In addition, 42% of the participants said that they had a history of hypertension, and 35% had a history of high cholesterol. Almost 6% had a history of diabetes.
At baseline, 5% of the men at a history of cardiovascular disease and 9% had a history of cancer.
The primary end point was major cardiovascular events, including nonfatal myocardial infarction, nonfatal stroke, and cardiovascular mortality. Secondary end points included stroke and MI individually.
Results showed that men who took a daily multivitamin didn’t experience any benefit for the primary end point and secondary end points.
There were 867 major cardiovascular events in the multivitamin group and 856 in the placebo group, or 11.0 and 10.8 events/1,000 person-years, a nonsignificant difference. Likewise, there were no significant differences between groups in total strokes (317 in the multivitamin group and 311 in the placebo group) or cardiovascular deaths (408 and 421, respectively). The results were published simultaneously with the presentation at the meeting (JAMA 2012 Nov. 7;308:1751-60).
The results showed no significant effects on gastrointestinal tract symptoms, fatigue, drowsiness, skin discoloration, and migraine.
The population was relatively well nourished, researchers pointed out, "for which supplementation may offer no additional benefit," they wrote.
Also, behavioral interventions such as exercise and medications such as lipid-lowering therapies can effectively lower the CVD risk and make it difficult for a multivitamin to "meaningfully contribute toward risk reduction," researchers wrote.
They added that there is a need to further understand how essential vitamins and minerals, even at standard levels, may differently interact and influence cardiovascular and cancer mechanisms.
"We’re seeing more and more negative studies," about supplements, said Dr. Harold, highlighting the research’s limited understanding of the agents’ biological impact and pathophysiology.
Howard D. Sesso, Sc.D.
Coinvestigator J. Michael Gaziano, a cardiologist at Brigham and Women’s Hospital, said that he had no problems with his patients taking multivitamins as long as it was to mainly prevent vitamin deficiencies, and for its modest effect in reducing cancer. "But when it comes to preventing heart disease, we don’t have to invest our energy on multivitamins," he said.
Dr. Sesso, who is younger than the study’s cohort, said he did not take multivitamins but kept a good diet and exercised. Dr. Harold said he took multivitamins. Dr. Gaziano said he was trim, had a healthy diet, didn’t smoke, and exercised, but he wouldn’t say whether he took multivitamins. He said he wouldn’t reveal that information until all the data from the Physicians’ Health Study II were published. "I think it’s not unreasonable to take a multivitamin," he said.
Dr. Gaziano reported having received investigator-initiated research funding from the National Institutes of Health, the Veterans Administration, and BASF Corp. He received assistance with the study agents and packaging from BASF and Pfizer. Study packaging was provided by DSM Nutritional Products. Dr. Harold said he had no relevant disclosures. Dr. Sesso received research support from NIH and investigator-initiated grant from BASF. Dr. Lonn reported serving as a consultant to Merck and Servier; providing expert testimony for Merck; receiving grants or grants pending from AstraZeneca, GlaxoSmithKline, and Hoffman-LaRoche; and receiving payment for lectures from Novartis and Merck.