title: Omega-3 Fatty Acid Status Enhances the Prevention of Cognitive Decline by B Vitamins in Mild Cognitive Impairment.
abstract: A randomized trial (VITACOG) in people with mild cognitive impairment (MCI) found that B vitamin treatment to lower homocysteine slowed the rate of cognitive and clinical decline. We have used data from this trial to see whether baseline omega-3 fatty acid status interacts with the effects of B vitamin treatment. 266 participants with MCI aged ≥70 years were randomized to B vitamins (folic acid, vitamins B6 and B12) or placebo for 2 years. Baseline cognitive test performance, clinical dementia rating (CDR) scale, and plasma concentrations of total homocysteine, total docosahexaenoic and eicosapentaenoic acids (omega-3 fatty acids) were measured. Final scores for verbal delayed recall, global cognition, and CDR sum-of-boxes were better in the B vitamin-treated group according to increasing baseline concentrations of omega-3 fatty acids, whereas scores in the placebo group were similar across these concentrations. Among those with good omega-3 status, 33% of those on B vitamin treatment had global CDR scores >0 compared with 59% among those on placebo. For all three outcome measures, higher concentrations of docosahexaenoic acid alone significantly enhanced the cognitive effects of B vitamins, while eicosapentaenoic acid appeared less effective. When omega-3 fatty acid concentrations are low, B vitamin treatment has no effect on cognitive decline in MCI, but when omega-3 levels are in the upper normal range, B vitamins interact to slow cognitive decline. A clinical trial of B vitamins combined with omega-3 fatty acids is needed to see whether it is possible to slow the conversion from MCI to AD.
authors.affiliation: Institute of Public Health, College of Medicine and Health Sciences, United Arab Emirates University, United Arab Emirates.
authors.forename: Abderrahim
authors.initials: A
authors.lastname: Oulhaj
authors.affiliation: OPTIMA, Department of Pharmacology, University of Oxford, Oxford, UK.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Jernerén
authors.affiliation: OPTIMA, Department of Pharmacology, University of Oxford, Oxford, UK.|Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Helga
authors.initials: H
authors.lastname: Refsum
authors.affiliation: OPTIMA, Department of Pharmacology, University of Oxford, Oxford, UK.
authors.forename: A David
authors.initials: AD
authors.lastname: Smith
authors.affiliation: Division of Geriatric Medicine, Department of Medicine, Faculty of Health Sciences, University of Cape Town, South Africa.
authors.forename: Celeste A
authors.initials: CA
authors.lastname: de Jager
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition / Q000187:drug effects*; D060825:Cognitive Dysfunction / Q000097:blood* / Q000188:drug therapy; D018450:Disease Progression; D015525:Fatty Acids, Omega-3 / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D016896:Treatment Outcome; D014803:Vitamin B Complex / Q000627:therapeutic use*
chemical_list: D015525:Fatty Acids, Omega-3; D014803:Vitamin B Complex
keywords: Alzheimer’s disease; B vitamins; clinical dementia rating scale; cognition; omega–3 fatty acids