Los Angeles, CA—Taking a multivitamin did not reduce myocardial infarction (MI), stroke, or cardiovascular (CV) death in older men in the first large-scale, long-term randomized controlled trial to address this question to date.
The results of the Randomized Trial of a Multivitamin in the Prevention of a Cardiovascular Disease in Men: The Physicians’ Health Study II (PHS II) were presented at the 2012 American Heart Association meeting by Howard D. Sesso, ScD, MPH, Associate Epidemiologist, Brigham and Women’s Hospital, and Associate Professor of Medicine, Harvard Medical School, and were published simultaneously (Gaziano JM, et al. JAMA. 2012;308: 1871-1880).
More than 33% of US adults take a multivitamin supplement, spending approximately $5 billion annually, many with the notion that this may improve their CV health, making this an important study question. There is also concern among physicians that patients will take a multivitamin for a perceived CV benefit, but not take their prescribed medications.
Basic research has suggested that some of the components of a multivitamin may reduce the risk of CV disease, but observational studies have not demonstrated an association.
This PHS II study included 14,641 male, mostly white, physicians (aged ≥50 years) in the United States, who were randomized to a multivitamin or to placebo and were followed for a mean of 11.2 years. The adherence ranged from 77% at year 4 to 67% at study end. A total of 2757 deaths occurred during follow-up and 1 major CV event was reported in 1732 participants.
The incidence of the combined primary end point of nonfatal MI, nonfatal stroke, and CV death was similar in both groups. A similar lack of effect was seen for total MI and stroke. A nonsignificant reduction was seen for CV death (hazard ratio [HR], 0.95) and for total mortality (HR, 0.94).
However, there was a 39% reduction in MI death, which had borderline significance (27 events in the active arm, 43 in the placebo arm; P = .048).
The study participants were fairly healthy at the start of the study, and many exercised, took aspirin, and had good diets.
“Except for age, no differences were seen in any subgroup for the effect of the multivitamin on CV events,” said Dr Sesso. In participants aged >70 years, there were fewer primary outcome events, which had a borderline significance (P = .04).
“The main reason for taking a multivitamin still remains to prevent vitamin and mineral deficiency,” said Dr Sesso, “however, the decision to take a multivitamin should also consider its modest beneficial effects on cancer.”