Daily multivitamin didn’t preserve cognitive function

Daily multivitamins didn’t slow age-related cognitive decline, according to a multiyear, placebo-controlled study of almost 6,000 elderly male physicians.

“We saw no benefit of a daily multivitamin in slowing cognitive decline after more than a decade of treatment and follow-up. Long-term use of a daily multivitamin did not provide cognitive benefits,” concluded investigators led by both of Brigham and Women’s Hospital, Boston.

As part of the Physician’s Health Study II, 2,980 male physicians at least 65 years old were randomized to daily and 2,967 others to placebo. The groups had no significant differences in alcohol use, smoking, cardiovascular disease, diabetes, hypertension, hypercholesterolemia, exercise, or depression. The mean age at enrollment in both groups was about 72 years.

The men then took the East Boston Memory Test, the Telephone Interview for Cognitive Status (TICS), and other validated tests from which global composite and verbal memory scores were calculated. Testing was repeated three more times over an average duration of 8.5 years.

The researchers found no significant differences between the two groups over time in cognitive function change. During the follow-up period, the average difference in change between the multivitamin and placebo groups was -0.01 standard units for the global composite score and for the verbal memory score. At each follow-up assessment, there were no differences between the mean global composite and verbal memory scores.

Likewise, multivitamins had no protective effect in sub-analyses based on smoking, alcohol intake, body mass index, diabetes, hypertension, hypercholesterolemia, diet, or depression.

About 84 percent of patients in both groups reported taking at least two-thirds of their study pills. Overall, there was a mean yearly drop of 0.16 points on the 50-point TICS scale.

A limitation of this study is that our population of male physician participants may have been too well nourished to observe benefits of supplementation. In addition, it is possible that effects of multivitamins could have been different in a study population with varying educational attainments.

Previous studies of multivitamins and cognition have not shown benefits in patients who are well nourished.