vitamin-b-12 and Diabetic-Retinopathy

Previous studies have shown an association between low serum vitamin B12 levels and the risk of diabetic retinopathy (DR) in type 2 diabetes, but the conclusions from various studies were inconsistent. Therefore, we collected relevant data from various databases to perform a meta-analysis and address the inconsistencies in these studies.. We searched PubMed, Embase, Cochrane Library, CNKI, Wanfang and CQVIP for eligible studies published up to April 10, 2022, and performed a meta-analysis using Stata software to assess the association between serum vitamin B12 levels and DR.. A total of 15 studies were included in this meta-analysis. Statistical analysis showed that serum vitamin B12 levels were significantly reduced in patients with type 2 diabetic retinopathy ,WMD 95% CI = -68.91 (-76.76, -61.06) (p <0.00001, I. This meta-analysis analyzed vitamin B12 in patients with type 2 diabetic retinopathy and emphasized the importance of monitoring serum vitamin B12 levels in patients with type 2 diabetic retinopathy, but this meta-analysis still has deficiencies and limitations, and more clinical studies are needed to confirm this conclusion in the future.

Topics: Asian People; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Ethnicity; Humans; Vitamin B 12

Topics: Adrenalectomy; Amblyopia; Aminosalicylic Acids; Anticoagulants; Cataract; Clofibrate; Diabetic Retinopathy; Diet; Diplopia; Fructose; Glaucoma; Humans; Light Coagulation; Lipotropic Agents; Pituitary Gland; Retina; Rutin; Steroids; Vision Disorders; Vitamin B 12

Topics: Aneurysm; Angiography; Diabetic Retinopathy; Diathermy; Diet; Exudates and Transudates; Fluorescence; Hemorrhage; Humans; Hypophysectomy; Insulin; Light Coagulation; Retinal Vessels; Retinitis; Testosterone; Trypsin; Vitamin B 12; Vitreous Body

Topics: Corrinoids; Diabetic Angiopathies; Diabetic Retinopathy; Diet; Diet Therapy; Drug Therapy; Humans; Insulin; Nandrolone; Testosterone; Vitamin B 12

Topics: Adenosine Triphosphate; Anabolic Agents; Anticoagulants; Chondroitin; Cytochromes; Diabetic Retinopathy; Drug Therapy; Estrogens; Fructose; Geriatrics; Humans; Insulin; Nandrolone; Radiotherapy; Steroids; Surgical Procedures, Operative; Testosterone; Testosterone Congeners; Vasopressins; Vitamin B 12; Vitamin B Complex; Vitamin E

This study aimed to evaluate the effect of treatment with eye drops containing citicoline and vitamin B. In the results of follow-up evaluation, the DC and DP groups were significantly different: Significant reduction in function in terms of 10-2 FDT mean sensitivity and in morphology reflected by an increase in inner nuclear layer thickness and decrease in other plexiform layer thickness and foveal vessel density were observed in the DP group, while no such significant changes were observed in the DC group in the long term.. This pilot study indicated that patients with DM1 with mild signs of diabetic retinopathy (DR) who underwent treatment with citicoline and vitamin B. ClinicalTrials.gov identifier, NCT04009980.

Topics: Adult; Aged; Cytidine Diphosphate Choline; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Humans; Italy; Male; Middle Aged; Ophthalmic Solutions; Pilot Projects; Prospective Studies; Retina; Tomography, Optical Coherence; Visual Acuity; Vitamin B 12; Vitamins

Diabetic retinopathy (DR) is one of the most important causes of preventable visual impairment among patients of working age and leading cause of blindness. Deficiency of vitamin B12 and folate has been associated with increased serum homocysteine (Hcy) levels. This study was done to find out the role of vitamin B12 and Hyperhomocysteine (HHcy) in Diabetic retinopathy. The present study is a hospital-based case-control study conducted during over a period of 12 months from January 2019 to December 2019 study conducted in the Department of Ophthalmology at BIRDEM General Hospital, Dhaka, Bangladesh consisting of 100 Type 2 DM patients either with or without retinopathy (DR, n=50 and DNR, n=50, respectively). Subjects with Type 2 DM with and without retinopathy were recruited from patients attending in the department of Ophthalmology at BIRDEM General Hospital, Dhaka and were matched for duration of diabetes. Diabetes subjects on nutritional supplements for the last 6 months and those with a history of nephropathy (based standard renal function tests) and complications other than DR were excluded. Homocysteine (Hcy) levels were inversely related (p<0.05) with Diabetes patients with retinopathy. Vitamin B12 also significant correlated with Diabetes patients with retinopathy. A statistically significant negative linear relationship was found between serum homocysteine and vitamin B12 levels (Pearson r = -0.918, p=0.001) Diabetes patients with retinopathy. Vitamin B12 significantly correlated with diabetes retinopathy and homocysteine levels were inversely related with diabetes patients with retinopathy.

Topics: Bangladesh; Case-Control Studies; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Humans; Hyperhomocysteinemia; Vitamin B 12; Vitamin B 12 Deficiency

This study aimed to assess the role of plasma homocysteine (Hcy) in the development of nonproliferative diabetic retinopathy (NPDR) in patients with type 2 diabetes (T2DM) without chronic kidney disease.. This was a cross-sectional study that included 94 T2DM. Hcy, serum 25-hydroxy (25-OH) vitamin D, vitamin B12, and folate were determined by the CMIA method. NPDR was determined according to the EURODIAB retinal photography methodology and optical coherence tomography (OCT) of the macula.. Compared to patients without NPDR, patients with NPDR had longer diabetes duration (p < 0.001), higher Hcy (p < 0.001), lower vitamin B12 (p = 0.028) and lower estimated glomerular filtration rate (eGFR) (p = 0.004). NPDR was positively associated with diabetes duration (p < 0.001), HbA. Higher Hcy is associated with NPDR and may play a role as a risk factor for its development in T2DM. Vitamins B12 and D seem to modify this association.

Topics: Cross-Sectional Studies; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Folic Acid; Homocysteine; Humans; Vitamin B 12

Diabetic retinopathy is the most common complication in diabetic patients relates to high expression of VEGF and microaneurysms. Scutellarin (Scu) turned out to be effective against diabetes related vascular endothelial cell dysfunction. However, its clinical applications have been limited by its low bioavailability. In this study, we formulated and characterized a novel intestinal target nanoparticle carrier based on amphiphilic chitosan derivatives (Chit-DC-VB12) loaded with scutellarin to enhance its bioavailability and then evaluated its therapeutic effect in experimental diabetic retinopathy model.. Chit-DC-VB12 nanoparticles showed low toxicity toward the human colon adenocarcinoma (Caco-2) cells and zebra fish within concentration of 250 μg/ml, owing to good biocompatibility of chitosan. The scutellarin-loaded Chit-DC-VB12 nanoparticles (Chit-DC-VB12-Scu) were then prepared by self-assembly in aqueous solution. Scanning electron microscopy and dynamic light scattering analysis indicated that the Chit-DC-VB12-Scu nanoparticles were spherical particles in the sizes ranging from 150 to 250 nm. The Chit-DC-VB12-Scu nanoparticles exhibited high permeation in Caco-2 cell, indicated it could be beneficial to be absorbed in humans. We also found that Chit-DC-VB12 nanoparticles had a high cellular uptake. Bioavailability studies were performed in Sprague-Dawley rats, which present the area under the curve of scutellarin of Chit-DC-VB12-Scu was two to threefolds greater than that of free scutellarin alone. Further to assess the therapeutic efficacy of diabetic retinopathy, we showed Chit-DC-VB12-Scu down-regulated central retinal artery resistivity index and the expression of angiogenesis proteins (VEGF, VEGFR2, and vWF) of retinas in type II diabetic rats.. Chit-DC-VB12 nanoparticles loaded with scutellarin have better bioavailability and cellular uptake efficiency than Scu, while Chit-DC-VB12-Scu nanoparticles alleviated the structural disorder of intraretinal neovessels in the retina induced by diabetes, and it also inhibited the retinal neovascularization via down-regulated the expression of angiogenesis proteins. In conclusion, the Chit-DC-VB12 nanoparticles enhanced scutellarin oral delivery efficacy and exhibited potential as small intestinal target promising nano-carriers for treatment of type II diabetes induced-retinopathy.

Topics: Administration, Oral; Animals; Apigenin; Biological Availability; Caco-2 Cells; Chitosan; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Drug Carriers; Drugs, Chinese Herbal; Erigeron; Glucuronates; Humans; Male; Nanoparticles; Rats, Sprague-Dawley; Retinal Vessels; Vascular Endothelial Growth Factor A; Vitamin B 12; Zebrafish

To study the correlation between serum levels of vitamin B. In a tertiary care center-based prospective cross-sectional study, 60 consecutive cases and 20 healthy controls in the age group of 40-65 years were included. The eyes of the cases were divided into three groups according to Early Treatment Diabetic Retinopathy Study (ETDRS) classification: diabetes mellitus without retinopathy (n = 20), non-proliferative diabetic retinopathy with macular edema (n = 20), and proliferative diabetic retinopathy with macular edema (n = 20). The serum levels of vitamin B. Increased severity of diabetic retinopathy was found to correlate with an increase in the serum levels of homocysteine (F = 53.79; p<0.001). The mean serum levels of vitamin B. This study, for the first time, demonstrated a correlation between increased homocysteine with a decrease in RNFL thickness and increased severity of diabetic retinopathy.

Topics: Adult; Aged; Cross-Sectional Studies; Diabetic Retinopathy; Enzyme-Linked Immunosorbent Assay; Female; Folic Acid; Homocysteine; Humans; Male; Middle Aged; Nerve Fibers; Prospective Studies; Retinal Ganglion Cells; Tomography, Optical Coherence; Vitamin B 12

l-Methylfolate, pyridoxal 5'-phosphate, and methylcobalamin, individually have been reported to have beneficial effects on diabetes-induced defects. The possibility that combining these therapeutic approaches might have additional benefit led us to investigate the effect of Metanx against development of early stages of diabetic retinopathy in a mouse model.. C57BL/6J mice were made diabetic with streptozotocin, and some were given Metanx (a combination food product) mixed in the food at a dose of 5 mg/kg of body weight. Mice were killed at 2 months and 10 months of study for assessment of retinal function, retinal vascular histopathology, accumulation of albumin in neural retina, and biochemical and physiological abnormalities in retina.. Two months of diabetes significantly increased leukostasis within retinal vessels and superoxide generation by the retina. Diabetes also significantly increased expression of intercellular adhesion molecule-1 (ICAM-1) and phosphorylation of IκB. Daily consumption of Metanx significantly inhibited all of these abnormalities. Ten months of diabetes significantly increased the degeneration of retinal capillaries and impaired visual function (spatial frequency threshold (SFT) and a parameter of contrast sensitivity) compared to nondiabetic controls. Daily consumption of Metanx for 10 months inhibited impairment of SFT but had no significant beneficial effect on capillary degeneration, pericyte loss, or the estimate of contrast sensitivity.. Metanx inhibited a diabetes-induced defect in retinal spatial frequency threshold and inhibited measures of oxidative stress and inflammation. It had no significant effect on contrast sensitivity or retinal capillary degeneration. Nutritional management with Metanx may help inhibit diabetes-induced defects in visual function.

Topics: Animals; Contrast Sensitivity; Diabetes Mellitus, Experimental; Diabetic Retinopathy; Folic Acid; I-kappa B Proteins; Intercellular Adhesion Molecule-1; Leukostasis; Male; Mice; Mice, Inbred C57BL; Pyridoxal Phosphate; Retinal Vessels; Superoxides; Vitamin B 12; Vitamin B Complex

We investigated the association of serum homocysteine levels and vitamin status with type 2 diabetic retinopathy. This study included 65 patients with and 75 patients without diabetic retinopathy. Patients with diabetic retinopathy had significantly higher serum homocysteine levels (P < 0.001), higher prevalence of hyperhomocysteinemia (P < 0.001), lower serum folic acid (P < 0.001), and vitamin B12 (P = 0.014) levels than those without diabetic retinopathy. Regression analysis revealed that homocysteine was an independent risk factor for diabetic retinopathy and there was a threshold in its serum level (13.7  μ mol/L), above which the risk of diabetic retinopathy greatly increases (OR = 1.66, P = 0.001). Folic acid was associated with decreased odds for diabetic retinopathy (OR = 0.73, P < 0.001). There was a threshold in serum vitamin B12 level (248.4 pg/mL), below which serum homocysteine concentration significantly increases with decreasing serum vitamin B12 (P = 0.003). Our findings suggest that hyperhomocysteinemia is an independent risk factor for the development and progression of diabetic retinopathy. Decreased serum levels of folic acid and vitamin B12, through raising serum homocysteine concentrations, may also affect the diabetic retinopathy risk.

Topics: Adult; Aged; Aged, 80 and over; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Folic Acid; Homocysteine; Humans; Hyperhomocysteinemia; Male; Middle Aged; Odds Ratio; Prevalence; Regression Analysis; Risk Factors; Vitamin B 12; Vitamins

Aim of the study was to clarify the relationship between metformin-induced vitamin B12 (B12) deficiency, hyperhomocysteinemia and vascular complications in patients with type 2 diabetes. Serum B12 concentrations, homocysteine plasma levels, the presence of retinopathy and history of macroangiopathy (stroke or coronary heart disease) were analyzed in patients without renal dysfunction (serum creatinine<115 μmol/L). Firstly, B12 status was analyzed in 62 consecutive metformin-treated patients. Secondly, the relationship between B12, homocysteine and vascular complications was analyzed in 46 metformin-treated and 38 age- and sex-matched non-metformin-treated patients. Among the 62 consecutive metformin-treated patients, B12 was deficient (<150 pmol/L) in 8 (13%) and borderline-deficient (150-220 pmol/L) in 18 (29%): the larger the metformin dosage, the lower the B12 (P=0.02, Spearman's ρ=-0.30). There were independent correlations between metformin use and B12 lowering (P=0.02, r = -0.25), and B12 lowering and elevation of homocysteine (P<0.01, r=-0.34). Elevation of homocysteine was a risk for retinopathy (P=0.02, OR 1.26, 95%CI 1.04-1.52). There was no significant relation between homocysteine and macroangiopathy. Correlation between B12 and homocysteine was stronger in metformin-treated (P<0.01, r=-0.48) than non-metformin-treated (P=0.04, r=-0.38) patients. In ten B12 deficient patients, B12 supplementation (1,500 μg/day) for 2.2±1.0 months with continued use of metformin raised B12 levels: 152±42 and 299±97 pmol/L before and after treatment, respectively (P<0.01). Metformin-induced B12 lowering in diabetes was associated with elevation of homocysteine, and hyperhomocysteinemia was independently related to retinopathy. Metformin-induced B12 deficiency was correctable with B12 supplementation.

Topics: Aged; Coronary Disease; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Retinopathy; Dietary Supplements; Dose-Response Relationship, Drug; Female; Homocysteine; Humans; Hyperhomocysteinemia; Hypoglycemic Agents; Japan; Male; Metformin; Middle Aged; Prevalence; Risk Factors; Severity of Illness Index; Stroke; Vitamin B 12; Vitamin B 12 Deficiency

The aim of this study was to examine the relation between serum total homocysteine concentrations and microvascular complications in Pima Indians with Type 2 diabetes.. Homocysteine concentrations were measured in frozen sera of 396 diabetic participants in a longitudinal study who were 40 years of age or older and who had attended one or more examinations between 1982 and 1985. Retinopathy was assessed by fundoscopy and nephropathy by an albumin:creatinine ratio greater than 300 mg/g. The incidence rate ratio for a 5 micro mol/l difference in homocysteine was calculated using proportional hazard regression.. The incidence of each complication was assessed in subjects without that complication at baseline and with more than one follow-up examination: 229 for nephropathy, 212 for retinopathy and 266 for proliferative retinopathy. There were 101 incident cases of nephropathy, 113 of retinopathy and 40 of proliferative retinopathy during a mean follow-up of 8.6, 7.5 and 8.9 years, respectively. Incidence of nephropathy was associated with homocysteine concentrations: IRR=1.42 (95% CI, 1.09-1.84, p=0.01); this remained statistically significant controlled for age, sex and duration of diabetes (p=0.03), but not when controlled for baseline renal function (p=0.4). Homocysteine concentrations were not associated with the incidence of any retinopathy IRR=1.14 (95%CI 0.89-1.46, p=0.3) but were associated with the incidence of proliferative retinopathy IRR=1.62 (95% CI 1.16-2.28, p=0.005); this association remained statistically significant when controlled for baseline renal function and diabetes duration (p=0.02).. Increased homocysteine concentrations are associated with an increased risk for incidence of nephropathy and proliferative retinopathy; the relation with incidence of nephropathy seems to be explained by an association with baseline albuminuria status concentrations, whereas the relation with incidence of proliferative retinopathy does not.

Topics: Age Factors; Analysis of Variance; Arizona; Biomarkers; Blood Glucose; Creatinine; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Female; Folic Acid; Homocysteine; Humans; Incidence; Indians, North American; Longitudinal Studies; Male; Middle Aged; Vitamin B 12

Topics: Biomarkers; Blood Pressure; Creatinine; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Folic Acid; Gene Frequency; Homocysteine; Homozygote; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Oxidoreductases Acting on CH-NH Group Donors; Point Mutation; Vitamin B 12

Homocysteine is involved in a complex and dynamic system of vascular injury and repair and may thus contribute to the development of diabetic microangiopathy. This still debated issue has important scientific and clinical implications, since hyperhomocysteinemia can be corrected nutritionally.. 1) To evaluate the association between fasting plasma homocysteine, type 1 diabetes and its microvascular complications; 2) to elucidate the basis of this association by investigating the major determinants of plasma homocysteine in relation to diabetic microangiopathy.. We studied sixty-six consecutive patients with type 1 diabetes mellitus of > 10 years duration and normal serum creatinine (< 115 mumol/L, 1.3 mg/dL), and free from clinically detectable cardiovascular diseases. Forty-four non-diabetic controls were also studied. Plasma concentrations of homocysteine, folate and vitamin B12 were investigated together with the C677T mutation in the gene coding for methylenetetrahydrofolate reductase (MTHFR), a key enzyme in homocysteine metabolism. Renal and retinal diabetic complications were evaluated as albumin/creatinine ratio on early-morning, urine spot collection and fundus photographs.. Fasting plasma homocysteine levels were very similar in patients and controls. Patients with microalbuminuria or proliferative retinopathy had significantly higher values than those without: 9.4 +/- 3.1 vs 7.4 +/- 2.8 mumol/L, p < 0.02 and 9.5 +/- 2.6 vs 7.3 +/- 3.0 mumol/L, p < 0.05. This difference was not attributable to confounders, such as age, sex and smoking, nor to dissimilar plasma folate and vitamin B12 concentrations. In contrast, homozygosity for the C677T mutation in the MTHFR gene--the commonest genetic defect linked to moderately increased plasma homocysteine--was significantly more frequent in patients with microalbuminuria and/or proliferative retinopathy (50% vs 13%, p < 0.004), odds ratio 6.7 (95% CI 1.7-27.6).. Type 1 diabetes as such is not associated with increased plasma homocysteine levels, though patients with microalbuminuria and/or proliferative retinopathy display significantly higher values than those without. This difference is not attributable to obvious confounders, nor to differences in vitamin status, and may be partly mediated by genetic factors. Plasma homocysteine, together with other diabetes-related noxae, may thus be in a position to contribute to the development of nephropathy and the progression of retinopathy.

Topics: Adult; Albuminuria; Case-Control Studies; Creatinine; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Female; Folic Acid; Homocysteine; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Oxidoreductases Acting on CH-NH Group Donors; Point Mutation; Vitamin B 12

The increased cardiovascular risk in subjects with NIDDM is partly explained by an association with established risk factors like hypertension, dyslipidemia, and obesity. Mild hyperhomocysteinemia has emerged as a new risk factor for cardiovascular disease. The purpose of this study was to assess its role in NIDDM.. We studied predictors of homocysteine levels and correlations between homocysteine and (micro-)albuminuria, retinopathy, and history of cardiovascular disease in normotensive NIDDM subjects under stable metabolic control. This was done in 85 NIDDM subjects by measuring fasting and post-methionine-loading homocysteine levels together with blood pressure, BMI, serum cholesterol, triglyceride, HDL cholesterol, folate, vitamin B12, pyridoxal-5-phosphate, HbA1c, and (micro-)albuminuria and creatinine clearance in triplicate 24-h urine samples. The relationship between micro- and macrovascular complications and fasting homocysteine only was studied in an additional 65 subjects, giving a total of 150 subjects.. In multiple regression analysis, significant (P < 0.05) predictors of fasting homocysteine were low-normal values of creatinine clearance (threshold effect at < 80 ml.min-1 .1.73 m-2), folate (< 20 nmol/l), and vitamin B12 (< 350 pmol/l), and postmenopausal status in women. Determinants of post-methionine homocysteine were pyridoxal-5-phosphate levels < 80 nmol/l, creatinine clearance, and sex (higher levels in women). Hyperhomocysteinemia did not cluster with other cardiovascular risk factors, like hypertension, obesity, or dyslipidemia. Regarding cardiovascular complications, fasting homocysteine, but not post-methionine homocysteine, was higher in subjects with a history of cardiovascular disease. There was a stepwise increase in the prevalence of subjects with cardiovascular disease with increasing fasting homocysteine. The prevalence of cardiovascular disease was 19.4% in the bottom quartile of fasting homocysteine, versus 55.0% in the top quartile (P for trend < 0.01). Neither fasting homocysteine nor post-methionine homocysteine correlated with (micro-)albuminuria or with retinopathy.. The findings suggest that homocysteine levels in NIDDM rise even with modest deterioration of renal function and when vitamin status is in the low to low-normal range. Fasting homocysteine correlates with macrovascular disease, but we found no evidence of a correlation with retinopathy or (micro-)albuminuria. Post-methionine homocysteine levels do not show a correlation with micro- or macrovascular complications.

Topics: Administration, Oral; Adult; Aged; Albuminuria; Analysis of Variance; Blood Pressure; Cardiovascular Diseases; Creatinine; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Retinopathy; Fasting; Female; Folic Acid; Homocysteine; Humans; Male; Methionine; Middle Aged; Postmenopause; Premenopause; Pyridoxal Phosphate; Regression Analysis; Risk Factors; Vitamin B 12

In a previous study, we showed that diabetic patients exhibited significantly increased concentrations of total plasma homocysteine (tHcy), but not until the onset of nephropathy. It was suggested that the hyperhomocysteinaemia might contribute to the accelerated atherosclerotic process in diabetic patients. In the present study, we have analysed the main determinants of plasma homocysteine (i.e. serum cobalamin, blood folate and serum creatinine), and also some other parameters related to diabetes mellitus, such as medical history, metabolic and renal quantities, on two occasions with a 5-year interval in 50 patients with insulin-dependent diabetes mellitus, in order to further elucidate the relation between plasma tHcy and diabetes mellitus. The result of the present study shows that diabetic patients with the lowest age at onset and with the poorest metabolic control are those most prone to a rapid increase in plasma tHcy concentration. The increment in plasma tHcy concentration in this group of patients may at least partly be explained by a marginal deficiency of blood folate concentrations.

Topics: Adult; Age of Onset; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Folic Acid Deficiency; Follow-Up Studies; Homocysteine; Humans; Male; Middle Aged; Vitamin B 12

The reactive vascular-injuring amino acid homocysteine was previously shown to be increased in plasma in diabetic patients with clinical signs of nephropathy. In this study, plasma homocysteine was measured in type 1 diabetic patients with normoalbuminuria (n = 22), microalbuminuria (n = 40) and proteinuria (n = 14) in order to investigate whether plasma homocysteine levels are increased already at the stage of incipient nephropathy, i.e. microalbuminuria. Furthermore, patients were characterized according to the degree of retinopathy. Plasma homocysteine in the whole population (n = 76) was related to B-Folate (r = 0.38, p < 0.01), S-Creatinine (r = 0.55, p < 0.001), S-Urea (r = 0.37, p < 0.01), U-Albumin (r = 0.46, p < 0.001), urinary N-acetyl-beta- glucosaminidase (r = 0.40, p < 0.001), systolic blood pressure (r = 0.36, p < 0.01) and diabetes duration (r = 0.44, p < 0.001). There were no differences in plasma homocysteine levels between patients with normoalbuminuria (8.0 +/- 1.7 mumol l-1; mean +/- SD) and those with microalbuminuria (9.1 +/- 3.4 mumol l-1). However, patients with clinical signs of nephropathy had higher plasma homocysteine levels (12.9 +/- 5.7 mumol l-1, p < 0.01) compared to the other two groups. There was no association between plasma homocysteine levels and different degrees of retinopathy. Thus, the present study does not show any relation between plasma homocysteine levels and early stages of diabetic nephropathy or retinopathy indicating that elevated concentrations of plasma homocysteine does not explain the increased risk for atherosclerosis observed in patients with microalbuminuria.

Topics: Adult; Albuminuria; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Female; Homocysteine; Humans; Male; Middle Aged; Vitamin B 12

Topics: Administration, Oral; Adult; Dark Adaptation; Diabetic Retinopathy; Electroretinography; Female; Humans; Male; Middle Aged; Vitamin B 12

Investigations on the vitamin pattern of diabetic neuropathy: thiamine, riboflavin, pyridoxine, cobalamin and tocopherol. The contents of the vitamins mentioned above have been measured in the blood of 119 patients (53 diabetic neuropathies, 66 diabetics without neuropathy). The incidence of neuropathy shows a strong correlation with the duration of the diabetic state, but not with sex, nor with concomitant diseases such as adipositas, hypertension, heart and circulatory diseases, except retinopathia diabetica. Most of the diabetics in our study are well supplied with vitamins B1, B2, and E; B6 and B12 are occasionally low, but there is no statistically relevant difference between diabetic controls and neuropathies. Adipose patients have neither a markedly different vitamin content nor a different calory uptake from non-adipose patients. A general trend towards reduced total calory uptake is seen in old age, men (lower protein intake) and women (lower carbohydrate intake) obviously differing somewhat in their habits. The influence of therapy on the vitamin pattern is not clear cut, except for patients under diet and biguanide-therapy showing a higher proportion of low or subnormal B12 values. The increased frequency of neuropathies in patients treated with sulfonyl-urea approaches only the limits of significance and needs further investigations.

Topics: Diabetes Complications; Diabetes Mellitus; Diabetic Neuropathies; Diabetic Retinopathy; Female; Humans; Hypertension; Male; Middle Aged; Obesity; Pyridoxine; Riboflavin; Sex Factors; Thiamine; Vitamin B 12; Vitamin E

Topics: Age Factors; Anabolic Agents; Diabetic Retinopathy; Diet Therapy; Dietary Fats; Humans; Hypophysectomy; Light Coagulation; Pituitary Irradiation; Thioctic Acid; Vitamin B 12

Topics: Anticholesteremic Agents; Dextrans; Diabetic Retinopathy; Humans; Inositol; Nicotinic Acids; Sulfates; Thiamine; Vitamin B 12; Vitamin E

Topics: Adolescent; Adult; Blood Vessels; Capillaries; Cobalt Isotopes; Conjunctiva; Diabetes Mellitus; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Female; Glomerular Filtration Rate; Humans; Injections, Intravenous; Vitamin B 12

Topics: Diabetic Retinopathy; Female; Humans; Middle Aged; Vitamin B 12

Topics: Arteriosclerosis; Blood Glucose; Blood Proteins; Cataract; Cholesterol; Classification; Diabetes Mellitus; Diabetic Retinopathy; Eye Manifestations; Fibrinolysin; Humans; Japan; Pathology; Retinitis; Statistics as Topic; Vitamin B 12

Topics: Corrinoids; Diabetes Mellitus; Diabetic Retinopathy; Hematinics; Humans; Kidney Diseases; Vitamin B 12

Topics: Diabetes Complications; Diabetic Retinopathy; Disease; Hematinics; Retina; Retinal Diseases; Vitamin B 12

Topics: Diabetes Complications; Diabetic Retinopathy; Disease; Retina; Retinal Diseases; Vitamin B 12

Topics: Adjuvants, Pharmaceutic; Diabetes Complications; Diabetic Retinopathy; Disease; Humans; Lipotropic Agents; Retina; Retinal Diseases; Vitamin B 12

Topics: Adrenal Cortex; Adrenal Cortex Diseases; Diabetes Complications; Diabetic Retinopathy; Disease; Humans; Retina; Retinal Diseases; Vitamin B 12; Vitamin B 12 Deficiency

Topics: Blood; Corrinoids; Diabetes Mellitus; Diabetic Retinopathy; Disease; Humans; Retina; Retinal Diseases; Vitamin B 12

Topics: Corrinoids; Diabetes Mellitus; Diabetic Retinopathy; Hematinics; Humans; Retina; Vitamin B 12