Abstract P272: Baseline Diet and Long-term Efficacy of a Multivitamin Supplement on Cardiovascular Disease in The Physicians’ Health Study Ii - A Randomized Controlled Trial
Background: Many in the US population take a multivitamin supplement to improve or maintain health however, evidence for long-term health benefits remains scarce. The Physicians’ Health Study II (PHS II) is the only randomized trial investigating the effect from a common multivitamin in men, for which no effect was seen on cardiovascular disease (CVD). An important consideration is the modifying role of baseline nutritional status, as a multivitamin may be more or less efficacious to those with extreme nutritional intake.
Hypothesis: Baseline nutritional status modifies the effect of a multivitamin on the risk of CVD.
Methods: The PHS II is a randomized, double-blind, placebo-controlled trial evaluating the effects of a multivitamin (Centrum Silver or placebo daily) including 14,641 men aged ≥50 years. Baseline diet was assessed through a 116-item food frequency questionnaire among 13,316 men (91%). We tested the interaction between the randomized multivitamin and tertiles of each dietary factor (Alternate Healthy Eating Index, Alternate Mediterranean Diet score, vitamin B6, B12, folate, vitamin C, calcium, and magnesium) as well as the trend in HRs across tertiles.
Results: During an average 11.2 years of follow-up, there were 1487 cases of CVD, 586 cases of myocardial infarction (MI), 559 cases of total stroke, 626 CVD death, and 2086 total deaths. There was no consistent evidence for effect modification by dietary factors. Vitamin B6 modified the effect of multivitamin use on MI (P, interaction=0.01) with an increased risk among men in lowest tertile and decreased risk in highest tertile. The effect on CVD death was modified by vitamin B12 intake with a nonsignificant decreased risk only among men in the lowest tertile, with similar effects noted for total mortality (P, interaction=0.04).
Conclusion: For the majority of dietary factors, there was no evidence that the effect of multivitamin use on major CVD and associated endpoints is modified by individual baseline dietary factors in middle-aged and older male physicians.
Author Disclosures: S. Rautiainen: None. J. Gaziano: B. Research Grant; Significant; Pfizer, Inc, Council for Responsible Nutrition Foundation. W.G. Christen: None. R.J. Glynn: None. J.E. Manson: C. Other Research Support; Modest; Mars, Inc. C. Other Research Support; Significant; Pfizer, Inc.. J.E. Buring: None. H.D. Sesso: B. Research Grant; Significant; Pfizer, Inc., Council for Responsible Nutrition Foundation. C. Other Research Support; Modest; Mars, Inc.
- © 2016 by American Heart Association, Inc.