Seasonal Flu: Does It Increase The Risk of Heart Attack?

If you’re undecided as to whether to get the seasonal flu vaccine this year, here’s a fact to consider. Getting the flu may increase your risk of dying of a heart attack. Surprised? An association between the common flu virus and heart attack might not seem all that likely, but there’s a growing body of evidence showing that the flu can not only make you feel bad, but can affect the health of your heart as well.  

The Seasonal Flu Virus and Heart Attack Risk: A Study

A study published in the Lancet Infectious Disease journal looked at the association between the seasonal flu virus and risk of heart disease and heart attack. Researchers analyzed forty-two different studies published over a seventy-six year period. They found that deaths related to heart disease and heart attack were up to fifty percent higher during times when the seasonal flu virus was prevalent.  

Why Would the Seasonal Flu Virus Trigger a Heart Attack?

Researchers aren’t sure exactly why, but they have several theories. One is that being infected with the common flu virus sets up an inflammatory reaction which loosens calcified plaques in the coronary arteries and causes clots to form which can lead to a heart attack. The flu virus could also alter the function of the endothelial cells that line the blood vessels which can also damage the heart.

Does Getting Vaccinated Reduce the Risk?

Researchers looked at this issue too, and although the samples were small, they did find a sixty-one percent reduction in deaths from heart attack in those who received the vaccine compared to those who didn’t, but the overall rate of heart attack didn’t appear to be any lower.

The Bottom Line

Does this mean you should go out and get the seasonal flu vaccine to lower your risk of dying of a heart attack? If you have heart disease or a heart attack, it’s probably a good idea as long as you’re not allergic to eggs. Even if you are allergic to eggs, you may still be able to get the flu vaccine if it’s given in graded doses in an allergist’s office. Up to half a million people die of the seasonal flu virus and people who have underlying medical problems such as heart disease are at a higher risk for developing flu related complications.

For people who don’t have heart disease and aren’t at high risk of a heart attack, the answer is less clear. For most people, the risk of having a serious reaction to the flu vaccine is very small and it may be worth having the extra protection when everyone around you is coming down with the flu. Talk to your doctor about what option is best for your particular situation.