title: 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.
  
  
  OBJECTIVE
  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.
authors.affiliation: Unit of Nutritional Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden. Electronic address: susanna.larsson@ki.se.
authors.forename: Susanna C
authors.initials: SC
authors.lastname: Larsson
authors.affiliation: Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Nikola
authors.initials: N
authors.lastname: Drca
authors.affiliation: Unit of Nutritional Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Alicja
authors.initials: A
authors.lastname: Wolk
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000009:adverse effects* / Q000453:epidemiology*; D000434:Alcoholic Beverages / Q000009:adverse effects*; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology*; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
keywords: alcohol; atrial fibrillation; meta-analysis; prospective studies; risk factors