25-hydroxyvitamin D [25(OH)D] and newly diagnosed type 2 diabetes.. Serum 25(OH)D concentrations were measured for 761 participants (aged 20-83 years) in the Tehran Lipid and Glucose Study, selected for a 1-to-3 nested case-control study. Cases were 191 cases of Type 2 diabetes diagnosed during a median follow-up of 3.6 years. A total of 570 participants were matched with these cases with regard to age, sex, BMI, and month of entering the study. Diabetes was defined according to the American Diabetes Association criteria, 2003. Serum 25(OH)D was measured using the enzyme immunoassay method. Odds ratios for Type 2 diabetes were obtained from conditional logistic regression models for tertiles of serum 25(OH)D concentrations [tertile-1: 2.82-11.02 (reference), tertile-2: 11.03-21.80, and tertile-3: ≥ 21.82 ng/ml]. The multivariate model was adjusted for age, sex, family history of diabetes, systolic blood pressure, triglyceride-to- HDL cholesterol ratio, waist-to-height ratio, lifestyle modification intervention, leisure time physical activity, and fasting plasma glucose at baseline. Non-linearity in the associations between baseline 25(OH)D and Type 2 diabetes, was examined by using restricted cubic splines.. Unadjusted odds ratios (95% confidence intervals) of diabetes were 0.73 (0.74-1.13), 0.54 (0.34-0.85) for the second and third tertiles, respectively. Multivariate adjusted odds ratios were 0.47 (0.25-0.90) and 0.43 (0.23-0.82), respectively. Below the cutoff of ~ 10 ng/ml the risk of newly diagnosed Type 2 diabetes increased dramatically.. It was found that 25(OH)D concentrations contributed to the Type 2 diabetes incidence rate in a non-linear fashion, with the risk beginning to increase sharply for values < 10 ng/ml.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Calcifediol; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Follow-Up Studies; Humans; Immunoenzyme Techniques; Incidence; Iran; Logistic Models; Male; Middle Aged; Prospective Studies; Vitamin D Deficiency; Young Adult

Vitamin D deficiency is common in patients with chronic kidney disease (CKD). Current guidelines recommend treatment strategies in these patients similar to those for the general population, but the vitamin D nutritional status sufficient to prevent PTH levels from increasing in CKD is unknown. OBJECTIVE, MAIN OUTCOME MEASURE: Our aim was to study the relation between circulating PTH and 25(OH)D levels and to search for a 25(OH)D threshold associated with a significant PTH increase.. In the hospital-referred NephroTest cohort study, we measured 25(OH)D, PTH, and glomerular filtration rate (mGFR) by ⁵¹Cr-EDTA renal clearance in 929 adult patients with nondialysis CKD stages 1 to 5 and no vitamin D supplementation. Patients' mean age was 60.1 ± 14.7 years; 71% were men, and 9% were black. Their median mGFR was 37.8 mL/min/1.73 m².. We found a 25(OH)D threshold of 8 ng/mL with an upper limit of 20 ng/mL (95% confidence interval) by linear piecewise regression modeling of log-PTH for 25(OH)D adjusted for mGFR, age, race, and ionized calcium level. The smoothed curve confirmed that PTH concentration rose steeply when circulating 25(OH)D levels fell to less than 20 ng/mL.. Spontaneous 25(OH)D levels greater than 20 ng/mL seem sufficient to control serum PTH in CKD patients. This result reinforces guidelines to supplement vitamin D only if less than 30 ng/mL.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Calcium; Cohort Studies; Female; France; Glomerular Filtration Rate; Humans; Hypercalcemia; Male; Middle Aged; Parathyroid Hormone; Phosphates; Practice Guidelines as Topic; Prevalence; Prospective Studies; Renal Insufficiency, Chronic; Severity of Illness Index; Vitamin D Deficiency

A reverse J-shaped association between serum 25-hydroxyvitamin D (25[OH]D) concentration and all-cause mortality was suggested in a 9-year follow-up (1991-2000) analysis of the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994).. Our objective was to repeat the analyses with 6 years additional follow-up to evaluate whether the association persists through 15 years of follow-up.. The study included 15 099 participants aged ≥ 20 years with 3784 deaths.. Relative risk (RR) of death from all causes was adjusted for age, sex, race/ethnicity, and season using 2 Poisson regression approaches: traditional categorical and cubic splines. Results were given for 9 25(OH)D levels: <20, 20 to 29, 30 to 39, 40 to 49, 50 to 59, 60 to 74, 75 to 99 (reference), 100 to 119, and ≥ 120 nmol/L.. The reverse J-shaped association became stronger with longer follow-up and was not affected by excluding deaths within the first 3 years of follow-up. Similar results were found from both statistical approaches for levels <20 through 119 nmol/L. Adjusted RR (95% confidence interval [CI]) estimates for all levels <60 nmol/L were significantly >1 compared with the reference group. The nadir of risk was 81 nmol/L (95% CI, 73-90 nmol/L). For 25(OH)D ≥ 120 nmol/L, results (RR, 95% CI) were slightly different using traditional categorical (1.5, 1.02-2.3) and cubic splines approaches (1.2, 0.9-1.4). The association appeared in men, women, adults ages 20 to 64 years, and non-Hispanic whites but was weaker in older adults. The study was too small to evaluate the association in non-Hispanic black and Mexican-American adults.. A reverse J-shaped association between serum 25(OH)D and all-cause mortality appears to be real. It is uncertain whether the association is causal.

Topics: 25-Hydroxyvitamin D 2; Adult; Age Factors; Aged; Aged, 80 and over; Calcifediol; Cross-Sectional Studies; Female; Follow-Up Studies; Health Surveys; Humans; Male; Middle Aged; Mortality; Nutritional Status; Poisson Distribution; Sex Characteristics; United States; Vitamin D Deficiency; Young Adult

Topics: 25-Hydroxyvitamin D 2; Cost-Benefit Analysis; Dietary Supplements; Health Services Misuse; Humans; Mass Screening; Physician's Role; Physicians, Family; Vitamin D Deficiency; Vitamins

Topics: 25-Hydroxyvitamin D 2; Dietary Supplements; Humans; Mass Screening; Physician's Role; Vitamin D Deficiency

To estimate the association between serum 25-hydroxyvitamin D concentrations and maternal hyperglycaemia (post-load glucose concentration ≥ 7.5 mmol/l).. Pregnant women (n = 429; 61% black, 36% obese, 45% smokers) enrolled in a cohort study at <16 weeks gestation. Non-fasting blood samples were assayed for serum 25-hydroxyvitamin D at enrolment. At 24-28 weeks gestation, maternal hyperglycaemia was determined using a 50-g 1-h oral glucose challenge test.. A total of 67% of women had 25-hydroxyvitamin D concentrations < 50 nmol/l and 11% had maternal hyperglycaemia. Among smokers, each 23-nmol/l increase in serum 25-hydroxyvitamin D was associated with a reduction in the odds of maternal hyperglycaemia [odds ratio: 0.30 (95% CI: 0.13, 0.68)] after adjustment for parity, race/ethnicity, age, pre-pregnancy BMI, marital status, income, family history of diabetes, and gestational age of gestational diabetes mellitus screening. Among non-smokers, we found no association between early pregnancy vitamin D status and maternal hyperglycaemia.. Smoking status may modify the relationship between poor maternal vitamin D status and maternal hyperglycaemia.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Blood Glucose; Calcifediol; Cohort Studies; Female; Hospitals, University; Hospitals, Urban; Humans; Hyperglycemia; Maternal Nutritional Physiological Phenomena; Pennsylvania; Pregnancy; Pregnancy Complications; Pregnancy Trimester, First; Pregnancy Trimester, Second; Prevalence; Prospective Studies; Risk Factors; Smoking; Vitamin D Deficiency; Young Adult

We aimed to investigate the association between serum 25-hydroxyvitamin D (25(OH)D) and anthropometric indicators of adiposity among Korean preadolescent children aged 7-9 years.. Children aged 7 to 9 from the Ewha Birth & Growth Cohort were followed up from July to August 2011. Serum 25(OH)D concentration was measured using radio immunoassay. We assessed the magnitude of cross-sectional association with vitamin D concentrations and indicators of adiposity [body mass index (BMI), waist circumference (WC), mid-arm circumference (MAC), body fat mass (BFM), percent body fat (PBF), and triceps skinfold thickness (TSF)] using multiple linear and logistic regression analyses adjusted for sex, age, birth order, maternal education, and fruit/fruit juice intake.. Thirty-two (16%) out of a total of 205 children showed an optimal level of serum 25(OH)D, but most children did not reach a sufficient level (<30 ng/mL) even in summer. The level of 25(OH)D was inversely associated with BMI (β=-0.10, p<0.01), WC (β=-0.28, p<0.01), and BFM (β=-0.12, p=0.02) after adjusting for confounding factors and showed marginal boundary with PBF (β=-0.20, p=0.06) and TSF (β=-0.11, p=0.08). Regarding the risk of overweight, a 13% protective effect per 1 ng/mL increase of 25(OH)D was shown even after adjusting for relevant confounding factors (adjusted odds ratio=0.87, 95% confidence interval 0.78-0.98).. We found that the 25(OH)D concentrations were inversely associated with adiposity indices in preadolescent children. This study suggests that adequate vitamin D intake in growing children is crucial to maintain an optimal vitamin D level to prevent obesity and obesity-related health problems later in life.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Body Mass Index; Calcifediol; Child; Child Development; Cohort Studies; Confounding Factors, Epidemiologic; Cross-Sectional Studies; Female; Follow-Up Studies; Humans; Male; Obesity; Overweight; Republic of Korea; Risk; Vitamin D; Vitamin D Deficiency; Waist Circumference

Vitamin D deficiency and low bone mineral density (BMD) are complications of inflammatory bowel disease. Vitamin D deficiency is more prevalent among African Americans compared with whites. There are little data comparing differences in serum 25-hydroxyvitamin D (25OHD) concentrations and BMD between African American and white children with Crohn disease (CD).. We compared serum 25OHD concentrations of African American children with CD (n = 52) to white children with CD (n = 64) and healthy African American controls (n = 40). We also analyzed BMD using dual-energy x-ray absorptiometry results from our pediatric CD population.. African American children with CD had lower serum 25OHD concentrations (16.1 [95% confidence interval, CI 14.5-17.9] ng/mL) than whites with CD (22.3 [95% CI 20.2-24.6] ng/mL; P < 0.001). African Americans with CD and controls exhibited similar serum 25OHD concentration (16.1 [95% CI 14.5-17.9] vs 16.3 [95% CI 14.4-18.4] ng/mL; NS). African Americans with CD exhibited no difference in serum 25OHD concentration when controlling for seasonality, disease severity, and surgical history, although serum 25OHD concentration was significantly decreased in overweight children (body mass index ≥85%, P = 0.003). Multiple regression analysis demonstrated that obese African American girls with CD had the lowest serum 25OHD concentrations (9.6 [95% CI 6.8-13.5] ng/mL). BMD was comparable between African American and white children with CD (z score -0.4 ± 0.9 vs -0.7 ± 1.2; NS).. African American children with CD are more likely to have vitamin D deficiency compared with white children with CD, but have similar BMD. CD disease severity and history of surgery do not affect serum 25OHD concentrations among African American children with CD. African American children have low serum 25OHD concentrations, independent of CD, compared with white children. Future research should focus on how race affects vitamin D status and BMD in children with CD.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Black or African American; Body Mass Index; Bone Density; Bone Resorption; Calcifediol; Child; Cohort Studies; Crohn Disease; Cross-Sectional Studies; Female; Georgia; Humans; Male; Nutritional Status; Overweight; Prevalence; Prospective Studies; Severity of Illness Index; Vitamin D Deficiency; White People; Young Adult

Vitamin D deficiency is very common among HIV-infected subjects. We cross-sectionally evaluated the prevalence and risk factors for hypovitaminosis D in 91 HIV-infected Italian patients.. We studied in a cohort of 91 HIV-infected Italian patients the metabolism of Vitamin D by evaluating the in vitro expression of CYP27B1, CYP24A1 and vitamin D receptor (VDR) by monocytes and macrophages stimulated with the viral envelope protein gp120 or lipopolysaccharide (LPS).. The prevalence of vitamin D deficiency (25OHD < 10 ng/ml) and vitamin D insufficiency (25OHD 10-30 ng/ml) was 31% and 57%, respectively. In univariate analysis, female sex (p = 0.01), increasing age (p = 0.05), higher highly sensitive-C reactive protein (p = 0.025), higher parathyroid hormone (PTH) (p = 0.043) and lower BMI (p = 0.04) were associated with vitamin D deficiency. In multivariate analysis, the association was still significant only for PTH (p = 0.03) and female sex (p = 0.03). Monocyte stimulation with LPS (100 ng/ml) or gp120 (1 µg/ml) significantly upregulated CYP27B1 mRNA expression. Moreover, gp120 significantly increased VDR mRNA levels. On the contrary, neither LPS nor gp120 modified CYP24A1 levels. Macrophage stimulation with LPS (100 ng/ml) significantly upregulated CYP27B1 and CYP24A1 mRNA expression. When monocytes were cultured in the presence of 25OHD (40 ng/ml) and stimulated with LPS we detected significantly lower levels of 25OHD in the supernatant.. Vitamin D deficiency was very common in our cohort of HIV-infected patients. Chronic inflammation, including residual viral replication, may contribute to hypovitaminosis D, by modulating vitamin D metabolism and catabolism. Systematic screening may help identifying subjects requiring supplementation.

Topics: 25-Hydroxyvitamin D 2; 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Adult; Cells, Cultured; DNA Primers; Female; HIV Envelope Protein gp120; HIV Infections; Humans; Interleukin-6; Lipopolysaccharides; Macrophages; Male; Middle Aged; Monocytes; Multivariate Analysis; Real-Time Polymerase Chain Reaction; Steroid Hydroxylases; Vitamin D; Vitamin D Deficiency; Vitamin D3 24-Hydroxylase

Accumulating evidence has stipulated a strong correlation between vitamin D (vitD) deficiency and cardiovascular disease (CVD); however, a mechanistic link is missing. This study investigated the association of vitD with endothelial dysfunction parameters. Subjects comprised male patients with verified coronary artery disease (CAD) (n=69) and age- and sex-matched controls (n=20). 25-Hydroxyvitamin D [25(OH)D] was determined using high performance liquid chromatography with ultraviolet detection whereas asymmetric and symmetric dimethylarginine (ADMA and SDMA, respectively) were determined by liquid chromatography-mass spectrometry. Nitric oxide (NO) was determined spectrophotometrically and high-sensitivity C-reactive protein (hs-CRP) was determined using enzyme-linked immunosorbent assay (ELISA). Comparison of mean 25(OH)D concentrations of patients and controls yielded a significant result (p=0.0002). 25(OH)D2 was dominant in patients whereas 25(OH)D3 was dominant in controls (p=0.003 and 0.001, respectively). Comparison of mean ADMA and SDMA concentrations of patients exhibiting normal and suboptimal vitD yielded insignificant results (p=0.692 and 0.998, respectively). Significant results were obtained from the comparison of mean hs-CRP and NO concentrations of patients exhibiting normal and suboptimal vitD (p=0.035 and 0.031, respectively). Results suggest involvement of vitD with the NO system, however not via modulation of the dimethylated arginines. A potential anti-inflammatory activity for vitD is also raised.

Topics: 25-Hydroxyvitamin D 2; Adult; Arginine; C-Reactive Protein; Case-Control Studies; Coronary Artery Disease; Endothelium, Vascular; Humans; Male; Middle Aged; Nitric Oxide; Vitamin D; Vitamin D Deficiency

Since Pakistanis have high prevalence of hypovitaminosis-D as well as acute myocardial infarction (AMI), the objective of the study was to investigate the relationship between vitamin-D deficiency and risk of AMI in a hospital-based population and to identify major risk factors for this disease.. Fasting serum samples from 66 consecutive AMI patients [age 30-70 y] and 132 gender and age-matched (within 5 y) healthy controls were analyzed for concentrations of glucose, total-cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, calcium, inorganic phosphate, alkaline phosphatase (ALP), bone-ALP, parathyroid hormone (PTH), 25(OH) vitamin-D (25(OH)D) and alanine aminotransferase.. Mean concentrations of serum 25(OH)D, PTH, total-ALP, bone-ALP, LDL-cholesterol, HDL-cholesterol and glucose were significantly different compared to healthy controls (p<0.05). Percent vitamin-D deficiency/insufficiency (levels<30 ng/ml) was significantly greater in AMI patients compared to controls (93.9% vs.75.8%; p=0.001). Multiple conditional logistic regression analysis revealed that increased levels of 25(OH)D were associated with decreased risk of AMI [MAOR (95% CI)=0.821 (0.718, 0.940); p=0.004]. Hypertension and smoking were positively associated with AMI.. Increased vitamin-D levels were associated with decreased risk of AMI, while serum glucose, bone-ALP, hypertension and smoking were positively associated with it. Association of bone-ALP with AMI in hypovitaminosis-D is a novel finding of this study.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Alanine Transaminase; Alkaline Phosphatase; Bone and Bones; Calcium; Case-Control Studies; Cholesterol, HDL; Cholesterol, LDL; Female; Humans; Isoenzymes; Male; Middle Aged; Myocardial Infarction; Parathyroid Hormone; Risk Factors; Smoking; Triglycerides; Vitamin D Deficiency

In various populations, vitamin D deficiency is associated with chronic diseases and mortality. We examined the association between concentration of circulating 25-hydroxyvitamin D [25(OH)D], a marker of vitamin D status, and all-cause as well as cause-specific mortality.. The study included 3404 participants of the general adult Swiss population, who were recruited between November 1988 and June 1989 and followed-up until the end of 2008. Circulating 25(OH)D was measured by protein-bound assay. Cox proportional hazards regression was used to examine the association between 25(OH)D concentration and all-cause and cause-specific mortality adjusting for sex, age, season, diet, nationality, blood pressure, and smoking status. Per 10 ng/mL increase in 25(OH)D concentration, all-cause mortality decreased by 20% (HR = 0.83; 95% CI 0.74-0.92). 25(OH)D concentration was inversely associated with cardiovascular mortality in women (HR = 0.68, 95% CI 0.46-1.00 per 10 ng/mL increase), but not in men (HR = 0.97; 95% CI 0.77-1.23). In contrast, 25(OH)D concentration was inversely associated with cancer mortality in men (HR = 0.72, 95% CI 0.57-0.91 per 10 ng/mL increase), but not in women (HR = 1.14, 95% CI 0.93-1.39). Multivariate adjustment only slightly modified the 25(OH)D-mortality association.. 25(OH)D was similarly inversely related to all-cause mortality in men and women. However, we observed opposite effects in women and men with respect to cardiovascular and cancer mortality.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aging; Calcifediol; Cardiovascular Diseases; Cohort Studies; Female; Follow-Up Studies; Humans; Longitudinal Studies; Male; Middle Aged; Mortality; Neoplasms; Proportional Hazards Models; Risk Factors; Sex Characteristics; Switzerland; Vitamin D Deficiency

Several studies suggested that low serum concentrations of 25-hydroxyvitamin D (25(OH)D) are associated with an increased risk of cardiovascular disease (CVD). However, the evidence is still inconclusive, mostly based on CVD mortality and studies with single 25(OH)D measurements.. We aimed to assess the association of 25(OH)D with fatal and nonfatal CVD in the same study population, using repeated 25(OH)D measurements and competing risks analysis.. This was a population-based cohort study (ESTHER study, baseline 2000-2002). Follow-up data, including survival status, were collected after 2, 5, and 8 years. The response rate for survival was 99.9%.. Participants were recruited during a health screening examination by their general practitioners. 25(OH)D was measured in blood samples collected at baseline and the 5-year follow-up visit.. A total of 9949 men and women, aged 50 to 74 years at baseline, with sufficient knowledge of the German language and resident in the German state of Saarland were included in the study.. Outcomes included CVD, coronary heart disease (CHD), and stroke, in total and differentiated into fatal and nonfatal events.. Overall, 854 study participants had a nonfatal and 176 a fatal CVD event during 8 years of follow-up. Comparing subjects with 25(OH)D levels below 30 nmol/L and above 50 nmol/L resulted in a hazard ratio of 1.27 (95% confidence interval = 1.05-1.54) for total CVD and 1.62 (95% confidence interval = 1.07-2.48) for fatal CVD in a model adjusted for important potential confounders. No significant association for nonfatal CVD was observed. In dose-response analysis, we observed an increased cardiovascular risk at 25(OH)D levels below 75 nmol/L. Results for CHD and stroke were comparable to the results obtained for the composite outcome CVD.. Our results support evidence that low 25(OH)D levels are associated with moderately increased risk of CVD and indicate that the observed association is much stronger for fatal than for nonfatal events.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Cardiovascular Diseases; Cohort Studies; Coronary Disease; Female; Follow-Up Studies; Germany; Humans; Incidence; Male; Middle Aged; Models, Biological; Risk Assessment; Risk Factors; Severity of Illness Index; Stroke; Survival Analysis; Vitamin D Deficiency

To investigate if vitamin D deficiency is more prevalent in patients with Paget's disease of bone (PDB) than in age-matched controls.. We measured serum 25-OHD in 28 untreated patients with PDB and two control groups: 284 elderly men from an ongoing cohort from our department, and 151 postmenopausal women seen in our outpatient clinic for routine medical evaluation.. The mean ± SD serum 25-OHD was significantly lower in subjects with PDB (23.76 ± 6.29 ng/mL) than in the control groups of elderly men (27.86 ± 13.52 ng/mL) and postmenopausal women (30.30 ± 9.59 ng/mL), p = 0.015. The prevalence of vitamin D deficiency considering a cut-off point of serum 25-OHD < 30 ng/mL was 85.7% in patients with PDB, and in elderly men and postmenopausal women it was 66.7 % and 54.3%, respectively (p < 0.001).. These results suggest a high prevalence of hypovitaminosis D in patients with Paget's disease living in the tropics.

Topics: 25-Hydroxyvitamin D 2; Age Factors; Aged; Case-Control Studies; Female; Humans; Hyperparathyroidism, Secondary; Male; Middle Aged; Osteitis Deformans; Prevalence; Retrospective Studies; Vitamin D Deficiency

Maternal vitamin D deficiency has been suggested to influence fetal and neonatal health. Little is known about vitamin D status in Chinese pregnant women. The purpose of this study was to assess the vitamin D status of pregnant women residing in Beijing in winter and evaluate the impact of maternal factors on serum 25-hydroxyvitamin D [25(OH)D] levels. The study was conducted on 125 healthy pregnant women. For each individual, data concerning pre-pregnancy weight, educational status, use of multivitamins and behavioral factors such as daily duration of computer use, walking and sun exposure were obtained. Serum concentrations of 25(OH)D were measured by enzyme-linked immunosorbent assay. The prevalence of vitamin D deficiency (25(OH)D < 50 nmol/L) was 96.8% and almost half (44.8%) of women were severely vitamin D deficiency (25(OH)D < 25 nmol/L). The concentration of 25(OH)D was lower in women with shorter duration of sun exposure (≤ 0.5 h/day, 25.3 ± 8.9 nmol/L) than that in women with longer duration of sun exposure (> 0.5 h/day; 30.3 ± 9.5 nmol/L; P = 0.003). Thirty six women (28.8%) had sun exposure duration ≥ 1.5h/day. The 25(OH)D concentration in these women was 31.5 ± 9.4 nmol/L which was also much lower than the normal level. Women who reported taking a multivitamin supplement had significantly higher 25(OH)D concentrations (32.3 ± 9.5 nmol/L) when compared with non-users (24.9 ± 8.2 nmol/L; P < 0.001). Pregnant women in Beijing are at very high risk of vitamin D deficiency in winter. Duration of Sun exposure and the use of multivitamin were the most important determinants for vitamin D status. However, neither prolonging the time of sunlight exposure nor multivitamin supplements can effectively prevent pregnant women from vitamin D deficiency. Other measures might have to be taken for pregnant women to improve their vitamin D status in winter.

Topics: 25-Hydroxyvitamin D 2; Activities of Daily Living; Adult; China; Female; Humans; Pregnancy; Pregnancy Complications; Prevalence; Seasons; Socioeconomic Factors; Sunbathing; Vitamin D Deficiency

Patients with diabetes and vitamin-D insufficiency have increased insulin resistance. Similar observations among individuals with prediabetes are not well documented. The aim of this study was to find the occurrence of vitamin-D insufficiency/deficiency among individuals with prediabetes and to evaluate the relationship between vitamin-D status and insulin resistance.. One hundred fifty seven individuals with prediabetes who fulfilled all the inclusion and exclusion criteria underwent clinical examination, anthropometric measurements (waist circumference, waist-hip ratio, waist-height ratio) and blood sampling after overnight fast for estimation of fasting blood glucose, fasting insulin, 25(OH)vitamin-D, intact parathyroid hormone (iPTH) and lipid profile. One hour post 75 g glucose (1hPG) blood glucose during oral glucose tolerance test was measured.. Vitamin-D deficiency/insufficiency was found in 115 (73.25%) individuals with prediabetes. Severe vitamin-D deficiency (<10 ng/ml) was seen in 14.65 per cent individuals. Individuals with the lowest vitamin-D levels (<10 ng/ml) had the highest insulin resistance (HOMA2-IR: 2.04 ± 0.67). Serum 25(OH)D had a statistically significant inverse correlation with insulin resistance (HOMA2-IR; r=-0.33; P=0.008), and positive correlation with insulin sensitivity (QUICKI; r=0.39; P=0.002), after adjusting for BMI and HbA1c. There was no correlation between vitamin-D status and estimated beta cell mass (HOMA-β). The mean waist-height ratio among individuals with prediabetes was 0.57 (normal<0.5) indicating a high risk of cardiovascular morbidity. Individuals with elevated 1hPG>155 mg/dl had significantly higher BMI and worse insulin resistance, and 1hPG correlated well with 2 hour post glucose blood glucose (r=0.57; P<0.001). INTERPRETATIONS & CONCLUSIONS: Vitamin-D deficiency/insufficiency may have some role in the development/worsening of insulin resistance in individuals with prediabetes in our country who have a high cardiovascular risk. Prospective studies on a large group of individuals need to be done to confirm the findings.

Topics: 25-Hydroxyvitamin D 2; Adult; Blood Glucose; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Insulin Resistance; Lipids; Male; Middle Aged; Parathyroid Hormone; Prediabetic State; Risk Factors; Vitamin D; Vitamin D Deficiency

Vitamin D is known for maintaining Ca homeostasis and bone structure, and may also decrease susceptibility to chronic and infectious diseases. However, data on vitamin D status and its predictors among Southeast Asian populations are limited. We evaluated the distribution and determinants (genetic and environmental) of serum 25-hydroxyvitamin D (25(OH)D) concentrations among 504 middle-aged and elderly participants (aged 45-74 years) in the Singapore Chinese Health Study. Data on dietary and other lifestyle factors were collected by trained interviewers. Serum 25(OH)D concentrations and genetic polymorphisms in vitamin D metabolism pathway enzymes (cytochrome P450 (CYP) 2R1, 3A4, 27B1, 24A1; vitamin D binding protein (also known as group-specific component, GC); and vitamin D receptor) were measured using stored biospecimens. Mean 25(OH)D concentration was 68·8 nmol/l. Serum 25(OH)D concentrations were positively associated with dietary vitamin D intake, and inversely associated with hours spent sitting at work. BMI was not associated with 25(OH)D concentrations. CYP2R1 rs10741657, rs12794714, rs1993116; CYP3A4 rs2242480; and GC rs4588, rs7041, rs16847015, rs2298849 were statistically significantly associated with 25(OH)D concentrations. Individuals with the Gc2-2 haplotype (rs4588AA/rs7041TT) had statistically significantly lower 25(OH)D concentrations compared to all other Gc haplotypes (P-trend < 0·001). The majority of participants (86 %) had 25(OH)D concentrations ≥ 50 nmol/l, which is consistent with the 2011 Institute of Medicine (US) recommendation for bone health, and 32 % had concentrations of ≥ 75 nmol/l that are thought to be required for broader health effects. Dietary vitamin D intake, hours spent indoors at work and genetic variation in CYP2R1, CYP3A4 and GC are significant predictors of 25(OH)D concentrations among Singapore Chinese.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Cholestanetriol 26-Monooxygenase; Cohort Studies; Cross-Sectional Studies; Cytochrome P-450 CYP3A; Cytochrome P450 Family 2; Diet; Female; Gene-Environment Interaction; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Nutritional Status; Polymorphism, Single Nucleotide; Sedentary Behavior; Singapore; Vitamin D; Vitamin D Deficiency; Vitamin D-Binding Protein

Vitamin D status as measured by plasma 25-hydroxyvitamin D (25(OH)D) is important to human health. Circumpolar people rely on dietary sources and societal changes in the Arctic are having profound dietary effects. The objective of the present study was to determine plasma 25(OH)D status and factors important to plasma 25(OH)D in populations in Greenland. Inuit and non-Inuit aged 50-69 years in the capital in West Greenland (latitude 64°15'N) and in a major town and remote settlements in East Greenland (latitude 65°35'N) were surveyed. Supplement use and lifestyle factors were determined by questionnaires. Inuit food scores were computed from a FFQ of seven traditional Inuit and seven imported food items. 25(OH)D₂ and 25(OH)D₃ levels were measured in the plasma. We invited 1 % of the population of Greenland, and 95 % participated. 25(OH)D₃ contributed 99·7 % of total plasma 25(OH)D. Non-Inuit had the lowest median plasma 25(OH)D of 41 (25th-75th percentile 23-53) nmol/l compared with 64 (25th-75th percentile 51-81) nmol/l in Inuit (P< 0·001). Plasma 25(OH)D was below 20 and 50 nmol/l in 13·8 and 60·1 % of participants, respectively, with Inuit food item scores below 40 % (P< 0·001), and in 0·2 and 25·0 % of participants, respectively, with higher scores (P< 0·001). The Inuit diet was an important determinant of plasma 25(OH)D (P< 0·001) and its effect was modified by ethnicity (P= 0·005). Seal (P= 0·005) and whale (P= 0·015) were major contributors to plasma 25(OH)D. In conclusion, a decrease in the intake of the traditional Inuit diet was associated with a decrease in plasma 25(OH)D levels, which may be influenced by ethnicity. The risk of plasma 25(OH)D deficiency in Arctic populations rises with the dietary transition of societies in Greenland. Vitamin D intake and plasma 25(OH)D status should be monitored.

Topics: 25-Hydroxyvitamin D 2; Aged; Arctic Regions; Calcifediol; Diet; Diet Surveys; Dietary Supplements; Feeding Behavior; Female; Greenland; Humans; Inuit; Life Style; Male; Middle Aged; Nutritional Status; Surveys and Questionnaires; Vitamin D; Vitamin D Deficiency

The aim of the present research was to study the prevalence and severity of vitamin D deficiency in patients with diabetic foot infection. Patients were enrolled in two groups: diabetic patients with foot infection (n 125) as cases and diabetic patients without the infection as controls (n 164). Serum 25-hydroxyvitamin D (25(OH)D) was measured by RIA. Data were presented as means and standard deviations unless otherwise indicated and were analysed by SPSS. Results revealed that 25(OH)D (nmol/l) was significantly lower (40·25 (sd 38·35) v. 50·75 (sd 33·00); P < 0·001) in cases than in controls. Vitamin D inadequacy (25(OH)D < 75 nmol/l) was equally common in cases and controls (OR 1·45, 95 % CI 0·8, 3·0; P = 0·32), but cases had a greater risk of vitamin D deficiency (25(OH)D < 50 nmol/l) than controls (OR 1·8, 95 % CI 1·1, 3·0; P = 0·02). Risk of severe vitamin D deficiency (25(OH)D < 25 nmol/l) was significantly higher in cases than in controls (OR 4·0, 95 % CI 2·4, 6·9; P < 0·0001). Age, duration of diabetes and HbA1c were significantly higher in cases than in controls and therefore adjusted to nullify the effect of these variables, if any, on study outcome. The study concluded that vitamin D deficiency was more prevalent and severe in patients with diabetic foot infection. This study opens up the issue of recognising severe vitamin D deficiency (< 25 nmol/l) as a possible risk factor for diabetic foot infections and the need for vitamin D supplementation in such patients for a better clinical outcome. This could be substantiated by similar data from future studies.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Case-Control Studies; Diabetic Foot; Female; Hospitals, University; Humans; Immunity; India; Infections; Leukocytosis; Male; Middle Aged; Outpatient Clinics, Hospital; Prevalence; Risk Factors; Rural Health; Severity of Illness Index; Vitamin D Deficiency

The classical consequence of vitamin D deficiency is osteomalacia, but recent insights into the function of vitamin D suggest that it may play a role in other body systems as well. The objective of this study was to examine the association between 25-hydroxyvitamin D (25(OH)D) and markers of glucose metabolism (n = 593), global cognitive functioning (n = 116) and depression (n = 118) in European elderly participating in the SENECA study. Moreover, we wanted to explore whether the observed associations of 25(OH)D with depression and global cognitive performance were mediated by fasting plasma glucose (FPG) levels.. Cross-sectional associations between 25(OH)D and FPG, fasting plasma insulin (FPI) and homeostatic model assessment-insulin resistance (HOMA-IR), a marker of insulin resistance, were estimated from multiple regression analyses. Associations of 25(OH)D with global cognitive functioning (Mini Mental State Examination) and depression (Geriatric Depression Scale) were examined using Poisson regression.. An inverse association was observed between 25(OH)D and FPG (β-0.001), indicating a 1 % decrease in FPG per 10 nmol/L increase in 25(OH)D, but after full adjustment for demographic factors, lifestyle factors and calcium intake, this association was not statistically significant (P = 0.07). Although participants with intermediate and high serum 25(OH)D levels showed a tendency towards a lower depression score after adjustment for demographic and lifestyle factors, RR and 95 % CI: 0.73 (0.51-1.04) and 0.76 (0.52-1.11), respectively, these findings were not statistically significant.. An inverse association of 25(OH)D with depression and FPG was observed, but this association was not statistically significant. There was no association between 25(OH)D with FPI and HOMA-IR or with global cognitive functioning. More studies are needed to further explore the possible role of vitamin D in the various body systems.

Topics: 25-Hydroxyvitamin D 2; Aged; Aging; Biomarkers; Blood Glucose; Calcifediol; Cognition Disorders; Cohort Studies; Cross-Sectional Studies; Dementia; Depression; Europe; Female; Health Surveys; Humans; Hyperglycemia; Insulin; Insulin Resistance; Male; Vitamin D Deficiency

Decreased bone mineral density (BMD) was reported in HIV infected patients. Mechanisms leading to this decrease are poorly understood.. To assess factors relating to BMD in young HIV infected Israeli women of Ethiopian and Caucasian origin.. 75 young HIV infected women aged 34.5 ± 8.5 followed up at the Institute of Allergy, Clinical Immunology & AIDS filled a questionnaire about sun exposure, daily calcium intake and dress habits. Data about HIV status and treatment regimens were collected from the patients' charts. Serum hydroxyvitamin D [25(OH)D] levels, bone turnover markers and bone densitometry were evaluated.. 28 (65%) of Ethiopians and 2 (6.25%) of Caucasians had 25(OH)D serum levels <10 ng/ml (vitamin D deficiency), p = 0.001. 21 (67.7%) Ethiopians and 16 (39%) Caucasians avoided sun exposure, p = 0.019. Mean daily calcium intake was 491 ± 268.6 mg and 279 ± 252.6 mg, respectively, p = 0.001. Z scores < -1 found at Lumbar spine in 26 (89.7%), at Femoral neck in 20 (69%) at Total hip in 17 (58.6%) of vitamin D deficient patients compared to 20 (48.8%), 17 (41.5%), 9 (22%), in patients with 25(OH)D > 10 ng/ml, p < 0.01, <0.03, <0.001, respectively. Significantly more Ethiopian than Caucasian women covered their face (32.3% and 9.5%, p = 0.003) and hands (58.1% and 30.9%, p = 0.03). There was no difference in bone turnover markers levels.. Poorer vitamin D status was observed in Ethiopian women might be one of the important factors related to lower BMD in this group.

Topics: 25-Hydroxyvitamin D 2; Biomarkers; Bone and Bones; Bone Density; Bone Diseases, Metabolic; Calcifediol; Calcium, Dietary; Clothing; Diet; Ethiopia; Female; Follow-Up Studies; HIV Infections; Humans; Incidence; Israel; Middle Aged; Nutritional Status; Osteoporosis; Sunlight; Vitamin D Deficiency; White People

Sufficient vitamin D status may be defined as the evolutionary established circulating 25-hydroxyvitamin D [25(OH)D] matching our Paleolithic genome.. We studied serum 25(OH)D [defined as 25(OH)D₂ + 25(OH)D₃] and its determinants in 5 East African ethnical groups across the life cycle: Maasai (MA) and Hadzabe (HA) with traditional life styles and low fish intakes, and people from Same (SA; intermediate fish), Sengerema (SE; high fish), and Ukerewe (UK; high fish). Samples derived from non-pregnant adults (MA, HA, SE), pregnant women (MA, SA, SE), mother-infant couples at delivery (UK), infants at delivery and their lactating mothers at 3 days (MA, SA, SE), and lactating mothers at 3 months postpartum (SA, SE). Erythrocyte docosahexaenoic acid (RBC-DHA) was determined as a proxy for fish intake.. The mean ± SD 25(OH)D of non-pregnant adults and cord serum were 106.8 ± 28.4 and 79.9 ± 26.4 nmol/L, respectively. Pregnancy, delivery, ethnicity (which we used as a proxy for sunlight exposure), RBC-DHA, and age were the determinants of 25(OH)D. 25(OH)D increased slightly with age. RBC-DHA was positively related to 25(OH)D, notably 25(OH)D₂. Pregnant MA (147.7 vs. 118.3) and SE (141.9 vs. 89.0) had higher 25(OH)D than non-pregnant counterparts (MA, SE). Infant 25(OH)D at delivery in Ukerewe was about 65 % of maternal 25(OH)D.. Our ancient 25(OH)D amounted to about 115 nmol/L and sunlight exposure, rather than fish intake, was the principal determinant. The fetoplacental unit was exposed to high 25(OH)D, possibly by maternal vitamin D mobilization from adipose tissue, reduced insulin sensitivity, trapping by vitamin D-binding protein, diminished deactivation, or some combination.

Topics: 25-Hydroxyvitamin D 2; Adult; Animals; Biomarkers; Black People; Calcifediol; Diet; Environmental Exposure; Female; Fetal Blood; Humans; Infant, Newborn; Lactation; Life Style; Male; Maternal Nutritional Physiological Phenomena; Nutritional Status; Pregnancy; Pregnancy Complications; Sunlight; Tanzania; Vitamin D Deficiency

Previous national nutrition surveys in Irish adults did not include blood samples; thus, representative serum 25-hydroxyvitamin D (25(OH)D) data are lacking. In the present study, we characterised serum 25(OH)D concentrations in Irish adults from the recent National Adult Nutrition Survey, and determined the impact of vitamin D supplement use and season on serum 25(OH)D concentrations. Of the total representative sample (n 1500, aged 18+ years), blood samples were available for 1132 adults. Serum 25(OH)D was measured via immunoassay. Vitamin D-containing supplement use was assessed by questionnaire and food diary. Concentrations of serum 25(OH)D were compared by season and in supplement users and non-users. Year-round prevalence rates for serum 25(OH)D concentration < 30, < 40, < 50 and < 75 nmol/l were 6.7, 21.9, 40.1 and 75.6 %, respectively (11.1, 31.1, 55.0 and 84.0 % in winter, respectively). Supplement users had significantly higher serum 25(OH)D concentrations compared to non-users. However, 7.5 % of users had winter serum 25(OH)D < 30 nmol/l. Only 1.3 % had serum 25(OH)D concentrations >125 nmol/l. These first nationally representative serum 25(OH)D data for Irish adults show that while only 6.7 % had serum 25(OH)D < 30 nmol/l (vitamin D deficiency) throughout the year, 40.1 % had levels considered by the Institute of Medicine as being inadequate for bone health. These prevalence estimates were much higher during winter time. While vitamin D supplement use has benefits in terms of vitamin D status, at present rates of usage (17.5 % of Irish adults), it will have only very limited impact at a population level. Food-based strategies, including fortified foods, need to be explored.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Calcifediol; Cohort Studies; Cross-Sectional Studies; Diet; Dietary Supplements; Female; Humans; Ireland; Male; Middle Aged; Nutrition Surveys; Nutritional Status; Prevalence; Seasons; Vitamin D; Vitamin D Deficiency; Young Adult

The incidence of lymphoid malignancies has been increasing rapidly. Despite growing evidence for a relationship between serum 25-hydroxivitamin D [25(OH)D] concentrations and solid tumor risk, far less is known about the relationship between 25(OH)D and the risk of hematologic malignancy. This study aimed to assess the prognostic relevance of serum 25(OH)D concentrations in patients with B chronic lymphocytic leukemia (B-CLL) and non Hodgkin's lymphoma (NHL). The study was carried out on 195 newly diagnosed patients (75 B-CLL and 120 NHL) as well as 30 normal healthy controls. For all patients and normal controls serum 25(OH)D concentrations were assayed by enzyme-linked immunosorbent assay. Serum 25(OH)D levels were significantly lower in B-CLL and NHL patients as compared with normal controls (P = 0.00 for both). Also, there are significant associations between serum 25(OH)D levels and positive CD 38, positive ZAP 70 as well as Binet stages (χ(2) = 16.071, 16.644, 21.134 respectively; P = 0.00 for all) in the B-CLL patient group. Moreover, there are significant associations between serum 25(OH)D status and international prognostic index (IPI), performance status (χ(2) = 6.994, 9.212, P = 0.02, 0.01 respectively), but not with clinical stages (χ(2) = 3.115, P = 0.539) in NHL. Multivariate analysis revealed that 25(OH)D insufficiency is an independent poor prognostic factor in both B-CLL and NHL patient groups. In conclusion, 25(OH)D insufficiency is an independent poor prognostic factor in patients with B-CLL and NHL. 25(OH)D might be a therapeutic target in lymphoid malignancies.

Topics: 25-Hydroxyvitamin D 2; Aged; Biomarkers, Tumor; Case-Control Studies; Female; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Male; Middle Aged; Prognosis; Treatment Outcome; Vitamin D; Vitamin D Deficiency

Vitamin D is an important regulator of bone health. Previous studies examining the association between vitamin D deficiency and osteoporotic fractures have reported conflicting results. The relationship between vitamin D status and risk of vertebral fractures in diabetic patients is unknown. The objective of this study was to examine whether low serum 25-hydroxyvitamin D [25(OH)D] levels were associated with vertebral fractures in patients with type 2 diabetes. This cross-sectional study was conducted among 161 postmenopausal women and 180 men with type 2 diabetes. Serum concentrations of 25(OH)D were measured and the presence of vertebral fracture was assessed using lateral plain radiographs of the thoracolumbar spine. Women had lower 25(OH)D levels than men (31.3 ± 17.7 vs. 41.3 ± 26.5 ng/mL, p<0.001). Vertebral fractures were found in 16% of patients. Men with a serum 25(OH)D concentration greater than 30 ng/mL showed a lower prevalence of vertebral fractures compared to those with 20-29.9 ng/mL or those with less than 20 ng/mL (9.4% vs. 17.9% vs. 21.7%, p for trend=0.036). However, there was no significant association between vitamin D status and the prevalence of vertebral fractures in women (14.4% vs. 19.2% vs. 26.6%, p for trend=0.111). After adjusting for multiple confounding factors, men with a serum 25(OH)D concentration of less than 20 ng/mL were associated with an increased risk of vertebral fractures (OR 7.87; 95% CI 1.69-36.71), but not women. In conclusion, serum 25(OH)D levels below 20 ng/mL were associated with an increased vertebral fracture risk in men with type 2 diabetes.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Calcifediol; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Nutritional Status; Osteoporotic Fractures; Prevalence; Radiography; Recurrence; Republic of Korea; Risk Factors; Severity of Illness Index; Sex Factors; Spinal Fractures; Vitamin D Deficiency

The aims of the present study were to determine compliance with current advice on vitamin D and to assess the influence of season, dietary intake, supplement use and deprivation on vitamin D status in pregnant mothers and newborns in the north of Scotland where sunlight exposure is low. Pregnant women (n 1205) and their singleton newborns were studied in the Aberdeen Maternity Hospital (latitude 57°N) between 2000 and 2006. Plasma 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 were measured at 19 weeks of gestation in mothers and at delivery in newborns. During pregnancy, 21·0 (95 % CI 18·5, 23·5) % of women took vitamin D supplements. The median intake was 5 μg/d and only 0·6 (95 % CI 0·1, 1·0) % took the recommended 10 μg/d. Supplement use, adjusted for season, dietary intake and deprivation, significantly increased maternal 25-hydroxyvitamin D (25(OH)D) by 10·5 (95 % CI 5·7, 15·2) nmol/l (P< 0·001); however, there was no significant effect on cord 25(OH)D (1·4 (95 % CI - 1·8, 4·5) nmol/l). The biggest influence on both maternal and cord 25(OH)D was season of birth (P< 0·001). Compared with the least deprived women (top three deciles), the most deprived pregnancies (bottom three deciles) were characterised by a significantly lower seasonally adjusted 25(OH)D ( - 11·6 (95 % CI - 7·5, - 15·7) nmol/l in the mother and - 5·8 (95 % CI - 2·3, - 9·4) nmol/l in the cord), and a lower level of supplement use (10 (95 % CI 4, 17) v. 23 (95 % CI 20, 26) %). More should be done to promote vitamin D supplement use in pregnancy but the critical importance of endogenous vitamin D synthesis, and known adaptations of fat metabolism specific to pregnancy, suggest that safe sun advice may be a useful additional strategy, even at high latitude.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Dietary Supplements; Female; Fetal Blood; Gestational Age; Humans; Infant, Newborn; Nutritional Status; Pregnancy; Pregnancy Complications; Scotland; Seasons; Sunlight; Vitamin D; Vitamin D Deficiency

Vitamin D deficiency {defined by the blood concentration of 25-hydroxyvitamin D [25(OH)D]} has been associated with many adverse health outcomes. Genetic and nongenetic factors account for variation in 25(OH)D, but the role of interactions between these factors is unknown. To assess this, we examined 1204 women of European descent from the Carotenoids in Age-Related Eye Disease Study, an ancillary study of the Women's Health Initiative Observational Study. Twenty-nine single nucleotide polymorphisms (SNPs) in 4 genes, GC, CYP2R1, DHCR7, and CYP24A1, from recent meta-analyses of 25(OH)D genome-wide association studies were genotyped. Associations between these SNPs and 25(OH)D were tested using generalized linear regression under an additive genetic model adjusted for age, blood draw month, and ancestry. Results were stratified by season of blood draw and, separately, vitamin D intake for the 6 SNPs showing a significant association with 25(OH)D at the P < 0.01 level. Two nonsynonymous SNPs in GC and 4 SNPs in CYP2R1 were strongly associated with 25(OH)D in individuals whose blood was drawn in summer (P ≤ 0.002) but not winter months and, independently, in individuals with vitamin D intakes ≥400 (P ≤ 0.004) but not <400 IU/d (10 μg/d). This effect modification, if confirmed, has important implications for the design of genetic studies for all health outcomes and for public health recommendations and clinical practice guidelines regarding the achievement of adequate vitamin D status.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Cholestanetriol 26-Monooxygenase; Cohort Studies; Cytochrome P450 Family 2; Female; Genetic Association Studies; Humans; Middle Aged; Polymorphism, Single Nucleotide; Postmenopause; Prospective Studies; Retrospective Studies; Seasons; Sunlight; United States; Vitamin D; Vitamin D Deficiency; Vitamin D-Binding Protein; White People

The 2007 to 2009 Canadian Health Measures Survey reported vitamin D status in a representative sample of Canadians (6-79 y); however, children <6 y were not assessed. Our objective was to measure vitamin D intake from food and supplements, sun exposure, and biological vitamin D status of children ages 2 through 5 y in Montréal (latitude 45°N). Preschoolers (n = 508) were recruited between June 2010 and 2011 in a random sample of licensed daycares in the regions of greater Montréal, Canada in a cross-sectional study. The total plasma 25-hydroxyvitamin D [25(OH)D] concentration was measured using a chemiluminescence assay (Liaison, Diasorin). Dietary intake was assessed during one 24-h period plus a 30-d FFQ. Socioeconomic, demographic, anthropometry, and sun exposure data were collected. Plasma 25(OH)D was ≥50 nmol/L in 88% of children, whereas 49.4% had concentrations ≥75 nmol/L during the 1-y study. Almost 95% of preschoolers had vitamin D intakes less than the Estimated Average Requirement (EAR), and 4.8% of preschoolers ≤3.9 y and 25.9% of preschoolers ≥4 y had calcium intakes less than the EAR. Plasma 25(OH)D was different across age, income, sun index, milk intake, and dietary and supplemental vitamin D intake tertiles. Despite vitamin D intakes less than the EAR, the vitamin D status of Montréal preschoolers attending daycare is mostly satisfactory even in winter, suggesting that the EAR value is too high in the context of typical exogenous intakes of vitamin D in North America.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Calcium; Calcium, Dietary; Child Day Care Centers; Child, Preschool; Cross-Sectional Studies; Diet; Dietary Supplements; Female; Humans; Male; Nutrition Surveys; Nutritional Status; Prevalence; Quebec; Seasons; Skin; Sunlight; Vitamin D; Vitamin D Deficiency

Hypovitaminosis D is an international problem; however, there is little information about its prevalence in apparently healthy Indian children living at high altitudes.. To determine (i) the prevalence of hypovitaminosis D and (ii) the association of serum vitamin D with the risk factors for diabetes among Indian Koya children.. A cross-sectional study of 290 (129 males) school children aged 10.7 ± 2.9 yr was performed. Anthropometric measures, blood pressure (BP), Tanner stages and serum levels of glucose, lipids, and insulin were measured. 25-hydroxyvitamin D [25(OH)D] was measured by radioimmunoassay (Dia Sorin).. The prevalence of obesity was 3.4% (10), overweight 3.4% (10), normal weight 79.0% (229), and underweight 14.1 % (41) per CDC reference standards. Concentrations of [25(OH)D] were median 10 (range 8-13 ng/mL); 10 (3.4%) had insufficient vitamin D levels (20 to <30 ng/mL), 136 (46.9%) had deficient levels (10 to <20 ng/mL), 144 (49.7%) had severe deficiency (<10 ng/mL) and none had optimal levels (≥30 ng/mL). There was an inverse significant correlation between [25(OH)D] and age (r = 0.14), body mass index (BMI) (r = 0.16), waist circumference (r = 0.15), systolic BP (r = 0.19), hemoglobin (r = 0.19), glucose (r = 0.22), insulin (r = 0.13), and homeostasis model of assessment-insulin resistance (r = 0.16). Multiple linear regression analysis showed that 25(OH)D concentrations were significantly and inversely associated with glucose concentrations (β = -0.28; p = 0.02) adjusted for age, BMI, systolic BP, hemoglobin, and insulin.. This study demonstrated a high prevalence of both 25(OH)D deficiency and insufficiency and an inverse association between 25(OH)D and glucose concentration in apparently healthy Koya Indian children. Further research is needed to confirm these findings.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Age Factors; Altitude; Argentina; Calcifediol; Child; Child, Preschool; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Humans; Indians, South American; Insulin Resistance; Male; Prevalence; Risk Factors; Severity of Illness Index; Vitamin D; Vitamin D Deficiency; Young Adult

Higher serum total 25-hydroxyvitamin D (25(OH)D) concentrations have been associated with better lung function and lower risk of allergic disease. 25(OH)D3 constitutes the majority of total 25(OH)D and has been suggested to be more potent than 25(OH)D2. We studied the prospective associations of 25(OH)D2 and 25(OH)D3 with asthma, wheezing, flexural dermatitis, and lung function in children who participated in the Avon Longitudinal Study of Parents and Children-a population-based contemporary birth cohort of children born in 1991-1992 from South West England.. Serum 25(OH)D2 and 25(OH)D3 concentrations, measured at a mean age of 9.8 years, were related to incident cases of wheezing (study sample: n = 3,323, 141 cases; 4%), asthma (n = 3,323, 464 cases; 14%), and flexural dermatitis (n = 3,748, 300 cases; 8%), as well as lung function (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], and mid-forced expiratory flow assessed at a mean age of 15.5 years: n = 2,259).. 25(OH)D2 was inversely associated with flexural dermatitis (adjusted odds ratio per doubling of exposure = 0.83 [95% confidence interval = 0.72-0.94]) and wheezing (0.83 [0.68-1.00]), and 25(OH)D3 was positively associated with flexural dermatitis (1.09 [1.00-1.18]) and wheezing (1.14 [1.03-1.28]). 25(OH)D2 was weakly positively associated with FEV1, and FVC. 25(OH)D3 was not associated with lung function.. These results suggest that higher 25(OH)D3 concentrations are associated with increased risk of wheezing and flexural dermatitis. Despite being one of the few prospective studies and being able to adjust for confounders, these findings need replication. Our results do not provide strong evidence that lower concentrations of vitamin D are detrimental to respiratory and allergic health in children.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Asthma; Calcifediol; Child; Cohort Studies; Dermatitis; England; Female; Humans; Incidence; Longitudinal Studies; Male; Prospective Studies; Regression Analysis; Respiratory Function Tests; Respiratory Sounds; Vitamin D Deficiency

The relationship between vitamin D and common mental disorders (CMDs) remains unclear. We aimed to determine if behaviours affecting vitamin D concentrations differ between individuals with or without CMDs and evaluate, cross-sectionally and prospectively, the extent to which the association between 25(OH)D and CMDs are explained by these behaviours.. Data are from the 1958 British birth cohort (n = 7401). Behaviours were ascertained by questionnaire at age 45 years. CMDs (depression, anxiety, panic, phobia) were assessed using the Clinical Interview Schedule-Revised at 45 years and depression using Mental Health Inventory-5 at 50 years.. Participants with CMDs at 45 years differed from others on some but not all vitamin D related behaviours. There were inverse, cross-sectional associations at 45 years of 25(OH)D with depression and panic, which persisted after adjustment for vitamin D related behaviours (OR = 0.57, 95% CI: 0.40,0.81 and OR = 0.33, 95% CI: 0.40,0.81, respectively). Association between 25(OH)D and subsequent (50 years) risk of depression was non-linear (p = 0.01), with lower risk for participants with 25(OH)D between 50 and 85 nmol/l compared with those with lower or higher concentrations.. This study provides support for an association of low 25(OH)D concentrations with current and subsequent risk of depression in mid-adulthood.

Topics: 25-Hydroxyvitamin D 2; Anxiety Disorders; Calcifediol; Cohort Studies; Cross-Sectional Studies; Depressive Disorder; Diet; Dietary Supplements; Female; Health Surveys; Humans; Longitudinal Studies; Male; Middle Aged; Panic Disorder; Phobic Disorders; Prevalence; Prospective Studies; Sex Factors; United Kingdom; Vitamin D; Vitamin D Deficiency

Secondary hyperparathyroidism (SHPT) is one of the outcomes of vitamin D deficiency that negatively affects bone metabolism. We studied the ethnic differences in vitamin D status in Finland and its effect on serum intact parathyroid hormone (S-iPTH) concentration and bone traits. The study was done in the Helsinki area (60°N) during January-February 2008. A total of 143 healthy women (20-48 years of age) from two groups of immigrant women (Bangladeshi, n 34 and Somali, n 48), and a group of ethnic Finnish women (n 61) were studied in a cross-sectional setting. Serum concentrations of 25-hydroxyvitamin D (S-25OHD) and S-iPTH were measured. Peripheral quantitative computed tomography measurements were taken at 4 and 66 % of the forearm length. In all groups, the distribution of S-25OHD was shifted towards the lower limit of the normal range. A high prevalence of vitamin D insufficiency (S-25OHD < 50 nmol/l) was observed (89·6 %) in the Somali group. The prevalence of SHPT (S-iPTH>65 ng/l) was higher (79·1 %) in Somali women than in Finnish women (16 %). There was a significant association between S-25OHD and S-iPTH (r - 0·49, P < 0·001). Ethnicity and S-25OHD together explained 30 % of the variation in S-iPTH. The total bone mass at all sites of the forearm, fracture load and stress-strain index was higher (P < 0·001) in Bangladeshi and Finnish women than in Somali women. The high prevalence of hypovitaminosis D, SHPT and low bone status in Somali women indicates a higher risk of osteoporosis.

Topics: 25-Hydroxyvitamin D 2; Adult; Bangladesh; Bone Density; Calcifediol; Cross-Sectional Studies; Emigrants and Immigrants; Female; Finland; Forearm; Humans; Hyperparathyroidism, Secondary; Middle Aged; Parathyroid Hormone; Premenopause; Prevalence; Seasons; Severity of Illness Index; Somalia; Urban Health; Vitamin D Deficiency; Young Adult

Low 25-hydroxyvitamin D levels have been associated with a higher risk of developing multiple sclerosis and increased relapse rates in patients with multiple sclerosis. As a sterol hormone involved in multiple immunologic pathways, vitamin D may play a role in preventing monophasic immune-mediated central nervous system attacks from developing into recurrent disease.. To investigate the association between low serum vitamin D levels and recurrent spinal cord disease.. We performed a retrospective analysis at Johns Hopkins Transverse Myelitis Center, Baltimore, Maryland, evaluating 25-hydroxyvitamin D levels in 77 patients with monophasic and recurrent inflammatory diseases of the spinal cord.. Levels of 25-hydroxyvitamin D.. Vitamin D levels are significantly lower in patients who developed recurrent spinal cord disease, adjusting for season, age, sex, and race.. This study provides a basis for a prospective trial of measuring 25-hydroxyvitamin D levels in these patient populations and assessing the influence of vitamin D supplementation on the frequency of relapses in those with recurrent inflammatory spinal cord disease.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Aging; Calcifediol; Child; Child, Preschool; Female; Humans; Immunoglobulin G; Infant; Male; Middle Aged; Mobility Limitation; Myelitis; Myelitis, Transverse; Neuromyelitis Optica; Recurrence; Retrospective Studies; Seasons; Vitamin D; Vitamin D Deficiency; Young Adult

Low vitamin D status is highly prevalent worldwide, and the major determinants are sun exposure and vitamin D intake. We aimed to measure vitamin D status in a sample of overweight/obese adults in Puerto Rico, an area with plenty of sun exposure, and relate it to vitamin D intake, sun exposure and body composition.. Serum 25(OH)D levels (liquid chromatography-tandem mass spectrometry), body weight and fat (bioimpedance), vitamin D intake and sun exposure (questionnaires) were assessed. Analysis included age-adjusted correlations and multivariate regression.. In 98 subjects (66% females; 40-65 years), median serum 25(OH)D levels were 30.7 ng/ml (25-75th percentile 25.0-37.3); 55% had levels >30 ng/ml, 31% had levels between 20 and 30 ng/ml and 14% had levels <20 ng/ml. Total vitamin D intake was 180 IU/day (45-615), and the sun exposure score was 22 (17-27). After adjusting for gender, 25(OH)D levels were significantly correlated with vitamin D intake (r = 0.24, p = 0.018), the sum of sun exposure and vitamin D intake indices (r = 0.34, p = 0.001) and percent body fat (r = -0.25, p = 0.01). After adjusting for age, gender and percent body fat, the sum of sun exposure and vitamin D intake indices remained statistically associated with 25(OH)D levels (β = 1.5, p < 0.01).. In this group of overweight and obese individuals, 25(OH)D was significantly related to vitamin D intake, sun exposure and vitamin D intake indices and percent body fat.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Anthropometry; Body Composition; Calcifediol; Cross-Sectional Studies; Environmental Exposure; Female; Humans; Male; Middle Aged; Motor Activity; Obesity; Overweight; Puerto Rico; Risk Factors; Skin Pigmentation; Sunlight; Urban Population; Vitamin D Deficiency

The performance of recently developed vitamin D total assays (ADVIA Centaur and Elecsys) was compared to that of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and LIASON 25-OH Vitamin D total assays.. A total of 157 clinical samples and standard reference material (SRM) 972 were analyzed.. The correlations of LC-MS/MS with the three immunoassays were acceptable. However, compared to LC-MS/MS, LIAISON and ADVIA Centaur showed negative bias, and Elecsys showed positive bias. There was a lack of agreement among the four methods with only LC-MS/MS results close to the certified values of SRM 972. The prevalence of vitamin D insufficiency (<50 nmol/L) was higher with ADVIA Centaur (51.6%) and LIAISON (52.2%) and lower with Elecsys (37.6%), compared with that of LC-MS/MS (44.6%).. The new, automated total vitamin D assays show acceptable correlation with LC-MS/MS, and could be used in routine laboratories. However, standardization of vitamin D assays and consideration of assay-specific decision limits should be addressed.

Topics: 25-Hydroxyvitamin D 2; Automation, Laboratory; Calcifediol; Chromatography, High Pressure Liquid; Cross Reactions; Humans; Immunoassay; Luminescent Measurements; Prevalence; Reproducibility of Results; Republic of Korea; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Vitamin D Deficiency

Obstructive sleep apnea (OSA) and 25-hydroxyvitamin-D₃ (25-OH-D) deficiency are two separate disorders associating with obesity, inflammation, and impaired glucose metabolism. We aimed to investigate the vitamin D status of OSA patients regarding to potential links between lower vitamin D levels and abnormal glucose metabolism, which is one of the main adverse outcomes of OSA. Study group is composed of 190 non-diabetic subjects who were suspected of having OSA. Subjects undergone polysomnography and were grouped due to apnea-hypopnea indices (AHI) as controls (AHI < 5, n = 47), mild OSA (5 ≤ AHI < 15, n = 46), moderate OSA (15 ≤ AHI < 30, n = 47), and severe OSA (AHI ≥ 30, n = 50). Serum 25-OH-D, HbA₁c, insulin levels were measured and 75-g oral glucose tolerance test was performed. Serum 25-OH-D level (ng/ml) of OSA patients were lower than control subjects (17.4 ± 6.9 vs. 19.9 ± 7.8), and decrement was parallel to severity of OSA; as 18.2 ± 6.4 (5 ≤ AHI < 15), 17.5 ± 7.4 (15 ≤ AHI < 30), and 16.3 ± 6.9 (AHI > 30), respectively (P = 0.097, r = -0.13). However, severe female OSA patients had significantly lower 25-OH-D levels (11.55 ng/ml), while control males had the highest mean value (21.7 ng/ml) (P < 0.001). Frequency of insulin resistance (IR) was 48%, prediabetes 41%, diabetes 16% in OSA patients. Mean 25-OH-D level of insulin resistant subjects (HOMA-IR ≥ 2.7, n = 77, AHI = 35.5) was lower than non-insulin resistant subjects (HOMA-IR < 2.7, n = 113, AHI = 19.8) as 16.18 ± 7.81 versus 19.2 ± 6.6, respectively (P = 0.004). 25-OH-D level of 91 non-diabetic subjects (n = 91, AHI = 19.7) was 19.5 ± 7.4, prediabetics (n = 75, AHI = 28.7) was 17.45 ± 6.9, and diabetics (n = 24, AHI = 46.3) was 13.8 ± 5.3 (P = 0.02). We showed that subjects with more severe OSA indices (AHI ≥ 15) tended to present lower vitamin D levels correlated to increased prevalence of IR, prediabetes, and diabetes. Vitamin D deficiency may play a role and/or worsen OSA's adverse outcomes on glucose metabolism. OSA patients may be considered for supplementation treatment which was shown to ameliorate abnormal glucose metabolism and inflammation.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Glucose Metabolism Disorders; Glycated Hemoglobin; Humans; Insulin; Insulin Resistance; Male; Middle Aged; Prediabetic State; Prevalence; Severity of Illness Index; Sex Characteristics; Sleep Apnea, Obstructive; Turkey; Vitamin D Deficiency

Cutaneous synthesis of vitamin D by exposure to UVB is the principal source of vitamin D in the human body. Our current clothing habits and reduced time spent outdoors put us at risk of many insufficiency-related diseases that are associated with calcaemic and non-calcaemic functions of vitamin D. Populations with traditional lifestyles having lifelong, year-round exposure to tropical sunlight might provide us with information on optimal vitamin D status from an evolutionary perspective. We measured the sum of serum 25-hydroxyvitamin D₂ and D₃ (25(OH)D) concentrations of thirty-five pastoral Maasai (34 (SD 10) years, 43 % male) and twenty-five Hadzabe hunter-gatherers (35 (SD 12) years, 84 % male) living in Tanzania. They have skin type VI, have a moderate degree of clothing, spend the major part of the day outdoors, but avoid direct exposure to sunlight when possible. Their 25(OH)D concentrations were measured by liquid chromatography-MS/MS. The mean serum 25(OH)D concentrations of Maasai and Hadzabe were 119 (range 58-167) and 109 (range 71-171) nmol/l, respectively. These concentrations were not related to age, sex or BMI. People with traditional lifestyles, living in the cradle of mankind, have a mean circulating 25(OH)D concentration of 115 nmol/l. Whether this concentration is optimal under the conditions of the current Western lifestyle is uncertain, and should as a possible target be investigated with concomitant appreciation of other important factors in Ca homeostasis that we have changed since the agricultural revolution.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Black People; Calcifediol; Clothing; Developing Countries; Female; Humans; Life Style; Male; Middle Aged; Nutritional Requirements; Rural Health; Skin Pigmentation; Sunlight; Tanzania; Vitamin D Deficiency; Young Adult

Vitamin D status is believed to be best indicated by serum 25-hydroxyvitamin D [25(OH)D; consisting of 25(OH)D₃ and 25(OH)D₂] that are obtained from different sources. Suboptimal vitamin D status is common and associated with adverse health outcomes.. The objectives were to report the prevalence and risk factors of vitamin D deficiency and determine associations of characteristics that have been shown to relate to total 25(OH)D with 25(OH)D₃ and 25(OH)D₂ concentrations.. The Avon Longitudinal Study of Parents and Children is a population-based contemporary birth cohort (children born in 1991-1992) from southwest England.. Seven thousand five hundred sixty children with serum 25(OH)D₃ and 25(OH)D₂ concentrations measured at the mean age of 9.9 yr participated in the study.. Vitamin D deficiency [total 25(OH)D concentration <20 ng/ml] was common (29%). The main risk factors were winter season, less time spent outdoors, low socioeconomic position, nonwhite ethnicity, older age, more advanced puberty stage, and female gender. Although there were some common risk factors for lower 25(OH)D₃ and 25(OH)D₂ concentrations (age, gender, puberty stage, body mass index, physical activity, household income, maternal education), several characteristics were associated with 25(OH)D₃ only (ethnicity, vitamin D intake, time spent outdoors, and UVB protection score) and others with 25(OH)D₂ only (protein and carbohydrate intake, parent's social class, and housing tenure).. Vitamin D deficiency was common in this contemporary U.K. cohort. Despite some overlap, there are differences in potential confounding structures for associations of 25(OH)D₃ and 25(OH)D₂ with health outcomes. These should be accounted for in future studies.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child; Child, Preschool; Cohort Studies; England; Female; Humans; Longitudinal Studies; Male; Prevalence; Prospective Studies; Puberty; Risk Factors; Seasons; Severity of Illness Index; Sex Factors; Socioeconomic Factors; Sunlight; Vitamin D Deficiency

Vitamin D deficiency contributes to skeletal diseases and is highly prevalent among institutionalized elderly patients. Whether low 25-hydroxyvitamin D (25[OH]D) concentrations are an independent risk factor for mortality in these patients is, however, unclear.. We aimed to evaluate whether 25(OH)D concentrations are associated with mortality.. This is a prospective cohort study among elderly female patients (age >70 yr) recruited from 95 nursing homes in Austria.. We calculated Cox proportional hazard ratios (HR) for all-cause mortality according to 25(OH)D quartiles.. We examined 961 study participants (age 83.7 ± 6.1 yr). Median 25(OH)D concentration was 17.5 (interquartile range 13.7-25.5) nmol/liter, and 93% of our cohort had 25(OH)D levels below 50 nmol/liter. During a mean follow-up time of 27 ± 8 months, 284 patients died. Compared with the fourth quartile (25[OH]D >25.5 nmol/liter), the age-adjusted HR (with 95% confidence interval) was 1.49 (1.07-2.10) in the first 25(OH)D quartile (25[OH]D <14.0 nmol/liter), and this association remained significant after multivariate adjustments (HR = 1.56; 95% confidence interval = 1.01-2.40).. This Austrian study suggests that the majority of institutionalized female patients are vitamin D deficient during winter and that there was an inverse association of 25(OH)D and mortality. These data underscore the urgent need for effective strategies for the prevention and treatment of vitamin D deficiency, in particular in the setting of nursing homes.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Aging; Austria; Calcifediol; Cohort Studies; Female; Follow-Up Studies; Frail Elderly; Homes for the Aged; Humans; Mortality; Multivariate Analysis; Nursing Homes; Prevalence; Proportional Hazards Models; Prospective Studies; Seasons; Vitamin D Deficiency

To investigate associations between baseline serum 25-hydroxyvitamin D [25(OH)D] levels and myocardial structure and function after 8 years of follow-up in older Dutch subjects.. We included 256 subjects of the Hoorn Study, a population-based cohort. They underwent a standardized 2-dimensional echocardiogram at baseline between 2000 and 2001, and again between 2007 and 2009. We studied the association of 25(OH)D quartiles with echocardiographic measures of the left ventricular mass index (LVMI), left ventricular systolic function and markers of diastolic function using linear regression analyses.. At baseline, subjects had a mean age of 67.4 ± 5.2 years and 41.4% had prior cardiovascular disease (CVD). Low serum 25(OH)D levels were only associated with higher LVMI at 8-year follow-up in subjects without prior CVD and in subjects with low kidney function (median estimated glomerular filtration rate ≤77.5 ml/min/1.73m(2)). The associations attenuated after adjustments for parathyroid hormone (PTH), which was associated with higher LVMI (g/m(2.7)) in subjects with low kidney function (regression coefficient highest quartile 6.3, 95% CI: 0.2, 12.5).. This study showed no strong associations of 25(OH)D with myocardial structure and function. However, PTH - a possible modifiable mediator in the relation between 25(OH)D and myocardial structure - was positively associated with LVMI in subjects with low kidney function.

Topics: 25-Hydroxyvitamin D 2; Aged; Anthropometry; Blood Glucose; Blood Pressure; Calcifediol; Comorbidity; Diastole; Female; Follow-Up Studies; Glomerular Filtration Rate; Heart; Heart Ventricles; Humans; Hypertrophy, Left Ventricular; Kidney Diseases; Lipids; Male; Middle Aged; Myocardium; Netherlands; Parathyroid Hormone; Risk Factors; Socioeconomic Factors; Systole; Ultrasonography; Vitamin D Deficiency

Low maternal vitamin D levels have been associated with adverse pregnancy outcome. A recent study has suggested that low maternal vitamin D levels at the time of delivery are also associated with an almost fourfold increase in caesarean section risk. The aim of the present study was to investigate whether there is a difference in maternal serum 25-hydroxyvitamin D (25(OH)D) levels at 11-13 weeks' gestation according to the mode of delivery. Maternal serum 25(OH)D levels were measured at 11-13 weeks' gestation in 995 singleton pregnancies resulting in the birth of phenotypically normal neonates at term. The measured 25(OH)D levels were adjusted for maternal age, BMI, racial origin, smoking, method of conception and season of blood testing, and the adjusted levels (multiple of the median; MoM) were compared between those who subsequently delivered vaginally and those that delivered by caesarean section. Delivery was vaginal in 79·6 % of cases, by emergency caesarean section in 11·6 % and by elective caesarean section in 8·8 %. The median 25(OH)D level in our population was 46·82 (interquartile range (IQR) 27·75-70·13) nmol/l. The adjusted maternal median 25(OH)D levels in the emergency and elective caesarean section groups (0·99, IQR 0·71-1·46 MoM and 0·96, IQR 0·73-1·27 MoM, respectively) were not significantly different from the vaginal delivery group (0·99, IQR 0·71-1·33 MoM; P = 0·53 and P = 0·81, respectively). First-trimester maternal serum 25(OH)D levels are similar between women who subsequently have a vaginal delivery and those who deliver by elective or emergency caesarean section.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Calcifediol; Cesarean Section; Elective Surgical Procedures; Emergency Treatment; Female; Humans; London; Nutritional Status; Pregnancy; Pregnancy Complications; Pregnancy Trimester, First; Prospective Studies; Risk; Seasons; Vitamin D; Vitamin D Deficiency

Current recommendations for the treatment of vitamin D deficiency vary from calciferol 800 IU per day to loading doses of vitamin D followed by maintenance therapy of up to 2000 IU per day.. To assess the preparations and doses of vitamin D used to load and maintain patients with serum 25-hydroxyvitamin D (25OHD) <25 nmol/l.. We examined all requests for serum 25OHD over a 12-month period, from September 2009 to 2010 in southwest Scotland. We wrote to all 33 general practices asking whether they usually started replacement therapy with a loading dose and/or recommended over-the-counter maintenance preparations. We accessed the Emergency Care Summary for all patients with serum 25OHD <25 nmol/l to determine whether they had been prescribed maintenance therapy.. Serum 25OHD was requested in 1162 patients. Levels were <25 nmol/l in 282 (24%) patients, only 173 (61%) of whom were receiving vitamin D replacement therapy 3-15 months after diagnosis. Only four (1.4%) were prescribed a loading dose. One hundred and fifty-three (54%) were treated with cholecalciferol or ergocalciferol and 19 (7%) with alfacalcidol or calcitriol. The median dose of chole/ergocalciferol was 800 IU per day, usually in combination with 1200 mg calcium per day.. We have shown a divergence between clinical practice and even the most conservative expert advice for vitamin D replacement therapy. Possible explanations are conflicting advice on treatment and difficulty obtaining suitable vitamin D preparations, particularly high dose vitamin D and vitamin D without calcium, in the UK.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Bone Density Conservation Agents; Calcitriol; Calcium; Cholecalciferol; Data Collection; Dietary Supplements; Dose-Response Relationship, Drug; Drug Compounding; Drug Prescriptions; Ergocalciferols; Female; Humans; Male; Medication Therapy Management; Metabolism; Middle Aged; Nonprescription Drugs; Practice Patterns, Physicians'; Prevalence; Scotland; Vitamin D Deficiency

The objective was to develop evidence-based clinical care guidelines for the screening, diagnosis, management, and treatment of vitamin D deficiency in individuals with cystic fibrosis (CF).. The guidelines committee was comprised of physicians, registered dietitians, a pharmacist, a nurse, a parent of an individual with CF, and a health scientist, all with experience in CF.. Committee members developed questions specific to vitamin D health in individuals with CF. Systematic reviews were completed for each question. The committee reviewed and graded the available evidence and developed evidence-based recommendations and consensus recommendations when insufficient evidence was available. Each consensus recommendation was voted upon by an anonymous process.. Vitamin D deficiency is common in CF. Given the limited evidence specific to CF, the committee provided consensus recommendations for most of the recommendations. The committee recommends yearly screening for vitamin D status, preferably at the end of winter, using the serum 25-hydroxyvitamin D measurement, with a minimal 25-hydroxyvitamin D concentration of 30 ng/ml (75 nmol/liter) considered vitamin D sufficient in individuals with CF. Recommendations for age-specific vitamin D intake for all individuals with CF, form of vitamin D, and a stepwise approach to increase vitamin D intake when optimal vitamin D status is not achieved are delineated.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Age Factors; Calcifediol; Child; Cholecalciferol; Cystic Fibrosis; Dietary Supplements; Ergocalciferols; Evidence-Based Practice; Humans; Infant; Malabsorption Syndromes; Mass Screening; Seasons; Vitamin D; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Age Factors; Calcifediol; Dietary Supplements; Endocrinology; Female; Guidelines as Topic; Health Promotion; Humans; Male; National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division; Nutritional Requirements; Practice Guidelines as Topic; Severity of Illness Index; Societies, Scientific; United States; Vitamin D; Vitamin D Deficiency

In early 2011, a committee convened by the Institute of Medicine issued a report on the Dietary Reference Intakes for calcium and vitamin D. The Endocrine Society Task Force in July 2011 published a guideline for the evaluation, treatment, and prevention of vitamin D deficiency. Although these reports are intended for different purposes, the disagreements concerning the nature of the available data and the resulting conclusions have caused confusion for clinicians, researchers, and the public. In this commentary, members of the Institute of Medicine committee respond to aspects of The Endocrine Society guideline that are not well supported and in need of reconsideration. These concerns focus on target serum 25-hydroxyvitamin D levels, the definition of vitamin D deficiency, and the question of who constitutes a population at risk vs. the general population.

Topics: 25-Hydroxyvitamin D 2; Age Factors; Calcifediol; Calcium, Dietary; Endocrinology; Female; Health Promotion; Humans; Intestinal Absorption; Lactation; Male; National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division; Nutritional Requirements; Parathyroid Hormone; Practice Guidelines as Topic; Pregnancy; Societies, Scientific; United States; Vitamin D; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Cystic Fibrosis; Humans; Pain; Vitamin D; Vitamin D Deficiency

Low vitamin D status has been linked to adiposity, but little is known of the effects of low status in pregnancy on offspring body composition.. The objective was to determine how maternal vitamin D status relates to lean and fat mass of the offspring.. The offspring of 977 pregnant women, who had serum 25-hydroxyvitamin D [25(OH)D] measured at 34 wk gestation, were followed up within 3 wk of birth and at 4 and 6 y of age for dual-energy X-ray absorptiometry assessment of lean and fat mass.. The median maternal serum 25(OH)D concentration was 62 nmol/L (IQR: 43-89 nmol/L); 35% of the women studied had values <50 nmol/L. Lower vitamin D status was associated with lower fat mass in the offspring at birth but with greater fat mass at ages 4 and 6 y. It was not associated with lean mass at any of the ages studied. The opposing associations seen between maternal 25(OH)D (SDs) and fat mass (SDs) in the offspring at birth and at age 6 y were robust to adjustment for a range of confounding factors, including maternal BMI and weight gain in pregnancy [β (95% CI): 0.08 (0.02, 0.15) and -0.10 (-0.17, -0.02), respectively]. The key independent predictors of higher maternal vitamin D status were season of assessment and use of vitamin D supplements.. Lower maternal vitamin D status may be linked to programmed differences in offspring fat mass. The findings require replication but add to a growing evidence base for a role of vitamin D in the origins of adiposity.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Calcifediol; Child; Child, Preschool; Cohort Studies; Female; Follow-Up Studies; Humans; Infant, Newborn; Male; Maternal Nutritional Physiological Phenomena; Nutrition Surveys; Overweight; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Third; Prospective Studies; Seasons; Severity of Illness Index; United Kingdom; Vitamin D Deficiency

There are multiple potential regulators of neonatal vitamin D status of environmental, genetic, and epigenetic origins. The relation between these factors and circulating neonatal vitamin D has yet to be fully characterized.. The aim of this study was to examine the relative contribution of genetic factors, maternal circulating 25-hydroxyvitamin D [25(OH)D] concentrations, and the placental methylation level of the gene that encodes the primary catabolic enzyme of active vitamin D [25(OH)D-24-hydroxylase encoded by CYP24A1] to neonatal 25(OH)D concentrations.. We used the classical twin study design to determine the genetic contribution to neonatal 25(OH)D. A total of 86 twin pairs (32 monozygotic and 54 dizygotic twin pairs) were included in this study. Serum 25(OH)D was measured by using a 25(OH)D kit. CYP24A1 promoter DNA methylation was measured by means of matrix-assisted laser desorption time-of-flight mass spectrometry.. Maternal and neonatal 25(OH)D showed a strong association (R² = 0.19). Monozygotic and dizygotic within-pair serum 25(OH)D correlations were similar (R² = 0.71 and 0.67, respectively), which suggested no genetic effect. Placental CYP24A1 methylation did not show an association with maternal or neonatal 25(OH)D concentrations.. Our results suggest that maternal circulating 25(OH)D is the most significant regulator of neonatal circulating 25(OH)D concentrations, with underlying genetic factors playing a limited role. The placental methylation of the CYP24A1 promoter appears subject to a genetic influence, although no evidence of a relation between the methylation level of this gene and circulating maternal or neonatal 25(OH)D was apparent.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; DNA Methylation; Female; Fetal Blood; Humans; Infant, Newborn; Male; Maternal Nutritional Physiological Phenomena; Placenta; Pregnancy; Pregnancy Complications; Promoter Regions, Genetic; Steroid Hydroxylases; Twins, Dizygotic; Twins, Monozygotic; Victoria; Vitamin D Deficiency; Vitamin D3 24-Hydroxylase

The primary aim of the study was to explore the potential relationship between serum 25-hydroxyvitamin D [25(OH)D] levels and Mini Nutritional Assessment (MNA) score, a surrogate for protein energy undernutrition, in elderly (≥65 years old) subjects with and without a hip fracture. A secondary aim of the study was to provide estimates of the MNA discriminatory performance in the detection of subjects with low levels of 25(OH)D (<20 ng/ml). The study population consisted of 101 patients with a hip fracture, recruited from a single urban Hospital in Athens, Greece, and 85 community dwelling subjects with no history of hip fracture. Serum 25(OH)D was measured, nutritional status was determined by the MNA questionnaire in all subjects, and linear correlation between variables was investigated. Receiver operator characteristic (ROC) curve analysis was performed and discriminatory performance was further assessed by calculating positive and negative likelihood ratios (LR). MNA scores were significantly correlated with 25(OH)D levels (rho=0.685, p<0.001) and this finding was robust in both groups and unaffected by gender. ROC curve analysis demonstrated an area under the curve (AUC) of 0.860 [standard error (SE): 0.026, 95% confidence interval (CI): 0.810-0.910], which provided a significantly better estimation of 25(OH)D status than simple guess (p<0.001). The lowest cutoff value in MNA score, providing a sensitivity over 90% was 25.25, which was associated with a sensitivity of 90.9% and a specificity of 53.6%. The same analysis revealed acceptable results only within hip fracture patients. MNA score might be a satisfactory surrogate marker for 25(OH)D levels with which it is linearly correlated. However, it appears that its discriminatory performance, as a diagnostic tool for 25(OH)D insufficiency, is rather suboptimal.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Biomarkers; Calcifediol; Cohort Studies; Cross-Sectional Studies; Female; Geriatric Assessment; Greece; Hip Fractures; Humans; Male; Nutrition Assessment; Nutritional Status; Osteoporosis; Osteoporotic Fractures; Protein-Energy Malnutrition; Sensitivity and Specificity; Vitamin D Deficiency

Vitamin D deficiency has been associated with several common diseases, including cancer and is being investigated as a possible risk factor for these conditions. We reported the striking prevalence of vitamin D deficiency in Scotland. Previous epidemiological studies have reported an association between low dietary vitamin D and colorectal cancer (CRC). Using a case-control study design, we tested the association between plasma 25-hydroxy-vitamin D (25-OHD) and CRC (2,001 cases, 2,237 controls). To determine whether plasma 25-OHD levels are causally linked to CRC risk, we applied the control function instrumental variable (IV) method of the mendelian randomization (MR) approach using four single nucleotide polymorphisms (rs2282679, rs12785878, rs10741657, rs6013897) previously shown to be associated with plasma 25-OHD. Low plasma 25-OHD levels were associated with CRC risk in the crude model (odds ratio (OR): 0.76, 95% Confidence Interval (CI): 0.71, 0.81, p: 1.4×10(-14)) and after adjusting for age, sex and other confounding factors. Using an allele score that combined all four SNPs as the IV, the estimated causal effect was OR 1.16 (95% CI 0.60, 2.23), whilst it was 0.94 (95% CI 0.46, 1.91) and 0.93 (0.53, 1.63) when using an upstream (rs12785878, rs10741657) and a downstream allele score (rs2282679, rs6013897), respectively. 25-OHD levels were inversely associated with CRC risk, in agreement with recent meta-analyses. The fact that this finding was not replicated when the MR approach was employed might be due to weak instruments, giving low power to demonstrate an effect (<0.35). The prevalence and degree of vitamin D deficiency amongst individuals living in northerly latitudes is of considerable importance because of its relationship to disease. To elucidate the effect of vitamin D on CRC cancer risk, additional large studies of vitamin D and CRC risk are required and/or the application of alternative methods that are less sensitive to weak instrument restrictions.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Case-Control Studies; Chromatography, Liquid; Colorectal Neoplasms; Female; Genotype; Humans; Likelihood Functions; Male; Mendelian Randomization Analysis; Middle Aged; Odds Ratio; Polymorphism, Single Nucleotide; Risk Factors; Scotland; Tandem Mass Spectrometry; Vitamin D Deficiency

Vitamin D plays a role in reproductive capacity. Recently, several investigators have demonstrated higher IVF pregnancy rates in vitamin D replete women. The objective of this study was to validate these findings and to further elucidate the role of vitamin D in reproduction among a diverse group of women.. This was a retrospective cohort study in an academic tertiary care center of 188 infertile women undergoing IVF. Serum levels of vitamin D (25OH-D) were measured in previously frozen serum samples. The main outcome measure was clinical pregnancy, defined as sonographic presence of a heartbeat following IVF.. The relationship between vitamin D status and pregnancy rates differed by race (P < 0.01). Among non-Hispanic whites, pregnancy rates declined with progressively lower levels of vitamin D, while in Asians, the reverse was true. Adjusting for age and number and quality of embryos transferred among non-Hispanic whites, the odds of pregnancy were four times higher in vitamin D replete versus deficient patients. Live birth rates mirrored pregnancy rates. Vitamin D status was not associated with ovarian stimulation parameters or with markers of embryo quality.. Vitamin D deficiency is associated with lower pregnancy rates in non-Hispanic whites, but not in Asians, possibly due to their lower IVF success rates. Vitamin D deficiency was not correlated with ovarian stimulation parameters or with markers of embryo quality, suggesting its effect may be mediated through the endometrium.

Topics: 25-Hydroxyvitamin D 2; Academic Medical Centers; Adult; Asian; Calcifediol; Cohort Studies; Embryo Implantation; Endometrium; Female; Fertilization in Vitro; Humans; Infertility, Female; Live Birth; Los Angeles; Outpatient Clinics, Hospital; Pregnancy; Pregnancy Rate; Prevalence; Retrospective Studies; Severity of Illness Index; Vitamin D Deficiency; White People

Vitamin D deficiency is a global health problem that is associated with increased risks of major diseases. This study investigated the status of 25-hydroxyvitamin D [25(OH)D] and its demographic and lifestyle determinants among Korean adults.. A total of 5,847 adults who had participated in the Korean National Health and Nutrition Examination Survey of 2008 (KNHANES) were included in the present study. Stepwise linear regression analysis was performed to determine the demographic and lifestyle determinants of 25(OH)D concentration.. The weighted prevalence (standard error) of 25(OH)D deficiency (<20 ng/mL) was 49.9 (2.1)% among the males and 67.4 (1.7)% among the females. Severe 25(OH)D deficiencies (<10 ng/mL) were found in 5.7 (0.8)% of the males and 11.1 (1.0)% of the females. These peaked in spring and winter. Only 12.2 (1.1)% of the males and 6.4 (0.6)% of the females exhibited 25(OH)D sufficiency (>=30 ng/mL). The correlates with higher 25(OH)D concentration for both genders included summer, fall (vs spring), the 60s age group (vs 20s), rural residence (vs urban), moderate and vigorous physical activity (vs sedentary), alcohol consumption, and multivitamin supplementation. Higher education and unmarried status were inversely associated with 25(OH)D concentration for both genders. The strongest predictors of 25(OH)D concentration were season and residential area.. 25(OH)D deficiency is a prevalent condition in Korea. Understanding the determinants of 25(OH)D can facilitate identification of persons at risk of 25(OH)D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Aging; Calcifediol; Cross-Sectional Studies; Female; Humans; Life Style; Male; Middle Aged; Nutrition Surveys; Prevalence; Republic of Korea; Risk Factors; Rural Health; Seasons; Severity of Illness Index; Sex Characteristics; Vitamin D Deficiency; Young Adult

We present data from the Korean National Health and Nutritional Examination Survey (KNHANES) 2008-2009 on the association between 25-hydroxyvitamin D[25(OH)D] status and type 2 diabetes in a representative sample of the adult Korean population.. This study was based on data obtained from the KNHANES 2008-2009, which was conducted for 3 years (2007-2009) using a rolling sampling design that involved a complex, stratified, multistage, probability-cluster survey of a representative sample of the noninstitutionalized civilian population of South Korea.. We showed that serum 25(OH)D concentration is inversely associated with type 2 diabetes in the Korean general population. In particular, low serum 25(OH)D concentration was associated with an increased prevalence of type 2 diabetes in young women and old men. The present study showed that 25(OH)D has a significant negative association with fasting insulin and insulin resistance.. The age- and gender-specific association between low 25(OH)D level and type 2 diabetes may be related to interactions between vitamin D, sex hormone concentrations, and type 2 diabetes. In conclusion, we showed that low 25(OH)D concentration is associated with type 2 diabetes in the Korean general population in an age- and gender-specific pattern.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Aging; Calcifediol; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Health Surveys; Humans; Insulin; Insulin Resistance; Male; Middle Aged; Prevalence; Republic of Korea; Sex Factors; Vitamin D Deficiency; Young Adult

Vitamin D status in the Korean population has not been adequately determined.. To investigate the vitamin D status and the prevalence of vitamin D insufficiency in the Korean population, and also identify the predictors for vitamin D insufficiency in Korea.. The Fourth Korea National Health and Nutrition Examination Surveys (KNHANES IV) in the Korean population conducted in 2008.. 3,047 males and 3,878 females aged 10 years and older selected in all the 16 administrative districts of South Korea.. Serum 25-hydroxyvitamin D [25(OH)D] levels and the prevalence of vitamin D insufficiency defined as serum 25(OH)D level of less than 20 ng/ml.. Vitamin D insufficiency was found in 47.3% of males and 64.5% of females, whereas only 13.2% of male and 6.7% of female population had a serum 25(OH)D level of greater than 30 ng/ml. Vitamin D insufficiency was most prevalent in the age of 20-29, with a rate of 65.0% in males and 79.9% in females, and least prevalent in the age of 60-69 in males and 50-59 in females. Those who work usually indoors were more predisposed to vitamin D insufficiency. In the adult population, predictors for vitamin D insufficiency included young age groups, spring and winter seasons, living in an urban area, and indoor occupations.. Vitamin D insufficiency is very common, and it is now a greater threat to the younger generation in Korea. Current recommendations for vitamin D intakes for Koreans are inadequate, especially for the youth.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Age Factors; Aged; Calcifediol; Child, Preschool; Exercise; Female; Forecasting; Humans; Male; Middle Aged; Nutrition Surveys; Nutritional Status; Occupations; Republic of Korea; Risk Factors; Rural Population; Seasons; Sex Factors; Urban Population; Vitamin D Deficiency; Walking; Young Adult

Metabolic consequences of vitamin D deficiency have become a recent research focus. Maternal vitamin D status is thought to influence musculoskeletal health in children, but its relation with offspring metabolic risk is not known.. We aimed to examine the association between maternal vitamin D status and anthropometric variables, body composition, and cardiovascular risk markers in Indian children.. Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured at 28-32 wk gestation in 568 women who delivered at Holdsworth Memorial Hospital, Mysore, India. Anthropometric variables, glucose and insulin concentrations, blood pressure, and fasting lipid concentrations were measured in the offspring at 5 and 9.5 y of age. Muscle-grip strength was measured by using a hand-held dynamometer at age 9.5 y. Arm-muscle area was calculated as a measure of muscle mass. Fasting insulin resistance was calculated by using the homeostasis model assessment equation.. Sixty-seven percent of women had vitamin D deficiency [serum 25(OH)D concentration <50 nmol/L]. At ages 5 and 9.5 y, children born to vitamin D-deficient mothers had smaller arm-muscle area in comparison with children born to mothers without deficiency (P < 0.05). There was no difference in grip strength between offspring of women with and without vitamin D deficiency. At 9.5 y, children of vitamin D-deficient mothers had higher fasting insulin resistance than did children of nondeficient women (P = 0.04). There were no associations between maternal vitamin D status and other offspring risk factors at either age.. Intrauterine exposure to low 25(OH)D concentrations is associated with less muscle mass and higher insulin resistance in children.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Composition; Body Weights and Measures; Cardiovascular Diseases; Child; Child Development; Child, Preschool; Cohort Studies; Female; Humans; India; Insulin Resistance; Male; Maternal Nutritional Physiological Phenomena; Muscle Strength; Nutritional Status; Pregnancy; Pregnancy Trimester, Third; Risk Factors; Vitamin D Deficiency

Studies indicate that low plasma 25-hydroxyvitamin D [25(OH)D] is associated with a range of disease processes, many of which are inflammatory. However, other lipid-soluble vitamins decrease during the systemic inflammatory response, and this response may confound the interpretation of plasma 25(OH)D.. The objective was to examine whether plasma 25(OH)D concentrations change during evolution of the systemic inflammatory response.. Patients (n = 33) who underwent primary knee arthroplasty had venous blood samples collected preoperatively and postoperatively (beginning 6-12 h after surgery and on each morning for 5 d) for the measurement of 25(OH) D, vitamin D-binding protein, parathyroid hormone (PTH), calcium, C-reactive protein, and albumin. A final sample was collected at 3 mo.. Preoperatively, most patients were 25(OH)D deficient (<50 nmol/L) and had secondary hyperparathyroidism (PTH > 5 pmol/L). Age, sex, body mass index, season, medical history, and medication use were not associated with significant differences in preoperative plasma 25(OH)D concentrations. By day 2 there was a large increase in C-reactive protein concentrations (P < 0.001) and a significant decrease in 25(OH)D of ≈40% (P < 0.001). C-reactive protein, 25(OH)D, and calculated free 25(OH)D had not returned to preoperative concentrations by 5 d postoperatively (all P < 0.001). At 3 mo, 25(OH)D and free 25(OH)D remained significantly lower (20% and 30%, respectively; P < 0.01).. Plasma concentrations of 25(OH)D decrease after an inflammatory insult and therefore are unlikely to be a reliable measure of 25(OH)D status in subjects with evidence of a significant systemic inflammatory response.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Algorithms; Arthroplasty, Replacement, Knee; C-Reactive Protein; Calcifediol; Elective Surgical Procedures; Female; Humans; Hyperparathyroidism, Secondary; Male; Middle Aged; Nutritional Status; Osteoarthritis; Statistics, Nonparametric; Systemic Inflammatory Response Syndrome; Time Factors; Vitamin D Deficiency; Vitamin D-Binding Protein

To explore associations between vitamin D and cardiovascular disease risk factors in young European adults.. This was a cross-sectional analysis of serum 25-hydroxyvitamin D [s25(OH)D], intact parathyroid hormone (iPTH) and biomarkers of cardiovascular disease risk in 195 healthy 20- to 40-year-olds (109 women) with a BMI between 27.5 and 32.5 from Iceland (64° N; n = 82), Ireland (51° N; n = 37) and Spain (42° N; n = 76) during mid-late winter.. The median s25(OH)D was 52.8 nmol/l (IQR 38.1-69.9) or 21.1 ng/ml (IQR 15.2-28.0) with a latitude-dependent gradient (p ≤ 0.0001): Iceland, 41.7 nmol/l (IQR 32.7-54.2) or 16.7 ng/ml (IQR 13.1-21.7); Ireland, 52.9 nmol/l (IQR 35.3-68.6) or 21.2 ng/ml (IQR 14.1-27.4), and Spain, 67.1 nmol/l (IQR 47.1-87.1) or 26.8 ng/ml (IQR 18.8-34.8). Eleven percent of Icelandic participants had s25(OH)D concentrations <25 nmol/l (10 ng/ml) and 66% of Icelandic, 43% of Irish, and 30% of Spanish volunteers had concentrations <50 nmol/l (20 ng/ml), respectively. Overall, 17% met 3 or more of the NCEP/ATP III criteria for cardio-metabolic syndrome (MetS). Participants in the lowest third of s25(OH)D [≤ 42.5 nmol/l (17 ng/ml)] were more likely to have MetS (OR 2.49, p = 0.045) and elevated TAG (OR 3.46, p = 0.019). Individuals with iPTH concentrations in the lowest third [2.34 pmol/l (22.2 pg/ml)] were more likely to have elevated fasting TAG (OR 4.17, p = 0.039), insulin (OR 3.15, p = 0.029) and HOMA-IR (OR 2.15, p = 0.031), and they were less likely to have elevated IL-6 (OR 0.24, p = 0.003).. There were interactions between s25(OH)D, iPTH and cardio-metabolic risk factors which, given the increasing prevalence of overweight and obesity and a low vitamin D status among adults, require randomised controlled vitamin D intervention studies in overweight persons.

Topics: 25-Hydroxyvitamin D 2; Adult; Calcifediol; Cardiovascular Diseases; Cross-Sectional Studies; Female; Humans; Hypertriglyceridemia; Iceland; Insulin Resistance; Interleukin-6; Ireland; Male; Metabolic Syndrome; Nutritional Status; Overweight; Parathyroid Hormone; Prevalence; Risk Factors; Seasons; Spain; Vitamin D Deficiency; Young Adult

Vitamin D deficiency is common. Recently Roche Diagnostics removed their Elecsys Vitamin D3 (25OH) electrochemiluminescence immunoassay (ECLIA) from use, citing deteriorating traceability to the reference method (liquid chromatography tandem mass spectrometry; LCMSMS). We investigated the performance of the Roche assay (2 assay formulations) against an LCMSMS method and the widely used DiaSorin radioimmunoassay (RIA) method.. Two sets of samples from separate populations were assayed for vitamin D. The first set was assayed using three different methods: RIA (DiaSorin) in 2004, polyclonal ECLIA (Roche) in early 2009 and LCMSMS in early 2010. The second set was assayed using polyclonal and monoclonal ECLIA (Roche) and LCMSMS in mid-2010.. The correlation of the polyclonal ECLIA with the RIA was poor (ECLIA = 0.45 × RIA + 19, r(2) = 0.59, n = 773). LCMSMS results correlated with RIA (RIA = 0.86 × LCMSMS + 4, r(2) = 0.69, n = 49) better than with polyclonal ECLIA (polyclonal ECLIA = 0.55 × LCMSMS + 6, r(2) = 0.62, n = 55) despite a storage interval of 6 years.In recently collected samples monoclonal and polyclonal immunoassays gave similar results (monoclonal ECLIA = 0.93 polyclonal ECLIA -3, r(2) = 0.60, n = 153). The correlation between monoclonal Roche ECLIA and LCMSMS in these samples was very poor (monoclonal ECLIA = 0.31 × LCMSMS + 23, r(2) = 0.27).. At the time of its removal from the market, the Roche Elecsys Vitamin D3 (25OH) assay showed unacceptable performance, underestimating vitamin D levels. It seems that this bias preceded the introduction of the monoclonal assay. The worldwide distribution of the assay and the duration of this bias likely led to a significant number of patients starting supplementation unnecessarily.

Topics: 25-Hydroxyvitamin D 2; Cholecalciferol; Chromatography, Liquid; Diagnostic Errors; Humans; Immunoassay; Tandem Mass Spectrometry; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Adult; Antarctic Regions; Calcifediol; Dietary Supplements; Female; Humans; Male; Models, Biological; Nutrition Policy; Nutritional Requirements; Obesity; Reproducibility of Results; Vitamin D; Vitamin D Deficiency

Vitamin D status in infants depends on supplementation. We examined the vitamin D status in relation to supplementation dose and scheme in infants.. One hundred thirty-four infants age 6 months and 98 infants age 12 months (drop out 27%) were investigated. Vitamin D intake (diet, supplements), anthropometry, and 25-hydroxyvitamin D (25-OHD) serum concentration at the 6th and 12th months were assessed.. Vitamin D intake of 1062 ± 694 IU at the 6th month was not different from that at the 12th month (937 ± 618 IU). Vitamin D intake expressed in international units per kilogram of body weight decreased from 141 ± 80 IU/kg at the 6th month to 93 ± 62 IU/kg at the 12th month (P < 0.0001), which was associated with a reduction in 25-OHD from 43 ± 20 ng/mL to 29 ± 12 ng/mL, respectively (P < 0.0001). In the subgroup of everyday supplemented infants (n = 43), vitamin D intake decreased from 143 ± 88 IU/kg at the 6th month to 118 ± 60 IU/kg at the 12th month (P < 0.05), which coincided with a reduction of 25-OHD from 40 ± 19 ng/mL to 32 ± 13 ng/mL (P < 0.01). In the subgroup with variable supplementation habits (n = 32), vitamin D intake decreased from 146 ± 79 IU/kg to 77 ± 56 IU/kg (P < 0.001), which was associated with a reduction of 25-OHD from 42 ± 21 ng/mL to 25 ± 8 ng/mL (P < 0.0001). 25-OHD concentration change between the 6th and the 12th months negatively correlated with the 25-OHD level assessed at the 6th month (r = -0.82; P < 0.0001).. Vitamin D supplementation of infants should consider their rapid body weight increment. We postulate vitamin D daily dose close to 100 IU/kg body weight as favorable for infants up to age 12 months.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Child Development; Cohort Studies; Diet; Dietary Supplements; Female; Humans; Infant; Male; Nutrition Policy; Nutritional Status; Patient Compliance; Patient Dropouts; Poland; Prevalence; Prospective Studies; Vitamin D; Vitamin D Deficiency; Weight Gain

Early menarche is a risk factor for cardiometabolic disease and cancer. Latitude, which influences sun exposure, is inversely related to age at menarche. This association might be related to vitamin D, but to our knowledge it has not been investigated in prospective epidemiologic studies.. We studied the association between vitamin D status and the occurrence of menarche in a prospective study in girls from Bogota, Colombia.. We measured plasma 25-hydroxyvitamin D [25(OH)D] concentrations in a random sample of 242 girls (mean ± SD age: 8.8 ± 1.6 y) and followed them for a median of 30 mo. Girls were asked periodically about the occurrence and date of menarche. Baseline 25(OH)D concentrations were categorized as <50 nmol/L (deficient), ≥50 and <75 nmol/L, or ≥75 nmol/L (sufficient). The incidence of menarche was compared between groups by using time-to-event analyses.. A total of 57% of girls in the vitamin D-deficient group reached menarche during follow-up compared with 23% of girls in the vitamin D-sufficient group (P-trend = 0.0004). The estimated mean (±SE) ages at menarche in the same groups were 11.8 ± 0.2 y and 12.6 ± 0.2 y, respectively (P = 0.0009). After adjustment for baseline age and BMI-for-age z score in a Cox proportional hazards model, the probability of menarche was twice as high in vitamin D-deficient girls than in girls who were vitamin D-sufficient (HR: 2.05; 95% CI: 1.03, 4.07; P = 0.04). Similar results were obtained in girls aged ≥9 y at baseline (HR: 2.39; 95% CI: 1.14, 5.00; P = 0.02).. Vitamin D deficiency is associated with earlier menarche.

Topics: 25-Hydroxyvitamin D 2; Age Factors; Body Mass Index; Calcifediol; Child; Child Development; Child, Preschool; Colombia; Female; Humans; Longitudinal Studies; Menarche; Proportional Hazards Models; Prospective Studies; Puberty, Precocious; Severity of Illness Index; Vitamin D Deficiency

The prevalence of vitamin D deficiency and its consequences on bone in pediatric bone fragility disorders is not well characterized. In the present study, we evaluated determinants of vitamin D status in children and adolescents with osteogenesis imperfecta (OI) and assessed the relationship between 25-hydroxyvitamin D (25OH D) serum concentrations and lumbar spine areal bone mineral density (LS-aBMD).. This retrospective cross-sectional study comprised 315 patients with a diagnosis of OI type I, III, or IV (aged 1.1-17.9 yr; 161 girls) who had not received bisphosphonate treatment at the time of 25OH D analysis. In 282 patients (90%), LS-aBMD measurements were available at the same time.. Serum concentrations of 25OH D ranged from 14 to 133 nmol/liter and were less than 50 nmol/liter in 86 patients (27%). Regression analysis revealed that age (P < 0.001), season (P < 0.001), and OI severity (P = 0.048), but not gender, were significant independent predictive factors of 25OH D levels. Serum 25OH D concentrations were negatively correlated with serum PTH levels (P = 0.003) and urinary cross-linked N-telopeptides of type I collagen to creatinine ratios (P = 0.005). Serum 25OH D levels were positively associated (P = 0.02) with LS-aBMD z-scores after accounting for OI severity, age, and gender.. Serum 25OH D levels are positively associated with LS-aBMD z-scores in children and adolescents with OI types I, III, and IV.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Aging; Anthropometry; Bone Density; Calcifediol; Child; Child, Preschool; Cross-Sectional Studies; Female; Humans; Infant; Lumbar Vertebrae; Male; Nutritional Status; Osteogenesis Imperfecta; Regression Analysis; Retrospective Studies; Seasons; Vitamin D; Vitamin D Deficiency; Young Adult

An association between vitamin D status and sarcopenia has not been shown in a community-dwelling cohort, despite the well-documented relationship between vitamin D status and falls.. Our objective was to investigate whether vitamin D level is associated with sarcopenia in older Koreans.. The Fourth Korea National Health and Nutrition Examination Survey in the Korean population was conducted in 2009.. Participants included 1380 men and 1789 women aged 50 yr or older.. Serum 25-hydroxyvitamin D [25(OH)D] and PTH levels were measured. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight that was less than 2 sd below the sex-specific mean for young adults. Obesity was defined as a body mass index (BMI) of 27.5 kg/m(2) or higher.. 25(OH)D level correlated negatively with appendicular fat mass and positively with appendicular skeletal mass. The groups with sarcopenic obesity and sarcopenia only had lower 25(OH)D levels than did the nonsarcopenia groups. However, 25(OH)D levels did not differ between the sarcopenic obesity and sarcopenia groups. After adjustment for age, sex, BMI, and lifestyle factors, compared with those in the lowest quartile of 25(OH)D level, participants in the highest quartile had an odds ratio for sarcopenia of 0.47 (95% confidence interval = 0.30-0.73; P for trend = 0.001). There was no association between PTH and sarcopenia after adjustment of BMI.. Vitamin D levels were significantly lower in subjects with sarcopenia than in those without, regardless of obesity. We found a strong inverse association between 25(OH)D level and sarcopenia in the older Korean population.

Topics: 25-Hydroxyvitamin D 2; Aged; Asian People; Body Mass Index; Calcifediol; Cross-Sectional Studies; Female; Health Surveys; Humans; Male; Middle Aged; Nutrition Surveys; Obesity; Parathyroid Hormone; Republic of Korea; Risk Factors; Sarcopenia; Vitamin D Deficiency

To assess the correlation between the levels of vitamin D in follicular fluid and serum, and to determine whether the level of 25-hydroxyvitamin D (25OH-D) in follicular fluid of infertile women undergoing assisted reproductive technology (ART) is associated with the outcome.. Eighty-two infertile women undergoing ART at an academic tertiary care centre were recruited for a prospective cohort study. Levels of 25OH-D in follicular fluid and serum were measured. Standardized regimens for pituitary downregulation and controlled ovarian hyperstimulation were employed. Patient and cycle parameters, and clinical pregnancy (defined as evidence of intra-uterine gestation sac plus heart rate on ultrasound) were determined.. A significant correlation was found between the levels of vitamin D in follicular fluid and serum (r=0.767, p=0.001). The overall rates of chemical, clinical and ongoing pregnancy were 35.5% (n=29), 29.3% (n=24) and 23.2% (n=19), respectively. No significant difference was found in these pregnancy rates between the tertiles of 25OH-D level in follicular fluid (p=0.959, 0.995 and 0.604, respectively). The median serum level of vitamin D was 8.13 (range 5.37-13.62)ng/ml in the clinically pregnant group and 8.29 (range 5.93-21.23)ng/ml in the non-pregnant group (p=0.235). Interestingly, the median level of vitamin D in follicular fluid was 9.19 (range 5.25-19.51)ng/ml in the clinically pregnant group and 10.34 (range 5.89-29.69)ng/ml in the non-pregnant group (p=0.433). The fertilization rate decreased significantly and the implantation rate increased (not significantly) with increasing tertiles of 25OH-D level in follicular fluid.. The level of 25OH-D in follicular fluid is reflective of body stores of vitamin D. Most subjects in this study were deficient in vitamin D, but this study found that vitamin D deficiency does not play a pivotal role in the outcome of ART.

Topics: 25-Hydroxyvitamin D 2; Academic Medical Centers; Calcifediol; Cohort Studies; Embryo Implantation; Embryo Transfer; Female; Fetal Development; Follicular Fluid; Humans; Infertility, Female; Iran; Predictive Value of Tests; Pregnancy; Pregnancy Rate; Prevalence; Prospective Studies; Reproductive Techniques, Assisted; Sperm Injections, Intracytoplasmic; Vitamin D; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Atherosclerosis; Calcinosis; Cross-Sectional Studies; Female; Frail Elderly; Hospitalization; Humans; Male; Reference Values; Vitamin D; Vitamin D Deficiency

The aim of the study was to investigate the association between vitamin D intake and status and the risk of islet autoimmunity (IA) and subsequent type 1 diabetes in children at increased risk of type 1 diabetes.. The Diabetes Autoimmunity Study in the Young (DAISY) in Denver, CO, USA, has been following children at increased risk of diabetes since 1993. As of February 2011, 198 children developed IA during follow-up of 2,644 DAISY children. Vitamin D intake and plasma 25-hydroxyvitamin D [25(OH)D] were measured longitudinally. Proportional hazards regression analyses of time to IA, or type 1 diabetes in IA-positive children, were conducted, with vitamin D intake and 25(OH)D as time-varying covariates. HRs were calculated for a standard deviation difference in exposure, with adjustment for confounders.. Intake of vitamin D was not associated with the risk of IA (adjusted HR 1.13; 95% CI 0.95, 1.35; p = 0.18) nor progression to diabetes in IA-positive children (adjusted HR 1.30; 95% CI 0.91, 1.86; p = 0.15). Moreover, 25(OH)D level was not associated with the risk of IA (adjusted HR 1.12; 95% CI 0.88, 1.43; p = 0.36), nor progression to diabetes in IA-positive children (adjusted HR 0.91; 95% CI 0.68, 1.22; p = 0.54). In the 128 children in whom we measured 25(OH)D at 9 months of age, 25(OH)D was not associated with risk of IA (n = 30 IA-positive children) (adjusted HR 1.02; 95% CI 0.96, 1.07; p = 0.58).. Neither vitamin D intake nor 25(OH)D levels throughout childhood were associated with the risk of IA or progression to type 1 diabetes in our population.

Topics: 25-Hydroxyvitamin D 2; Autoimmunity; Calcifediol; Child; Child, Preschool; Cohort Studies; Colorado; Diabetes Mellitus, Type 1; Diet; Dietary Supplements; Female; Humans; Infant; Infant, Newborn; Islets of Langerhans; Longitudinal Studies; Male; Prospective Studies; Risk; Surveys and Questionnaires; Vitamin D; Vitamin D Deficiency

The Institutes of Medicine (IOM) recently revised the recommended dietary allowances (RDA) for vitamin D, to maintain serum 25-hydroxyvitamin D (25(OH)D) at or above 50 nmol/L, to sustain bone density, calcium absorption, and to minimize risk of osteomalacia and rickets. However there are compelling reasons why 25(OH)D should preferably exceed 75 nmol/L: (A) Scrutiny of actual data specified by the IOM relating 25(OH)D to bone density and osteomalacia shows the desirable minimum 25(OH)D to be 75 nmol/L (30 ng/mL). (B) Humans are primates, optimized through evolution to inhabit tropical latitudes, with serum 25(OH)D over 100 nmol/L. (C) Epidemiologic relationships show health benefits if 25(OH)D levels exceed 70 nmol/L; these include fewer falls, better tooth attachment, less colorectal cancer, improved depression and wellbeing. Some studies of populations at high-latitude relate higher 25(OH)D to risk of prostate cancer, pancreatic cancer or mortality. Those relationships are attributable to the dynamic fluctuations in 25(OH)D specific to high latitudes, and which can be corrected by maintaining 25(OH)D at steady, high levels throughout the year, the way they are in the tropics. (D) There are now many clinical trials that show benefits and/or no adversity with doses of vitamin D that raise serum 25(OH)D to levels beyond 75 nmol/L. Together, the evidence makes it very unlikely that further research will change the conclusion that risk of disease with serum 25(OH)D higher than 75 nmol/L is lower than the risk of disease if the serum 25(OH)D is approximately 53 nmol/L.

Topics: 25-Hydroxyvitamin D 2; Adult; Animals; Calcifediol; Child; Humans; National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division; Nutrition Policy; Practice Guidelines as Topic; United States; Vitamin D; Vitamin D Deficiency

To examine the prospective associations of baseline vitamin D [25-hydroxyvitamin D; 25(OH)D] with insulin resistance (IR), β-cell function, and glucose homeostasis in subjects at risk for type 2 diabetes.. We followed 489 subjects, aged 50 ± 10 years, for 3 years. At baseline and follow-up, 75-g oral glucose tolerance tests (OGTTs) were administered. IR was measured using the Matsuda index (IS(OGTT)) and the homeostasis model assessment of IR (HOMA-IR), β-cell function was determined using both the insulinogenic index divided by HOMA-IR (IGI/IR) and the insulin secretion sensitivity index-2 (ISSI-2), and glycemia was assessed using the area under the glucose curve (AUC(glucose)). Regression models were adjusted for age, sex, ethnicity, season, and baseline value of the outcome variable, as well as baseline and change in physical activity, vitamin D supplement use, and BMI.. Multivariate linear regression analyses indicated no significant association of baseline 25(OH)D with follow-up IS(OGTT) or HOMA-IR. There were, however, significant positive associations of baseline 25(OH)D with follow-up IGI/IR (β = 0.005, P = 0.015) and ISSI-2 (β = 0.002, P = 0.023) and a significant inverse association of baseline 25(OH)D with follow-up AUC(glucose) (β = -0.001, P = 0.007). Progression to dysglycemia (impaired fasting glucose, impaired glucose tolerance, or type 2 diabetes) occurred in 116 subjects. Logistic regression analyses indicated a significant reduced risk of progression with higher baseline 25(OH)D (adjusted odds ratio 0.69 [95% CI 0.53-0.89]), but this association was not significant after additional adjustment for baseline and change in BMI (0.78 [0.59-1.02]).. Higher baseline 25(OH)D independently predicted better β-cell function and lower AUC(glucose) at follow-up, supporting a potential role for vitamin D in type 2 diabetes etiology.

Topics: 25-Hydroxyvitamin D 2; Adult; Algorithms; Body Mass Index; Calcifediol; Cohort Studies; Diabetes Mellitus, Type 2; Disease Progression; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Hyperglycemia; Insulin; Insulin Resistance; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Ontario; Prospective Studies; Risk Factors; Vitamin D Deficiency

Vitamin D insufficiency is commonly observed in the general population; observational studies have suggested an association with increased risk of cancer development. We examined the clinical and prognostic relevance of low plasma levels of 25-hydroxyvitamin D (25[OH]D) in myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS). A total of 409 patients were studied: 247 (60%) with primary myelofibrosis (PMF), 74 (18%) with de novo MDS, 63 (15%) with polycythemia vera (PV), and 25 (6%) with essential thrombocythemia (ET). Plasma 25(OH)D levels were measured by liquid chromatography-tandem mass spectrometry; a level lower than 25 ng/mL indicated vitamin D insufficiency and a level lower than 10 ng/mL indicated severe deficiency. The proportion of patients with 25(OH)D insufficiency was significantly greater in PMF (48%) and PV (43%) when compared with ET (28%) and MDS (28%) (P = 0.01). Severe 25(OH)D deficiency was significantly more frequent in ET (12%) and PMF (9%), compared with PV (3%) and MDS (1%) (P = 0.05). There were no significant correlations between 25(OH)D insufficiency, or severe deficiency, and a variety of clinical or laboratory variables in PMF, MDS, or PV. Furthermore, Vitamin D insufficiency did not influence either overall or leukemia-free survival in PMF, MDS, or PV (P > 0.05). We conclude that while hypovitaminosis D is relatively common in MPN and MDS, its clinical relevance for prognosis is limited.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Calcifediol; Cohort Studies; Female; Follow-Up Studies; Humans; Male; Middle Aged; Myelodysplastic Syndromes; Myeloproliferative Disorders; Prevalence; Prognosis; Severity of Illness Index; Survival Analysis; United States; Vitamin D Deficiency; Young Adult

There is growing evidence that vitamin D may have immunomodulatory properties in Crohn's disease (CD). The aim of this study was to determine if serum 25-hydroxy-vitamin D [25(OH)D] was associated with inflammatory cytokines, IL-10, and TNF-alpha levels in patients with inactive CD.. This was a prospective study of 75 adults with quiescent CD. Serum 25(OH)D was measured by radioimmunoassay and serum IL-10 and TNF-alpha by ELISA. Disease activity was assessed by the Crohn's disease activity index (CDAI) and C-reactive protein (CRP).. IL-10 levels were significantly lower in patients with vitamin D insufficiency compared with the vitamin D replete group (mean and SE 2.48 ± 0.51 v 6.77 ± 2.49 pg/mL, p < 0.001). There were, however, no differences in serum TNF-alpha or CRP levels based on vitamin D status. The use of a vitamin D supplement at a low dose (200 IU) did not significantly influence IL-10 levels.. Circulating levels of IL-10, but not TNF-alpha, were significantly lower in CD patients with inadequate serum 25(OH)D. This suggests that poor vitamin D status may be linked to reduced anti-inflammatory capacity in this group.

Topics: 25-Hydroxyvitamin D 2; Adult; Anti-Inflammatory Agents; Calcifediol; Crohn Disease; Cross-Sectional Studies; Cytokines; Dietary Supplements; Drug Resistance; Female; Humans; Immunosuppressive Agents; Interleukin-10; Ireland; Male; Outpatient Clinics, Hospital; Prospective Studies; Severity of Illness Index; Vitamin D; Vitamin D Deficiency

It has previously been shown that there is a threshold of serum 25-hydroxy vitamin D below which secondary hyperparathyroidism may occur. Our purpose was to estimate this threshold in a population of migrant African women living in Paris.. Between February 2008 and December 2009, measurements of 25-hydroxy vitamin D and parathormone were performed in 165 African migrant women living in Paris. The estimation of 25-hydroxy vitamin D and parathormone marginal distributions as Gaussian mixtures, combined with a nonparametric kernel estimation method of the regression function of parathormone on 25-hydroxy vitamin D, provided the desired estimate of serum 25-hydroxy vitamin D threshold.. In our sample of African women, our method has shown that serum 25-hydroxy vitamin D levels below 48 ± 2 nmol/L may induce an increase in parathormone concentrations.. In this sample, our method provided a reliable estimate (95 % confidence interval) of the serum 25-hydroxy vitamin D level below which an increase in parathormone concentrations can be observed.

Topics: 25-Hydroxyvitamin D 2; Adult; Africa; Calcifediol; Diet; Emigrants and Immigrants; Female; Humans; Hyperparathyroidism, Secondary; Middle Aged; Normal Distribution; Parathyroid Hormone; Paris; Severity of Illness Index; Surveys and Questionnaires; Vitamin D Deficiency

The effectiveness of current treatment recommendations for vitamin D insufficiency in children with CF is unknown. Therefore, we assessed the effectiveness of vitamin D(2) 50,000 IU once daily for 28 days for vitamin D insufficiency.. Retrospective chart review of pediatric CF patients from 2006-2008. Vitamin D(2) 50,000 IU daily for 28 days was given to patients with 25-OHD <30 ng/mL and repeat 25-OHD levels were obtained after completion of therapy.. One hundred forty-seven levels from 97 individuals were assessed. Success of treatment was 54% (n=80/147). Seventeen of 39 patients (43%) followed for an additional 6-18 months were able to maintain levels of >or=30 ng/mL.. Vitamin D(2) 50,000 IU daily for 28 days was effective in correcting vitamin D insufficiency in approximately 50% of subjects. However, almost half of successfully treated patients were unable to maintain normal 25-OHD levels >6 months after completion of therapy, implying that this effect is transient.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Child; Child, Preschool; Cystic Fibrosis; Dose-Response Relationship, Drug; Drug Administration Schedule; Ergocalciferols; Female; Follow-Up Studies; Humans; Male; Prevalence; Retrospective Studies; Seasons; Time Factors; Treatment Outcome; Vitamin D Deficiency; Vitamins

There have been methodological problems for studying hypovitaminosis D and K in the elderly. First, studies were done either by evaluating food intake or measuring their circulating levels, but rarely by both in Japan. In this paper, vitamin D and K intakes and their circulating levels were simultaneously determined. Second issue is whether hypovitaminosis D and K are independent of general malnutrition, prevalent in the elderly. We tried to statistically discriminate them by principal component analysis (PCA). Fifty institutionalized elderly were evaluated for their circulating 25 hydroxy-vitamin D (25OH-D), intact parathyroid hormone (PTH), phylloquinone (PK), menaquinone-7 (MK-7) levels, and their food intake. Although average vitamin D intake (7.0 microg/day) exceeded the Japanese Adequate Intake (AI) of 5.0 microg/day, average serum 25OH-D concentration was in the hypovitaminosis D range (11.1 ng/mL). Median vitamin K intake was 168 microg/day, approximately 2.5 times as high as AI for vitamin K. Nevertheless, plasma PK and MK-7 concentrations were far lower than those of healthy Japanese elderly over 70 years old. PCA yielded four components; each representing overall nutritional, vitamin K2, vitamin D, and vitamin K1 status, respectively. Since these components are independent of each other, vitamin D- and K-deficiency in these subjects could not be explained by overall malnutrition alone. In summary, institutionalized elderly had a high prevalence of hypovitaminosis D and K, and the simultaneous determination of their circulating level and dietary intake is mandatory in such studies. PCA would yield fruitful results for eliminating the interference by confounders in a cross-sectional study.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Biomarkers; Body Mass Index; Calcifediol; Diet; Female; Humans; Institutionalization; Japan; Male; Malnutrition; Nutritional Status; Parathyroid Hormone; Principal Component Analysis; Sex Characteristics; Vitamin D Deficiency; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency

Despite increased awareness of the adverse health effects of low vitamin D status, few studies have evaluated 25-hydroxyvitamin D [25(OH)D] status in young children.. We aimed to assess vitamin D status on the basis of 25(OH)D and its relation with parathyroid hormone (PTH) and to identify possible predictors of 25(OH)D status in young children living in a country with minimal vitamin D fortification.. Serum 25(OH)D and PTH concentrations were measured in a cross-sectional sample of children aged 12-22 mo [n = 193 for 25(OH)D, n = 144 for PTH] living in Dunedin, New Zealand (latitude: 45 degrees S). Anthropometric, dietary, and sociodemographic data were collected.. The majority of children sampled in the summer (94%; 47 of 50) had 25(OH)D >50 nmol/L; however, nearly 80% of children sampled in the winter (43 of 55) had serum concentrations < or =50 nmol/L. In season-adjusted multivariate analysis, breastfeeding and higher levels of education were independently associated with lower 25(OH)D concentrations, whereas male sex and cigarette-smoke exposure were positively associated with 25(OH)D (all P < 0.05). Fractional polynomial regression was used to describe the nonlinear relation between serum PTH and 25(OH)D (P < 0.001). When 25(OH)D concentrations were >60-65 nmol/L, a plateau in PTH was evident.. Seasonal variation in 25(OH)D concentration implies that postsummer vitamin D stores were insufficient to maintain status >50 nmol/L year-round. Examination of the predictors of 25(OH)D in our model shows few modifiable risk factors, and thus effective dietary strategies may be required if future research determines that children with 25(OH)D concentrations <50 nmol/L are at significant health risk. This trial was registered at www.actr.org.au as ACTRN12605000487617.

Topics: 25-Hydroxyvitamin D 2; Breast Feeding; Child, Preschool; Educational Status; Female; Humans; Male; New Zealand; Parathyroid Hormone; Predictive Value of Tests; Regression Analysis; Risk Factors; Seasons; Sex Characteristics; Sunlight; Vitamin D; Vitamin D Deficiency

Low levels of vitamin D and excess body weight are both factors associated with increased risk of cancer. The increased risk seems to be proportional to the increase in BMI, and to decrease in serum 25-hydroxyvitamin D (25(OH)D) level. Our earlier investigations suggest that serum 25(OH)D levels decrease with increasing BMI. Although the connection between cancer risk, BMI and vitamin D status might be arbitrary, it has not been discussed in the literature so far. In this study, we analyze data published in current meta-analysis, prospective studies, and systematic reviews on cancer-specific risk attributed to high BMI and low vitamin D status. The contribution of low 25(OH)D levels associated with high BMI to increased cancer risk was calculated for 13 vitamin-D-sensitive cancers with a focus on colorectal and breast cancer as the most frequently studied vitamin-D-sensitive cancer types. Our study suggests that a low vitamin D status may explain at least 20% of the cancer risk attributable to high BMI. The contribution of low 25(OH)D to the increased cancer risk with increasing BMI may be different for different cancer types. Thus, we find 40% for breast cancer, and 26 and 75% for colorectal cancer in men and women, respectively.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Mass Index; Breast Neoplasms; Calcifediol; Colorectal Neoplasms; Female; Humans; Male; Middle Aged; Neoplasms; Obesity; Prevalence; Risk Factors; Sex Factors; Vitamin D Deficiency; Young Adult

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Bone and Bones; Bone Diseases; Cohort Studies; Diet; Female; Fractures, Bone; Humans; Longitudinal Studies; Male; Middle Aged; Nutritional Physiological Phenomena; Osteoporosis; Sunlight; Vitamin D; Vitamin D Deficiency; Vitamins

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Dietary Supplements; Food, Fortified; Humans; Nutrition Policy; Nutritional Requirements; Vitamin D; Vitamin D Deficiency

Data from human studies that have investigated the association between vitamin D status and cognitive function in elderly adults are conflicting. The objective of this study was to assess vitamin D status (reflected by serum 25-hydroxyvitamin D (25(OH)D)) in older European subjects (n=387; aged 55-87 years) and examine its association with measures of cognitive function.. Serum 25(OH)D was assessed using enzyme-linked immunosorbent assay, whereas measures of cognitive function were assessed using a comprehensive Cambridge Neuropsychological Testing Automated Battery (CANTAB).. In all, 12, 36 and 64% of subjects had serum 25(OH)D concentrations <30, <50 and <80 nmol/l, respectively, throughout the year. Serum 25(OH)D was significantly and inversely correlated with four assessments within the spatial working memory (SWM) test parameter (SWM between errors (r=-0.166; P=0.003); SWM between errors 8 boxes (r=-0.134; P=0.038); SWM strategy (r=-0.246; P<0.0001); and SWM total errors (r=-0.174; P<0.003)). When subjects were stratified on the basis of tertiles (T) of serum 25(OH)D (<47.6 (T(1)); 47.6-85.8 (T(2)); and >85.8 (T(3)) nmol/l), fewer errors in SWM test scores occurred in subjects in the third T when compared with the first T (P<0.05-0.084). Stratification by sex showed that these differences between tertiles strengthened (P<0.001-0.043) in the females, but the differences were not significant (P>0.6) in males.. Vitamin D insufficiency, but not deficiency, is widespread in the older population of several European countries. Low vitamin D status was associated with a reduced capacity for SWM, particularly in women.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Aging; Calcifediol; Cognition; Cognition Disorders; Europe; Female; Humans; Male; Memory Disorders; Memory, Short-Term; Middle Aged; Neuropsychological Tests; Nutritional Status; Risk Factors; Severity of Illness Index; Sex Factors; Vitamin D Deficiency

In adults, maximal suppression of serum parathyroid hormone (PTH) has commonly been used to determine the sufficiency of serum 25-hydroxyvitamin D [25(OH)D]. In children and adolescents, the relationship between serum 25(OH)D and PTH is less clear and most studies reporting a relationship are derived from relatively small samples and homogeneous cohorts. Our objective was to determine the relationship between serum 25(OH)D and PTH in children and adolescents from a large and diverse U.S. cohort and to identify a point of inflection of serum 25(OH)D for maximal suppression of serum PTH. Data from 735 participants, ages 7-18 y, were pooled from 3 study sites located in Indiana, Texas, and Massachusetts. A two-phase linear spline was used to model the relationship between serum 25(OH)D and PTH. The value of serum 25(OH)D for maximal suppression of serum PTH was identified as the inflection point of the spline. Before adjustment for site, the inflection point of serum 25(OH)D for maximal suppression of serum PTH was 92.4 nmol/L (95% CI: 62.2, 130.7). After adjusting for site, the point of inflection was poorly defined and the relationship between serum 25(OH)D and PTH appeared to be linear. The lack of an inflection point of serum 25(OH)D for maximal suppression of PTH brings into question the value of using maximal suppression of serum PTH as a basis for determining optimal serum 25(OH)D for healthy children and adolescents.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Child; Cohort Studies; Down-Regulation; Humans; Models, Biological; Nutritional Requirements; Nutritional Status; Parathyroid Hormone; Reproducibility of Results; Statistics as Topic; United States; Vitamin D; Vitamin D Deficiency

The objective of the present study was to determine the factors associated with low concentrations of 25-hydroxy vitamin D (vitamin D deficiency) in healthy children in Qatar.. The survey was a cross-sectional study conducted at the Primary Health Care Clinics over the period from August 2007 to March 2008. Subjects The study was carried out among healthy Qatari nationals, male and female, aged below 16 years. A random sample of 650 healthy subjects who visited the Primary Health Care Centers for any reason other than acute or chronic disease were approached and 458 subjects gave consent; a response rate of 70.5%.. Face-to-face interviews were based on a questionnaire that included variables such as socio-demographic information, assessment of non-dietary covariates, assessment of dietary intake, vitamin D intake, type of feeding, clinical manifestations and laboratory investigations. The subjects' health status was assessed by medical conditions, family history, body mass index, past or present clinical manifestations, 25-hydroxy vitamin D, calcium, alkaline phosphates, phosphorus, HbA1C, Parathyroid Hormone (PTH), magnesium and creatinine analysis.. The study revealed that vitamin D deficiency was highly prevalent in Qatari adolescents (11-16 years old; 61.6%), followed by the 5-10 year olds (28.9%) and those below 5 years old (9.5%). Vitamin D deficiency increased with age and there was a significant difference between vitamin D-deficient and normal children in their age groups (P =0.013). The body mass index was significantly lower in vitamin D-deficient children (19.6+/-3.6; P =0.019). A family history of vitamin D deficiency was more frequent in children with vitamin D deficiency (33.7%) than in normal children (24.5%). Most of the vitamin D-deficient children had no physical activity (60.6%) and no exposure to sunlight (57.5%). There was a significant difference between both groups in terms of family history of vitamin D deficiency, physical activity, exposure to sunlight and duration of time spent outside under the sun (P <0.05). The mean values of vitamin D serum concentration, calcium, alkaline phosphates, and phosphorus were very low in vitamin D-deficient children. Vitamin D-deficient children had a very poor diet for vitamin D (cod liver oil, 56.5%; milk fortified with vitamin D, 27.3%; fortified food, 24.1%; and seafood, 5.7%) compared with normal children. Fractures (P =0.006), delayed milestones (P =0.013), rickets (P =0.017) and gastroenteritis (P =0.020) were significantly higher in vitamin D-deficient children.. The study findings revealed that Qatari children are at high risk for vitamin D deficiency. Lack of exposure to sunlight, outdoor activities under the sun, and physical activity and vitamin D intake are the main associated factors for vitamin D deficiency in the young population of Qatar. Breast-fed infants need to take vitamin D supplements for a longer period.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Aging; Calcifediol; Child; Child, Preschool; Cross-Sectional Studies; Diet; Environmental Exposure; Family Health; Female; Health Status; Humans; Infant; Male; Motor Activity; Nutritional Status; Prevalence; Qatar; Socioeconomic Factors; Sunlight; Time Factors; Vitamin D; Vitamin D Deficiency

Vitamin D has a wide variety of physiological functions in the human body. There is increasing evidence that low serum levels of this vitamin have an important role in the pathogenesis of different skeletal and extra-skeletal diseases. Vitamin D deficiency and insufficiency is common at northern latitudes. There are few population-based studies in the northern European region looking at the issue in a wider age group. We aimed to measure Vitamin D level in the general population of Estonia (latitude 59 degrees N), a North-European country where dairy products are not fortified with vitamin D.. The study subjects were a population-based random selection of 367 individuals (200 women and 167 men, mean age 48.9 +/- 12.2 years, range 25-70 years) from the registers of general health care providers. 25-(OH) vitamin D (25(OH)D) level and parathyroid hormone (PTH) were measured in summer and in winter. Additionally age, sex, body mass index (BMI) and self-reported sunbathing habits were recorded.. The mean serum 25(OH)D concentration in winter was 43.7 +/- 15 nmol/L and in summer 59.3 +/- 18 nmol/L (p < 0.0001). In winter 73% of the subjects had 25(OH)D insufficiency (25(OH)D concentration below 50 nmol/L) and 8% had deficiency (25(OH)D below 25 nmol/L). The corresponding percentages in summer were 29% for insufficiency and less than 1% for deficiency. PTH reached a plateau at around 80 nmol/L. BMI and age were inversely associated with 25(OH)D, but lost significance when adjusted for sunbathing habits. A difference in the seasonal 25(OH)D amplitude between genders (p = 0.01) was revealed.. Vitamin D insufficiency is highly prevalent throughout the year in a population without vitamin D dairy fortification living at the latitude of 59 degrees N.

Topics: 25-Hydroxyvitamin D 2; Adult; Age Distribution; Aged; Blood Chemical Analysis; Cross-Sectional Studies; Estonia; Europe; Female; Humans; Incidence; Male; Middle Aged; Multivariate Analysis; Probability; Regression Analysis; Risk Assessment; Seasons; Sex Distribution; Vitamin D Deficiency

The prevalence of vitamin D insufficiency and secondary hyperparathyroidism is high among morbidly obese subjects. Further, low serum levels of 25-hydroxyvitamin D (25 [OH]D) and magnesium have been associated with increased risk of the metabolic syndrome (MS), and recently, a possible link between PTH and MS has been reported. Although it is well known that the synthesis and secretion of PTH is regulated by serum levels of calcium, phosphate, magnesium and 25(OH)D, less is known about the possible clustered affiliation of these parameters with MS. We aimed to explore whether MS is associated with abnormal serum levels of PTH, 25(OH)D and magnesium in a population of morbidly obese patients.. Fasting serum levels of 25(OH)D, PTH and magnesium were assessed in a cross-sectional cohort study of 1,017 consecutive morbidly obese patients (68% women). Multiple logistic regression analyses were used to assess the independent effect of PTH, 25(OH)D and magnesium on the odds for MS (National Cholesterol Education Program [NCEP]) after adjustment for confounding factors.. Sixty-eight percent of the patients had MS. Patients with MS had lower mean serum magnesium (P < 0.001) and higher mean PTH (P = 0.067) than patients without MS, whereas mean 25(OH)D did not differ significantly. Patients with PTH levels in the second to fourth quartiles had higher odds of prevalent MS (odds ratio 1.47 [95% CI 0.92-2.35], 2.33 [95% CI 1.40-3.87] and 2.09 [95% CI 1.23-3.56], respectively), after adjustment for 25(OH)D, magnesium, calcium, phosphate, creatinine, age, gender, season of serum sampling, BMI, current smoking, albuminuria, CRP, insulin resistance and type 2 diabetes. Further, PTH was significantly correlated with systolic and diastolic pressure (both P < 0.001), but not with the other components of MS. The levels of 25(OH)D and magnesium were not associated with MS in the multivariate model.. The PTH level, but not the vitamin D level, is an independent predictor of MS in treatment seeking morbidly obese Caucasian women and men. Randomized controlled clinical trials, including different therapeutic strategies to lower PTH, e.g. calcium/vitamin D supplementation and weight reduction, are necessary to explore any cause-and-effect relationship.

Topics: 25-Hydroxyvitamin D 2; Adult; Anthropometry; Calcifediol; Calcium; Comorbidity; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Humans; Hyperparathyroidism, Secondary; Magnesium; Magnesium Deficiency; Male; Metabolic Syndrome; Middle Aged; Obesity, Morbid; Parathyroid Hormone; Phosphates; Vitamin D Deficiency; White People

Topics: 25-Hydroxyvitamin D 2; Disease Progression; Humans; Male; Prostatic Neoplasms; Risk Factors; Vitamin D Deficiency

Women with polycystic ovary syndrome (PCOS) frequently suffer from metabolic disturbances, in particular from insulin resistance. Accumulating evidence suggests that vitamin D deficiency may contribute to the development of the metabolic syndrome (MS). Hence, the aim of our study was to investigate the association of 25(OH)D levels and the components of the MS in PCOS women.. 25(OH)D levels were measured by means of ELISA in 206 women affected by PCOS. Metabolic, endocrine, and anthropometric measurements and oral glucose tolerance tests were performed.. The prevalence of insufficient 25(OH)D levels (<30 ng/ml) was 72.8% in women with PCOS. PCOS women with the MS had lower 25(OH)D levels than PCOS women without these features (17.3 vs 25.8 ng/ml respectively; P<0.05). In multivariate regression analysis including 25(OH)D, season, body mass index (BMI), and age, 25(OH)D and BMI were independent predictors of homeostatic model assessment-insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI; P<0.05 for all). In binary logistic regression analyses, 25(OH)D (OR 0.86, P=0.019) and BMI (OR 1.28, P<0.001) were independent predictors of the MS in PCOS women. We found significantly negative correlations of 25(OH)D levels with BMI, waist circumference, waist-to-hip ratio, systolic and diastolic blood pressure, fasting and stimulated glucose, area under the glucose response curve, fasting insulin, HOMA-IR, HOMA-beta, triglycerides, and quotient total cholesterol/high-density lipoprotein (HDL) and positive correlations of 25(OH)D levels with QUICKI and HDL (P<0.05 for all).. We demonstrate that low 25(OH)D levels are associated with features of the MS in PCOS women. Large intervention trials are warranted to evaluate the effect of vitamin D supplementation on metabolic disturbances in PCOS women.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Anthropometry; Blood Glucose; Body Mass Index; Cohort Studies; Diabetes Mellitus, Type 2; Female; Glucose Intolerance; Hemodynamics; Hormones; Humans; Insulin; Lipids; Metabolic Syndrome; Polycystic Ovary Syndrome; Vitamin D; Vitamin D Deficiency; Young Adult

Now emerging as an important risk factor for type 1 diabetes, vitamin D deficiency is also associated with obesity, metabolic syndrome, and type 2 diabetes and has been identified as a potential cardiometabolic risk factor. A simple, accurate screening test for 25-hydroxy vitamin D [25(OH)D] deficiency is needed. We developed a liquid chromatography/tandem mass spectrometry assay for 25-hydroxy vitamin D(2) [25(OH)D(2)] and 25-hydroxy vitamin D(3) [25(OH)D(3)] in dried blood spots.. Blood spots were collected by finger stick simultaneously with serum samples obtained by venipuncture from healthy volunteers. Disks punched from the dried blood spots were sonicated with an internal standard solution of deuterated 25(OH)D(3) (26,26,26,27,27,27-d(6)). Methanol was added to precipitate proteins prior to extraction with hexane. The extracted samples were dried and reconstituted in 50:50 methanol:H(2)O before injection into a Varian 320-MS TQ mass spectrometer.. BLOOD SPOT ASSAY PRECISION WAS GOOD OVER THE REPORTABLE RANGE: interassay coefficients of variation were 13, 13, and 11% at concentrations of 14, 26, and 81 ng/ml, respectively, for 25-hydroxy vitamin D(3) and 12% at 23 ng/ml for 25(OH)D(2). The 25(OH)D(3) assay was linear from 3.5 to 75 ng/ml (R > 0.99). Blood spot and serum values showed excellent correlation for 25(OH)D(2) (R=0.90, n=54) and 25(OH)D(3) (R=0.91, n=83).. This blood spot assay for 25(OH)D(2) and 25(OH)D(3) provides a convenient and cost-effective alternative to serum assays and can be automated. This may be valuable in large-scale screening for risk of type 1 diabetes, for cardiometabolic risk screening, and for monitoring vitamin D supplementation.

Topics: 25-Hydroxyvitamin D 2; Calcifediol; Chromatography, Liquid; Diabetes Mellitus; Hematologic Tests; Humans; Mass Screening; Metabolic Syndrome; Risk Factors; Sensitivity and Specificity; Tandem Mass Spectrometry; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Alkaline Phosphatase; Biomarkers; Calcium; Female; Gastric Bypass; Humans; Hyperparathyroidism, Secondary; Laparoscopy; Obesity; Postoperative Care; Vitamin D; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Calcitriol; Humans; Mortality; Renal Dialysis; Renal Insufficiency; Vitamin D Deficiency

The aim of this study was to describe vitamin D status in children with intractable epilepsy prescribed newer antiepileptic drugs (AEDs) before initiation of and during 15-month treatment with the ketogenic diet (KD).. Serum vitamin D (25-OHD and 1,25-OHD) and parathyroid hormone (PTH) were assessed in prepubertal children with intractable epilepsy before initiation of and during KD therapy. Three-day weighed dietary records including KD and vitamin and mineral supplementation were obtained at baseline and at 1 month.. Forty-five children (aged 5.1 +/- 2.7 years) were enrolled. Before KD therapy, 4% had deficient and 51% had insufficient serum 25-OHD levels. Vitamin D intake was less than recommended in 47%. Adequate vitamin D intake, fewer AEDs, and generalized seizures were associated with higher serum 25-OHD levels (p < 0.01). After 3 months on the KD, 25-OHD levels increased (p < 0.001), and PTH declined (p < 0.001). Over the next 12-month period, 25-OHD levels steadily declined (p < 0.001), and PTH did not significantly change.. Children with intractable epilepsy treated with newer AEDs had poor vitamin D status. Their status improved over the first 3 months of KD therapy with vitamin D supplementation and slowly declined thereafter.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Anticonvulsants; Child; Child, Preschool; Dietary Fats; Dietary Supplements; Epilepsy; Female; Humans; Infant; Ketosis; Longitudinal Studies; Male; Nutritional Status; Parathyroid Hormone; Seasons; Vitamin D; Vitamin D Deficiency

An automated application of Immunodiagnostic Systems Limited (IDS) OCTEIA 25-hydroxyvitamin D [25(OH)D] enzyme immunoassay was developed for analyses of 25(OH)D in more than 7000 participants of the 1958 cohort. Variation between 25(OH)D assays hampers between-study comparisons and the definition of relevant cutoffs for hypovitaminosis D.. The objective of the study was to evaluate the importance of assay variation on the estimated prevalence of hypovitaminosis D and assess the use of statistical harmonization to overcome the observed differences.. Agreement analyses were performed between two commercial 25(OH)D assays (IDS enzyme immunoassay and Diasorin RIA), with validation using performance data from Vitamin D External Quality Assessment Scheme (DEQAS).. The study was conducted in England, Scotland, and Wales.. Members of the 1958 British birth cohort participated in the study.. 25(OH)D was measured both by IDS and Diasorin RIA in 781 samples. Additional quality control data were obtained through participation in DEQAS (five distributions throughout the survey).. Average 25(OH)D concentrations by IDS were -15.7 and -13.7 nmol/liter lower, compared with Diasorin or DEQAS mean, respectively (both P < 0.0001). Graphical examination demonstrated a dose-related bias between IDS with Diasorin and DEQAS mean, but log transformation removed the bias. After using the log difference between the measurements as an adjustment factor, there were no differences in average 25(OH)D concentrations (P >or= 0.21 for comparison of IDS with Diasorin or DEQAS) and estimates for hypovitaminosis D obtained by IDS were similar to Diasorin.. Differences between assays have implications for public health messages about hypovitaminosis D. Harmonization of results with DEQAS enabled the use of previously determined cutoffs for hypovitaminosis D.

Topics: 25-Hydroxyvitamin D 2; Adult; Autoanalysis; Calcifediol; Cohort Studies; Data Collection; Data Interpretation, Statistical; Humans; Immunoenzyme Techniques; Middle Aged; Population; Reference Standards; Reproducibility of Results; United Kingdom; Vitamin D Deficiency

Hypovitaminosis D is well known in different populations, but may be under diagnosed in certain populations. We aim to determine the first diagnosis considered, the duration and resolution of symptoms, and the predictors of response to treatment in female asylum seekers suffering from hypovitaminosis D.. A pre- and post-intervention observational study.. A network comprising an academic primary care centre and nurse practitioners.. Consecutive records of 33 female asylum seekers with complaints compatible with osteomalacia and with hypovitaminosis D (serum 25-(OH) vitamin D < 21 nmol/l). Treatment intervention: The patients received either two doses of 300,000 IU intramuscular cholecalciferol as well as 800 IU of cholecalciferol with 1000 mg of calcium orally, or the oral treatment only.. We recorded the first diagnosis made by the physicians before the correct diagnosis of hypovitaminosis D, the duration of symptoms before diagnosis, the responders and non-responders to treatment, the duration of symptoms after treatment, and the number of medical visits and analgesic drugs prescribed 6 months before and 6 months after diagnosis.. Two-sample t-tests, chi-squared tests, and logistic regression analyses were performed. Analyses were performed using SPSS 10.0.. Prior to the discovery of hypovitaminosis D, diagnoses related to somatisation were evoked in 30 patients (90.9%). The mean duration of symptoms before diagnosis was 2.53 years (SD 3.20). Twenty-two patients (66.7%) responded completely to treatment; the remaining patients were considered to be non-responders. After treatment was initiated, the responders' symptoms disappeared completely after 2.84 months. The mean number of emergency medical visits fell from 0.88 (SD 1.08) six months before diagnosis to 0.39 (SD 0.83) after (P = 0.027). The mean number of analgesic drugs that were prescribed also decreased from 1.67 (SD 1.5) to 0.85 (SD 1) (P = 0.001).. Hypovitaminosis D in female asylum seekers may remain undiagnosed, with a prolonged duration of chronic symptoms. The potential pitfall is a diagnosis of somatisation. Treatment leads to a rapid resolution of symptoms, a reduction in the use of medical services, and the prescription of analgesic drugs in this vulnerable population.

Topics: 25-Hydroxyvitamin D 2; Administration, Oral; Adult; Analgesics; Calcium; Chi-Square Distribution; Cholecalciferol; Drug Prescriptions; Emergencies; Female; Humans; Injections, Intramuscular; Logistic Models; Osteomalacia; Pain; Primary Health Care; Prospective Studies; Radioimmunoassay; Spectrophotometry; Time Factors; Vitamin D Deficiency

Serum levels of 25-hydroxyvitamin D are important in establishing true vitamin D levels in humans. The purposes of this study were to develop a sensitive, specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection of 25-hydroxyvitamin D(2) and D(3) and establish reference intervals for these analytes. Chromatographic separation of 25(OH)D(2) and 25(OH)D(3) was achieved after adding deuterated Delta(9)-tetrahydrocannabinol (D(9)-THC-D(3)) and organic extraction. The 3 ions were ionized using positive electrospray ionization and detected in the multiple-reaction monitoring mode using mass (m)/charge (z) transitions of 318.15 > 196.20 (Delta(9)-THC-D(3)), 401.15 > 365.2 (25(OH)D(3)), and 413.15 > 355.20 (25(OH)D(2)). Reference interval study results were compared with current 25(OH)D recommendations. Elution of 25(OH)D(2), 25(OH)D(3), and Delta(9)-THC-D(3) was achieved after 3.0 minutes (total run time, 6.0 minutes). Within- and between-run coefficients of variation were less than 11%. Deming regression of radioimmunoassay and LC-MS/MS methods for total 25(OH)D levels yielded a slope of 0.97 (95% confidence interval, 0.88-1.05) and y-intercept of -1.74 ng/mL. Reference intervals were less than recommended levels (D(2), 0.0-12.1; D(3), 5.5-41.4; total vitamin D, 6.0-43.5 ng/mL [0-30, 14-103, 15-109 nmol/L, respectively]) with no statistically significant differences in race, age, or sex. This LC-MS/MS method provides a rapid, accurate, sensitive, and cost-effective alternative to other methods for detection of 25(OH)D(2) and 25(OH)D(3) at nanomolar concentrations.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Calcifediol; Chromatography, High Pressure Liquid; Female; Humans; Male; Mass Spectrometry; Middle Aged; Reference Values; Reproducibility of Results; Vitamin D Deficiency

Current data on the prevalence of vitamin D deficiency in India are scarce.. We assessed the calcium-vitamin D-parathyroid hormone axis in apparently healthy children from 2 different socioeconomic backgrounds in New Delhi, India.. Clinical evaluation for evidence of vitamin D deficiency was carried out in 5137 apparently healthy schoolchildren, aged 10-18 y, attending lower (LSES) and upper (USES) socioeconomic status schools. Serum calcium, inorganic phosphorus, alkaline phosphatase, 25-hydroxyvitamin D [25(OH)D], and immunoreactive parathyroid hormone were measured in 760 children randomly selected from the larger cohort. Bone mineral density of the forearm and the calcaneum was measured in 555 children by using peripheral dual-energy X-ray absorptiometry.. Clinical evidence of vitamin D deficiency was noted in 10.8% of the children. Children in the LSES group had a significantly (P < 0.01) lower 25(OH)D concentration (10.4 +/- 0.4 ng/mL) than did those in the USES group (13.7 +/- 0.4 ng/mL). Concentrations of 25(OH)D <9 ng/mL were seen in 35.7% of the children (42.3% in LSES; 27% in USES; P < 0.01). Boys had significantly (P = 0.004) higher 25(OH)D concentrations than did girls. There was a significant negative correlation between the mean serum immunoreactive parathyroid hormone and 25(OH) D concentrations (r = -0.202, P < 0.001). Mean forearm bone mineral density was significantly (P < 0.01) higher in the USES group than in the LSES group.. A high prevalence of clinical and biochemical hypovitaminosis D exists in apparently healthy schoolchildren in northern India.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Alkaline Phosphatase; Bone Density; Calcium; Child; Female; Humans; India; Male; Parathyroid Hormone; Phosphorus; Prevalence; Vitamin D Deficiency

To determine the prevalence of hypovitaminosis D in exclusively breast-feeding infants and their mothers in a community where maternal sunshine exposure is low.. Serum levels of calcium, phosphate, alkaline phosphatase, 25-hydroxy vitamin D (25-OHD), and intact parathyroid hormone were measured in 90 unsupplemented healthy term breast-feeding Arab/South Asian infants and their mothers in summer. Maternal dietary vitamin D intake was also estimated.. The median age of infants was 6 weeks. The median serum 25-OHD concentrations in mothers (8.6 ng/mL) and infants (4.6 ng/mL) were low, and 61% of the mothers and 82% of the 78 infants tested had hypovitaminosis D (serum 25-OHD <10 ng/mL). The infants with hypovitaminosis D had elevated serum alkaline phosphatase and a tendency to higher serum intact parathyroid hormone levels. The average daily maternal vitamin D intake from commercial milk was 88 IU.. Hypovitaminosis D is common in summer in exclusively breast-feeding infants and their mothers. The results provide justification for vitamin D supplementation of breast-feeding infants and mothers in the United Arab Emirates. Low vitamin D intake probably contributed to low maternal vitamin D status.

Topics: 25-Hydroxyvitamin D 2; Alkaline Phosphatase; Breast Feeding; Calcium; Dietary Supplements; Female; Humans; Infant; Infant Food; Infant Nutrition Disorders; Nutrition Surveys; Pakistan; Parathyroid Hormone; Phosphates; Prevalence; Risk Factors; Seasons; United Arab Emirates; Vitamin D; Vitamin D Deficiency

In order to evaluate the prevalence, risk factors, and clinical consequences of hypovitaminosis D in elderly Italian women a multicenter study of 43 osteoporosis centers from all regions of Italy was carried out. Study population included 700 women aged 60-80 years in whom blood was taken for 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) measurements. All subjects were also questioned to assess the prevalence of several risk factors for hypovitaminosis D, osteoporotic fractures and activities of daily living (ADL). Values of 25OHD lower than 5 ng/ml were found in 27% of the women and lower than 12 ng/ml in 76%. 25OHD and PTH levels were negatively correlated ( r=-0.38, after logarithmic transformation of both variables). 25OHD levels significantly declined with advancing age and number of pregnancies and were positively correlated with educational level (years spent at school), dairy calcium intake, and days spent on holiday by the sea. In a multivariate model including all these variables, the only one that remained significant was the level of education. The lowest age-adjusted 25OH D levels were found in smokers or in women living in central Italy as compared with those living in northern or southern Italy. The mean (+/-SD) age-adjusted 25OH D values were significantly lower in women who sustained a hip fracture (7.1+/-2.2 versus 11.0+/-9.9). Women with low 25OHD levels (<12 ng/ml) had worse scores for ADL and mobility ADL (move outdoors, use stairs, walk at least 400 m, carry a heavy object). Vitamin D deficiency is extremely common among elderly Italian women. Women with lower educational level, living in central Italy, smokers or with lower intake of dairy products are at greater risk. Hypovitaminosis D is associated with worsening of the ability to perform activities of daily living and higher hip fracture prevalence. This finding should lead to an urgent population-based strategy to remedy this condition.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Dairy Products; Diet; Educational Status; Female; Humans; Italy; Middle Aged; Parathyroid Hormone; Prevalence; Risk Factors; Smoking; Vitamin D Deficiency

To measure bone turnover in Muslim women with vitamin D deficiency.. A cross-sectional study of a random sample of Muslim women aged 20-65 years, evaluated over a 6-month period from November 1999 to April 2000.. 146 women living in an urban community in south-western Sydney with adequate opportunities for sun exposure.. Bone turnover as measured by urinary deoxypyridinoline (DPYD) excretion rates; and vitamin D status as determined by 25-hydroxyvitamin D (25OHD) levels, serum calcium levels and parathyroid hormone (PTH) concentrations.. We analysed data on 119 Muslim women (mean [SEM] age, 46.6 [1.1] years) who met the inclusion criteria. There were 81 (68.1%) women with serum 25OHD levels < 30 nmol/L (defined as "severe" vitamin D deficiency). Fifty-five (46.2%) women had evidence of high bone turnover (urinary DPYD excretion > 6.5 nmol/mmol creatinine). The women with "severe" vitamin D deficiency had significantly higher serum PTH levels (7.3 [0.3] v 5.4 [0.5] pmol/L; P = 0.001) and higher urinary DPYD excretion (7.2 [0.3] v 5.4 [0.2] nmol/mmol creatinine; P = 0.003) than women with serum 25OHD levels > or= 30 nmol/L. No significant differences were seen in their ages, menopausal status or serum calcium and phosphate measurements. The risk of developing high bone turnover was significantly greater in the women with "severe" vitamin D deficiency (relative risk = 5.52; 95% CI, 2-14.8; chi(2 )= 12.95; P = 0.0003).. High bone turnover occurs in Muslim women with vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Alkaline Phosphatase; Amino Acids; Bone and Bones; Calcium; Clothing; Cross-Sectional Studies; Female; Humans; Islam; Middle Aged; New South Wales; Phosphates; Reference Values; Urban Population; Vitamin D Deficiency

Chronic diseases in children may determine limited sun exposure, use of drugs, and other risk factors of osteopenia.. To evaluate vitamin D deficiency and their risk factor, in children with chronic diseases with suspected osteopenia.. We measured bone mineral density, bone remodeling markers, calcium, phosphate, parathormone, and 25 hydroxyvitamin D levels, and wrist X-ray.. We found 8 children of 25 with suspected osteopenia, with biochemical abnormalities suggestive of vitamin D deficiency. All children had low levels of 25 hydroxyvitamin D, 5 had reduced bone mineral density, 4 had hyperparathyroidism, 2 had hyperphosphatasemia, and 1 hypocalcemia and hypophosphatemia. None had rickets.. Osteopenia in chronic sick children is due to multiple factors; however, vitamin D deficiency is a preventable disorder. We recommend that all children with a chronic disease with risk factors for vitamin D deficiency should be monitored with 25 hydroxyvitamin D serum levels.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Bone Diseases, Metabolic; Child; Child, Preschool; Chile; Chronic Disease; Female; Humans; Male; Risk Factors; Vitamin D Deficiency

To study the effect of vitamin D supplementation and the impact of summer season on serum 25-hydroxyvitamin D (S-25(OH)D) in Finnish 9-15-y-old girls.. Three-year follow-up study with vitamin D(2) supplementation using D(2) 10 microg daily from October to January for the first and from October to February for the second winter as well as 20 microg daily from October to March for the third winter.. Paavo Nurmi Centre, University of Turku, Turku, Finland.. A total of 171 female volunteers aged 9-15 y.. Vitamin D and calcium intakes were estimated by a semi-quantitative food frequency questionnaire (FFQ). S-25(OH)D was measured by radioimmunoassay.. The median daily dietary intakes of vitamin D and calcium were 3.8 microg (interquartile range (IQR) 2.7-5.0) and 1451 mg (IQR 1196-1812), respectively, over 3 y. The prevalence of severe hypovitaminosis D (S-25(OH)D<20 nmol/l) was 14% and of moderate hypovitaminosis D (20 nmol/l < or = S-25(OH)D < or = 37.5 nmol/l) 75% at baseline in winter. None of the participants had severe hypovitaminosis D in summer. The effect of 10 microg of D(2) daily was insufficient to raise S-25(OH)D from baseline. The daily supplementation of 20 microg of D(2) increased S-25(OH)D significantly in wintertime compared with the non-supplement users (to 45.5 vs 31.8 nmol/l; P<0.001). None of the subjects with vitamin D(2) supplementation approximately 20 microg daily had severe hypovitaminosis D; however, 38% of those participants had moderate hypovitaminosis D at 36 months. Sun exposure in summer raised mean S-25(OH)D to 62.0 nmol/l. Both the daily supplementation of approximately 20 microg of D(2) and summer sunlight exposure had more effect on those who had severe hypovitaminosis than those who had a normal vitamin D status (increase of 24.2 vs 0.9 nmol/l (P<0.001), and 38.8 vs 18.2 nmol/l (P<0.001), respectively).. Vitamin D supplementation daily with 20 microg is needed to prevent hypovitaminosis D in peripubertal Finnish girls in winter. Sunlight exposure in summer is more effective than approximately 20 microg of D(2) supplementation daily in winter to raise S-25(OH)D. Both the daily supplementation with 20 microg of D(2) and summertime sunlight exposure had more effect on those who had severe hypovitaminosis D than those who had a normal vitamin D status.. Supported by the Yrjö Jahnsson Foundation and the Medical Research Foundation of the Turku University Central Hospital.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Calcium, Dietary; Child; Dietary Supplements; Ergocalciferols; Female; Finland; Humans; Longitudinal Studies; Prevalence; Prospective Studies; Radioimmunoassay; Seasons; Sunlight; Surveys and Questionnaires; Vitamin D Deficiency

To study the prevalence of hypovitaminosis D [serum 25(OH)D < or = 37 nmol L-1)] in Finnish medical in- and outpatients in a cross-sectional study.. The subjects were 106 consecutive medical inpatients (57 females, 49 males with mean ages of 65 and 58 years) from the Peijas Hospital, Vantaa, Finland, and 99 ambulatory patients (48 females, 51 males with mean ages of 42 and 46 years) contacting a private outpatient centre in Helsinki, Finland. Serum 25(OH)D, vitamin D binding protein (DBP), free vitamin D index (FDI), intact PTH (iPTH), and albumin-corrected calcium were measured.. Serum 25-hydroxyvitamin D [25(OH)D] was 37 nmol L(-1) or less in 70% of female and in 61% of male inpatients and in 44% of female and in 37% of male outpatients. In the whole population, a statistically significant inverse association (P < 0.0001) was detected between iPTH and 25(OH)D levels; the iPTH concentration appeared to start increasing when 25(OH)D concentration was 50 nmol L(-1) or less. The association remained the same (P < 0.0001) when FDI was used instead of 25(OH)D in the calculations. When the sexes were analysed separately, the statistically significant association was found only in females (P < 0.0001 for iPTH versus 25(OH)D; P < 0.0001 for iPTH versus FDI) but not in males.. Hypovitaminosis D is very common amongst Finnish in- and outpatients in both sexes, causing secondary hyperparathyroidism in females. More extensive studies are warranted to elucidate the vitamin D status of the Finnish population.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Cross-Sectional Studies; Female; Finland; Humans; Inpatients; Male; Middle Aged; Outpatients; Parathyroid Hormone; Prevalence; Radioimmunoassay; Statistics, Nonparametric; Vitamin D Deficiency; Vitamin D-Binding Protein

Few studies of vitamin D nutrition in Asian populations have been conducted.. The objective was to assess 25-hydroxyvitamin D [25(OH)D] concentrations in healthy elderly Japanese women during the winter and to determine whether 25(OH)D concentrations are associated with lifestyle.. We investigated 151 women aged 66.5 +/- 6.7 y (f1.gif" BORDER="0"> +/- SD) living in a rural community in February 1999. Serum 25(OH)D and intact parathyroid hormone were measured by using HPLC and an immunoradiometric assay, respectively. Information on lifestyle factors, including sunshine exposure and the consumption of vitamin D-rich foods, was also obtained through an interview.. The mean (+/-SD) 25(OH)D concentration was 59.9 +/- 17.0 nmol/L. Vitamin D insufficiencies (<30 nmol/L) were found in 4.6% of the women, a value lower than that found in white populations. No correlation was found between age and 25(OH)D concentrations (r = 0.004, P = 0.957). The 25(OH)D concentration of subjects who consumed fish frequently (>/=4 times/wk) was 10.1 nmol/L higher (P < 0.001) than that of subjects with a moderate consumption of fish (1-3 times/wk). Additionally, those who did not consume eggs had significantly lower 25(OH)D concentrations than did those who consumed eggs >/=1 time/wk (P < 0.05).. : The nutritional status of vitamin D in Japanese populations seems to be better than that in most Western populations. Frequent fish consumption is believed to help maintain adequate concentrations of serum 25(OH)D in elderly Japanese women during the winter.

Topics: 25-Hydroxyvitamin D 2; Agaricales; Aged; Aged, 80 and over; Animals; Calcifediol; Chromatography, High Pressure Liquid; Eggs; Female; Fishes; Humans; Japan; Middle Aged; Osteoporosis, Postmenopausal; Parathyroid Hormone; Postmenopause; Premenopause; Radioimmunoassay; Rural Population; Statistics, Nonparametric; Sunlight; Vitamin D Deficiency

Bone disease is an important cause of morbidity in older patients with beta-thalassaemia major and intermedia. We studied 27 women and 23 men with beta-thalassaemia major (37) and intermedia (13) whose mean age was 32.3 +/- 9.7 years. Bone mineral density (BMD) of the lumbar spine, femoral neck and distal radius was determined by dual-energy X-ray absorbiometry (DXA). The longitudinal change in BMD over a mean of 5.6 years was determined in 19 patients. Serum 25-hydroxyvitamin D, insulin growth factor-1 (IGF-1), bone formation markers bone-alkaline phosphatase, osteocalcin and the resorption marker urinary N-telopeptide cross-linked type 1 collagen (NTx) were determined. The BsmI vitamin D receptor (VDR) gene polymorphism was analysed. Reduced BMD (Z-score < -2) was present in 89%, 62% and 73% of patients in the spine, hip and radius respectively. Vitamin D deficiency was found in 62%, decreased IGF-1 in 72% and increased urinary NTx in 84% of patients. Serum IGF-1 correlated with spine and hip BMD (r = 0.4, r = 0.39, P < 0.01 respectively), and NTx correlated with the hip BMD Z-score (r = 0.35 P < 0.05). The mean annual percentage change in spine BMD was -1.36%. Patients with the VDR BB genotype had lower spine BMD than patients with the bb genotype. In conclusion, bone loss continues in adult thalassaemia patients and is associated with increased bone resorption and decreased IGF-1. The BsmI VDR gene polymorphism is associated with osteopenia in thalassaemia.

Topics: 25-Hydroxyvitamin D 2; Adult; Alkaline Phosphatase; beta-Thalassemia; Biomarkers; Bone and Bones; Bone Density; Chi-Square Distribution; Collagen; Collagen Type I; Female; Femur Neck; Humans; Insulin-Like Growth Factor I; Longitudinal Studies; Lumbar Vertebrae; Male; Middle Aged; Minerals; Osteocalcin; Peptides; Polymorphism, Genetic; Radius; Receptors, Calcitriol; Vitamin D Deficiency

The present study aimed to investigate the prevalence and seasonal variation of hypovitaminosis D (defined as serum 25-hydroxyvitamin D level below 30 nmol/l) among healthy subjects and hospitalized patients living in central Italy. We studied 297 subjects, 131 in February 1997 and 166 in July 1997, subdivided into four groups: (a) young healthy blood donors; (b) healthy postmenopausal women; (c) inpatients with various medical diseases and (d) inpatients engaged in long-term rehabilitation programmes because of various neurological disorders. In all subjects and patients serum levels of 25-hydroxyvitamin D were measured by radioimmunoassay. We found a significant seasonal variation (P < 0.0001) of serum 25-hydroxyvitamin D levels, mean values being higher in summer in all groups, except in patients with a longer hospitalization time (group (d)). In each group, a significantly higher prevalence of hypovitaminosis D was found in winter compared with summer time (P < 0.001), being unexpectedly high in postmenopausal women (winter 32% and summer 4.5%); furthermore, in both seasons, inpatients were characterized by the highest incidences of hypovitaminosis, particularly those in group (d) (winter 82.3% and summer 57.8%). The results of the present study emphasize the importance of 25-hydroxyvitamin D measurement, and the need to increase vitamin D intake in Italy; foodstuff fortification and supplement use must be considered in order to prevent negative effects of vitamin D deficiency on skeletal integrity.

Topics: 25-Hydroxyvitamin D 2; Adult; Age Factors; Aged; Analysis of Variance; Female; Hospitalization; Humans; Italy; Middle Aged; Prevalence; Seasons; Vitamin D; Vitamin D Deficiency

To establish the prevalence of hypovitaminosis D among free-living postmenopausal women referred to an osteoporosis outpatient clinic in Northern Italy, we evaluated 25-hydroxyvitamin D (25(OH)D) levels in 570 postmenopausal women who had been consecutively referred to our clinic in the 12 months beginning October 1995. Parathyroid hormone (PTH), serum calcium (Ca), creatinine (Cr) and osteocalcin (OC), urinary calcium (Ca24h) and creatinine (Cr24h), and the bone mineral density of the lumbar spine (LBMD) and femur (FBMD) were also measured. 1,25-Dihydroxyvitamin D (1,25(OH)2D) concentrations were measured in 23 women. All women had normal electrolyte serum concentrations and kidney function. Mean +/- SD 25(OH)D concentration was 18.3 +/- 8.3 ng/ml. A significant (p < 0.001) seasonal variation was seen for both 25(OH)D and PTH. Women were divided into two groups based on their vitamin D status: low vitamin D status (25(OH)D < 12 ng/ml, n = 161, 28%) and normal vitamin D status (25(OH)D > or = 12 ng/ml, n = 409, 72%). Hypovitaminosis D was found in 38.5% of all the women in the time period December-May and in 12.5% in the other half-year; among women > 70 years old 51% had hypovitaminosis D in the time period December-May and 17% in the other half-year. PTH was significantly (p < 0.05) increased, and Ca24h, OC and FBMD significantly (p < 0.05) decreased in women with hypovitaminosis D. 1,25(OH)2D positively correlated with 25(OH)D (p < 0.0001), but did not correlate with PTH, age or creatinine clearance. In conclusion, hypovitaminosis D is an important, underestimated problem in Italian free-living postmenopausal women referred to an outpatient osteoporosis clinic.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Female; Humans; Italy; Middle Aged; Postmenopause; Prevalence; Seasons; Vitamin D Deficiency

The aim of this study was to determine whether the presence of vitamin D insufficiency increases bone turnover and enhances bone loss by examining the relationship between bone turnover markers and Bone mineral density (BMD) in vitamin D insufficient and vitamin D sufficient patients, with established vertebral osteoporosis.. 119 consecutive, active, community dwelling, elderly women were assessed over a 7-month period between the months of March to October.. There was a significant correlation between parathyroid hormone (PTH) and 25 hydroxyvitamin D (25(OH)D), r = - 0. 42 (P < 0.01). The prevalence of vitamin D insufficiency was 26.9% (defined by a 25(OH)D >/= 6.1 microg/l and

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Alkaline Phosphatase; Amino Acids; Bone Density; Bone Remodeling; Calcium; Creatine; Female; Humans; Hydroxyproline; Osteocalcin; Osteoporosis; Parathyroid Hormone; Phosphates; Prevalence; Spinal Diseases; Vitamin D Deficiency

Chronically critically ill (CCI) patients are primarily elderly people who have survived a life-threatening episode of sepsis but remain profoundly debilitated and ventilator dependent. The objective of this study was to determine the prevalence of bone hyperresorption and parathyroid hormone (PTH)-vitamin D axis abnormalities in these patients.. Prevalence survey.. Respiratory care step-down unit (RCU) at a tertiary care teaching hospital.. Forty-nine ventilator-dependent CCI patients transferred from ICUs within the same institution.. None.. N-telopeptide (NTx) levels in 24-h urine collections and serum intact PTH, 25-vitamin D, and 1,25-vitamin D levels were measured within 48 h of RCU admission. Patients were hospitalized a median of 30 days before RCU admission. Four patients (9%) had normal NTx and PTH levels. Forty-five patients (92%) had elevated urine NTx levels consistent with bone hyperresorption. Nineteen patients (42% of total patients) had elevated PTH levels consistent with predominant vitamin D deficiency, 4 patients (9%) had suppressed PTH levels consistent with predominant hyperresorption from immobilization, and 22 patients (49%) had normal PTH levels consistent with an overlap of both vitamin D deficiency and immobilization. There were no differences in vitamin D metabolites among these groups.. CCI patients have a high prevalence of bone hyperresorption in which PTH levels may clarify the cause. Further studies will determine the efficacy and cost-effectiveness of routine NTx and PTH screening in these patients and the role of vitamin D and antiresorptive therapies.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Aged, 80 and over; Bed Rest; Biomarkers; Bone Resorption; Calcitriol; Chronic Disease; Collagen; Collagen Type I; Critical Illness; Female; Follow-Up Studies; Humans; Length of Stay; Male; Middle Aged; Parathyroid Hormone; Peptides; Prevalence; Prospective Studies; Respiratory Care Units; Vitamin D Deficiency

Secondary hyperparathyroidism may cause bone loss and structural deterioration of bone and may thus be a cause of fracture in the elderly. Vitamin D deficiency, renal impairment and medications are potential causes of hyperparathyroidism and may also directly predispose to fracture. We present the first findings of an ongoing study of hip fracture, vitamin D deficiency and hyperparathyroidism in a large Australian nursing home.. Descriptive prevalence study.. Two hundred and fifty-one nursing home residents were eligible for inclusion. Informed consent and successful venepuncture were obtained for 99. Residents were of median age 83 years with interquartile range (IR) 77-89 years.. 25-Hydroxyvitamin D (25OHD), intact parathyroid hormone (PTH), creatinine and biochemistry, demographic data and current medications.. Fifty-two per cent of 99 subjects had 25OHD below the reference range of 28-165 nmol/l and 96.5% were below the reference range mean. Those with low 25OHD had lower plasma calcium corrected for albumin than those with normal 25OHD (medians 2.34 vs 2.41 mmol/l, 95% confidence interval for the difference between medians (CI) -0.10 to -0.04 mmol/l, P = 0.0001) and higher PTH (medians 5.8 vs 3.9 pmol/l, CI 0.10-2.6 pmol/l, P = 0.0360). Twenty-eight per cent of 97 residents had PTH above the upper reference range limit of 6.5 pmol/l. Residents receiving frusemide had higher PTH than other residents (medians 6.95 vs 3.45 pmol/l, CI 1.9-4.2 pmol/l, P < 0.0001). In linear modelling, the most important predictor of the natural logarithm of PTH was daily frusemide dose, adjusted R2 (Ra2) = 31.8%, F = 39.3, P < 0.001. Creatinine and the reciprocal of 25OHD were other significant predictors with the final Ra2 = 39.4%, F = 17.7, P < 0.001.. Vitamin D deficiency is a common risk factor for secondary hyperparathyroidism in nursing home residents despite a climate in which vitamin D nutrition is thought to be ample. However, the daily frusemide dose is a more important predictor of PTH in this population.

Topics: 25-Hydroxyvitamin D 2; Aged; Aged, 80 and over; Australia; Calcium; Female; Furosemide; Hip Fractures; Homes for the Aged; Humans; Hyperparathyroidism, Secondary; Male; Middle Aged; Nursing Homes; Parathyroid Hormone; Risk Factors; Serum Albumin; Vitamin D Deficiency

Deprivational vitamin D deficiency began to be noted in immigrant Asians in the early 1960s. Although there have been suggestions that the level of this problem may be declining, we describe a number of clinical cases seen over a consecutive 3 1/2 year period. Musculoskeletal symptoms were the commonest though there were a variety of medical presentations requiring hospital referral. Most of the cases were Hindu vegetarians. There is likely to be significant underdiagnosis of this condition. In spite of the extensive medical, social and political attention this condition has received, our study shows that vitamin D deficiency continues to persist in certain Asians in a clinically florid fashion. An effective preventative policy is long overdue.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Age Distribution; Asia; Biopsy; Bone and Bones; Calcium; England; Female; Humans; Infant; Male; Middle Aged; Phosphates; Rickets; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Breast Feeding; Calcium, Dietary; Diet, Vegetarian; Half-Life; Humans; Rickets; Vitamin D Deficiency

Although analogs and metabolites of vitamin D have been tested for their calciotropic activity, very little information has been available concerning the effects of these compounds on gene expression. In this study one analog of vitamin D, 1,25,28-trihydroxyvitamin D2 [1,25,28-(OH)3D2], and one metabolite, 1,24,25-trihydroxyvitamin D3 [1,24,25-(OH)3D3], were tested for their effect on intestinal calbindin-D9K mRNA and protein as well as for their effect on intestinal calcium absorption and bone calcium mobilization. These compounds were also evaluated for their ability to compete for rat intestinal 1,25-(OH)2D3 receptor sites and to induce differentiation of human leukemia (HL-60) cells as indicated by reduction of nitro blue tetrazolium. In vivo studies involved intrajugular injection of 12.5 ng 1,25-(OH)2D3 or test compound to vitamin D-deficient rats and sacrifice after 18 h. 1,25,28-Trihydroxyvitamin D2 had no effect on intestinal calcium absorption, bone calcium mobilization, or intestinal calbindin-D9K protein and mRNA. Competitive binding to 1,25-(OH)2D3 receptors was 0.8% of that observed using 1,25-(OH)2D3. However, 20- and 40-fold higher doses of 1,25,28-(OH)3D2 (250 and 500 ng) resulted in significant inductions in calbindin-D9K protein and mRNA (3.5 to 7.4-fold), although doses as high as 800 ng were found to have no effect on intestinal calcium absorption or bone calcium mobilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: 25-Hydroxyvitamin D 2; Animals; Binding, Competitive; Biological Transport; Bone and Bones; Calbindins; Calcitriol; Calcium; Cell Differentiation; Dose-Response Relationship, Drug; Duodenum; Humans; Hydroxycholecalciferols; Intestinal Absorption; Male; Rats; Receptors, Calcitriol; RNA, Messenger; S100 Calcium Binding Protein G; Tumor Cells, Cultured; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Adult; Age Factors; Aged; Aging; Female; Humans; Male; Middle Aged; Netherlands; Netherlands Antilles; Tropical Climate; Vitamin D Deficiency

In 13 of 17 infants (aged 10.5 +/- 4.3; mean +/- SD mo) with iron-deficiency anemia, the serum 24,25-dihydroxyvitamin D concentration was below the normal range and in 9 of these 13 the serum 25-hydroxyvitamin D concentration was below the normal range despite the fact that these infants received 10 micrograms vitamin D/d from the age of 1 mo. The infants were treated with intramuscular iron dextran (Imferon). The iron-dextran treatment increased the hemoglobin and serum iron concentrations as well as 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D concentrations. It is known that iron deficiency impairs fat and vitamin A intestinal absorption. Therefore, it is suggested that absorption of vitamin D may also be impaired. This may contribute to the development of vitamin D deficiency. Iron supplementation may have improved the absorption of vitamin D in the small intestine and hence increased the vitamin D concentration in the plasma.

Topics: 25-Hydroxyvitamin D 2; Anemia, Hypochromic; Ergocalciferols; Humans; Infant; Israel; Prevalence; Vitamin D Deficiency

The serum levels of the active Vitamin D metabolites 25-hydroxyvitamin D[25(OH)D], 1,25-dihydroxyvitamin D[1,25(OH)2D] and 24,25 dihydroxyvitamin D [24,25(OH)2D], were studied in 21 children with Down's syndrome (DS) in Cantabria, a northern region of Spain, located at 44 degrees N latitude. Serum calcium, magnesium, phosphate, alkaline phosphatase, parathormone and osteocalcine were also determined. In the DS group, the average values of the three Vitamin D metabolites were comparable to those of an age-matched group both in winter and summer times. No child with DS showed values below the normal range, either in Vitamin D metabolites, or in the other parameters of calcium metabolism. The normal increment of 25(OH)D and 24,25(OH)2 values from March to October was not observed in five children. This anomaly was corrected in three, after adequate rules of sun exposure during summer time were followed. In the other two, the 25(OH)D levels were high throughout the study. This investigation shows that children with DS do not require Vitamin D prescription when appropriate periods of sunlight exposure are provided.

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D 2; Calcitriol; Child; Child, Preschool; Cross-Cultural Comparison; Down Syndrome; Female; Humans; Male; Reference Values; Spain; Sunlight; Vitamin D; Vitamin D Deficiency

To compare the vitamin D metabolite and nutritional status of institutionalized elderly males with a noninstitutionalized control group.. Case-control study.. Veterans Administration Medical Center Nursing Home (NH) in Richmond, Virginia.. Fifty-seven consecutive nursing home subjects were screened. After excluding blacks, those receiving anticonvulsants, glucocorticoids, or vitamin supplements, and those with liver or renal failure (creatinine greater than 1.5 mg/dL), 35 subjects were enrolled, and 22 completed the study. The noninstitutionalized control group (n = 18) consisted of consecutive volunteers, meeting the above criteria, from either a senior citizen group or a geriatric clinic.. The serum 25-hydroxy-vitamin D level in the NH residents was significantly lower than in community dwellers (17.4 +/- 5.2 ng/mL vs 31.2 pg/mL +/- 8.0 ng/mL, P less than 0.0001). No significant difference was demonstrated in 1,25-dihydroxyvitamin D levels (36.5 pg/mL +/- 10.5 in NH residents vs 42.0 pg/mL +/- 11.1 in controls). In the NH group PTH levels were inversely correlated with 25 OHD levels (P less than 0.008) and positively correlated with length of stay in the NH (P less than 0.016). There was no significant seasonal variation in vitamin D metabolite levels in the NH group. In the NH patients, the mean dietary intake of vitamin D was 232 +/- 378 mg/day and of calories was 1811 +/- 447 kcal/day.. Despite apparently adequate calories, calcium, and vitamin D intake, hypovitaminosis D with compensatory PTH elevations occurs, regardless of season, in the nursing home population.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcitriol; Calcium; Calcium, Dietary; Case-Control Studies; Energy Intake; Hospitals, Veterans; Humans; Hyperparathyroidism, Secondary; Length of Stay; Male; Middle Aged; Nursing Homes; Nutrition Surveys; Nutritional Requirements; Nutritional Status; Parathyroid Hormone; Phosphorus; Seasons; Serum Albumin; Sunlight; Virginia; Vitamin D; Vitamin D Deficiency

The vitamin D status of 53 Caucasian infants aged 10-20 mo on a macrobiotic diet and 57 matched control infants on omnivorous diets was studied. In late summer (August-November) physical symptoms of rickets were present in 28% of the macrobiotic group; these infants had lower average plasma 25(OH)D concentrations (34.0 +/- 15.3 nmol/L) (mean +/- SD) than did the macrobiotic infants without such symptoms (49.7 +/- 21.9 nmol/L, p less than 0.02). Follow-up of a subsample of 25 macrobiotic infants in March-April revealed physical symptoms of rickets in 55% of the macrobiotic infants. All concentrations in blood were considerably below those in the preceding summer; the average 25(OH)D concentration was 12.3 +/- 4.3 nmol/L. Further analysis indicated that the low availability of calcium in the macrobiotic diet was an independent factor in causing the high prevalence of rickets in summer. Avoidance of milk products in combination with a high fiber intake may damage bone development in young children.

Topics: 25-Hydroxyvitamin D 2; Calcium; Diet, Macrobiotic; Dietary Fiber; Humans; Infant; Longitudinal Studies; Netherlands; Rickets; Vitamin D Deficiency

Ascorbic acid deficiency in guinea pigs fed a vitamin D-replete diet caused a moderate reduction of Ca level in serum and bone; 25-hydroxy-cholecalciferol or 25-hydroxyergocalciferol (25-OHD) serum concentration tended to decline; renal 25-hydroxycholecalciferol-1-hydroxylase (1-OHase) activity decreased 50%; and 25-hydroxycholecalciferol-24-hydroxylase activity increased 1.6-fold. Chromatin 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] receptor concentration in the intestinal mucosa decreased 20-30%, and the percentage of occupied receptors decreased from 12-15% to 6-8%. Receptor affinity for 1,25-(OH)2D3 did not change (Kd = 0.24-0.26 nmol/L, Kd2 = 0.06-0.10 nmol/L), but the cooperativity coefficient decreased from 1.7 to 1.4. Vitamin C deficiency potentiated effects of vitamin D deprivation and impaired a restorative action of vitamin D. It was accompanied by a marked delay in the elevation of 25-OHD concentration in serum as well as decreased 1-OHase activity in kidneys and a lower concentration of occupied 1,25-(OH)2D3 receptors in the intestinal mucosa. The data demonstrate a critical role for ascorbic acid in vitamin D metabolism and binding.

Topics: 25-Hydroxyvitamin D 2; 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Animals; Ascorbic Acid Deficiency; Bone and Bones; Calcifediol; Calcium; Guinea Pigs; Intestinal Mucosa; Kidney; Male; Receptors, Calcitriol; Receptors, Steroid; Vitamin D; Vitamin D Deficiency

Synthesis of a C-24-epimeric mixture of 25-hydroxy-[26,27-3H]vitamin D2 and a C-24-epimeric mixture of 1,25-dihydroxy-[26,27-3H]vitamin D2 by the Grignard reaction of the corresponding 25-keto-27-nor-vitamin D2 and 1 alpha-acetoxy-25-keto-27-nor-vitamin D3 with tritiated methyl magnesium bromide is described. Separation of epimers by high-performance liquid chromatography afforded pure radiolabeled vitamins of high specific activity (80 Ci/mmol). The identities and radiochemical purities of 25-hydroxy-[26,27-3H[vitamin D2 and 1,25-dihydroxy-[26,27-3H]vitamin D2 D2 were established by cochromatography with synthetic 25-hydroxyvitamin D2 or 1,25-dihydroxyvitamin D2. Biological activity of 25-hydroxy-[26,27-3H]vitamin D2 was demonstrated by its binding to the rat plasma binding protein for vitamin D compounds, and by its in vitro conversion to 1,25-dihydroxy-[26,27-3H]vitamin D2 by kidney homogenate prepared from vitamin D-deficient chickens. The biological activity of 1,25-dihydroxy-[26,27-3H]vitamin D2 was demonstrated by its binding to the chick intestinal receptor for 1,25-dihydroxyvitamin D3.

Topics: 25-Hydroxyvitamin D 2; Animals; Binding, Competitive; Ergocalciferols; In Vitro Techniques; Kidney; Protein Binding; Stereoisomerism; Tritium; Vitamin D Deficiency; Vitamin D-Binding Protein

The seasonal changes in the biochemical indices of vitamin D nutrition have been measured in elderly people with differing requirements for institutionalized care. Residents of local authority homes (LAH) showed an increase in serum 25-hydroxyvitamin D3 [25(OH)D3] between spring and autumn (means 14-17 nmol/l, P less than 0.002). No significant seasonal changes were seen in patients on long-stay wards [(GW) serum 25(OH)D3 9.5 and 9.5 nmol/l] and in day-hospital attenders [(GDH) 25 and 26.8 nmol/l]. Significant differences (P less than 0.02 to P less than 0.0001) were found between the mean serum 25(OH)D3 amongst the three groups. A significant linear relationship (r = 0.84, P = 0.036) was found between mean serum 25-hydroxyvitamin D2[25(OH)D2] and dietary vitamin D2. The intake of vitamin D was suboptimal in all groups. The incidence of 25-hydroxyvitamin D deficiency [25(OH)D less than 12.5 nmol/l] varied from 11.7% of residents in LAH in autumn to 47% of GW patients in spring; but hypocalcaemia occurred less often (LAH 1.3% in autumn, GW 4.7% in spring). The diet assumes a greater role in protecting against vitamin D deficiency when the total 25(OH)D is low. Because most diets contain insufficient amounts of vitamin D, elderly institutionalized people will remain at high risk of developing vitamin D deficiency unless specific preventative measures are adopted.

Topics: 25-Hydroxyvitamin D 2; Aged; Calcifediol; Calcium; Cholecalciferol; Diet; Ergocalciferols; Homes for the Aged; Hospitalization; Humans; Length of Stay; Middle Aged; Outpatients; Seasons; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Breast Feeding; Diet, Vegetarian; Ergocalciferols; Humans; Infant; Male; Rickets; Sunlight; Vitamin D Deficiency

3 groups of elderly people (65-80 years) were studied as regards their serum 25-hydroxyvitamin D (25-OH-D) concentrations, their dietary vitamin D intake and sunlight exposure during 1 year: group 1 (long-stay geriatric patients); group 2 (residents at an old people's home), and group 3 (elderly people living in their own homes). Young adults (30-50 years) served as controls. The 25-OH-D concentration in group 1 was significantly lower during the whole year than in any other group and the concentration in group 2 was significantly lower than in group 3 and the controls. The low 25-OH-D level in the long-stay geriatric patients and in the residents at the old people's home is a consequence of both a low dietary vitamin D intake and a low exposure to sunlight.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Diet; Ergocalciferols; Female; Homes for the Aged; Humans; Male; Middle Aged; Residence Characteristics; Seasons; Self Care; Sunlight; Time Factors; Vitamin D; Vitamin D Deficiency

Serum levels of the circulating form of vitamin D, 25-hydroxyvitamin D, and calcium were measured in 104 Saudis, 44 Jordanians , 17 Egyptians and 10 other subjects aged between 18 and 23 years. All subjects were male university students living in Riyadh for more than 2 years. 25-Hydroxyvitamin D levels were (mean +/- SD) 12.8 +/- 6.3, 11.0 +/- 5.8, 11.9 +/- 6.9 and 11.9 +/- 5.0 ng/ml, respectively. The percentages of subjects with serum 25-hydroxyvitamin D levels below 10 ng/ml were 35, 45, 53 and 50% for normal Saudis, Jordanians , Egyptians and others, respectively. All subjects had normal serum calcium concentrations. There was no correlation between 25-hydroxyvitamin D and serum calcium levels in the subjects investigated. This study indicates a tendency for a low vitamin D status among residents of Saudi Arabia, in spite of abundant sunlight all the year round.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Calcium; Egypt; Ergocalciferols; Humans; Jordan; Male; Saudi Arabia; Urban Population; Vitamin D Deficiency

The relationship between delayed hypersensitivity and serum levels of 25-hydroxyvitamin D were examined in sixty-three elderly people. After intracutaneous injection of five recall antigens (Candida, mumps, PPD, tricophyton and varidase) nineteen subjects showed no response (anergy), seven showed only a weak reaction (relative anergy), and thirty-seven a normal reaction. In the anergic group mean serum level of 25-hydroxyvitamin D was significantly lower than in the group with normal immunoreactivity. Five subjects with anergy and serum 25-hydroxyvitamin D below 20 nmol/l were treated with oral vitamin D or UV irradiation for two to three months, after which both the serum 25-hydroxyvitamin D levels and the delayed hypersensitivity were normalized. In a non-treated group anergy persisted in seven out of nine patients in a second skin test. We conclude that anergy in the delayed hypersensitivity skin test in humans may in some cases be due to vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Aged; Ergocalciferols; Female; Humans; Hypersensitivity, Delayed; Immunologic Deficiency Syndromes; Intradermal Tests; Macrophages; Male; Ultraviolet Therapy; Vitamin D; Vitamin D Deficiency

In a survey of 108 subjects with a history of epilepsy in a hospital for the mentally handicapped, administration of both phenobarbitone and phenytoin was associated with low serum calcium and plasma 25-hydroxyvitamin D (25-(OH)D) levels in female subjects only. Intake of phenytoin (as mg/kg body weight) in female subjects exceeded that in males by 22 per cent, whilst the intake of phenobarbitone was 37 per cent higher. The doses of phenobarbitone and phenytoin were each inversely related to plasma 25-(OH)D concentration, but anticonvulsant drug dosage did not correlate with the magnitude of the decline of plasma 25-(OH)D concentration in winter (November-February). No influence of sodium valproate was detected on serum calcium or on plasma 25-(OH)D levels. Limited exposure to ultraviolet irradiation (UVR) or oral administration of vitamin D restored plasma 25-(OH)D to normal levels and healed osteomalacia in a subject with tuberous sclerosis. In this subject, fit frequency declined in response to UVR and to a lesser extent in response to oral vitamin D, despite the attainment of similar levels of serum calcium and of plasma 25-(OH)D. Serum calcium levels in the other 108 subjects were lower in those experiencing the most frequent fits, but serum calcium could not be restored to levels found in subjects not receiving anticonvulsant drugs unless supraphysiological doses of vitamin D were given. Vitamin D deficiency in the epileptic population receiving drugs was assessed by the response of alkaline phosphatase to vitamin D administration. A consistent fall of serum alkaline phosphatase was found only if the initial level exceeded 175 per cent of the normal value established by reference to a population not receiving phenobarbitone or phenytoin. By this criterion five out of 45 subjects (11 per cent), aged nine to 36 years were vitamin D deficient.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Alkaline Phosphatase; Anticonvulsants; Calcium; Child; Epilepsy; Ergocalciferols; Female; Humans; Male; Risk; Sex Factors; Vitamin D; Vitamin D Deficiency

1. The response to exogenous parathyroid hormone (PTH) was tested in normal subjects and patients with osteomalacia due to vitamin D deficiency; 200 MRC units of bovine PTH were administered intravenously. 2. The rise in plasma adenosine 3':5'-cyclic monophosphate (cyclic AMP) and the increase in urinary excretion of cyclic AMP were reduced in the patients with vitamin D deficiency. After treatment with vitamin D the responses returned to normal. 3. It is suggested that this reversible resistance is due to the secondary hyperparathyroidism associated with vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Calcium; Creatine; Cyclic AMP; Ergocalciferols; Female; Humans; Kidney; Male; Middle Aged; Parathyroid Hormone; Stimulation, Chemical; Vitamin D Deficiency

Using the Haddad modified method, 25-OH-D were measured in the blood of the umbilical cord of 29 infants and in peripheral serum after 6 weeks. 16 infants were given a daily dosage of 1000 I. E., 13 infants 500 I. E. vitamin D against rickets. Further they were fed with an adapted milk containing 400 I. E. vitamin D/1. The mean cord serum values were 13 and 15 ng/ml. After treatment with 1000 I. E., 25-OH-D values around 54 ng/ml were measured after 6 weeks and under 500 I. E. daily, values of 37 ng/ml, respectively. Treatment using a dosage of 500 I. E. vitamin D combined with feeding with vitamin D fortified milk seems adequate, to prevent vitamin D depletion.

Topics: 25-Hydroxyvitamin D 2; Cholecalciferol; Dose-Response Relationship, Drug; Ergocalciferols; Humans; Infant, Newborn; Infant, Newborn, Diseases; Rickets; Vitamin D Deficiency

Vitamin D-deficient pigs, rats and chicks were repleted with four daily oral doses of crystalline ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3) containing equal concentrations of each. At 24 h after the last dose, the plasma of each species was analysed for vitamin D and 25-hydroxyvitamin D by standard methods. The mean (+/- S.D.) ratios of plasma cholecalciferol to ergocalciferol concentration were 1.5 +/- 0.1 (pig). 1.7 +/- 0.1 (rat) and 6.3 +/- 1.2 (chick). The mean ratios of plasma 25-hydroxycholecalciferol to 25-hydroxyergocalciferol concentration were 4.0 +/- 0.1 (pig), 0.4 +/- 0.02 (rat) and 10.7 +/- 3.4 (chick). The mean plasma cholecalciferol/ergocalciferol ratios for the 24,25-dihydroxy-, 25,26-dihydroxy- and 1,25-dihydroxy-derivatives in the pig were 2.6 +/- 0.6, 5.8 +/- 1.3 and 5.8 +/- 0.8 respectively. This is the first evidence that mammals other than the New World monkey, like birds, discriminate between ergocalciferol and cholecalciferol. These data, therefore, suggest that species discrimination between the different forms of vitamin D is probably a general phenomenon in mammals. Moreover, this is the first indication of a species (rat) that discriminates against a cholecalciferol metabolite in favour of an ergocalciferol metabolite. Species discrimination against particular forms of vitamin D may be important to the choice of experimental animal models for studying the regulation of vitamin D metabolism and may also be an important consideration in dietary vitamin supplementation.

Topics: 25-Hydroxyvitamin D 2; Animals; Chickens; Cholecalciferol; Ergocalciferols; Rats; Species Specificity; Swine; Vitamin D; Vitamin D Deficiency

Twenty-nine patients with chronic liver disease, nine of whom had symptoms suggesting bone disease, were studied by bone histology. Nine had osteomalacia; six associated with cholestatic liver disease and three with primarily hepatocellular disease. Two of these had clinical and biochemical features of cholestasis for at least a year and the other had alcoholic cirrhosis associated with severe malnutrition. Excluding the latter patient, histological osteomalacia was significantly associated with presence and duration of cholestasis. Plasma 25-hydroxyvitamin D was low and fasting urine hydroxyproline/creatinine ratio was high in all patients with osteomalacia but were abnormal also in some patients who did not have histological osteomalacia. Serum calcium, phosphate, alkaline phosphatase, vitamin D-binding protein and radiology were unhelpful in many patients with osteomalacia. Vitamin D-deficiency correlated significantly with deficiency of other fat-soluble vitamins and those patients with rachitic levels of plasma 25-hydroxyvitamin D showed no seasonal variation, suggesting a combination of malabsorption of vitamin D and reduced sunlight exposure. We suggest that patients with chronic liver disease with cholestasis for at least a year are at risk from osteomalacia and that those likely to have this complication may be identified by plasma 25-hydroxyvitamin D and/or fasting urine hydroxyproline/creatinine ratio measurements. The diagnosis can only be made with certainty by bone biopsy.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Cholestasis; Chronic Disease; Ergocalciferols; Humans; Liver Diseases; Middle Aged; Osteomalacia; Risk; Seasons; Vitamin D Deficiency

The Asian community of Rochdale was examined for evidence of vitamin D deficiency in 1970 and again in 1980. There has been a striking improvement in the biochemical markers of vitamin D deficiency among Asian children, but little improvement was observed in the adults. Asian children born in the United Kingdom had higher serum 25 hydroxyvitamin D concentrations than migrant children. Prolonged residence in the United Kingdom and a long period of exposure to western customs was not associated with a better vitamin D status in the adults. The vitamin D status of this community was still markedly inferior to that of a white control group despite attempts to influence their dietary practices and habitual solar exposure. Vitamin D deficiency presents a continuing problem among first generation adult migrants, but a decreasing problem among children.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Alkaline Phosphatase; Asia; Body Height; Calcium; Child; Child, Preschool; Diet; England; Ergocalciferols; Female; Humans; Male; Middle Aged; Phosphorus; Sunlight; Time Factors; Vitamin D Deficiency

1. The exposure of Asian immigrants to effective quantities of naturally occurring ultraviolet light was investigated by observing the increase in serum 25-hydroxyvitamin D concentrations during the summer months. 2. The seasonal increase in adult males was greater than in adult females. 3. There was a significant positive correlation between the seasonal increase and the prevailing 25-hydroxyvitamin D concentration, compatible with the view that the accumulation of inadequate stores of 25-hydroxyvitamin D during the summer results in the low serum concentrations seen in Asian immigrants.

Topics: 25-Hydroxyvitamin D 2; Adult; Asia; Child; England; Ergocalciferols; Female; Humans; Male; Seasons; Vitamin D Deficiency

The prevalence of vitamin D deficiency in Crohn's disease and the relationship of vitamin D status to metabolic bone disease have not been fully characterized. Serum 25-hydroxyvitamin D was measured in 82 patients with Crohn's disease; 65% of Crohn's disease patients had a low serum 25-hydroxyvitamin D concentration; 25% had deficient levels (less than 10 ng/ml). The lowest 25-hydroxyvitamin D levels were observed in patients with previous ileal resections. Nine patients were studied in detail including transiliac needle bone biopsies; 6 had osteomalacia and 3 osteoporosis. Six patients had repeat bone biopsies 9 to 18 mo after vitamin D treatment. Three patients with osteomalacia and low serum 25-hydroxyvitamin D levels showed histologic improvement after therapy with oral vitamin D restored serum 25-hydroxyvitamin D levels to normal. The adequacy of therapy was assessed accurately by monitoring serum 25-hydroxyvitamin D concentration. Three patients with metabolic bone disease with normal serum 25-hydroxyvitamin D levels at diagnosis did not show histologic improvement after receiving vitamin D.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Bone and Bones; Bone Diseases, Metabolic; Crohn Disease; Ergocalciferols; Female; Humans; Male; Middle Aged; Osteomalacia; Vitamin D; Vitamin D Deficiency

The levels of vitamin D metabolites were measured in three children with a decreased dietary intake of calcium and vitamin D and sun exposure. All three children had hypocalcemia, hypophosphatemia, and elevated alkaline phosphatase activities. Two children had rickets, aminoaciduria, and elevated immunoreactive parathyroid hormone (iPTH) concentrations. The concentrations of vitamins D2 and D3, 25-hydroxyvitamins D2 and D3 (25-OH-D2 and 25-OH-D3), and 24,25-dihydroxyvitamin D (24,25-[OH]2D) were reduced. Nonetheless, the levels of calcitriol (1,25-[OH]2D) were normal. The combination of hypocalcemia, hypophosphatemia, and increased iPTH concentrations should result in supranormal calcitriol concentrations. Moreover, the ratio of PTH to calcitriol is significantly higher than in normal subjects. Accordingly, in patients with vitamin D deficiency and "normal" calcitriol values, the synthesis of this compound may be reduced. The evaluation of vitamin D deficiency should include the measurement of all metabolites.

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D 2; Adolescent; Calcifediol; Calcitriol; Child; Cholecalciferol; Dihydroxycholecalciferols; Ergocalciferols; Humans; Hydroxycholecalciferols; Parathyroid Hormone; Reference Values; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Alkaline Phosphatase; Animals; Carotenoids; Child; Child, Preschool; Ergocalciferols; Humans; Infections; Intestinal Absorption; Phytic Acid; Protein-Energy Malnutrition; Retinol-Binding Proteins; Stress, Physiological; Sunlight; Vitamin A; Vitamin A Deficiency; Vitamin D Deficiency

The effects of maternal vitamin D deprivation on rat pups were examined in terms of serum levels of Ca, phosphorus (P), and 25-hydroxyvitamin D (250HD), ash content, and histological appearance of long bones. In each of 10 experiments, litters of 8--10 young were examined at 2 or 3 different ages within the range of 5--57 days. Pregnant mothers were fed a diet containing 0.4% Ca, and 0.4% P and either no vitamin D(--D) or 5 IU D3/g diet (+D). Mothers fed the --D diet developed marked hypocalcemia (4--5 mg/dl) during lactation, but no change in milk Ca or P. The earliest changes in pups suckled by mothers on --D diets compared to pups suckled by mothers on +D diets were significant reductions at 8 days in serum P (6--12% in 3 of 5 experiments) and in serum 250HD3. By the 15th day, serum 250HD3 was undetectable, body weight was reduced by 26%, serum Ca was reduced by 9%, and serum P was reduced by 15%. During the following 10 days, when gradual weaning took place, serum Ca decreased progressively, serum P returned to normal, serum Mg became elevated, bone ash (as percent of dry weight of tibia) was decreased, and decalcified sections of the proximal end of the tibia revealed irregularity and widening (1.5- to 3-fold) of the hypertrophic cartilage layer and the metaphyseal trabeculae. All of these changes were also prominent in 8-week-old --D rats. The results indicate that rat pups suckling vitamin D-deprived mothers can develop biochemical evidence (including hypophosphatemia) as well as histological evidence of vitamin D deficiency similar to that of human vitamin D deficiency rickets. This is in contrast to rats deprived of vitamin D after weaning, who do not develop hypophosphatemia or characteristic histological evidence of rickets unless deprived of P as well as vitamin D.

Topics: 25-Hydroxyvitamin D 2; Aging; Animals; Calcium; Female; Hydroxycholecalciferols; Hypocalcemia; Lactation; Magnesium; Milk; Phosphates; Pregnancy; Rats; Rickets; Vitamin D Deficiency

Topics: 25-Hydroxyvitamin D 2; Animals; Calcitriol; Calcium; Dihydroxycholecalciferols; Hydroxycholecalciferols; Male; Parathyroid Glands; Parathyroid Hormone; Phosphates; Rats; Thyroidectomy; Vitamin D Deficiency

A simple and precise method has been developed for the determination of 25-hydroxyvitamin D in 1 ml of human plasma. The method consists of methanol/chloroform extraction, purification by high pressure liquid chromatography and a competitive protein binding assay using vitamin D deficient rat serum. The ethanol extract from vitamin D deficient chick serum was added to the sample before CPBA to eliminate the non-specific interference in the CPBA system as a vitamin D free serum extract. The assay was sensitive to 0.72 ng/ml of plasma. Satisfactory results were obtained in the dilution and recovery tests. The coefficients of variation were 5.8 approximately 9.1% for the within-assay, and 7.4 approximately 10.3% for the between-assay. Plasma concentrations of 25-hydroxyvitamin D in 46 samples of normal human plasma were 21 +/- 10.5 ng/ml (mean +/- SD), and the seasonal variation was demonstrated. Plasma levels for 25-hydroxyvitamin D were high in patients receiving vitamin D2 and low in patients suffering from liver cirrhosis.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Adult; Aged; Binding, Competitive; Calcifediol; Child; Child, Preschool; Chromatography, High Pressure Liquid; Ergocalciferols; Female; Humans; Hydroxycholecalciferols; Infant; Liver Cirrhosis; Male; Middle Aged; Protein Binding; Vitamin D Deficiency

Vitamin D appears to influence parathyroid function indirectly through its effects on calcium metabolism rather than by a direct action of its metabolites on the parathyroid glands. In states of both secondary and primary hyperparathyroidism, the quantitative production of 1,25-(OH)2D may be determined by the prevailing concentration of serum 25-(OH)D but there appears to be some constraint that limits the formation of 1,25-0(OH)2D when the provision of its precursor exceeds the physiological. From the absence of this constraint in 'type 2 vitamin D dependency' it is inferred that it may operate through 'self-inhibition' of the renal production of 1,25-(OH)2D. It is shown that the level of serum 25-(OH)D may always exert some influence on the production of 1,25-(OH)2D and that this effect is facilitated by hyperparathyroidism. In developing vitamin D deficiency the reactive secondary hyperparathyroidism may thus function as an adaptive mechanism that sustains the level of serum 1,25-(OH)2D in the face of a diminishing serum 25-(OH)D. Failure of this adaptation and the development of a critical deficiency of 1,25-(OH)2D is regarded as the direct cause of defective mineralisation of bone. This concept would explain the absence of osteomalacia in some patients with very low levels of serum 25-(OH)D and the occurrence of defective osseous mineralisation in hypoparathyroidism.

Topics: 25-Hydroxyvitamin D 2; Calcitriol; Ergocalciferols; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Hypocalcemia; Osteomalacia; Parathyroid Hormone; Vitamin D; Vitamin D Deficiency

Among the many theories put forth to explain sudden infant death syndrome (SIDS) is a theory of vitamin D deficiency. 25-Hydroxyvitamin D (25-OHD) serum concentrations were measured in 31 SIDS and 24 postmortem control infants. 25-OHD was 19.0 +/- 7.9 mg/ml in SIDS, 16.9 +/- 5.2 ng/ml in acute death control infants, and 11.9 +/- 4.4 ng/ml in in-hospital deaths. For four "near miss" infants the mean serum 25-OHD concentration was 21.1 +/- 4.1 ng/ml. The mean serum 25-OHD concentration of 39 living premature or small-for-gestational-age infants at 3 months of age was 26 +/- 9.9. Serum calcium and serum copper concentrations were also the same in SIDS and control infants. Parathyroid hormone was measured in ten and was detectable in five SIDS infants. These data eliminate a simple vitamin D deficiency or a 25-OHD deficiency as a significant contribution to the pathophysiology of SIDS.

Topics: 25-Hydroxyvitamin D 2; Calcium; Copper; Humans; Hydroxycholecalciferols; Infant; Magnesium; Parathyroid Hormone; Phosphorus; Sudden Infant Death; Vitamin D Deficiency; Zinc