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Zhang L, Chen X, Chen Y, Yan J, Huang G, Li W. A Comparative Study Evaluating the Effectiveness of Folate-Based B Vitamin Intervention on Cognitive Function of Older Adults under Mandatory Folic Acid Fortification Policy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients 2024; 16:2199. [PMID: 39064642 PMCID: PMC11279592 DOI: 10.3390/nu16142199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 07/06/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024] Open
Abstract
The policies regarding the mandatory fortification of food with folic acid (FA) may impact the effectiveness of folate-based B vitamin treatment on cognitive function in older adults. We critically and systematically review the literature to assess whether food fortification policies affect folate-based B vitamin treatment efficacy on cognition function in older adults. Electronic databases, including PubMed, Web of Science, and CNKI, were searched for "Cognitive Function", "Folate", and "Older Adults". The study had specific criteria for inclusion, which were as follows: (1) the studies should initially have randomized controlled trials that were conducted on older adults aged 60 or above; (2) the studies must assess the relationship between folate status and cognitive performance; and (3) the studies should clarify the policies regarding food fortification with FA. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. Two reviewers independently extracted all the data, and any discrepancies were resolved by consensus. All the data collected were compiled, compared, and analyzed critically. Random effects models were used to assess the effects of interventions. The systematic review included fifty-one articles involving 42,768 participants. Of these, the 23 articles were included in the meta-analysis. The meta-analysis on the effects of folate-based B vitamin supplementation on cognitive function showed a significant overall impact (Z = 3.84; p = 0.0001; SMD, 0.18; 95% CI, 0.09, 0.28). Further analysis revealed that FA food fortification policies were not implemented in countries where folate-based B vitamin supplementation improved cognitive impairment in older adults (Z = 3.75; p = 0.0002; SMD, 0.27; 95% CI, 0.13, 0.40). However, the FA intervention did not have significant outcomes in areas where FA food fortification policies were mandatory (Z = 0.75; p = 0.45; SMD, 0.03; 95% CI, -0.06, 0.13). Supplementing with oral folic acid, alone or in combination, has been linked to improved cognitive performance in older adults. While mandatory FA fortification has the improved folic acid status, additional folate-based B vitamin supplements do not appear to influence cognitive function.
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Affiliation(s)
- Liyang Zhang
- Department of Nutrition and Food Science, School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China; (L.Z.); (X.C.); (G.H.)
| | - Xukun Chen
- Department of Nutrition and Food Science, School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China; (L.Z.); (X.C.); (G.H.)
| | - Yongjie Chen
- Department of Epidemiology & Biostatistics, School of Public Health, Tianjin Medical University, Tianjin 300070, China;
- Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin 300070, China;
| | - Jing Yan
- Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin 300070, China;
- Department of Social Medicine and Health Administration, School of Public Health, Tianjin Medical University, Tianjin 300070, China
| | - Guowei Huang
- Department of Nutrition and Food Science, School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China; (L.Z.); (X.C.); (G.H.)
- Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin 300070, China;
| | - Wen Li
- Department of Nutrition and Food Science, School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China; (L.Z.); (X.C.); (G.H.)
- Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin 300070, China;
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Abrego-Guandique DM, Bonet ML, Caroleo MC, Cannataro R, Tucci P, Ribot J, Cione E. The Effect of Beta-Carotene on Cognitive Function: A Systematic Review. Brain Sci 2023; 13:1468. [PMID: 37891835 PMCID: PMC10605009 DOI: 10.3390/brainsci13101468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/11/2023] [Accepted: 10/15/2023] [Indexed: 10/29/2023] Open
Abstract
β-carotene is a powerful antioxidant and dietary precursor of vitamin A whose role in maintaining mental health and cognitive performance, either alone or in combination with other dietary compounds, has been a topic of recent research. However, its effectiveness is still unclear. This systematic review, conducted according to the PRISMA guideline and assisted by the MySLR platform, addressed this issue. A total of 16 eligible original research articles were identified. Dietary intake or β-carotene serum levels were associated with improved measures of cognitive function in 7 out of 10 epidemiological studies included. In intervention studies, β-carotene consumption alone did not promote better cognitive function in the short term, but only in a long-term intervention with a mean duration of 18 years. However, all but one intervention study suggested the beneficial effects of β-carotene supplementation at doses ranging from 6 mg to 50 mg per day in combination with a multicomplex such as vitamin E, vitamin C, zinc, or selenium for a period of 16 weeks to 20 years. Despite the current limitations, the available evidence suggests a potential association between β-carotene dietary/supplementary intake and the maintenance of cognitive function. The β-carotene most probably does not act alone but in synergy with other micronutrients.
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Affiliation(s)
- Diana Marisol Abrego-Guandique
- Department of Health Sciences, University of Magna Graecia Catanzaro, 88100 Catanzaro, Italy; (D.M.A.-G.); (M.C.C.)
- Galascreen Laboratories, University of Calabria, 87036 Rende, Italy;
| | - Maria Luisa Bonet
- Laboratory of Molecular Biology, Nutrition, and Biotechnology (LBNB), Universitat de les Illes Balears, 07122 Palma, Spain; (M.L.B.); (J.R.)
- Institut d’Investigació Sanitària Illes Balears (IdISBa), 07120 Palma, Spain
- CIBER de Fisiopatología de la Obesidad y Nutrición (CIBERobn), 07122 Palma, Spain
| | - Maria Cristina Caroleo
- Department of Health Sciences, University of Magna Graecia Catanzaro, 88100 Catanzaro, Italy; (D.M.A.-G.); (M.C.C.)
- Galascreen Laboratories, University of Calabria, 87036 Rende, Italy;
| | - Roberto Cannataro
- Galascreen Laboratories, University of Calabria, 87036 Rende, Italy;
- Research Division, Dynamical Business & Science Society, DBSS International SAS, Bogota 110311, Colombia
| | - Paola Tucci
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy;
| | - Joan Ribot
- Laboratory of Molecular Biology, Nutrition, and Biotechnology (LBNB), Universitat de les Illes Balears, 07122 Palma, Spain; (M.L.B.); (J.R.)
- Institut d’Investigació Sanitària Illes Balears (IdISBa), 07120 Palma, Spain
- CIBER de Fisiopatología de la Obesidad y Nutrición (CIBERobn), 07122 Palma, Spain
| | - Erika Cione
- Galascreen Laboratories, University of Calabria, 87036 Rende, Italy;
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy;
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Young LM, Gauci S, Arnoldy L, Martin L, Perry N, White DJ, Meyer D, Lassemillante AC, Ogden E, Silber B, Scholey A, Pipingas A. Investigating the Effects of a Multinutrient Supplement on Cognition, Mood and Biochemical Markers in Middle-Aged Adults with 'Optimal' and 'Sub-Optimal' Diets: A Randomized Double Blind Placebo Controlled Trial. Nutrients 2022; 14:nu14235079. [PMID: 36501109 PMCID: PMC9741460 DOI: 10.3390/nu14235079] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 12/05/2022] Open
Abstract
Background: Previous randomized controlled trials examining cognitive and mood effects of combination multivitamin supplements in healthy, non-clinical adults have reported mixed results. One purported explanation for this is that the dietary status of participants at the start of supplement interventions may influence the magnitude of the effect of supplementation. Methods: In this study, we evaluated the effect of a multinutrient formula containing B group vitamins, Bacopa monniera and Ginkgo biloba on memory, attention, mood and biochemical markers of nutrient status in middle-aged adults (M = 52.84 years, n = 141) with 'optimal' and 'sub-optimal' diets over 12 weeks. We hypothesised that active supplementation would differentially improve memory and attention in those with a 'sub-optimal' diet. Results: Mixed model, repeated measures analysis revealed that, in comparison to placebo, active treatment was associated with significant increases in B vitamin status (B1, B6, B12). Regarding behavioural outcomes there was no significant benefit to memory (F(1, 113.51) = 0.53, p = 0.470) nor attention (F(1,113.77) = 1.89, p = 0.171) in the whole cohort. Contrary to our hypothesis, there was a significant beneficial effect of supplementation on attentional performance in individuals with an 'optimal' diet prior to supplementation (F(1,57.25) = 4.94, p = 0.030). In the absence of a main effect of supplementation across the entire cohort, there were also a number of significant three-way interactions (treatment by time by diet group) detected in secondary outcomes including lower state anxiety and mental fatigue in those with an 'optimal' diet. Conclusion: These findings suggest that the cognitive benefit of B vitamin and herbal supplementation may be dependent on diet quality, supporting the concepts of 'co-nutrient optimisation' and interdependency of nutrients. This warrants further investigation. This study advocates characterising the diet of participants prior to supplementation as it may influence the effect of a nutraceutical intervention.
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Affiliation(s)
- Lauren M. Young
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
| | - Sarah Gauci
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
- Food & Mood Centre, The Institute for Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, VIC 3220, Australia
| | - Lizanne Arnoldy
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
| | - Laura Martin
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
| | - Naomi Perry
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
| | - David J. White
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
| | - Denny Meyer
- Department of Health Sciences and Biostatistics, Swinburne University, Melbourne, VIC 3122, Australia
- Centre for Mental Health, Swinburne University, Melbourne, VIC 3122, Australia
| | - Annie-Claude Lassemillante
- Department of Nursing and Allied Health, Faculty of Health, Arts and Design, Swinburne University, Melbourne, VIC 3122, Australia
| | - Edward Ogden
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
| | - Beata Silber
- Swisse Wellness Pty Ltd., Melbourne, VIC 3066, Australia
| | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, VIC 3168, Australia
| | - Andrew Pipingas
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, VIC 3122, Australia
- Correspondence:
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Beydoun MA, Canas JA, Fanelli-Kuczmarski MT, Maldonado AI, Shaked D, Kivimaki M, Evans MK, Zonderman AB. Association of Antioxidant Vitamins A, C, E and Carotenoids with Cognitive Performance over Time: A Cohort Study of Middle-Aged Adults. Nutrients 2020; 12:nu12113558. [PMID: 33233594 PMCID: PMC7699702 DOI: 10.3390/nu12113558] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/10/2020] [Accepted: 11/16/2020] [Indexed: 12/31/2022] Open
Abstract
Carotenoids may strengthen the association of antioxidant vitamins A, C, and E with favorable cognitive outcomes over time, though a few prospective studies have examined this hypothesis. We evaluated the longitudinal data from 1251 participants in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study (Age at visit 1 in 2004–2009 (v1): 30–65 years). Vitamins A, C, and E dietary intakes and total and individual dietary carotenoids were computed using two 24-h recalls at v1. Cognitive tests, covering global mental status and domains of memory/learning, attention, psychomotor speed, visuo-spatial, language/verbal, and executive function were conducted at v1 and/or v2 (2009–2013); mean ± SD follow-up: 4.66 ± 0.93 years. Mixed-effects linear regression models detected an interaction between vitamin E and total (and individual) carotenoids for three of 11 cognitive tests at v1, with only one meeting the statistical significance upon multiple testing correction whereby vitamin E was linked with greater verbal memory performance in the uppermost total carotenoid tertile (γ0a = +0.26 ± 0.08, p = 0.002), a synergism largely driven by carotenoid lycopene. Vitamins A and C showed no consistent interactions with carotenoids. In conclusion, we provide partial evidence for synergism between vitamin E and carotenoids in relation to better baseline cognitive performance, pending further studies with time-dependent exposures and randomized trials directly examining this synergism.
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Affiliation(s)
- May A. Beydoun
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, Intramural Research Program, NIA/NIH/IRP, Baltimore, MD 21224, USA; (A.I.M.); (M.K.E.); (A.B.Z.)
- Correspondence: ; Fax: +1-410-558-8236
| | - Jose A. Canas
- Department of Pediatrics, Johns Hopkins Medical Institutions, Saint Petersburg, FL 33701, USA;
| | | | - Ana I. Maldonado
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, Intramural Research Program, NIA/NIH/IRP, Baltimore, MD 21224, USA; (A.I.M.); (M.K.E.); (A.B.Z.)
| | - Danielle Shaked
- Department of Psychology, VA Boston Healthcare System, Boston, MA 02130, USA;
| | - Mika Kivimaki
- Department of Epidemiology and Public Health, University College London, London WC1E 6BT, UK;
| | - Michele K. Evans
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, Intramural Research Program, NIA/NIH/IRP, Baltimore, MD 21224, USA; (A.I.M.); (M.K.E.); (A.B.Z.)
| | - Alan B. Zonderman
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, Intramural Research Program, NIA/NIH/IRP, Baltimore, MD 21224, USA; (A.I.M.); (M.K.E.); (A.B.Z.)
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Behrens A, Graessel E, Pendergrass A, Donath C. Vitamin B-Can it prevent cognitive decline? A systematic review and meta-analysis. Syst Rev 2020; 9:111. [PMID: 32414424 PMCID: PMC7229605 DOI: 10.1186/s13643-020-01378-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 05/04/2020] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Development of cognitive decline represents substantial issues in today's society, steadily gaining importance with increasing life expectancy. One potential approach to preventing cognitive decline is to lower homocysteine by administering vitamin B. In this systematic review and meta-analysis, we address this topic and investigate whether oral supplementation of vitamin B can successfully prevent cognitive decline in cognitively unimpaired individuals. METHODS A computerized systematic literature search was conducted using the electronic databases PubMed, Embase, and the Cochrane Library. Eligibility criteria included oral supplementation with vitamin B (B1, B6, folic acid, and B12) and the absence of cognitive impairment. A meta-analysis was conducted with "global cognition" as the primary outcome of this review. Secondary outcomes were changes in cognitive function in other cognitive domains reported in the included studies. Risk of bias was assessed according to the Cochrane Risk of Bias tool and the GRADE approach to establish the overall certainty of the evidence. RESULTS The meta-analysis did not yield a significant overall effect of supplementation with vitamin B on cognitive function (Z = 0.87; p = 0.39; SMD, 0.02; 95% CI, - 0.034, 0.08). A sensitivity analysis focusing on specific risk factors did not alter this result. Some studies reported isolated significant effects of the intervention on secondary outcomes. However, these findings were outnumbered by the number of cognitive tests that did not yield significant effects. DISCUSSION We found no overall evidence that oral vitamin B supplementation prevented cognitive decline. The isolated significant effects that were reported could be attributed to methodological issues. The results of this review do not provide evidence that population groups with certain risk factors would profit more from the intervention than others. Our findings do not apply to forms of administration other than oral supplementation nor do they offer information regarding the treatment of cognitively impaired individuals via the administration of vitamin B. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42017071692.
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Affiliation(s)
- Annika Behrens
- Center of Health Services Research in Medicine, Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany.
| | - Elmar Graessel
- Center of Health Services Research in Medicine, Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Anna Pendergrass
- Center of Health Services Research in Medicine, Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Carolin Donath
- Center of Health Services Research in Medicine, Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
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Effects of Lutein and Astaxanthin Intake on the Improvement of Cognitive Functions among Healthy Adults: A Systematic Review of Randomized Controlled Trials. Nutrients 2020; 12:nu12030617. [PMID: 32120794 PMCID: PMC7146131 DOI: 10.3390/nu12030617] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/22/2020] [Accepted: 02/24/2020] [Indexed: 12/31/2022] Open
Abstract
Background: Fruits and vegetables are generally rich in antioxidants such as carotenoids. Consumption of carotenoids is expected to have benefits on cognitive functions in humans. However, previous randomized controlled trials (RCT) using carotenoids have reported inconsistent results. Therefore, this systematic review (SR) aimed to summarize the effect of carotenoid intake on cognitive functions in humans. Method: PubMed, Cochrane Library, Web of Science, and PsychoINFO were searched for research papers on carotenoid intake with the criteria that 1) oral carotenoid intake was evaluated using RCTs, 2) participants were healthy young, middle-aged, or older, and 3) cognitive functions were measured using RCTs. Results: Five studies using lutein and two studies using astaxanthin met the inclusion criteria. Consumption of lutein and its isomer showed consistent results in selective improvement of visual episodic memory in young and middle-aged adults while inhibition was observed in middle-aged and older adults. One of the two included astaxanthin studies reported a significant improvement of verbal episodic memory performance in middle-aged adults. Conclusion: This SR showed that the 10 mg lutein per day for twelve months can lead to improvement of cognitive functions. Due to the small number of studies, it is difficult to conclude whether astaxanthin would have a positive effect on cognitive functions.
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Rutjes AWS, Denton DA, Di Nisio M, Chong L, Abraham RP, Al‐Assaf AS, Anderson JL, Malik MA, Vernooij RWM, Martínez G, Tabet N, McCleery J. Vitamin and mineral supplementation for maintaining cognitive function in cognitively healthy people in mid and late life. Cochrane Database Syst Rev 2018; 12:CD011906. [PMID: 30556597 PMCID: PMC6353240 DOI: 10.1002/14651858.cd011906.pub2] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Vitamins and minerals play multiple functions within the central nervous system which may help to maintain brain health and optimal cognitive functioning. Supplementation of the diet with various vitamins and minerals has been suggested as a means of maintaining cognitive function, or even of preventing dementia, in later life. OBJECTIVES To evaluate the effects of vitamin and mineral supplementation on cognitive function in cognitively healthy people aged 40 years or more. SEARCH METHODS We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov and the WHO Portal/ICTRP from inception to 26th January 2018. SELECTION CRITERIA We included randomised controlled trials that evaluated the cognitive effects on people aged 40 years or more of any vitamin or mineral supplements taken by mouth for at least three months. DATA COLLECTION AND ANALYSIS Study selection, data extraction, and quality assessments were done in duplicate. Vitamins were considered broadly in the categories of B vitamins, antioxidant vitamins, and combinations of both. Minerals were considered separately, where possible. If interventions and outcomes were considered sufficiently similar, then data were pooled. In order to separate short-term cognitive effects from possible longer-term effects on the trajectory of cognitive decline, data were pooled for various treatment durations from 3 months to 12 months and up to 10 years or more. MAIN RESULTS In total, we included 28 studies with more than 83,000 participants. There were some general limitations of the evidence. Most participants were enrolled in studies which were not designed primarily to assess cognition. These studies often had no baseline cognitive assessment and used only brief cognitive assessments at follow-up. Very few studies assessed the incidence of dementia. Most study reports did not mention adverse events or made only very general statements about them. Only 10 studies had a mean follow-up > 5 years. Only two studies had participants whose mean age was < 60 years at baseline. The risk of bias in the included studies was generally low, other than a risk of attrition bias for longer-term outcomes. We considered the certainty of the evidence behind almost all results to be moderate or low.We included 14 studies with 27,882 participants which compared folic acid, vitamin B12, vitamin B6, or a combination of these to placebo. The majority of participants were aged over 60 years and had a history of cardio- or cerebrovascular disease. We found that giving B vitamin supplements to cognitively healthy adults, mainly in their 60s and 70s, probably has little or no effect on global cognitive function at any time point up to 5 years (SMD values from -0.03 to 0.06) and may also have no effect at 5-10 years (SMD -0.01). There were very sparse data on adverse effects or on incidence of cognitive impairment or dementia.We included 8 studies with 47,840 participants in which the active intervention was one or more of the antioxidant vitamins: ß-carotene, vitamin C or vitamin E. Results were mixed. For overall cognitive function, there was low-certainty evidence of benefit associated with ß-carotene after a mean of 18 years of treatment (MD 0.18 TICS points, 95% CI 0.01 to 0.35) and of vitamin C after 5 years to 10 years (MD 0.46 TICS points, 95% CI 0.14 to 0.78), but not at earlier time points. From two studies which reported on dementia incidence, there was low-certainty evidence of no effect of an antioxidant vitamin combination or of vitamin E, either alone or combined with selenium. One of the included studies had been designed to look for effects on the incidence of prostate cancer; it found a statistically significant increase in prostate cancer diagnoses among men taking vitamin E.One trial with 4143 participants compared vitamin D3 (400 IU/day) and calcium supplements to placebo. We found low- to moderate-certainty evidence of no effect of vitamin D3 and calcium supplements at any time-point up to 10 years on overall cognitive function (MD after a mean of 7.8 years -0.1 MMSE points, 95% CI -0.81 to 0.61) or the incidence of dementia (HR 0.94, 95% CI 0.72 to 1.24). A pilot study with 60 participants used a higher dose of vitamin D3 (4000 IU on alternate days) and found preliminary evidence that this dose probably has no effect on cognitive function over six months.We included data from one trial of zinc and copper supplementation with 1072 participants. There was moderate-certainty evidence of little or no effect on overall cognitive function (MD 0.6 MMSE points, 95% CI -0.19 to 1.39) or on the incidence of cognitive impairment after 5 years to 10 years. A second smaller trial provided no usable data, but reported no cognitive effects of six months of supplementation with zinc gluconate.From one study with 3711 participants, there was low-certainty evidence of no effect of approximately five years of selenium supplementation on the incidence of dementia (HR 0.83, 95% CI 0.61 to 1.13).Finally, we included three trials of complex supplements (combinations of B vitamins, antioxidant vitamins, and minerals) with 6306 participants. From the one trial which assessed overall cognitive function, there was low-certainty evidence of little or no effect on the TICS (MD after a mean of 8.5 years 0.12, 95% CI -0.14 to 0.38). AUTHORS' CONCLUSIONS We did not find evidence that any vitamin or mineral supplementation strategy for cognitively healthy adults in mid or late life has a meaningful effect on cognitive decline or dementia, although the evidence does not permit definitive conclusions. There were very few data on supplementation starting in midlife (< 60 years); studies designed to assess cognitive outcomes tended to be too short to assess maintenance of cognitive function; longer studies often had other primary outcomes and used cognitive measures which may have lacked sensitivity. The only positive signals of effect came from studies of long-term supplementation with antioxidant vitamins. These may be the most promising for further research.
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Affiliation(s)
- Anne WS Rutjes
- University of BernInstitute of Social and Preventive Medicine (ISPM)Mittelstrasse 43BernBernSwitzerland3012
- University of BernInstitute of Primary Health Care (BIHAM)Mittelstrasse 43BernBernSwitzerland3012
| | - David A Denton
- Sussex Partnership NHS Foundation TrustSpecialist Older People's ServicesUckfield Community HosptialFramfield RoadUckfieldUKTN22 5AW
| | - Marcello Di Nisio
- University "G. D'Annunzio" of Chieti‐PescaraDepartment of Medicine and Ageing SciencesVia dei Vestini 31Chieti ScaloItaly66013
| | | | - Rajesh P Abraham
- Surrey and Borders Partnership NHS Foundation TrustCommunity Mental Health Team for Older People:Waverley11‐13 Ockford RoadGuildfordUKGU7 1QU
| | - Aalya S Al‐Assaf
- Newcastle UniversityNIHR Innovation ObservatorySuite A, 4th Floor, Time CentralGallowgateNewcastle Upon TyneUKNE1 4BF
| | - John L Anderson
- Brighton and Sussex Medical School, University of BrightonDepartment of Medical EducationWatson BuildingFalmerUKBN1 9PH
| | - Muzaffar A Malik
- Brighton and Sussex Medical School, University of BrightonDepartment of Medical Education (Postgraduate)Room 341, Mayfield HouseFalmerUKBN1 9PH
| | - Robin WM Vernooij
- Iberoamerican Cochrane CentreC/ Sant Antoni Maria Claret 167BarcelonaBarcelonaSpain08025
| | - Gabriel Martínez
- Universidad de AntofagastaFaculty of Medicine and DentistryAvenida Argentina 2000AntofagastaChile127001
| | - Naji Tabet
- Brighton and Sussex Medical SchoolCentre for Dementia StudiesMayfield House, University of BrightonFalmerBrightonUKBN1 9PH
| | - Jenny McCleery
- Oxford Health NHS Foundation TrustElms CentreOxford RoadBanburyOxfordshireUKOX16 9AL
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McCleery J, Abraham RP, Denton DA, Rutjes AWS, Chong L, Al‐Assaf AS, Griffith DJ, Rafeeq S, Yaman H, Malik MA, Di Nisio M, Martínez G, Vernooij RWM, Tabet N. Vitamin and mineral supplementation for preventing dementia or delaying cognitive decline in people with mild cognitive impairment. Cochrane Database Syst Rev 2018; 11:CD011905. [PMID: 30383288 PMCID: PMC6378925 DOI: 10.1002/14651858.cd011905.pub2] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Vitamins and minerals have many functions in the nervous system which are important for brain health. It has been suggested that various different vitamin and mineral supplements might be useful in maintaining cognitive function and delaying the onset of dementia. In this review, we sought to examine the evidence for this in people who already had mild cognitive impairment (MCI). OBJECTIVES To evaluate the effects of vitamin and mineral supplementation on cognitive function and the incidence of dementia in people with mild cognitive impairment. SEARCH METHODS We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CENTRAL, CINAHL, LILACs, Web of Science Core Collection, ClinicalTrials.gov, and the WHO Portal/ICTRP, from inception to 25 January 2018. SELECTION CRITERIA We included randomised or quasi-randomised, placebo-controlled trials which evaluated orally administered vitamin or mineral supplements in participants with a diagnosis of mild cognitive impairment and which assessed the incidence of dementia or cognitive outcomes, or both. We were interested in studies applicable to the general population of older people and therefore excluded studies in which participants had severe vitamin or mineral deficiencies. DATA COLLECTION AND ANALYSIS We sought data on our primary outcomes of dementia incidence and overall cognitive function and on secondary outcomes of episodic memory, executive function, speed of processing, quality of life, functional performance, clinical global impression, adverse events, and mortality. We conducted data collection and analysis according to standard Cochrane systematic review methods. We assessed the risk of bias of included studies using the Cochrane 'Risk of bias' assessment tool. We grouped vitamins and minerals according to their putative mechanism of action and, where we considered it to be clinically appropriate, we pooled data using random-effects methods. We used GRADE methods to assess the overall quality of evidence for each comparison and outcome. MAIN RESULTS We included five trials with 879 participants which investigated B vitamin supplements. In four trials, the intervention was a combination of vitamins B6, B12, and folic acid; in one, it was folic acid only. Doses varied. We considered there to be some risks of performance and attrition bias and of selective outcome reporting among these trials. Our primary efficacy outcomes were the incidence of dementia and scores on measures of overall cognitive function. None of the trials reported the incidence of dementia and the evidence on overall cognitive function was of very low-quality. There was probably little or no effect of B vitamins taken for six to 24 months on episodic memory, executive function, speed of processing, or quality of life. The evidence on our other secondary clinical outcomes, including harms, was very sparse or very low-quality. There was evidence from one study that there may be a slower rate of brain atrophy over two years in participants taking B vitamins. The same study reported subgroup analyses based on the level of serum homocysteine (tHcy) at baseline and found evidence that B vitamins may improve episodic memory in those with tHcy above the median at baseline.We included one trial (n = 516) of vitamin E supplementation. Vitamin E was given as 1000 IU of alpha-tocopherol twice daily. We considered this trial to be at risk of attrition and selective reporting bias. There was probably no effect of vitamin E on the probability of progression from MCI to Alzheimer's dementia over three years (HR 1.02; 95% CI 0.74 to 1.41; n = 516; 1 study, moderate-quality evidence). There was also no evidence of an effect at intermediate time points. The available data did not allow us to conduct analyses, but the authors reported no significant effect of three years of supplementation with vitamin E on overall cognitive function, episodic memory, speed of processing, clinical global impression, functional performance, adverse events, or mortality (five deaths in each group). We considered this to be low-quality evidence.We included one trial (n = 256) of combined vitamin E and vitamin C supplementation and one trial (n = 26) of supplementation with chromium picolinate. In both cases, there was a single eligible cognitive outcome, but we considered the evidence to be very low-quality and so could not be sure of any effects. AUTHORS' CONCLUSIONS The evidence on vitamin and mineral supplements as treatments for MCI is very limited. Three years of treatment with high-dose vitamin E probably does not reduce the risk of progression to dementia, but we have no data on this outcome for other supplements. Only B vitamins have been assessed in more than one RCT. There is no evidence for beneficial effects on cognition of supplementation with B vitamins for six to 24 months. Evidence from a single study of a reduced rate of brain atrophy in participants taking vitamin B and a beneficial effect of vitamin B on episodic memory in those with higher tHcy at baseline warrants attempted replication.
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Affiliation(s)
- Jenny McCleery
- Oxford Health NHS Foundation TrustElms CentreOxford RoadBanburyOxfordshireUKOX16 9AL
| | - Rajesh P Abraham
- Surrey and Borders Partnership NHS Foundation TrustCommunity Mental Health Team for Older People:Waverley11‐13 Ockford RoadGuildfordUKGU7 1QU
| | - David A Denton
- Sussex Partnership NHS Foundation TrustSpecialist Older People's ServicesUckfield Community HosptialFramfield RoadUckfieldUKTN22 5AW
| | - Anne WS Rutjes
- Fondazione "Università G. D'Annunzio"Centre for Systematic ReviewsVia dei Vestini 31ChietiChietiItaly66100
- University of BernInstitute of Social and Preventive Medicine (ISPM)Mittelstrasse 43BernBernSwitzerland3012
| | | | - Aalya S Al‐Assaf
- Newcastle UniversityNIHR Innovation ObservatorySuite A, 4th Floor, Time CentralGallowgateNewcastle Upon TyneUKNE1 4BF
| | - Daniel J Griffith
- Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham NHS Foundation TrustDepartment of Nutrition and DieteticsMindelsohn WayEdgbastonBirminghamWest MidlandsUKB15 2GW
| | - Shireen Rafeeq
- Central Park Medical CollegeCommunity MedicineCentral Park Housing Scheme, Ferozepur Road, Kahna NauLahorePunjabPakistan53100
| | - Hakan Yaman
- Faculty of Medicine, Akdeniz UniversityDepartment of Family MedicineAntalyaTurkey07059
| | - Muzaffar A Malik
- Brighton and Sussex Medical School, University of BrightonDepartment of Medical Education (Postgraduate)Room 341, Mayfield HouseFalmerUKBN1 9PH
| | - Marcello Di Nisio
- University "G. D'Annunzio" of Chieti‐PescaraDepartment of Medicine and Ageing SciencesVia dei Vestini 31Chieti ScaloItaly66013
| | - Gabriel Martínez
- Universidad de AntofagastaFaculty of Medicine and DentistryAvenida Argentina 2000AntofagastaChile127001
- Iberoamerican Cochrane CentreSant Antoni Maria Claret 167BarcelonaSpain08025
| | - Robin WM Vernooij
- Iberoamerican Cochrane CentreSant Antoni Maria Claret 167BarcelonaSpain08025
| | - Naji Tabet
- Brighton and Sussex Medical SchoolCentre for Dementia StudiesMayfield House, University of BrightonFalmerBrightonUKBN1 9PH
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Ma F, Li Q, Zhou X, Zhao J, Song A, Li W, Liu H, Xu W, Huang G. Effects of folic acid supplementation on cognitive function and Aβ-related biomarkers in mild cognitive impairment: a randomized controlled trial. Eur J Nutr 2017; 58:345-356. [DOI: 10.1007/s00394-017-1598-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 12/13/2017] [Indexed: 12/21/2022]
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Khan A, Shafiq I, Hassan Shah M. Prevalence of Vitamin B12 Deficiency in Patients with Type II Diabetes Mellitus on Metformin: A Study from Khyber Pakhtunkhwa. Cureus 2017; 9:e1577. [PMID: 29057189 PMCID: PMC5647126 DOI: 10.7759/cureus.1577] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Background Metformin is the most common oral hypoglycemic used and associated with certain abnormalities. The objective was to evaluate and define the occurrence and bases of vitamin B12 deficiency amongst patients on Metformin for diabetes mellitus type II. Methods A cross-sectional study was conducted on 209 patients having diabetes type II between January-December 2016. The patients aged > 45 years and who had taken metformin for at least three months were recruited with regular follow-up at the Endocrinology Unit of Hayatabad Medical Complex and Diabetic Center Hayatabad, Peshawar. The patients were included in a survey after which they had their serum B12 levels measured. Serum B12 levels < 150 pg/ml is defined as the B12 deficiency. Results About 29.66% of diabetic patients had confirmed the B12 insufficiency through laboratory tests. The patients on metformin had statistically lower values of B12 (P = 0.01). For the patients who smoked, vitamin B12 deficiency was significantly higher than those who did not smoke (p= <0.001). Also in patients using multivitamins, vitamin B12 deficiency was lower compared to nonusers (p=0.05). Conclusion Our study shows that for the patients with type 2 diabetes (T2DM), long-term treatment with metformin and smoking are associated with higher chances of developing vitamin B12 deficiency. Clinicians should, therefore, recognize this significant element and should screen diabetics who are on metformin treatment for any B12 insufficiency, which may be hidden, especially patients coming with neurologic symptoms. Additionally, multi vitamins taken daily may have a protective role.
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Affiliation(s)
- Adnan Khan
- House Officer, Rehman Medical Institute, Peshawar
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Abstract
Vitamin C has been suggested as beneficial in preventing and curing the common cold, decreasing the incidence of preterm delivery and preeclampsia, decreasing risk of cancer and cardiovascular disease, and improving the quality of life by inhibiting blindness and dementia. In this article, we review the hypothesized mechanisms of these purported health benefits and the evidence behind such claims.
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Schättin A, Baur K, Stutz J, Wolf P, de Bruin ED. Effects of Physical Exercise Combined with Nutritional Supplements on Aging Brain Related Structures and Functions: A Systematic Review. Front Aging Neurosci 2016; 8:161. [PMID: 27458371 PMCID: PMC4933713 DOI: 10.3389/fnagi.2016.00161] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 06/20/2016] [Indexed: 01/12/2023] Open
Abstract
Age-related decline in gray and white brain matter goes together with cognitive depletion. To influence cognitive functioning in elderly, several types of physical exercise and nutritional intervention have been performed. This paper systematically reviews the potential additive and complementary effects of nutrition/nutritional supplements and physical exercise on cognition. The search strategy was developed for EMBASE, Medline, PubMed, Cochrane, CINAHL, and PsycInfo databases and focused on the research question: “Is the combination of physical exercise with nutrition/nutritional supplementation more effective than nutrition/nutritional supplementation or physical exercise alone in effecting on brain structure, metabolism, and/or function?” Both mammalian and human studies were included. In humans, randomized controlled trials that evaluated the effects of nutrition/nutritional supplements and physical exercise on cognitive functioning and associated parameters in healthy elderly (>65 years) were included. The systematic search included English and German language literature without any limitation of publication date. The search strategy yielded a total of 3129 references of which 67 studies met the inclusion criteria; 43 human and 24 mammalian, mainly rodent, studies. Three out of 43 human studies investigated a nutrition/physical exercise combination and reported no additive effects. In rodent studies, additive effects were found for docosahexaenoic acid supplementation when combined with physical exercise. Although feasible combinations of physical exercise/nutritional supplements are available for influencing the brain, only a few studies evaluated which possible combinations of nutrition/nutritional supplementation and physical exercise might have an effect on brain structure, metabolism and/or function. The reason for no clear effects of combinatory approaches in humans might be explained by the misfit between the combinations of nutritional methods with the physical interventions in the sense that they were not selected on sharing of similar neuronal mechanisms. Based on the results from this systematic review, future human studies should focus on the combined effect of docosahexaenoic acid supplementation and physical exercise that contains elements of (motor) learning.
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Affiliation(s)
- Alexandra Schättin
- Department of Health Sciences and Technology, Institute of Human Movement Sciences and Sport, Swiss Federal Institute of Technology (ETH Zurich) Zurich, Switzerland
| | - Kilian Baur
- Sensory-Motor Systems Lab, Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH Zurich) Zurich, Switzerland
| | - Jan Stutz
- Department of Health Sciences and Technology, Institute of Human Movement Sciences and Sport, Swiss Federal Institute of Technology (ETH Zurich) Zurich, Switzerland
| | - Peter Wolf
- Sensory-Motor Systems Lab, Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH Zurich) Zurich, Switzerland
| | - Eling D de Bruin
- Department of Health Sciences and Technology, Institute of Human Movement Sciences and Sport, Swiss Federal Institute of Technology (ETH Zurich) Zurich, Switzerland
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Huskisson E, Maggini S, Ruf M. The Influence of Micronutrients on Cognitive Function and Performance. J Int Med Res 2016; 35:1-19. [PMID: 17408051 DOI: 10.1177/147323000703500101] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
There has been much media speculation (often sensationalist and conflicting) regarding the potential influence of micronutrients on cognitive function and performance. Our aim was to identify the micronutrients specifically implicated in cognitive function and to review the literature to identify original sources underlying the media coverage. Literature searches were carried out to identify recent clinical trials, reviews, editorials and meetings describing the biochemical and physiological role of individual micronutrients. No attempt was made to grade the evidence. The searches confirmed that the water-soluble vitamins (B group and C), together with the minerals, calcium, magnesium and zinc, are most relevant to cognitive performance. Clinical evidence revealed that marginal deficiencies of one or more of these micronutrients are not uncommon, even in the developed countries, and that such deficiencies may affect cognitive performance, especially in vulnerable groups such as the elderly and those individuals who are exposed to occupational pressures and a stressful lifestyle.
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Angelo G, Drake VJ, Frei B. Efficacy of Multivitamin/mineral Supplementation to Reduce Chronic Disease Risk: A Critical Review of the Evidence from Observational Studies and Randomized Controlled Trials. Crit Rev Food Sci Nutr 2016; 55:1968-91. [PMID: 24941429 DOI: 10.1080/10408398.2014.912199] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We reviewed recent scientific evidence regarding the effects of multivitamin/mineral (MVM) supplements on risk of chronic diseases, including cancer, cardiovascular disease, and age-related eye diseases. Data from randomized controlled trials (RCTs) and observational, prospective cohort studies were examined. The majority of scientific studies investigating the use of MVM supplements in chronic disease risk reduction reported no significant effect. However, the largest and longest RCT of MVM supplements conducted to date, the Physicians' Health Study II (PHS II), found a modest and significant reduction in total and epithelial cancer incidence in male physicians, consistent with the Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) trial. In addition, PHS II found a modest and significant reduction in the incidence of nuclear cataract, in agreement with several other RCTs and observational, prospective cohort studies. The effects of MVM use on other subtypes of cataract and age-related macular degeneration remain unclear. Neither RCTs nor prospective cohort studies are without their limitations. The placebo-controlled trial design of RCTs may be inadequate for nutrient interventions, and residual confounding, measurement error, and the possibility of reverse causality are inherent to any observational study. National surveys show that micronutrient inadequacies are widespread in the US and that dietary supplements, of which MVMs are the most common type, help fulfill micronutrient requirements in adults and children.
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Affiliation(s)
- Giana Angelo
- a Linus Pauling Institute, Oregon State University , Corvallis , Oregon , USA
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Forbes SC, Holroyd-Leduc JM, Poulin MJ, Hogan DB. Effect of Nutrients, Dietary Supplements and Vitamins on Cognition: a Systematic Review and Meta-Analysis of Randomized Controlled Trials. Can Geriatr J 2015; 18:231-45. [PMID: 26740832 PMCID: PMC4696451 DOI: 10.5770/cgj.18.189] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Background Observational studies have suggested that various nutrients, dietary supplements, and vitamins may delay the onset of age-associated cognitive decline and dementia. We systematically reviewed recent randomized controlled trials investigating the effect of nutritional interventions on cognitive performance in older non-demented adults. Methods We searched MEDLINE, CINAHL, Embase, and the Cochrane Library for articles published between 2003 and 2013. We included randomized trials of ≥ 3 months’ duration that examined the cognitive effects of a nutritional intervention in non-demented adults > 40 years of age. Meta-analyses were done when sufficient trials were available. Results Twenty-four trials met inclusion criteria (six omega-3 fatty acids, seven B vitamins, three vitamin E, eight other interventions). In the meta-analyses, omega-3 fatty acids showed no significant effect on Mini-Mental State Examination (MMSE) scores (four trials, mean difference 0.06, 95% CI −0.08 – 0.19) or digit span forward (three trials, mean difference −0.02, 95% CI −0.30 – 0.25), while B vitamins showed no significant effect on MMSE scores (three trials, mean difference 0.02, 95% CI −0.22 – 0.25). None of the vitamin E studies reported significant effects on cognitive outcomes. Among the other nutritional interventions, statistically significant differences between the intervention and control groups on at least one cognitive domain were found in single studies of green tea extract, Concord grape juice, chromium picolinate, beta-carotene, two different combinations of multiple vitamins, and a dietary approach developed for the control of hypertension. Conclusions Omega-3 fatty acids, B vitamins, and vitamin E supplementation did not affect cognition in non-demented middle-aged and older adults. Other nutritional interventions require further evaluation before their use can be advocated for the prevention of age-associated cognitive decline and dementia.
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Affiliation(s)
- Scott C Forbes
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Calgary, AB
| | - Jayna M Holroyd-Leduc
- Departments of Medicine, Clinical Neurosciences and Community Health Sciences, Faculty of Medicine, University of Calgary, Calgary, AB;; Alberta Seniors Health Strategic Clinical Network, Alberta Health Services, Calgary, AB
| | - Marc J Poulin
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Calgary, AB;; Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, AB
| | - David B Hogan
- Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, AB;; Brenda Stafford Foundation Chair in Geriatric Medicine, Faculty of Medicine, University of Calgary, Calgary, AB;; Departments of Medicine, Clinical Neurosciences and Community Health Sciences, Faculty of Medicine, University of Calgary, Calgary, AB;; Alberta Seniors Health Strategic Clinical Network, Alberta Health Services, Calgary, AB
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Popper CW. Single-micronutrient and broad-spectrum micronutrient approaches for treating mood disorders in youth and adults. Child Adolesc Psychiatr Clin N Am 2014; 23:591-672. [PMID: 24975626 DOI: 10.1016/j.chc.2014.04.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Several different vitamins and minerals appear to be effective augmenting agents for mood-modifying drugs, but are not potent monotherapies in themselves for treating psychiatric disorders. In contrast, broad-spectrum micronutrient interventions appear in early trials to be as effective as psychiatric medications with fewer adverse effects for treating mood disorders, ADHD, aggressivity, and misconduct in youth and adults. Broad-spectrum treatments also may improve stress responses, cognition, and sense of well-being in healthy adults, but have been less well studied in youth. Current clinical data justify an extensive expansion of research on micronutrient mechanisms and treatments in psychiatry.
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Affiliation(s)
- Charles W Popper
- Child and Adolescent Psychiatry, McLean Hospital, Belmont, MA, USA; Harvard Medical School, Boston, MA, USA.
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Johari SM, Shahar S, Ng TP, Rajikan R. A Preliminary Randomized Controlled Trial of Multifaceted Educational Intervention for Mild Cognitive Impairment Among Elderly Malays in Kuala Lumpur. INT J GERONTOL 2014. [DOI: 10.1016/j.ijge.2013.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Engelborghs S, Gilles C, Ivanoiu A, Vandewoude M. Rationale and clinical data supporting nutritional intervention in Alzheimer's disease. Acta Clin Belg 2014; 69:17-24. [PMID: 24635394 DOI: 10.1179/0001551213z.0000000006] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Adequate nutrition plays an important role in the maintenance of cognitive function, particularly during aging. Malnutrition is amongst the risk factors for developing mild cognitive impairment (MCI) and Alzheimer's disease (AD). Epidemiological studies have associated deficiencies in some nutrients with a higher risk of cognitive dysfunction and/or AD. Cognitive decline in AD is correlated with synaptic loss and many of the components required to maintain optimal synaptic function are derived from dietary sources. As synapses are part of the neuronal membrane and are continuously being remodelled, the availability of sufficient levels of nutritional precursors (mainly uridine monophosphate, choline and omega-3 fatty acids) to make the phospholipids required to build neuronal membranes may have beneficial effects on synaptic degeneration in AD. In addition, B-vitamins, phospholipids and other micronutrients act as cofactors to enhance the supply of precursors required to make neuronal membranes and synapses. Despite this, no randomized controlled trial has hitherto provided evidence that any single nutrient has a beneficial effect on cognition or lowers the risk for AD. However, a multi-target approach using combinations of (micro)nutrients might have beneficial effects on cognitive function in neurodegenerative brain disorders like AD leading to synaptic degeneration. Here we review the clinical evidence for supplementation, based on a multi-target approach with a focus on key nutrients with a proposed role in synaptic dysfunction. Based on preclinical evidence, a nutrient mixture, Souvenaid(®) (Nutricia N.V., Zoetermeer, The Netherlands) was developed. Clinical trials with Souvenaid(®) have shown improved memory performance in patients with mild AD. Further clinical trials to evaluate the effects of nutritional intervention in MCI and early dementia due to AD are on-going.
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Grodstein F, O'Brien J, Kang JH, Dushkes R, Cook NR, Okereke O, Manson JE, Glynn RJ, Buring JE, Gaziano M, Sesso HD. Long-term multivitamin supplementation and cognitive function in men: a randomized trial. Ann Intern Med 2013; 159:806-14. [PMID: 24490265 PMCID: PMC3858850 DOI: 10.7326/0003-4819-159-12-201312170-00006] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Despite widespread use of multivitamin supplements, their effect on cognitive health-a critical issue with aging-remains inconclusive. To date, no long-term clinical trials have studied multivitamin use and cognitive decline in older persons. OBJECTIVE To evaluate whether long-term multivitamin supplementation affects cognitive health in later life. DESIGN Randomized, double-blind, placebo-controlled trial of a multivitamin from 1997 to 1 June 2011. The cognitive function substudy began in 1998. Up to 4 repeated cognitive assessments by telephone interview were completed over 12 years. (ClinicalTrials.gov: NCT00270647) SETTING: The Physicians' Health Study II. PATIENTS 5947 male physicians aged 65 years or older. INTERVENTION Daily multivitamin or placebo. MEASUREMENTS A global composite score averaging 5 tests of global cognition, verbal memory, and category fluency. The secondary end point was a verbal memory score combining 4 tests of verbal memory, which is a strong predictor of Alzheimer disease. RESULTS No difference was found in mean cognitive change over time between the multivitamin and placebo groups or in the mean level of cognition at any of the 4 assessments. Specifically, for the global composite score, the mean difference in cognitive change over follow-up was -0.01 SU (95% CI, -0.04 to 0.02 SU) when treatment was compared with placebo. Similarly, cognitive performance did not differ between the multivitamin and placebo groups on the secondary outcome, verbal memory (mean difference in cognitive change over follow-up, -0.005 SU [CI, -0.04 to 0.03 SU]). LIMITATION Doses of vitamins may be too low or the population may be too well-nourished to benefit from a multivitamin. CONCLUSION In male physicians aged 65 years or older, long-term use of a daily multivitamin did not provide cognitive benefits. PRIMARY FUNDING SOURCE National Institutes of Health, BASF, Pfizer, and DSM Nutritional Products.
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Otaegui-Arrazola A, Amiano P, Elbusto A, Urdaneta E, Martínez-Lage P. Diet, cognition, and Alzheimer's disease: food for thought. Eur J Nutr 2013; 53:1-23. [PMID: 23892520 DOI: 10.1007/s00394-013-0561-3] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 07/11/2013] [Indexed: 02/07/2023]
Abstract
INTRODUCTION The prevention of Alzheimer's disease (AD) has become a real challenge due to its rising prevalence and the lack of an effective cure. Diet and nutrients have gained significant interest as potentially modifiable protective factors. PURPOSE The aim of this review is to provide an updated summary of evidence related to the effect of diet and nutritional factors on the risk of AD and cognitive aging, and discuss the potential mechanisms and confounding factors involved. METHODS A search was conducted in Medline and Web of Knowledge for epidemiological and clinical studies in the international literature from January 2000 to February 2013 using combinations of the following keywords: "Alzheimer's disease", "mild cognitive impairment", "cognitive function", "dietary factors", "omega-3", "antioxidants", "B vitamins", "dietary patterns", and "Mediterranean diet". RESULTS AND CONCLUSION Data from observational studies point to a protective role for certain nutrients, such as omega-3 fatty acids, antioxidants or B vitamins, and dietary patterns (Mediterranean diet). However, data from randomized controlled trials do not show a consistent effect. Whether confounding factors such as age, disease stage, other dietary components, cooking processes, and other methodological issues explain the divergent results remains to be established. Moreover, if certain nutrients protect against dementia, it is as yet unknown whether they may have a general effect on brain vascular health or directly interfere with the etiopathogenesis of AD.
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Affiliation(s)
- Ane Otaegui-Arrazola
- Department of Neurology, Fundación CITA-alzhéimer Fundazioa, Paseo Mikeletegi 71, Planta 1, 20009, San Sebastián, Guipúzcoa, Spain,
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Harrison FE. A critical review of vitamin C for the prevention of age-related cognitive decline and Alzheimer's disease. J Alzheimers Dis 2012; 29:711-26. [PMID: 22366772 DOI: 10.3233/jad-2012-111853] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Antioxidants in the diet have long been thought to confer some level of protection against the oxidative damage that is involved in the pathology of Alzheimer's disease as well as general cognitive decline in normal aging. Nevertheless, support for this hypothesis in the literature is equivocal. In the case of vitamin C (ascorbic acid) in particular, lack of consideration of some of the specific features of vitamin C metabolism has led to studies in which classification of participants according to vitamin C status is inaccurate, and the absence of critical information precludes the drawing of appropriate conclusions. Vitamin C levels in plasma are not always reported, and estimated daily intake from food diaries may not be accurate or reflect actual plasma values. The ability to transport ingested vitamin C from the intestines into blood is limited by the saturable sodium-dependent vitamin C transporter (SVCT1) and thus very high intakes and the use of supplements are often erroneously considered to be of greater benefit that they really are. The current review documents differences among the studies in terms of vitamin C status of participants. Overall, there is a large body of evidence that maintaining healthy vitamin C levels can have a protective function against age-related cognitive decline and Alzheimer's disease, but avoiding vitamin C deficiency is likely to be more beneficial than taking supplements on top of a normal, healthy diet.
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Affiliation(s)
- Fiona E Harrison
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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Harris E, Macpherson H, Vitetta L, Kirk J, Sali A, Pipingas A. Effects of a multivitamin, mineral and herbal supplement on cognition and blood biomarkers in older men: a randomised, placebo-controlled trial. Hum Psychopharmacol 2012; 27:370-7. [PMID: 22711385 DOI: 10.1002/hup.2236] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 05/09/2012] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Nutritional and vitamin status may be related to cognitive function and decline in older adults. The aim of this study was to investigate the effects of nutritional supplementation on cognition in older men. METHOD The current study was an 8-week, placebo-controlled, double-blind investigation into the effects of a multivitamin, mineral and herbal supplement (Swisse Men's Ultivite®, Swisse Vitamins Pty Ltd, Melbourne, Australia) on cognitive performance in older men. Participants were 51 male individuals aged between 50 and 74 years, with a sedentary lifestyle. Cognitive performance was assessed at baseline and post-treatment using a computerised battery of cognitive tasks, enabling the measurement of a range of attentional and memory processes. Blood measures of vitamin B(12) , folate and homocysteine were collected prior to and after supplementation. RESULTS The results of this study revealed that contextual recognition memory performance was significantly improved following multivitamin supplementation (p < 0.05). Performance on other cognitive tasks did not change. Levels of vitamin B(12) and folate were significantly increased with a concomitant decrease in homocysteine, indicating that relatively short-term supplementation with a multivitamin can benefit these risk factors for cognitive decline. CONCLUSION Findings from this study indicate that daily multivitamin supplementation may improve episodic memory in older men at risk of cognitive decline.
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Affiliation(s)
- Elizabeth Harris
- NICM Collaborative Centre for Neurocognition, Centre for Human Psychopharmacology, Swinburne University, Hawthorn, Victoria, Australia
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Nassiri-Asl M, Sarookhani MR, Abbasi E, Zangivand AA, Shakiba E, Sedighi A, Rahbari M. The effects of pre-treatment with vitamin B6 on memory retrieval in rats. Food Chem 2012. [DOI: 10.1016/j.foodchem.2011.11.095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database Syst Rev 2012; 2012:CD007176. [PMID: 22419320 PMCID: PMC8407395 DOI: 10.1002/14651858.cd007176.pub2] [Citation(s) in RCA: 284] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Our systematic review has demonstrated that antioxidant supplements may increase mortality. We have now updated this review. OBJECTIVES To assess the beneficial and harmful effects of antioxidant supplements for prevention of mortality in adults. SEARCH METHODS We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index Expanded, and Conference Proceedings Citation Index-Science to February 2011. We scanned bibliographies of relevant publications and asked pharmaceutical companies for additional trials. SELECTION CRITERIA We included all primary and secondary prevention randomised clinical trials on antioxidant supplements (beta-carotene, vitamin A, vitamin C, vitamin E, and selenium) versus placebo or no intervention. DATA COLLECTION AND ANALYSIS Three authors extracted data. Random-effects and fixed-effect model meta-analyses were conducted. Risk of bias was considered in order to minimise the risk of systematic errors. Trial sequential analyses were conducted to minimise the risk of random errors. Random-effects model meta-regression analyses were performed to assess sources of intertrial heterogeneity. MAIN RESULTS Seventy-eight randomised trials with 296,707 participants were included. Fifty-six trials including 244,056 participants had low risk of bias. Twenty-six trials included 215,900 healthy participants. Fifty-two trials included 80,807 participants with various diseases in a stable phase. The mean age was 63 years (range 18 to 103 years). The mean proportion of women was 46%. Of the 78 trials, 46 used the parallel-group design, 30 the factorial design, and 2 the cross-over design. All antioxidants were administered orally, either alone or in combination with vitamins, minerals, or other interventions. The duration of supplementation varied from 28 days to 12 years (mean duration 3 years; median duration 2 years). Overall, the antioxidant supplements had no significant effect on mortality in a random-effects model meta-analysis (21,484 dead/183,749 (11.7%) versus 11,479 dead/112,958 (10.2%); 78 trials, relative risk (RR) 1.02, 95% confidence interval (CI) 0.98 to 1.05) but significantly increased mortality in a fixed-effect model (RR 1.03, 95% CI 1.01 to 1.05). Heterogeneity was low with an I(2)- of 12%. In meta-regression analysis, the risk of bias and type of antioxidant supplement were the only significant predictors of intertrial heterogeneity. Meta-regression analysis did not find a significant difference in the estimated intervention effect in the primary prevention and the secondary prevention trials. In the 56 trials with a low risk of bias, the antioxidant supplements significantly increased mortality (18,833 dead/146,320 (12.9%) versus 10,320 dead/97,736 (10.6%); RR 1.04, 95% CI 1.01 to 1.07). This effect was confirmed by trial sequential analysis. Excluding factorial trials with potential confounding showed that 38 trials with low risk of bias demonstrated a significant increase in mortality (2822 dead/26,903 (10.5%) versus 2473 dead/26,052 (9.5%); RR 1.10, 95% CI 1.05 to 1.15). In trials with low risk of bias, beta-carotene (13,202 dead/96,003 (13.8%) versus 8556 dead/77,003 (11.1%); 26 trials, RR 1.05, 95% CI 1.01 to 1.09) and vitamin E (11,689 dead/97,523 (12.0%) versus 7561 dead/73,721 (10.3%); 46 trials, RR 1.03, 95% CI 1.00 to 1.05) significantly increased mortality, whereas vitamin A (3444 dead/24,596 (14.0%) versus 2249 dead/16,548 (13.6%); 12 trials, RR 1.07, 95% CI 0.97 to 1.18), vitamin C (3637 dead/36,659 (9.9%) versus 2717 dead/29,283 (9.3%); 29 trials, RR 1.02, 95% CI 0.98 to 1.07), and selenium (2670 dead/39,779 (6.7%) versus 1468 dead/22,961 (6.4%); 17 trials, RR 0.97, 95% CI 0.91 to 1.03) did not significantly affect mortality. In univariate meta-regression analysis, the dose of vitamin A was significantly associated with increased mortality (RR 1.0006, 95% CI 1.0002 to 1.001, P = 0.002). AUTHORS' CONCLUSIONS We found no evidence to support antioxidant supplements for primary or secondary prevention. Beta-carotene and vitamin E seem to increase mortality, and so may higher doses of vitamin A. Antioxidant supplements need to be considered as medicinal products and should undergo sufficient evaluation before marketing.
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Affiliation(s)
- Goran Bjelakovic
- Department of InternalMedicine,Medical Faculty, University ofNis,Nis, Serbia.
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Macpherson H, Ellis KA, Sali A, Pipingas A. Memory improvements in elderly women following 16 weeks treatment with a combined multivitamin, mineral and herbal supplement: A randomized controlled trial. Psychopharmacology (Berl) 2012; 220:351-65. [PMID: 22006207 DOI: 10.1007/s00213-011-2481-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 08/31/2011] [Indexed: 11/26/2022]
Abstract
RATIONALE There is potential for multivitamin supplementation to improve cognition in the elderly. This randomized, double-blind, placebo-controlled trial was conducted to investigate the effects of 16 weeks multivitamin supplementation (Swisse Women's 50+ Ultivite ®) on cognition in elderly women. METHODS Participants in this study were 56 community dwelling, elderly women, with subjective complaints of memory loss. Cognition was assessed using a computerized battery of memory and attention tasks designed to be sensitive to age-related declines to fluid intelligence, and a measure of verbal recall. Biochemical measures of selected nutrients, homocysteine, markers of inflammation, oxidative stress, and blood safety parameters were also collected. All cognitive and haematological parameters were assessed at baseline and 16 weeks post-treatment. RESULTS The multivitamin improved speed of response on a measure of spatial working memory, however benefits to other cognitive processes were not observed. Multivitamin supplementation decreased levels of homocysteine and increased levels of vitamin B(6) and B(12), with a trend for vitamin E to increase. There were no hepatotoxic effects of the multivitamin formula indicating this supplement was safe for everyday usage in the elderly. CONCLUSION Sixteen weeks ssupplementation with a combined multivitamin, mineral and herbal formula may benefit working memory in elderly women at risk of cognitive decline.
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Affiliation(s)
- Helen Macpherson
- Centre for Human Psychopharmacology, NICM Collaborative Centre for Neurocognition, Swinburne University of Technology, 427-451 Burwood Road, Hawthorn, Melbourne, VIC, 3122, Australia.
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Kesse-Guyot E, Fezeu L, Jeandel C, Ferry M, Andreeva V, Amieva H, Hercberg S, Galan P. French adults' cognitive performance after daily supplementation with antioxidant vitamins and minerals at nutritional doses: a post hoc analysis of the Supplementation in Vitamins and Mineral Antioxidants (SU.VI.MAX) trial. Am J Clin Nutr 2011; 94:892-9. [PMID: 21775560 DOI: 10.3945/ajcn.110.007815] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Antioxidant properties of some vitamins and trace elements may help to prevent cognitive decline. OBJECTIVE The aim of the current study was to estimate the long-term effects of antioxidant nutrient supplementation on the cognitive performance of participants in the Supplementation in Vitamins and Mineral Antioxidants (SU.VI.MAX) study 6 y after the end of the trial. DESIGN This study included 4447 French participants aged 45-60 y who were enrolled in the SU.VI.MAX study (1994-2002), which was a double-blind, placebo-controlled, randomized trial. From 1994 to 2002, participants received daily vitamin C (120 mg), β-carotene (6 mg), vitamin E (30 mg), selenium (100 μg), and zinc (20 mg) in combination or as a placebo. In 2007-2009, the cognitive performance of participants was assessed with 4 neuropsychological tests (6 tasks). Principal components analysis (PCA) was performed to identify cognitive-function summary scores. Associations between antioxidant supplementation and cognitive functions, in the full sample and by subgroups, were estimated through ANOVA and expressed as mean differences and 95% CIs. Subgroup analyses were performed according to baseline characteristics. RESULTS Subjects receiving active antioxidant supplementation had better episodic memory scores (mean difference: 0.61; 95% CI: 0.02, 1.20). PCA indicated 2 factors that were interpreted as showing verbal memory and executive functioning. Verbal memory was improved by antioxidant supplementation only in subjects who were nonsmokers or who had low serum vitamin C concentrations at baseline. CONCLUSION This study supports the role of an adequate antioxidant nutrient status in the preservation of verbal memory under certain conditions. This trial was registered at clinicaltrials.gov as NCT00272428.
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Affiliation(s)
- Emmanuelle Kesse-Guyot
- Unité de Recherche en Epidémiologie Nutritionnelle, U Institut National de la Santeacute et de la Recherche Meacutedicale, Université Paris, Bobigny, France
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de Wilde MC, Kamphuis PJGH, Sijben JWC, Scheltens P. Utility of imaging for nutritional intervention studies in Alzheimer's disease. Eur J Pharmacol 2011; 668 Suppl 1:S59-69. [PMID: 21816137 DOI: 10.1016/j.ejphar.2011.07.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 07/01/2011] [Accepted: 07/07/2011] [Indexed: 11/24/2022]
Abstract
Alzheimer's disease (AD) is a multi-factorial neurodegenerative disorder and the leading cause of dementia, wherein synapse loss is the strongest structural correlate with cognitive impairment. Basic research has shown that dietary supply of precursors and co-factors for synthesis of neuronal membranes enhances the formation of synapses. Daily intake of a medical food containing a mix of these nutrients for 12 weeks in humans improved memory, measured as immediate and delayed verbal recall by the Wechsler Memory Scale-revised, in patients with very mild AD (MMSE 24-26). An improvement of immediate verbal recall was noted following 24 weeks of intervention in an exploratory extension of the study. These data suggest that the intervention may improve synaptic formation and function in early AD. Here we review emerging technologies that help identify changes in pathological hallmarks in AD, including synaptic function and loss of connectivity in the early stages of AD, before cognitive and behavioural symptoms are observable. These techniques include the detection of specific biomarkers in the cerebrospinal fluid, as well as imaging procedures such as fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), amyloid PET, structural/functional magnetic resonance imaging, diffusion tensor imaging, magnetoencephalography (MEG) and electroencephalography (EEG). Such techniques can provide new insights into the functional and structural changes in the brain over time, and may therefore help to develop more effective AD therapies. In particular, nutritional intervention studies that target synapse formation and function may benefit from these techniques, especially FDG-PET and EEG/MEG employed in the preclinical or early stages of the disease.
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Affiliation(s)
- Martijn C de Wilde
- Nutricia Advanced Medical Nutrition, Danone Research, Centre for Specialised Nutrition, Wageningen, The Netherlands
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McNeill G, Jia X, Whalley LJ, Fox HC, Corley J, Gow AJ, Brett CE, Starr JM, Deary IJ. Antioxidant and B vitamin intake in relation to cognitive function in later life in the Lothian Birth Cohort 1936. Eur J Clin Nutr 2011; 65:619-26. [PMID: 21346712 DOI: 10.1038/ejcn.2011.2] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 10/07/2010] [Accepted: 11/30/2010] [Indexed: 11/09/2022]
Abstract
BACKGROUND/OBJECTIVES Cross-sectional and longitudinal studies provide some evidence for an association between intake of antioxidants and B vitamins, and cognitive function in later life, but intervention studies have not provided clear evidence of beneficial effects. The possibility that those with higher cognitive ability during earlier adult life consume more nutrient-rich diets in later life could provide an alternative explanation for the associations seen in observational studies. METHODS Survey of 1091 men and women born in 1936 living in Edinburgh, Scotland, in whom previous cognitive ability was available from intelligence quotient (IQ) measurements at age 11 years. At age 70 years, participants carried out a range of cognitive tests and completed a semiquantitative food-frequency questionnaire (FFQ). RESULTS A total of 882 participants returned completed FFQs from which intake of β-carotene, vitamin C, B12, folate and riboflavin was estimated. IQ at age 11 years was positively associated with dietary intake of vitamin C (P=0.048) and inversely associated with dietary intake of riboflavin (P<0.001) at age 70 years, and was higher in those taking folate supplements at age 70 years (P<0.005). Weak associations between intake of vitamins B12, C, riboflavin and folate and cognitive performance at age 70 years were attenuated by adjustment for confounding variables, including IQ at age 11 years. In the fully adjusted models, the proportion of total variance in cognitive function at age 70 years accounted for by intake of these nutrients was less than 1%. CONCLUSION These results provide no evidence for a clinically significant beneficial association between intake of these antioxidants and B vitamins, and cognitive function at age 70 years.
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Affiliation(s)
- G McNeill
- Public Health Nutrition Research Group, Population Health Section, Institute of Applied Health Sciences, University of Aberdeen, Aberdeen, UK.
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McCracken C. Challenges of long-term nutrition intervention studies on cognition: discordance between observational and intervention studies of vitamin B12 and cognition. Nutr Rev 2010; 68 Suppl 1:S11-5. [DOI: 10.1111/j.1753-4887.2010.00325.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Ligthart SA, Moll van Charante EP, Van Gool WA, Richard E. Treatment of cardiovascular risk factors to prevent cognitive decline and dementia: a systematic review. Vasc Health Risk Manag 2010; 6:775-85. [PMID: 20859546 PMCID: PMC2941788 DOI: 10.2147/vhrm.s7343] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Indexed: 12/15/2022] Open
Abstract
Background: Over the last decade, evidence has accumulated that vascular risk factors increase the risk of Alzheimer disease (AD). So far, few randomized controlled trials have focused on lowering the vascular risk profile to prevent or postpone cognitive decline or dementia. Objective: To systematically perform a review of randomized controlled trials (RCTs) evaluating drug treatment effects for cardiovascular risk factors on the incidence of dementia or cognitive decline. Selection criteria: RCTs studying the effect of treating hypertension, dyslipidemia, hyperhomocysteinemia, obesity, or diabetes mellitus (DM) on cognitive decline or dementia, with a minimum follow-up of 1 year in elderly populations. Outcome measure: Cognitive decline or incident dementia. Main results: In the identified studies, dementia was never the primary outcome. Statins (2 studies) and intensified control of type II DM (1 study) appear to have no effect on prevention of cognitive decline. Studies on treatment of obesity are lacking, and the results of lowering homocysteine (6 studies) are inconclusive. There is some evidence of a preventive effect of antihypertensive medication (6 studies), but results are inconsistent. Conclusion: The evidence of a preventive treatment effect aimed at vascular risk factors on cognitive decline and dementia in later life is scarce and mostly based on secondary outcome parameters. Several important sources of bias such as differential dropout may importantly affect interpretation of trial results.
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Affiliation(s)
- Suzanne A Ligthart
- Department of General Practice, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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Cognitive tests used in chronic adult human randomised controlled trial micronutrient and phytochemical intervention studies. Nutr Res Rev 2010; 23:200-29. [DOI: 10.1017/s0954422410000119] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In recent years there has been a rapid growth of interest in exploring the relationship between nutritional therapies and the maintenance of cognitive function in adulthood. Emerging evidence reveals an increasingly complex picture with respect to the benefits of various food constituents on learning, memory and psychomotor function in adults. However, to date, there has been little consensus in human studies on the range of cognitive domains to be tested or the particular tests to be employed. To illustrate the potential difficulties that this poses, we conducted a systematic review of existing human adult randomised controlled trial (RCT) studies that have investigated the effects of 24 d to 36 months of supplementation with flavonoids and micronutrients on cognitive performance. There were thirty-nine studies employing a total of 121 different cognitive tasks that met the criteria for inclusion. Results showed that less than half of these studies reported positive effects of treatment, with some important cognitive domains either under-represented or not explored at all. Although there was some evidence of sensitivity to nutritional supplementation in a number of domains (for example, executive function, spatial working memory), interpretation is currently difficult given the prevailing ‘scattergun approach’ for selecting cognitive tests. Specifically, the practice means that it is often difficult to distinguish between a boundary condition for a particular nutrient and a lack of task sensitivity. We argue that for significant future progress to be made, researchers need to pay much closer attention to existing human RCT and animal data, as well as to more basic issues surrounding task sensitivity, statistical power and type I error.
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von Arnim CAF, Gola U, Biesalski HK. More than the sum of its parts? Nutrition in Alzheimer's disease. Nutrition 2010; 26:694-700. [PMID: 20381316 DOI: 10.1016/j.nut.2009.11.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Revised: 10/23/2009] [Accepted: 11/05/2009] [Indexed: 01/16/2023]
Abstract
The aim of this article is to emphasize the importance of malnutrition and micronutrient deficiencies in Alzheimer's disease and discuss recent supplementation trials. Alzheimer's disease (AD) is a devastating neurodegenerative disease with increasing socio-economic impact. It leads to cognitive decline over the years, finally resulting in brain atrophy and gradually destroying a person's ability to learn, reason, make judgments, and communicate. Most of the cases are sporadic and risk factors evolve. There is evidence that malnutrition, oxidative stress, and homocysteine-related vitamins play a role in the pathogenesis of AD. A plethora of epidemiologic studies have explored the associations between nutrients and AD. In addition, more and more data from recent trials are evolving to analyze the impact of micronutrient supplementation in AD and incipient AD concerning B vitamin status and antioxidants. Available data do not support definitive conclusions regarding specific recommendations on micronutrient supplementation for the prevention or treatment of AD; however, more data from prospective trials are needed. Approaches with multiple nutritional components might be promising.
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Aparicio Vizuete A, Robles F, Rodríguez-Rodríguez E, López-Sobaler AM, Ortega RM. Association between food and nutrient intakes and cognitive capacity in a group of institutionalized elderly people. Eur J Nutr 2009; 49:293-300. [PMID: 20013126 DOI: 10.1007/s00394-009-0086-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Accepted: 11/24/2009] [Indexed: 11/25/2022]
Abstract
BACKGROUND Some authors have indicated that the cognitive decline may be due to an inadequate nutritional status. AIM OF STUDY To determine the association between food and nutrient intakes and cognitive capacity score in a group of institutionalized elderly people. METHODS The study subjects were 178 elderly (> or = 65 years of age) institutionalized people from the Madrid region. The diets of these subjects were recorded using the precise weighing method over a 7-day period, and their cognitive capacity assessed using the Short Portable Mental Status Questionnaire (SPMSQ). Subjects were grouped into those who did not incur errors (SPMSQ = 0) and who incurred one or more errors (SPMSQ > 0). Since an association was seen between the SPMSQ test score and age (r = 0.2030; p < 0.01), the subjects were also grouped according to whether they were above or below the percentile 50 (P(50)) for this variable (83 years). RESULTS The subjects with no errors in the SPMSQ test (32%) consumed greater quantities of cereals, eggs, oils, and fats. After adjusting for energy intake and educational level an inverse association was seen between fish and vegetable consumption and cognitive capacity score. In addition, these subjects had greater intakes of carbohydrates, polyunsaturated fatty acids, riboflavin, and vitamins C, D, and E. After adjusting for energy intake, a negative relationship was found between cognitive capacity score and the intake of fibre, vitamin B(6), and folic acid. CONCLUSION In general, the subjects of our study showed an adequate mental capacity, but those who made no errors in the SPMSQ test had more satisfactory diets. This shows the importance of the diet in the maintenance of cognitive function.
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Manders M, De Groot LCPGM, Hoefnagels WHL, Dhonukshe-Rutten RAM, Wouters-Wesseling W, Mulders AJMJ, Van Staveren WA. The effect of a nutrient dense drink on mental and physical function in institutionalized elderly people. J Nutr Health Aging 2009; 13:760-7. [PMID: 19812865 DOI: 10.1007/s12603-009-0211-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To determine whether in the current study the supply of a nutrient dense drink has a positive effect on mental and physical function of institutionalized elderly people. DESIGN A 24-week, randomized, double-blind, placebo-controlled, parallel-group, intervention trial. SETTING Homes for the elderly and nursing homes in the Netherlands. PARTICIPANTS Institutionalized elderly people older than 60 years, with a BMI < or = 30 kg/m2, and a Mini-Mental State Examination score of at least 10 points. INTERVENTION In addition to their usual diet the participants (n=176) received either a nutrient dense drink or a placebo drink twice a day during 24 weeks. MEASUREMENTS The functionality measures included cognitive function, mood, physical performance and the ability to perform activities of daily living. RESULTS In the supplement group a favorable effect of the intervention drink on body weight (1.6 kg difference in change; P = .035), calf circumference (0.9 cm difference in change; P = .048), and blood values (e.g. Hcy decreased from 16.8 to 11.2 mumol/L in the supplement group) was found. In the total group no significant effect was found on functionality outcomes. However, a subgroup of participants with BMI at baseline below 24.4 kg/m2 performed better on the cognitive subscale of Alzheimer's Disease Assessment Scale (P = .09), and its language sub score (P = .01) after 24 weeks of intervention. CONCLUSION The results in the total group of this trial suggest that the nutritional supplement used in this study improves nutritional status. Furthermore, the results of this trial suggest that it is effective as treatment for decreasing function in a subgroup of institutionalized elderly people with low BMI.
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Affiliation(s)
- M Manders
- Division of Human Nutrition, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, the Netherlands
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Vellas B, Andrieu S, Sampaio C, Coley N, Wilcock G. Endpoints for trials in Alzheimer's disease: a European task force consensus. Lancet Neurol 2008; 7:436-50. [PMID: 18420157 DOI: 10.1016/s1474-4422(08)70087-5] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Harmful consequences in health status caused by disease are referred to as outcomes, and in clinical studies the measures of these outcomes are called endpoints. A major challenge when deciding on endpoints is to represent the outcomes of interest accurately, and the accuracy of such representation is assessed through validation. Complex diseases like Alzheimer's disease have many different and interdependent outcomes. We present a consensus for endpoints to be used in clinical trials in Alzheimer's disease, agreed by a European task force under the auspices of the European Alzheimer Disease Consortium. We suggest suitable endpoints for primary and secondary prevention trials, for symptomatic and disease-modifying trials in very early, mild, and moderate Alzheimer's disease, and for trials in severe Alzheimer's disease. A clear and consensual definition of endpoints is crucial for the success of further clinical trials in the field and will allow comparison of data across studies.
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Cognitive and mood effects in healthy children during 12 weeks' supplementation with multi-vitamin/minerals. Br J Nutr 2008; 100:1086-96. [PMID: 18507881 DOI: 10.1017/s0007114508959213] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Adequate levels of vitamins and minerals are essential for optimal neural functioning. A high proportion of individuals, including children, suffer from deficiencies in one or more vitamins or minerals. This study investigated whether daily supplementation with vitamins/minerals could modulate cognitive performance and mood in healthy children. In this randomised, double-blind, placebo-controlled, parallel groups investigation, eighty-one healthy children aged from 8 to 14 years underwent laboratory assessments of their cognitive performance and mood pre-dose and at 1 and 3 h post-dose on the first and last days of 12 weeks' supplementation with a commercially available vitamins/mineral product (Pharmaton Kiddi). Interim assessments were also completed at home after 4 and 8 weeks at 3 h post-dose. Each assessment comprised completion of a cognitive battery, delivered over the Internet, which included tasks assessing mood and the speed and accuracy of attention and aspects of memory (secondary, semantic and spatial working memory). The vitamin/mineral group performed more accurately on two attention tasks: 'Arrows' choice reaction time task at 4 and 8 weeks; 'Arrow Flankers' choice reaction time task at 4, 8 and 12 weeks. A single task outcome (Picture Recognition errors) evinced significant decrements at 12 weeks. Mood was not modulated in any interpretable manner. Whilst it is possible that the significant improvements following treatment were due to non-significant numerical differences in performance at baseline, these results would seem to suggest that vitamin/mineral supplementation has the potential to improve brain function in healthy children. This proposition requires further investigation.
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Coley N, Andrieu S, Gardette V, Gillette-Guyonnet S, Sanz C, Vellas B, Grand A. Dementia Prevention: Methodological Explanations for Inconsistent Results. Epidemiol Rev 2008; 30:35-66. [PMID: 18779228 DOI: 10.1093/epirev/mxn010] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database Syst Rev 2008:CD007176. [PMID: 18425980 DOI: 10.1002/14651858.cd007176] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Animal and physiological research as well as observational studies suggest that antioxidant supplements may improve survival. OBJECTIVES To assess the effect of antioxidant supplements on mortality in primary or secondary prevention randomised clinical trials. SEARCH STRATEGY We searched The Cochrane Library (Issue 3, 2005), MEDLINE (1966 to October 2005), EMBASE (1985 to October 2005), and the Science Citation Index Expanded (1945 to October 2005). We scanned bibliographies of relevant publications and wrote to pharmaceutical companies for additional trials. SELECTION CRITERIA We included all primary and secondary prevention randomised clinical trials on antioxidant supplements (beta-carotene, vitamin A, vitamin C, vitamin E, and selenium) versus placebo or no intervention. Included participants were either healthy (primary prevention trials) or had any disease (secondary prevention trials). DATA COLLECTION AND ANALYSIS Three authors extracted data. Trials with adequate randomisation, blinding, and follow-up were classified as having a low risk of bias. Random-effects and fixed-effect meta-analyses were performed. Random-effects meta-regression analyses were performed to assess sources of intertrial heterogeneity. MAIN RESULTS Sixty-seven randomised trials with 232,550 participants were included. Forty-seven trials including 180,938 participants had low risk of bias. Twenty-one trials included 164,439 healthy participants. Forty-six trials included 68111 participants with various diseases (gastrointestinal, cardiovascular, neurological, ocular, dermatological, rheumatoid, renal, endocrinological, or unspecified). Overall, the antioxidant supplements had no significant effect on mortality in a random-effects meta-analysis (relative risk [RR] 1.02, 95% confidence interval [CI] 0.99 to 1.06), but significantly increased mortality in a fixed-effect model (RR 1.04, 95% CI 1.02 to 1.06). In meta-regression analysis, the risk of bias and type of antioxidant supplement were the only significant predictors of intertrial heterogeneity. In the trials with a low risk of bias, the antioxidant supplements significantly increased mortality (RR 1.05, 95% CI 1.02 to 1.08). When the different antioxidants were assessed separately, analyses including trials with a low risk of bias and excluding selenium trials found significantly increased mortality by vitamin A (RR 1.16, 95% CI 1.10 to 1.24), beta-carotene (RR 1.07, 95% CI 1.02 to 1.11), and vitamin E (RR 1.04, 95% CI 1.01 to 1.07), but no significant detrimental effect of vitamin C (RR 1.06, 95% CI 0.94 to 1.20). Low-bias risk trials on selenium found no significant effect on mortality (RR 0.91, 95% CI 0.76 to 1.09). AUTHORS' CONCLUSIONS We found no evidence to support antioxidant supplements for primary or secondary prevention. Vitamin A, beta-carotene, and vitamin E may increase mortality. Future randomised trials could evaluate the potential effects of vitamin C and selenium for primary and secondary prevention. Such trials should be closely monitored for potential harmful effects. Antioxidant supplements need to be considered medicinal products and should undergo sufficient evaluation before marketing.
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Affiliation(s)
- G Bjelakovic
- Copenhagen University Hospital, Rigshospitalet, Department 3344,Copenhagen Trial Unit, Centre for Clinical Intervention Research, Blegdamsvej 9, Copenhagen, Denmark, DK-2100.
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Kennedy D, Haskell C, Robertson B, Reay J, Brewster-Maund C, Luedemann J, Maggini S, Ruf M, Zangara A, Scholey A. Improved cognitive performance and mental fatigue following a multi-vitamin and mineral supplement with added guaraná (Paullinia cupana). Appetite 2008; 50:506-13. [DOI: 10.1016/j.appet.2007.10.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 10/19/2007] [Accepted: 10/23/2007] [Indexed: 12/28/2022]
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Ancelin ML, Christen Y, Ritchie K. Is antioxidant therapy a viable alternative for mild cognitive impairment? Examination of the evidence. Dement Geriatr Cogn Disord 2007; 24:1-19. [PMID: 17495472 DOI: 10.1159/000102567] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/18/2007] [Indexed: 12/14/2022] Open
Abstract
Therapeutic interventions for the prodromal stages of dementia are currently being sought with a view to delaying if not preventing disease onset. Uncertainty as to whether cognitive disorder in a given individual will progress towards dementia and adverse drug side effects has led to hesitancy on the part of drug regulators to instigate preventive pharmacotherapies. In this context, antioxidant therapies may provide a low-risk alternative, targeting very early biological changes. While a growing body of knowledge demonstrates both the importance of oxidative stress in the aetiology of dementia and the efficacy of antioxidant treatment in animal and cellular models, studies in humans are presently inconclusive. While some antioxidants, notably flavonoid- or vitamin-rich diets, appear to lower the relative risk for Alzheimer's disease in humans in observational studies, these results must be interpreted in the light of the biological complexity of the relationship between oxidative stress and neurodegeneration, and the methodological and theoretical shortcomings of studies conducted to date. A clearer understanding of these factors will assist in the interpretation of the results of the intervention studies which are now being undertaken; these studies being the only current means of establishing efficacy for preventive drug treatment of Alzheimer's disease.
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Sun Y, Lu CJ, Chien KL, Chen ST, Chen RC. Efficacy of Multivitamin Supplementation Containing Vitamins B6 and B12 and Folic Acid as Adjunctive Treatment with a Cholinesterase Inhibitor in Alzheimer's Disease: A 26-Week, Randomized, Double-Blind, Placebo-Controlled Study in Taiwanese Patients. Clin Ther 2007; 29:2204-14. [DOI: 10.1016/j.clinthera.2007.10.012] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2007] [Indexed: 10/22/2022]
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McNeill G, Avenell A, Campbell MK, Cook JA, Hannaford PC, Kilonzo MM, Milne AC, Ramsay CR, Seymour DG, Stephen AI, Vale LD. Effect of multivitamin and multimineral supplementation on cognitive function in men and women aged 65 years and over: a randomised controlled trial. Nutr J 2007; 6:10. [PMID: 17474991 PMCID: PMC1872030 DOI: 10.1186/1475-2891-6-10] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Accepted: 05/02/2007] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Observational studies have frequently reported an association between cognitive function and nutrition in later life but randomised trials of B vitamins and antioxidant supplements have mostly found no beneficial effect. We examined the effect of daily supplementation with 11 vitamins and 5 minerals on cognitive function in older adults to assess the possibility that this could help to prevent cognitive decline. METHODS The study was carried out as part of a randomised double blind placebo controlled trial of micronutrient supplementation based in six primary care health centres in North East Scotland. 910 men and women aged 65 years and over living in the community were recruited and randomised: 456 to active treatment and 454 to placebo. The active treatment consisted of a single tablet containing eleven vitamins and five minerals in amounts ranging from 50-210 % of the UK Reference Nutrient Intake or matching placebo tablet taken daily for 12 months. Digit span forward and verbal fluency tests, which assess immediate memory and executive functioning respectively, were conducted at the start and end of the intervention period. Risk of micronutrient deficiency at baseline was assessed by a simple risk questionnaire. RESULTS For digit span forward there was no evidence of an effect of supplements in all participants or in sub-groups defined by age or risk of deficiency. For verbal fluency there was no evidence of a beneficial effect in the whole study population but there was weak evidence for a beneficial effect of supplementation in the two pre-specified subgroups: in those aged 75 years and over (n 290; mean difference between supplemented and placebo groups 2.8 (95% CI -0.6, 6.2) units) and in those at increased risk of micronutrient deficiency assessed by the risk questionnaire (n 260; mean difference between supplemented and placebo groups 2.5 (95% CI -1.0, 6.1) units). CONCLUSION The results provide no evidence for a beneficial effect of daily multivitamin and multimineral supplements on these domains of cognitive function in community-living people over 65 years. However, the possibility of beneficial effects in older people and those at greater risk of nutritional deficiency deserves further attention.
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Affiliation(s)
- Geraldine McNeill
- Department of Environmental and Occupational Medicine, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Alison Avenell
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Marion K Campbell
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Jonathan A Cook
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Philip C Hannaford
- Department of General Practice and Primary Care, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Mary M Kilonzo
- Health Economics Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Anne C Milne
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Craig R Ramsay
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - D Gwyn Seymour
- Department of Medicine for the Elderly, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Audrey I Stephen
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Luke D Vale
- Health Services Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
- Health Economics Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
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Van Dyk K, Sano M. The impact of nutrition on cognition in the elderly. Neurochem Res 2007; 32:893-904. [PMID: 17342414 DOI: 10.1007/s11064-006-9241-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Accepted: 11/28/2006] [Indexed: 02/07/2023]
Abstract
The possibility that nutritional manipulation may protect against cognitive decline and dementia is an inviting prospect. However data supporting a beneficial effect of a particular dietary pattern is limited. Although studies have demonstrated a health benefit to dietary plans that are high in fiber, whole grains, natural sugar and fish while maintaining lower intake in meat dairy and poultry, the ability to identify the most salient factors of these diets have been unsuccessful. Several aspects of diet have been studied in detail and provided support for potential mechanisms for improving cognition. Clinical trials have explored these mechanisms through supplementation studies with minimal benefits being observed. Continuing work to hone the mechanisms and refine our knowledge of dietary benefits is described.
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Affiliation(s)
- Kathleen Van Dyk
- Department of Psychiatry, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029, USA
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Frick B, Gruber B, Schroecksnadel K, Leblhuber F, Fuchs D. Homocysteine but not neopterin declines in demented patients on B vitamins. J Neural Transm (Vienna) 2006; 113:1815-9. [PMID: 16988797 DOI: 10.1007/s00702-006-0539-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Accepted: 06/18/2006] [Indexed: 10/24/2022]
Abstract
Inflammation and immune system activation seem to play an important role in the development and progression of dementia. Hyperhomocysteinemia is common in various forms of dementia, and a significant relationship was found between concentrations of homocysteine and immune activation marker neopterin. B vitamin supplementation is able to slow-down homocysteine formation in patients. In an open-label study, effects of B vitamin supplementation (Beneuran compositum ) on concentrations of homocysteine and neopterin were investigated in 58 patients with Alzheimer's disease (n=30), vascular dementia (n=12) and mild cognitive impairment (n=16). In all groups of patients, a significant percentage of patients presented with homocysteine concentrations >15 micromol/L and with elevated concentrations of immune activation marker neopterin. Decline of homocysteine concentrations was observed after one month of B vitamin supplementation (all p<0.01; paired Kruskal-Wallisn-test). By contrast, neopterin concentrations remained unchanged (all p>0.05). B vitamin supplementation in patients with various forms of dementia did not influence neopterin concentrations, which indicates that the degree of immune activation and inflammation remained unchanged. The question remains, if lowering of homocysteine by folate supplementation alone could have any beneficial effect to modulate the course of dementia development and if longer period of supplementation would also ameliorate immune system activation status.
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Affiliation(s)
- B Frick
- Division of Biological Chemistry, Biocentre, Innsbruck Medical University, Innsbruck, Austria
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