beta-carotene and Cognition-Disorders

The objective of this review was to evaluate the evidence from human studies on the intake of vitamins, either as monotherapies or in combination with other vitamins, as neuroprotective agents that may delay the onset of cognitive decline in older adults.. Evidence-based methodologies were used to capture and evaluate the highest levels of evidence.. The current evidence available showed no association for cognitive benefits of vitamins B6 or B12 as a monotherapy, and recent systematic reviews provide no clear evidence that supplementation with vitamin B6, B12 and/or folic acid improves dementia outcomes or slows cognitive decline, even though it may normalise homocysteine levels. Meta-analyses from systematic reviews have shown an association between low vitamin D levels and diminished cognitive function, although causality cannot be confirmed from the available evidence. There is no convincing evidence for an association of vitamin A, vitamin C or vitamin E either as a monotherapy or in combination with other antioxidant vitamins such as β-carotene and the prevention of cognitive decline. The appraisal of nineteen systematic reviews and meta-analyses has highlighted the heterogeneity between studies, and the need for better consensus on definitions of cognitive decline, duration of testing and agreement on which specific endpoints are clinically relevant.. Evaluation of the totality of the currently available evidence indicates that intake of the above vitamins, either as a monotherapy, or in combination with other vitamins, has no clinically-relevant effect on delaying cognitive decline or delaying the onset of dementia in older adults.

Topics: Aged; Antioxidants; Ascorbic Acid; beta Carotene; Cognition; Cognition Disorders; Dementia; Dietary Supplements; Folic Acid; Homocysteine; Humans; Meta-Analysis as Topic; Vitamin A; Vitamin B 12; Vitamin B 6; Vitamin D; Vitamin D Deficiency; Vitamin E; Vitamins

Topics: Aged; Aging; Animals; Antioxidants; Ascorbic Acid; beta Carotene; Cognition; Cognition Disorders; Humans; Oxidative Stress; Vitamin E

Few studies have investigated the long-term impact of overall dietary patterns (DP) on cognition. We evaluated the association between empirically derived DP in midlife and cognitive performance 13 y later. Dietary data were based on 24-h dietary records obtained from a subsample of the Supplémentation en Vitamines et Minéraux Antioxydant Study. Cognitive performance was assessed via a battery of neuropsychological tests that included verbal fluency, the RI-48 cued recall test, the trail-making test, and forward and backward digit span. Three composite variables, for global cognitive function, verbal memory, and executive functioning, were built. The multivariate analyses were adjusted for baseline characteristics (age, gender, intervention group, education, alcohol and energy intake, number of dietary records, physical activity, BMI, tobacco use, self-reported memory troubles, diabetes, hypertension, and, for women, menopausal status and hormone therapy use), follow-up time, history of cardiovascular disease, and depressive symptoms. Adjusted means ± SEM of composite variables across quartiles (Q4 vs. Q1) of DP were estimated using ANCOVA. A healthy and a traditional DP were identified. In the multivariate model, the healthy pattern was associated with better global cognitive function (50.1 ± 0.7 vs. 48.9 ± 0.7; P-trend = 0.001) and verbal memory (49.7 ± 0.4 vs. 48.7 ± 0.4; P-trend = 0.01). These relationships were stronger in participants scoring below the gender-specific median values for energy intake (<2490 kcal for men and <1810 for women) than in those scoring at or above those values. Adherence to a healthy DP in middle life may help preserve global cognitive function, especially verbal memory, when total energy intake is regulated.

Topics: Aged; Antioxidants; Ascorbic Acid; beta Carotene; Cognition; Cognition Disorders; Energy Metabolism; Feeding Behavior; Female; Follow-Up Studies; Humans; Male; Memory; Middle Aged; Neuropsychological Tests; Selenium; Verbal Learning; Vitamin E; Vitamins; Zinc

Cardiovascular factors are associated with cognitive decline. Antioxidants may be beneficial.. The Women's Antioxidant Cardiovascular Study was a trial of vitamin E (402 mg every other day), beta carotene (50 mg every other day), and vitamin C (500 mg daily) for the secondary prevention of cardiovascular disease. From 1995 to 1996, women > or =40 years of age with cardiovascular disease or > or =3 coronary risk factors were randomized. From 1998 to 1999, a cognitive function substudy was initiated among 2824 participants > or =65 years of age. With 5 cognitive tests, cognition was assessed by telephone 4 times over 5.4 years. The primary outcome was a global composite score averaging all scores; repeated-measures analyses were used to examine cognitive change over time. Vitamin E supplementation and beta carotene supplementation were not associated with slower rates of cognitive change (mean difference in change for vitamin E versus placebo, -0.01; 95% confidence interval, -0.05 to 0.04; P=0.78; for beta carotene, 0.03; 95% confidence interval, -0.02 to 0.07; P=0.28). Although vitamin C supplementation was associated with better performance at the last assessment (mean difference, 0.13; 95% confidence interval, 0.06 to 0.20; P=0.0005), it was not associated with cognitive change over time (mean difference in change, 0.02; 95% confidence interval, -0.03 to 0.07; P=0.39). Vitamin C was more protective against cognitive change among those with new cardiovascular events during the trial (P for interaction=0.009).. Antioxidant supplementation did not slow cognitive change among women with preexisting cardiovascular disease or cardiovascular disease risk factors. A possible late effect of vitamin C or beta carotene among those with low dietary intake on cognition warrants further study.

Topics: Aged; Aged, 80 and over; Antioxidants; Ascorbic Acid; beta Carotene; Cardiovascular Diseases; Cognition Disorders; Female; Follow-Up Studies; Humans; Memory Disorders; Middle Aged; Neuroprotective Agents; Neuropsychological Tests; Oxidative Stress; Risk Factors; Single-Blind Method; Treatment Failure; Vitamin E

Oxidative stress contributes to brain aging. Antioxidant treatment, especially over the long term, might confer cognitive benefits.. We added cognitive testing to the Physicians' Health Study II (PHSII), a randomized trial of beta carotene and other vitamin supplements for chronic disease prevention. The PHSII is a continuation of the Physicians' Health Study (PHS), which had randomized male participants to low-dose aspirin and beta carotene. Participants include those continuing their original beta carotene assignment from the PHS, begun in 1982, and newer recruits randomized as of 1998. The beta carotene arm (50 mg, alternate days) was terminated; follow-up is ongoing for the remaining arms. Near the close of the beta carotene arm, we interviewed 5956 participants older than 65 years to assess general cognition, verbal memory, and category fluency. The primary end point was a global score averaging all tests (using z scores); the secondary end point was a verbal memory score combining results of 4 tests. We compared mean cognition among those assigned to beta carotene vs placebo. We separately examined new recruits and continuing participants.. Among 1904 newly recruited subjects (mean treatment duration, 1 year), cognition was similar across treatment assignments. Among 4052 continuing participants from the PHS (mean treatment duration, 18 years), the mean global score was significantly higher in the beta carotene group than in the placebo group (mean difference in z scores, 0.047 standard units; P = .03). On verbal memory, men receiving long-term beta carotene supplementation also performed significantly better than the placebo group (mean difference in z scores, 0.063; P = .007).. We did not find an impact of short-term beta carotene supplementation on cognitive performance, but long-term supplementation may provide cognitive benefits.

Topics: Aged; Antioxidants; beta Carotene; Cognition; Cognition Disorders; Dietary Supplements; Humans; Male; Middle Aged; Treatment Outcome

Participants in the Age-Related Eye Disease Study were randomly assigned to receive daily antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; beta carotene, 15 mg), zinc and copper (zinc, 80 mg; cupric oxide, 2 mg), antioxidants plus zinc and copper, or placebo. A cognitive battery was administered to 2,166 elderly persons after a median of 6.9 years of treatment. Treatment groups did not differ on any of the six cognitive tests (p > 0.05 for all). These results do not support a beneficial or harmful effect of antioxidants or zinc and copper on cognition in older adults.

Topics: Aged; Antioxidants; Ascorbic Acid; beta Carotene; Cognition Disorders; Copper; Female; Humans; Male; Middle Aged; Vitamin E; Zinc

To assess the relationship between dietary intake of antioxidants (vitamin C, vitamin E, β-carotene, lutein, flavonoids and lignans) and cognitive decline at middle age, analyses were performed on data from the population based Doetinchem Cohort Study. Habitual diet and cognitive function were assessed twice with a 5-year interval in 2613 persons aged 43-70 year at baseline (1995-2002). Diet was assessed with a validated 178-item semi-quantitative FFQ. Cognitive function was assessed with a neuropsychological test battery, consisting of the 15 Words Learning Test, the Stroop Test, the Word Fluency test, and the Letter Digit Substitution Test. Scores on global cognitive function, memory, processing speed, and cognitive flexibility were calculated. In regression analyses, quintiles of antioxidant intake were associated with change in cognitive domain scores. Results showed that higher lignan intake was linearly associated with less decline in global cognitive function (P= 0.01), memory (P< 0.01) and processing speed (P= 0.04), with about two times less declines in the highest v. the lowest quintile. In the lowest quintile of vitamin E intake, decline in memory was twice as fast as in all higher quintiles (P< 0.01). Global cognitive decline in the highest lutein intake group was greater than in the lowest intake group (P< 0.05). Higher flavonoid intake was associated with greater decline in cognitive flexibility (P for trend = 0.04). Intakes of other antioxidants were not associated with cognitive decline. We conclude that within the range of a habitual dietary intake, higher intake of lignans is associated with less cognitive decline at middle age.

Topics: Adult; Aged; Antioxidants; Ascorbic Acid; beta Carotene; Cognition; Cognition Disorders; Cohort Studies; Diet; Dietary Supplements; Feeding Behavior; Female; Flavonoids; Humans; Lignans; Lutein; Male; Middle Aged; Neuropsychological Tests; Surveys and Questionnaires; Vitamin E

Malnutrition is a widespread problem in elderly people and is associated with cognitive decline. However, interventional studies have produced ambiguous results. For this reason, we wanted to determine the effect of micronutrient supplementation on blood and tissue levels and on general nutritional status in persons with mild or moderate cognitive impairment.. We performed a 2-month, open-label trial, administering a daily micronutrient supplement to 42 memory clinic patients with mild cognitive deficits. Blood levels of antioxidants, zinc, and B vitamins were determined before and after supplementation. In addition, we assessed metabolic markers for B vitamins and intracellular (buccal mucosa cell [BMC]) antioxidant levels. Nutritional status was assessed by using the Mini Nutritional Assessment (MNA).. Blood levels of B vitamins, folic acid, lutein, β-carotene, α-carotene, and α-tocopherol increased significantly. Decreases in homocysteine levels and the thiamine pyrophosphate effect and an increase in holotranscobalamin were observed. We found no increase in intracellular antioxidant levels of BMC. The MNA score in subjects at risk for malnutrition increased significantly, mainly owing to better perception of nutritional and overall health status.. Micronutrient supplementation improved serum micronutrient status, with improved metabolic markers for B vitamins but not for intracellular antioxidant status, and was associated with improved self-perception of general health status. Our data underline the necessity of determining micronutrient status and support the use of additional assessments for general health and quality of life in nutritional supplementation trials.

Topics: Aged; Aged, 80 and over; alpha-Tocopherol; Antioxidants; beta Carotene; Carotenoids; Cognition Disorders; Dietary Supplements; Female; Folic Acid; Humans; Lutein; Male; Micronutrients; Middle Aged; Mouth Mucosa; Nutrition Assessment; Nutritional Status; Pilot Projects; Vitamin B Complex

The hypothesis of carotenoids having a preventive role in cognitive impairment is suggested by their antioxidant properties.. We examined, in a cross-sectional analysis, the relationship between cognitive performance (assessed by the Mini-Mental State Examination, Trail Making Test Part B, Digit Symbol Substitution, Finger Tapping Test, and Word Fluency Test) and different plasma carotenoids (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and trans-beta-carotene and cis-beta-carotene) in a healthy elderly population (the EVA,"Etude du Vieillissement Artériel," study; n = 589, age = 73.5 +/- 3 years).. Logistic regression showed that participants with the lowest cognitive functioning (<25th percentile) had a higher probability of having low levels of specific plasma carotenoids (<1st quartile): lycopene and zeaxanthin. For zeaxanthin, odds ratios (ORs) were as follows: OR(DSS) = 1.97 (95% confidence interval [CI] = 1.21-3.20), OR(FTT) = 1.70 (CI = 1.05-2.74), and OR(WFT) = 1.82 (CI = 1.08-3.07); for lycopene, OR(DSS) = 1.93 (CI = 1.20-3.12) and OR(TMTB) = 1.64 (CI = 1.04-2.59).. Even if it is not possible to affirm if these low levels of carotenoids precede or are the consequence of cognitive impairment, our results suggest that low carotenoid levels could play a role in cognitive impairment. The biological significance of our findings needs further research.

Topics: Aged; Antioxidants; beta Carotene; Carotenoids; Cognition; Cognition Disorders; Cross-Sectional Studies; Cryptoxanthins; Female; Follow-Up Studies; Humans; Longitudinal Studies; Lutein; Lycopene; Male; Mental Status Schedule; Motor Skills; Sensitivity and Specificity; Stereoisomerism; Trail Making Test; Verbal Behavior; Xanthophylls; Zeaxanthins

Topics: Alzheimer Disease; Antioxidants; beta Carotene; Clinical Trials as Topic; Cognition Disorders; Humans; Time Factors; Treatment Outcome; Vitamin E

Growing evidence from animal studies suggests an interaction between antioxidants and apolipoprotein E (APOE) alleles on cognitive functioning. We used data from a 7-year cohort study of high-functioning older persons to explore whether the associations between serum beta-carotene level and subsequent decline of cognitive function differed by APOE 4 genotype.. Baseline information on sociodemographic characteristics, serum beta-carotene level, inflammation markers, APOE genotype, and cognitive functioning measured by a 9-item Short Portable Mental Status Questionnaire (SPMSQ) was obtained in 455 survivors. Multivariable logistic regression analyses were used to examine the relation between high serum beta-carotene level and risk of SPMSQ score decline in participants with or without APOE 4 alleles, while adjusting for age, sex, race, baseline SPMSQ score, and other covariates.. Nine (2%) study participants had homozygous and 97 (21%) had heterozygous APOE 4 alleles. Two hundred forty-nine (55%) had decline of SPMSQ scores during the follow-up. The presence of an APOE 4 allele was associated with higher risk and larger magnitude of SPMSQ score decline. The adjusted odds ratio of high beta-carotene level for cognitive decline was 0.11 (95% confidence interval, 0.02-0.57) in participants with at least one APOE 4 allele and 0.89 (95% confidence interval, 0.54-1.47) among those who were APOE 4 negative.. Among high-functioning older persons, antioxidants and beta-carotene in particular may offer protection from cognitive decline in persons with greater genetic susceptibility as evidenced by the presence of the APOE 4 allele.

Topics: Activities of Daily Living; Aged; Aging; Alleles; Apolipoprotein E4; Apolipoproteins E; beta Carotene; Biomarkers; Cognition Disorders; Enzyme-Linked Immunosorbent Assay; Female; Follow-Up Studies; Genotype; Humans; Male; Retrospective Studies; Risk Factors

Aging processes, and among them brain aging, are thought to be associated with free radical action. It is hypothesized that plasma antioxidant vitamin levels correlate with cognitive performance in healthy older subjects.. Longitudinal and cross-sectional comparisons.. The city of Basle, considered representative of the older urban population in Switzerland.. A total of 442 subjects aged 65 to 94 years (mean: 75 years; 312 male, 132 female) was selected from a random sample.. In 1993, participants were tested for memory, and plasma vitamin levels were measured for the three antioxidants alpha-tocopherol, ascorbic acid, and beta-carotene. These vitamin parameters, measured previously in 1971 in the same sample, were integrated in our analyses. In addition, plasma cholesterol, ferritin, and systolic blood pressure were taken into account. Memory variables were priming, working-memory, free recall, recognition and the WAIS-R vocabulary test (semantic memory).. Correlations showed significant stability of the plasma antioxidants over the time lag of 22 years (alpha-tocopherol: r = .47, P < or = .001; beta-carotene: r = .43, P < .001; ascorbic acid: r = .22, P < .001). Free recall, recognition, and vocabulary (but not priming and working-memory) correlated significantly with ascorbic acid and beta-carotene in the cross-sectional 1993 data as well as in the longitudinal 1971-1993 analysis. These two antioxidants remained significant predictors, especially of semantic memory, after controlling for possible confounding variables like age, education, and gender using multiple regression analyses and ANOVAs.. Among people aged 65 and older, higher ascorbic acid and beta-carotene plasma level are associated with better memory performance. These results indicate the important role played by antioxidants in brain aging and may have implications for prevention of progressive cognitive impairments.

Topics: Aged; Aging; Antioxidants; Ascorbic Acid; beta Carotene; Cognition Disorders; Cross-Sectional Studies; Female; Free Radicals; Humans; Longitudinal Studies; Male; Memory; Regression Analysis; Vitamin E; Wechsler Scales