Moderate consumption of alcohol may result in an increased risk of atrial fibrillation among individuals with heart disease and progressive diabetes, according to a study in the Canadian Medical Association Journal (CMAJ).

Dr. Koon Teo from McMaster University in Hamilton Ontario and team explained:

“Moderate to high alcohol intake was associated with an increased incidence of artial fibrillation among people aged 55 or older with cardiovascular disease or diabetes. Among moderate drinkers, the effect of binge drinking on the risk of atrial dibrillation was similar to that of habitual heavy drinking.”

The results of the study were derived from a trial which involved over 30,000 people with a history of cardiovascular disease and advanced diabetes with organ damage. All of the patients were 55 and older and from 40 different countries.

Data was taken from the ONTARGET or TRANSCEND studies, which took place between November 2001 and May 2004, with an additional 56 month follow-up period.

The average age of the individuals involved was 66.4 years and 9,064 of them were women (29.8%). Of all the people in the study, 61.7% reported only have up to 1 drink per week, which is considered low consumption.

In addition, 36.6% of the volunteers reported moderate consumption, while 1.7% reported high consumption (more than 2 drinks every day for women, and more than 3 for men).

The WHO (World Health Organization) says that moderate consumption of alcohol for women is up to 2 drinks a day, and for men, up to 3. Binge drinking is defined as drinking 5 drinks a day for low-, moderate-, and light-level consumers.

Of the binge drinkers in the study, 948 of them were actually in the moderate-consumption group.

The follow up period showed 2,093 new atrial fibrillation cases. The by age- and sex- standardized incidence rate for 1000 persons-years was 14.5 for the low consumption individuals, 17.3 for the moderate consumption people and 20.8 in the high consumption group.

The experts added:

“Because drinking moderate quantities of alcohol was common in our study (36.6% of the participants), our findings suggest that the effect of increased alcohol consumption, even in moderate amounts, on the risk of atrial fibrillation among patients with existing cardiovascular disease may be considerable.”

There is limited evidence from other studies that supports that healthy people who binge drink may have increased atrial fibrillation risk, however, moderate drinking is associated with an increased risk in healthy patients.

“Recommendations about the protective effects of moderate alcohol intake in patients at high risk of cardiovascular disease may need to be tempered with these findings,” the authors concluded.

Written by Christine Kearney