title: Caffeine and risk of atrial fibrillation or flutter: the Danish Diet, Cancer, and Health Study.
abstract: BACKGROUND
  It is not known whether the consumption of caffeine is associated with excess risk of atrial fibrillation.
  
  
  OBJECTIVE
  We evaluated the risk of atrial fibrillation or flutter in association with daily consumption of caffeine from coffee, tea, cola, cocoa, and chocolate.
  
  
  METHODS
  We prospectively examined the association between the amount of caffeine consumed per day and the risk of atrial fibrillation or flutter among 47 949 participants (x age: 56 y) in the Danish Diet, Cancer, and Health Study. Subjects were followed in the Danish National Registry of Patients and in the Danish Civil Registration System. The consumption of caffeine was analyzed by quintiles with Cox proportional-hazard models.
  
  
  RESULTS
  During follow-up (x: 5.7 y), atrial fibrillation or flutter developed in 555 subjects (373 men and 182 women). When the lowest quintile of caffeine consumption was used as a reference, the adjusted hazard ratios (95% CIs) in quintiles 2, 3, 4, and 5 were 1.12 (0.87, 1.44), 0.85 (0.65, 1.12), 0.92 (0.71, 1.20), and 0.91 (0.70, 1.19), respectively.
  
  
  CONCLUSIONS
  Consumption of caffeine was not associated with risk of atrial fibrillation or flutter.
authors.affiliation: Department of Cardiology, Aarhus Sygehus, Aarhus University Hospital, Aarhus, Denmark. Lars.Frost@as.aaa.dk
authors.forename: Lars
authors.initials: L
authors.lastname: Frost
authors.forename: Peter
authors.initials: P
authors.lastname: Vestergaard
mesh_terms: D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology; D001282:Atrial Flutter / Q000453:epidemiology* / Q000209:etiology; D002099:Cacao / Q000737:chemistry; D002110:Caffeine / Q000008:administration & dosage / Q000009:adverse effects*; D002253:Carbonated Beverages / Q000032:analysis; D003069:Coffee / Q000737:chemistry; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D004034:Diet Surveys; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D013662:Tea / Q000737:chemistry
chemical_list: D003069:Coffee; D013662:Tea; D002110:Caffeine