Vitamin E supplementation does not appear to confer a benefit in cognitive decline in women after 10 years, results of a randomized, double-blind, placebo-controlled study show.
These results, based on an analysis of data from the Women's Health Study, found no significant cognitive differences in 6,377 women at least 65 years of age who alternated taking 600 IU vitamin E and 100 mg low-dose aspirin every other day or placebo. The subjects initially were evaluated 5.6 years after randomization and at a follow-up visit an average of 4 years later (Arch. Intern. Med. 2006;166:2462–8).
Verbal memory, Telephone Interview of Cognitive Status scores, and category fluency (which reflects executive retrieval functions) were also not significantly different between groups at the follow-up analysis, noted Dr. Jae Hee Kang of the Brigham and Women's Hospital in Boston, and colleagues in their report.
Changes in cognitive function over time also were similar with vitamin E and placebo, though vitamin E was associated with a 15% lower risk of substantial verbal memory decline that reached borderline statistical significance.
Women who exercised less than once a week did gain slightly more benefit from vitamin E in terms of cognitive decline. However, the investigators found that women who exercised at least once per week had no mean change in global cognitive score, and thus, no benefit from vitamin E could be detected.
Vitamin E also proved more beneficial in women without diabetes than in women with diabetes.
The investigators suggested that a longer duration might be needed to show a cognitive benefit with vitamin E, though they noted that other studies have failed to show such a benefit.