Alcohol consumption and risk of atrial fibrillation: a prospective study and dose-response meta-analysis

Abstract

Background: Although high alcohol consumption has been associated with increased risk of atrial fibrillation (AF), the role of light to moderate drinking remains unclear.

Objectives: The study sought to investigate the association between alcohol consumption and AF risk in a prospective study of Swedish men and women and to conduct a meta-analysis of prospective studies to summarize available evidence.

Methods: We followed 79,019 men and women who, at baseline, were free from AF and had completed a questionnaire about alcohol consumption and other risk factors for chronic diseases. Incident AF cases were ascertained by linkage to the Swedish Inpatient Register. For the meta-analysis, studies were identified by searching PubMed through January 10, 2014, and by reviewing references of pertinent publications. Study-specific relative risks (RRs) were combined using a random effects model.

Results: Over 859,420 person-years of follow-up (1998 to 2009), 7,245 incident AF cases were identified in our own cohort study. The association between alcohol consumption and AF did not differ by sex (p for interaction = 0.74). Compared with current drinkers of <1 drink/week (12 g alcohol/drink), the multivariable RRs of AF were 1.01 (95% confidence interval [CI]: 0.94 to 1.09) for 1 to 6 drinks/week, 1.07 (95% CI: 0.98 to 1.17) for 7 to 14 drinks/week, 1.14 (95% CI: 1.01 to 1.28) for 15 to 21 drinks/week, and 1.39 (95% CI: 1.22 to 1.58) for >21 drinks/week. Results were similar after excluding binge drinkers. In a meta-analysis of 7 prospective studies, including 12,554 AF cases, the RRs were 1.08 (95% CI: 1.06 to 1.10) for 1 drink/day, 1.17 (95% CI: 1.13 to 1.21) for 2 drinks/day, 1.26 (95% CI: 1.19 to 1.33) for 3 drinks/day, 1.36 (95% CI: 1.27 to 1.46) for 4 drinks/day, and 1.47 (95% CI: 1.34 to 1.61) for 5 drinks/day, compared with nondrinkers.

Conclusions: These findings indicate that alcohol consumption, even at moderate intakes, is a risk factor for atrial fibrillation.

Keywords: alcohol; atrial fibrillation; meta-analysis; prospective studies; risk factors.