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Kang JH, Cook N, Manson J, Buring JE, Albert CM, Grodstein F. A trial of B vitamins and cognitive function among women at high risk of cardiovascular disease. Am J Clin Nutr 88, 1602-1610

Channing Laboratory, Boston, MA 02115, USA.
American Journal of Clinical Nutrition (Impact Factor: 6.92). 01/2009; 88(6):1602-10. DOI: 10.3945/ajcn.2008.26404
Source: PubMed

ABSTRACT High homocysteine concentrations may be neurotoxic and contribute to cognitive decline in older persons.
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.
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.
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.
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.

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Available from: Jae H Kang, Nov 26, 2014
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    • "The authors do not report any data relating to cognitive performance. In one of the longest treatment studies, Kang et al. [39] utilised a placebo-controlled design to investigate the effects of B vitamin supplementation (comprising 2.5 mg B9, 1 mg of B12, and 50 mg of B6) in two thousand and nine elderly (mean age 72 years) women with cardiovascular disease and CVD risk factors (1002 allocated to treatment group) over a five-and-half-year period using a telephone cognitive battery measuring (1) general cognition (Telephone Interview of Cognitive Status (TICS)), (2) verbal memory (delayed recall of the TICS 10-word list and the immediate and delayed recalls of the East Boston Memory Test), and (3) category fluency (asked to name as many animals as possible in 1 minute). Results revealed no effect of treatment. "
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    • "Previous studies of the effect of the main agents on cognitive change found that neither the antioxidant supplementation (Kang et al., 2009) nor the B vitamin supplementation (Kang et al., 2008) was significantly associated with a slowing down of cognitive change in women with preexisting cardiovascular disease or risk factors. "
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