Atrial fibrillation has always been considered a disease of the elderly, but research is changing that impression as well. Although it’s still true that most people who develop AFib are 65 or older, one study found that younger people are developing the condition in larger numbers — and it’s more serious than was previously thought.

University of Pittsburgh researchers who examined data from 67,000 patients with AFib found that nearly one-quarter were under age 65. These younger patients were also at a higher risk for serious complications including heart failure, stroke, heart attack, and death.

Researchers aren’t certain why younger people are developing this condition, but possible causes include the fact that chronic diseases such as diabetes and high blood pressure are occurring at younger ages because of increasing obesity.

Other factors may include lifestyle, stress, vaping, and respiratory damage due to COVID-19.

It could also be that atrial fibrillation is simply more likely to be diagnosed due to the advent of wearable fitness bands that are programmed to detect health issues, including AFib.