American health experts question study about vaccine's benefit for preventing heart attacks

Share this content:

A recent British study that finds an association between a flu shot and a lower risk of heart attack is getting some flak from scientists in the United States.

Some cardiologists and other healthcare experts in the U.S. say the study's findings are flawed. The study, published Monday in the Canadian Medical Association Journal, actually showed that 19% fewer heart attack patients had been vaccinated in the previous year—not that there was a 19% reduction in the rate of heart attacks among adults who had been vaccinated, according to Dr. Kirk Garratt, associate director of the division of cardiac intervention at Lenox Hill Hospital in New York City.

The report's author, Dr. A. Niroshan Siriwardena, defended the study, saying that it looked at the likelihood of heart attack in both vaccinated and unvaccinated individuals. He also stressed that the study drew an association between vaccination and heart attack risk, rather than proving cause-and-effect, HealthDay reported. Despite their concerns, critics of the study note that there have long been theories about the association between vaccination and heart attack risk, and that the findings still reinforce the notion that flu vaccines are beneficial.