Consuming even moderate amounts of alcohol may increase the risk for arrhythmia for those with diabetes or heart disease, according to a new study. The study—published in the Canadian Medical Association Journal—pulled from data of over 30,000 adults in 40 countries (median age 66) from two large research trials studying congestive heart failure and controlling high blood pressure, and followed these subjects for four and a half years. When the researchers compared the data of moderate and heavy drinkers to those who lightly drink, they found higher rates of atrial fibrillation among those who drink more. Atrial fibrillation is the most common form of arrhythmia, and those who suffer from it are at a higher risk of experiencing a stroke. Dr. David Juurlink, an internal medicine specialist in Toronto's Sunnybrook Health Sciences Centre, cautions that this study is limiting in that it only identified associations and does not prove that drinking is the cause of higher rates of atrial fibrillation. However, he agrees moderating booze is safer for those with heart problems. “It's hard to make sweeping pronouncements from a single study, but there is a compelling commonsense argument for moderation, and this study supports that,” he says. “If someone who drinks heavily needs one more reason to cut back, this is it. But as we all know there are plenty of other reasons to moderate one's alcohol intake.”