Can the flu trigger a heart attack?

A published study now adds a lot more evidence to the notion that flu also raises the risk of heart attacks — a life-threatening connection that was long suspected but never proven.

The study by Canadian researchers, published in the New England Journal of Medicine, examined test results from nearly 20,000 adults in Ontario with lab-confirmed flu between 2009 and 2014 and matched them to hospital records.

That allowed them to see which patients with lab-confirmed flu had heart attacks. They found patients were six-times more likely to suffer a heart attack the week after getting the flu.

“Our findings, combined with previous evidence that influenza vaccination reduces cardiovascular events and mortality, support international guidelines that advocate for influenza immunization in those at high risk of a heart attack,” Dr. Jeff Kwong, lead author of the study, said in a written statement.

Dr. Jason Bowling, an infectious disease specialist with UT Health San Antonio and staff epidemiologist at University Health System, said it underscores how serious influenza can be and why people should take it seriously.

“This is an important study because it reinforces the concern that influenza infection exacerbates underlying medical problems like heart disease, which means it has multiple additional ways of harming people than just the infection alone,” Dr. Bowling said. “In addition to getting the flu vaccine, it is important that people do the important day-to-day recommended care for their medical problems like hypertension and diabetes, which are risk factors for heart disease.”

Who’s most at risk of a heart attack caused by the flu?

The flu causes a lot of inflammation in the body which can be particularly harmful to people who have heart disease, diabetes or compromised immune systems.

You’re more at risk of getting a heart attack caused by the flu if:

  • You are 65 years or older and have heart disease.
  • You have pneumonia or other respiratory illness.
  • You are pregnant.
  • You have other severe health problems.

If you're more at risk for complications from the flu and develop a high fever, muscle pain, cough or other respiratory problems, contact your physician or seek medical help right away.

What’s the best way to prevent the flu?

Fortunately, you can be proactive when it comes to flu prevention. Make sure to do the following to reduce your risk of getting the flu virus and its potential complications - especially if you're in a high-risk group to experience additional problems due to the flu:

  • Avoid contact with sick people.
  • Practice good hygiene.
  • Manage your heart condition with your physician’s help.
  • Seek medical help if you experience flu-like symptoms, and you're in a high-risk group for complications from the flu.

And of course, get a flu shot!

University Health System’s infectious disease specialists are on the forefront of innovative treatments and work closely with doctors in other specialties to provide you with expert medical care. For more information, contact us at 210-358-3710.

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