Alcohol and atrial fibrillation

Ask the doctor

Q. I started drinking more during the pandemic. But I've heard that alcohol can increase the risk of atrial fibrillation, a condition that my mother already has. How much alcohol is dangerous in terms of atrial fibrillation?

A. We've long known that binge drinking (consuming large amounts of alcohol in a short time period) can trigger a bout of atrial fibrillation, the rapid, irregular heart rhythm commonly known as afib. Doctors refer to this phenomenon as "holiday heart" because they see more cases of it around the holidays, when people are more likely to overindulge in alcohol.

However, growing evidence suggests that in general, the more you drink on a daily basis, the more likely you are to be diagnosed with afib. Even small amounts make a difference. One observational study that tracked people over an average of 14 years found that even a single drink per day — a glass of wine, a beer, or a shot of whiskey, gin, or other spirits — was linked to a 16% higher risk of developing afib compared with not drinking at all.

For people who already have afib, alcohol appears to have a nearly instantaneous effect on their heart rhythm, according to a recent study. People in the study wore heart rate monitors and special ankle sensors to measure their alcohol intake. Researchers found that a single drink doubled the odds of a bout of afib occurring within the next four hours.

In yet another study, researchers created three-dimensional structural maps of the left atrium (one of the two upper chambers of the heart) in people with afib. Compared with light drinkers and nondrinkers, moderate drinkers had more evidence of scarring and electrical signaling problems in their atria. The severity of those problems was directly linked to the severity of afib among the participants.

The bottom line is that even small amounts of alcohol may harm your heart, which is why avoiding alcohol or limiting yourself to an occasional drink on special occasions may be the safest approach. Alcohol use is linked to many other health threats, including car accidents, violence, high blood pressure, and various cancers, and the risks rise in tandem with the amount you drink.

By the way, afib does appear to have a genetic component, although the degree of added risk to family members of people who have afib isn't entirely clear. As for other ways to lower your personal risk, maintaining a healthy weight and getting regular exercise can help.

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