A daily multivitamin has modest impact on memory in older adults (COSMOS-WEB)

Reference

Yeung LK, Alschuler DM, Wall M, et al. Multivitamin supplementation improves memory in older adults: a randomized clinical trial. Am J Clin Nutr 2023:S0002-9165(23)48904-6.

Synopsis

There is remarkably little evidence supporting the value of a daily multivitamin to improve health outcomes; the U.S. Preventive Services Task Force concluded that there was insufficient evidence to recommend for or against them for the prevention of cancer or cardiovascular disease. The COSMOS trial randomized 21,442 adults in a 2 x 2 manner to a cocoa supplement or placebo, and to a multivitamin or placebo. The primary outcomes were the effect on mortality, cardiovascular events, and cancer — and the study found no benefit. This study was a substudy of COSMOS that invited participants to volunteer for a study to evaluate the impact on memory using the ModRey test. Participants were given 20 words over the course of 60 seconds, then asked to write down all the words they could remember immediately and then 15 minutes later. This test was done at baseline and annually for up to 3 years, using a Web-based format. The 3562 volunteers in the modified intention-to-treat analysis (ie, at least one follow-up evaluation) were evenly balanced between those originally randomized to receive a multivitamin or a placebo. The mean age of the participants was 71 years, approximately one-third were men, 93% were white, and about 95% spent at least some time in college — so not a terribly representative group in terms of race or education. Immediate recall improved in both the placebo and multivitamin groups over time but improved slightly more in the multivitamin group (from 7.21 to 8.17 words in the placebo group, and from 7.10 to 8.28 words in the multivitamin group [0.23 more words in the multivitamin group at year 1]). None of the other 9 secondary memory outcomes significantly improved.