RODALE NEWS, EMMAUS, PA—Now that the swine flu pandemic is officially behind us, according to the World Health Organization, this flu season is gearing up to be much less dramatic than last year's. But that's no less reason to skip out on getting the seasonal flu vaccine, particularly if you're at risk for heart problems. Doctors have long noticed that heart attacks spike during the winter, and while that may be due in part to all that snow you have to shovel, it's more likely because of the flu.
"Flu is thought to cause an inflammatory process in the blood vessels, particularly in those people who have narrowing of the arteries due to coronary heart disease," says Niroshan Siriwardena, MBBS, PhD, professor of primary and prehospital health care at the University of Lincoln in the U.K. and the author of a new study linking flu vaccinations to a significantly decreased risk of heart attacks. Plaques in the arteries are more likely to rupture when someone contracts the flu, he adds, and that could trigger a heart attack.
THE DETAILS: In his study, which was published in the Canadian Medical Association Journal, Dr. Siriwardena collected information on 78,706 patients, 16,012 of whom had had heart attacks at some point over a six-year period; the remaining 62,694 were randomly selected from a British medical database. Flu-vaccination rates were roughly the same in both the heart attack group and the randomly selected group, hovering around 51 percent. But in both groups, getting a flu vaccination was associated with a 19 percent drop in the risk of having a heart attack; there was no drop in risk for people who reported receiving a pneumonia vaccine.
The authors also found that when people received the vaccine made a big difference in their risk. People who got the vaccine early in the flu season (usually around September and October) saw a 21 percent reduction in their heart attack risk, while those who got it around November saw just a 12 percent drop in risk.