Relation of Heavy Alcohol Consumption to QTc Interval Prolongation.

Until now, few studies have examined QT intervals in subjects who consume alcohol. We performed this study to evaluate the associations between alcohol consumption and the QTc interval based on a general population. A total of 11,269 adults were examined using a multistage cluster sampling method to select a representative sample of subjects aged ≥35 years. Participants were asked to provide information about their alcohol consumption, and all participants received electrocardiograms and echocardiograms. A prolonged QTc interval was defined according to the national guidelines, which specify thresholds of ≥460 ms in women and ≥450 ms in men. Patients were divided into 3 categories, based on the amount of alcohol they consumed: heavy drinkers (>15 g/day for women and >30 g/day for men), moderate drinkers (≤15 g/day for women and ≤30 g/day for men), and nondrinkers (0 g/day). The results showed that the heavy drinkers had longer QTc intervals than did the nondrinkers. Multivariate logistic regression analyses revealed that men who were heavy drinkers had approximately 1.4-fold higher odds of having a prolonged QTc interval (odds ratio 1.431, 95% confidence interval [CI] 1.033 to 1.982, p = 0.031) than nondrinkers; in women, heavy drinkers had ∼2.3-fold higher odds of having a prolonged QTc interval (odds ratio 2.344, 95% CI 1.202 to 4.571, p = 0.012) than nondrinkers. Neither men nor women who were moderate drinkers exhibited a significant increase in risk for prolonged QTc interval. In conclusion, heavy alcohol consumption was found to be a risk factor for a prolonged QTc interval.