Heavy drinkers are at significant risk for atrial fibrillation, a heart condition that can trip off a stroke or heart failure, British researchers warn. The research was presented at the annual meeting of the Heart Rhythm Society, in Denver in May 2007.
“Drinking in moderation . . . is safe and does not significantly increase the chances of developing new atrial fibrillation (AF),” said Dr. Joe Martins, lead author of the study and a cardiologist at the Imperial College, London. “However, drinking in excess of this was strongly associated with an increased probability of developing new AF.”
For this study, patients arriving at an arrhythmia clinic at Charing Cross Hospital with symptoms of a new cardiac arrhythmia were asked about their weekly alcohol consumption.
Participants were grouped according to how much they drank: teetotaler (who abstained completely), moderate drinkers (1-14 units per week for females and one to 21 units for males) and excessive (anything greater than moderate).
Those with confirmed atrial fibrillation were then compared to those without the irregular heart beat.
48% of people in each group were moderate drinkers, suggesting no increase in risk. Excessive drinking, however, was much higher in patients with atrial fibrillation than in patients without (27% versus 17%, respectively).
Heavy drinkers raised their risk of atrial fibrillation by 2% for each additional unit they drank compared to non-drinkers.
It’s not clear how alcohol and rhythm disturbances might be linked.
“Several mechanisms have been suggested from very small studies, including the high adrenaline state of drinking and alcohol withdrawal and impaired vagal heart rate control,” Martins said.
Cutting down on drinking could lower the risk, he said.
“We found that nearly one in five of all 984 patients that we evaluated in our study admitted to drinking more than the recommended level,” Martins said. “If this behavior could be modified, one might speculate that it could potentially result in a significant reduction in the number of new AF cases.”
Source: The role of moderate alcohol intake in first detected atrial fibrillation: The Imperial College New AF Study - Joe Martins, M.D., presentation, annual meeting, Heart Rhythm Society, Denver