Vitamin E, vitamin C, beta carotene, and cognitive function among women with or at risk of cardiovascular disease: The Women's Antioxidant and Cardiovascular Study.
BACKGROUND
Cardiovascular factors are associated with cognitive decline. Antioxidants may be beneficial.


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


CONCLUSIONS
Antioxidant supplementation did not slow cognitive change among women with preexisting cardiovascular disease or cardiovascular disease risk factors. A possible late effect of vitamin C or beta carotene among those with low dietary intake on cognition warrants further study.
Kang
Jae Hee
JH
Harvard School of Public Health, Boston, Mass., USA. nhjhk@channing.harvard.edu
Cook
Nancy R
NR
Manson
JoAnn E
JE
Buring
Julie E
JE
Albert
Christine M
CM
Grodstein
Francine
F
D000368:Aged; D000369:Aged, 80 and over; D000975:Antioxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D002318:Cardiovascular Diseases / Q000188:drug therapy / Q000453:epidemiology / Q000517:prevention & control* / Q000523:psychology; D003072:Cognition Disorders / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008569:Memory Disorders / Q000517:prevention & control; D008875:Middle Aged; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D009483:Neuropsychological Tests; D018384:Oxidative Stress; D012307:Risk Factors; D016037:Single-Blind Method; D017211:Treatment Failure; D014810:Vitamin E / Q000008:administration & dosage / Q000627:therapeutic use*; D019207:beta Carotene / Q000008:administration & dosage / Q000627:therapeutic use*
D000975:Antioxidants; D018696:Neuroprotective Agents; D019207:beta Carotene; D014810:Vitamin E; D001205:Ascorbic Acid