In addition to providing immunity against the flu virus, it seems the seasonal flu vaccine may have the added benefit of reducing the risk of a first-time heart attack in middle-aged and older adults in the year subsequent to inoculation. According to a study published in the Canadian Medical Association Journal, researchers found a 19 percent reduction in the probability of suffering a heart attack in people who received the flu vaccine after accounting for other risk factors such as high blood pressure, diabetes, smoking and family history of heart disease.
The study authors were careful to note that their findings do not prove that the flu shot itself can prevent heart attacks, but that it might just lower the risk. In order to prove a cause-and-effect relationship, a randomized clinical trial in which half of patients with established heart disease receive a flu vaccine would have to be conducted.
Even though ACSH's Dr. Gilbert Ross agrees that such a study could more definitively prove the association — if any — between heart attack risk and flu vaccinations, he worries about its feasibility. “I don’t think that would be an ethical study since we recommend the flu vaccine for everyone, and we shouldn’t be withholding it.”
As ACSH’s Dr. Josh Bloom points out, the reduction in heart attack risk may be because “patients who get flu shots may, and quite likely do, take better care of themselves in general, which is known as the healthy patient effect.”
Whatever the nuances of the study are, Dr. Ross has one simple message: “Get your flu shot, and possibly reduce the risk of a first-time heart attack while you’re at it.”