November 28, 2012
Taking Daily Multivitamin Doesn’t Reduce Cardiovascular
Risks for Men

Boston—Taking a daily multivitamin for more than 10 years did not reduce the risk of major cardiovascular events, heart attack, stroke, or death by cardiovascular disease for the nearly 15,000 men participating in the Physicians Health Study (PHS) II.

The study, which appeared this month in The Journal of the American Medical Association, also found no significant effect of a daily multivitamin on rates of congestive heart failure, angina, and coronary revascularization.

Background information in the article suggested that “many U.S. adults take vitamin supplements to prevent chronic diseases or for general health and well-being,” and that those who believe the supplements are beneficial may not engage in as many other preventive health behaviors.

“Although multivitamins are used to prevent vitamin and mineral deficiency, there is a perception that multivitamins may prevent cardiovascular disease (CVD). Observational studies have shown inconsistent associations between regular multivitamin use and CVD, with no long-term clinical trials of multivitamin use,” study authors write.

For the research, Howard D. Sesso, ScD, MPH, of Brigham and Women’s Hospital and Harvard Medical School, and colleagues analyzed data regarding multivitamin use and major cardiovascular events from PHS II, a randomized, placebo-controlled trial that began in 1997 with continued treatment and follow-up through June 1, 2011.

Participants included 14,641 male U.S. physicians initially 50 years of age or older—an average of 64 years. The group was randomly divided between those receiving multivitamins and those getting a placebo. Analysis measured the composite end point of major cardiovascular events, including nonfatal myocardial infarction (MI), nonfatal stroke, and death from CVD. Secondary outcomes included heart attack and stroke individually.

After follow-up at a median of 11.2 years, 1,732 men had major cardiovascular events, including 652 cases (first events) of heart attack and 643 cases of stroke, and 829 men died from cardiovascular disease, with some experiencing multiple events.
Overall, 18.8% (2,727) of the men died during follow-up—1,345 of those taking the multivitamin and 1,412 on the placebo.

Researchers determined there was no significant effect of a daily multivitamin on major cardiovascular events, total MI, total stroke, or CVD mortality. The fewer total deaths among multivitamin users were not statistically significant, they note.

“The PHS II represents to our knowledge the only large-scale, randomized, double-blind, placebo-controlled trial testing the long-term effects of a commonly available multivitamin in the prevention of chronic disease,” the authors write. “These data do not support multivitamin use to prevent CVD, demonstrating the importance of long-term clinical trials of commonly used nutritional supplements.”

In an accompanying editorial, Eva M. Lonn, MD, MSc, of McMaster University and Hamilton General Hospital in Ontario, Canada, suggests multivitamin use can distract from effective CVD prevention, which “is the main hazard of using vitamins and other unproven supplements. The message needs to remain simple and focused: CVD is largely preventable, and this can be achieved by eating healthy foods, exercising regularly, avoiding tobacco products, and, for those with high risk factor levels or previous CVD events, taking proven, safe, and effective medications.”

So, what should pharmacists tell customers who ask whether a multivitamin would benefit them?

“Whether to take a daily multivitamin requires consideration of an individual’s nutritional status, because the aim of supplementation is to prevent vitamin and mineral deficiency, plus consideration of other potential effects, including a modest reduction in cancer and other important outcomes in PHS II that will be reported separately,” study authors add.

U.S. Pharmacist Social Connect