title: A trial of B vitamins and cognitive function among women at high risk of cardiovascular disease.
abstract: BACKGROUND
  High homocysteine concentrations may be neurotoxic and contribute to cognitive decline in older persons.
  
  
  OBJECTIVE
  The objective was to examine the effect of supplementation with folic acid, vitamin B-12, and vitamin B-6 on cognitive change in women with cardiovascular disease (CVD) or CVD risk factors.
  
  
  METHODS
  The Women's Antioxidant and Folic Acid Cardiovascular Study is a randomized placebo-controlled trial designed to test the effect of a combination of B vitamins (2.5 mg folic acid/d, 50 mg vitamin B-6/d, and 1 mg vitamin B-12/d) on secondary prevention of CVD. Female health professionals aged >or=40 y (n = 5442) with CVD or >or=3 coronary risk factors in 1998 (after folic acid fortification began in the United States) were randomly assigned to treatment. Shortly after randomization (mean: 1.2 y), a substudy of cognitive function was initiated among 2009 participants aged >or=65 y. Telephone cognitive function testing was administered up to 4 times over 5.4 y with 5 tests of general cognition, verbal memory, and category fluency. Repeated-measures analyses were conducted, and the primary outcome was a global composite score averaging all test results.
  
  
  RESULTS
  Mean cognitive change from baseline did not differ between the B vitamin and placebo groups (difference in change in global score: 0.03; 95% CI: -0.03, 0.08; P = 0.30). However, supplementation appeared to preserve cognition among women with a low baseline dietary intake of B vitamins.
  
  
  CONCLUSIONS
  Combined B vitamin supplementation did not delay cognitive decline among women with CVD or CVD risk factors. The possible cognitive benefits of supplementation among women with a low dietary intake of B vitamins warrant further study.
authors.affiliation: Channing Laboratory, Boston, MA 02115, USA. nhjhk@channing.harvard.edu
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Kang
authors.forename: Nancy
authors.initials: N
authors.lastname: Cook
authors.forename: JoAnn
authors.initials: J
authors.lastname: Manson
authors.forename: Julie E
authors.initials: JE
authors.lastname: Buring
authors.forename: Christine M
authors.initials: CM
authors.lastname: Albert
authors.forename: Francine
authors.initials: F
authors.lastname: Grodstein
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology / Q000517:prevention & control*; D016009:Chi-Square Distribution; D003071:Cognition / Q000187:drug effects*; D003072:Cognition Disorders / Q000097:blood / Q000453:epidemiology / Q000517:prevention & control*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage; D005500:Follow-Up Studies; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000150:complications; D011594:Psychometrics; D012307:Risk Factors; D018709:Statistics, Nonparametric; D014805:Vitamin B 12 / Q000008:administration & dosage; D025101:Vitamin B 6 / Q000008:administration & dosage; D014803:Vitamin B Complex / Q000008:administration & dosage*
chemical_list: D006710:Homocysteine; D014803:Vitamin B Complex; D025101:Vitamin B 6; D005492:Folic Acid; D014805:Vitamin B 12