The connection between heart disease and flu


Influenza virus, also known as flu, may not be front-of-mind since the COVID-19 pandemic. But if you have heart disease or a history of stroke, protecting yourself from flu should be a priority.

Influenza can put you at high risk for complications and make you six times more likely to have a heart attack. For adults hospitalized with flu, serious heart complications occur in about one out of every eight patients, with 7% dying because of those complications.

The good news is that the flu vaccination is readily available and many of the standard protections against COVID-19 transmission (mask-wearing, hand-washing, social distancing) are also effective against the spread of flu. You can take additional steps to stay heart healthy during flu season. Here’s what you need to know:

How the flu affects people with heart disease

The body naturally reacts to an influenza infection with an inflammatory response, meant to defend your body from the virus. But the response can cause blood clots, increased blood pressure and even scarring or swelling in the heart. If you have heart disease, fatty deposits called plaque build up in your arteries. The added stress of a virus can cause the plaque to rupture, resulting in heart attack or stroke.

Non-cardiac complications of flu are also concerning. Common conditions associated with flu, like pneumonia or respiratory failure, can affect an irregular heartbeat (arrhythmia) or increase heart failure symptoms. Any changes to an already weakened heart make you more prone to a major cardiac event.

How to protect yourself (and your heart) from flu

About half of all adults hospitalized with flu have heart disease. But if you take the right precautions and preventive steps, you may be able to avoid seasonal flu and the complications that often come with it.

Get the flu shot

The best way to protect yourself from flu is to get the vaccine. It prevents influenza about 40% of the time.

While that may not seem like much, research shows the benefits of the flu shot for people with heart disease also include:

  • 37% less chance of being hospitalized for the flu
  • 50% less chance of having out-of-hospital cardiac arrest for 12 months following the vaccination
  • Effectiveness in preventing heart attack comparable to taking blood pressure medication or stopping smoking
  • Lowered risk of major adverse cardiovascular events like stroke, heart attack and cardiovascular-related death, if you’ve had a cardiac episode in the past year

Avoid contact with sick people and practice good hygiene

When you have heart disease, any respiratory virus can lead to complications. Avoid handshaking and keep your distance from others to avoid droplets spread through coughing or sneezing. Be consistent with washing your hands and use hand sanitizer when washing isn’t an option.

Be proactive about managing heart disease

When your heart is strong, you’ll be more likely to recover from the flu without serious complications. Talk to your cardiologist and primary care physician about a plan for managing heart disease and keeping your heart healthy. Follow through with your doctor’s recommended lifestyle changes and take any prescribed medications.

Don’t dismiss flu symptoms

Talk to your primary care provider right away if you suspect you may have the flu, especially if you are part of a high-risk group. Ignoring the symptoms can delay critical flu treatment to shorten the duration of the virus.

Common symptoms of the flu include:

  • Cough
  • Fatigue
  • Fever/chills
  • Headaches
  • Muscle or body aches
  • Runny or stuffy nose
  • Sore throat

Recommended type of flu vaccine for people with heart disease

There are many types of flu vaccines – some are given as an injection (flu shot) and some are sprayed into the nasal cavity. According to the Centers for Disease Control and Prevention (CDC), people with heart disease should avoid the live attenuated influenza vaccine (LAIV), also known as the nasal spray flu vaccine. The reason is simple: Experts have not yet established the safety and effectiveness of the LAIV in people with heart disease.

A high-dose flu vaccine is also available for people ages 65 and older. It contains four times the antigen (a substance that causes an immune response) as a regular flu shot. However, a recent study found no difference in the benefits associated with high-dose versus standard-dose influenza vaccines for people with heart disease.

When is it too late for the flu shot?

It’s ideal to get your flu vaccination by the end of October. But if influenza viruses are still circulating and the flu vaccine is available after that, it’s not too late to get the shot. Most years, flu activity peaks in January or later. More than half the time, it doesn’t peak until at least February.

Keep in mind, the protection provided by flu vaccines weakens over time, making it important to get the flu shot annually.

Reach out to your primary care physician to make an appointment for your seasonal flu vaccine.