New Study Confirms Link Between Influenza And Heart Complications

Findings Underscore Need to Get a Flu Shot Early, Lead Researcher Says.

People with heart disease and those who have had a stroke are at higher risk for developing serious complications from the flu. If you're in that group, it is especially important that you get a flu vaccine every flu season to potentially serious complications.

Among adults hospitalized with flu during recent flu seasons, heart disease was one of the most commonly-occurring chronic conditions—about half of adults hospitalized with flu that season had heart disease. Studies have shown that influenza is associated with an increase in heart attacks and stroke. A 2018 study in the New England Journal of Medicine found that the risk of heart attack was 6 times higher within a week of confirmed flu infection. These findings were most pronounced for older adults and those experiencing their first heart attack.

And most recently, an August 2020 study from the CDC & published in the Annals Of Internal Medicine that looked at more than 80,000 U.S. adults hospitalized with the flu over eight flu seasons (2010-11 through 2017-18) found that sudden, serious heart complications were common and occurred in one out of every eight patients (~12% of patients). Of adults hospitalized with flu, 12% had acute heart complications. Of these, 30% were admitted to the ICU and 7% died while in the hospital. The study found that 5% of patients hospitalized with the flu had a cardiac complication despite having no documented underlying conditions.

"Previous to our study, there had been suggestions between the link, but our study shows just how common it is," said lead author Eric Chow, an infectious-disease fellow at University of Washington School of Medicine, who worked as an epidemic intelligence service officer, or "disease detective," at the Centers for Disease Control and Prevention.

The study underscores the importance of getting a flu shot early. "There are few respiratory viruses we have a vaccine for," he said. "Get a flu shot."

Dr. Mark L. Meyer received his M.D. from the Yale University School of Medicine and his J.D. from Yale Law School. He has a private cardiology practice in Manhattan.