Alcohol May Raise Risk of Irregular Heart Rhythm
Study Shows Link Between Heavy Drinking and Atrial Fibrillation
By Kelli Miller Stacy
WebMD Health News
Reviewed by Laura J. Martin, MD
glass of beer

Jan. 17, 2011 -- People who regularly drink a lot of alcohol are more likely to develop a life-threatening irregular heart rhythm, called atrial fibrillation, than nondrinkers, according to a new study.

Atrial fibrillation is a common type of irregular heart rhythm. Typically, it causes episodes of very fast, irregular heartbeats, which may or may not cause many symptoms. Atrial fibrillation can cause chest pain, shortness of breath, and increase your risk for heart failure and stroke. 

Drinking more than a moderate amount of alcohol daily (two drinks for men, one for women) greatly increases your risk for atrial fibrillation, scientists report in the Jan. 25 issue of the Journal of the American College of Cardiology. Until now, studies evaluating the link between habitual alcohol use and atrial fibrillation have not provided consistent results.

The findings are based on a review of results from 14 different studies involving 130,820 participants. Researchers only included studies in which the highest alcohol intake category was defined as two or more drinks per day for men, one or more drinks per day for women, and 1.5 or more drinks per day for both men and women. The team then compared the risk of atrial fibrillation in those who drank the most alcohol and in those with drank the least amount of alcohol.
Who’s at Highest Risk for Atrial Fibrillation?

The researchers discovered that the more a person drank, the higher their risk for atrial fibrillation. Specifically, the risk for atrial fibrillation increased 8% for each standard drink containing 10 grams of alcohol. In other words, one drink per day increases your risk of atrial fibrillation by 8% and two drinks per day increases your risk by 16%.

Study participants who drank the most alcohol were 50% more likely to develop atrial fibrillation than those who drank the least.

It's not exactly known how alcohol use leads to atrial fibrillation. Some believe that alcohol itself causes biological changes that affect the heart's ability to maintain a normal rhythm. Others say that long-term, excessive alcohol use is known to lead to heart failure, and that makes irregular heart rhythms more likely.

"Not consuming alcohol at all is the most favorable behavior for avoiding AF [atrial fibrillation]," the researchers write.