title: Atrial fibrillation is an independent risk factor for ventricular fibrillation: a large-scale population-based case-control study.
abstract: BACKGROUND
  Atrial fibrillation (AF) is associated with sudden cardiac death. We aimed to study whether AF is associated with ventricular fibrillation (VF), the most common cause of sudden cardiac death and whether this association is independent of confounders, ie, concomitant disease, use of antiarrhythmic or QT-prolonging drugs, and acute myocardial infarction.
  
  
  RESULTS
  We performed a community-based case-control study. Cases were patients with out-of-hospital cardiac arrest because of ECG-documented VF. Controls were age-/sex-matched non-VF subjects from the community. VF risk in AF patients was studied by means of (conditional) logistic regression, adjusting for all available confounders. We studied 1397 VF cases and 3474 controls. AF occurred in 215 cases (15.4%) and 90 controls (2.6%). AF was associated with a 3-fold increased risk of VF (adjusted odds ratio, 3.1 [2.1-4.5]). VF risk in AF cases was increased to the same extent across all age/sex groups and in AF cases who had no comorbidity (adjusted odds ratio 3.0 [1.6-5.5]) or used no confounding drugs (antiarrhythmics, 2.4 [1.4-4.3]; QT-prolonging drugs, 3.1 [1.8-5.4]). VF risk was similarly increased in AF cases with acute myocardial infarction-related VF (adjusted odds ratio 2.6 [1.4-4.8]), and those with non-acute myocardial infarction-related VF (adjusted odds ratio 4.3 [1.9-10.1]).
  
  
  CONCLUSIONS
  AF is independently associated with a 3-fold increased risk of VF. Comorbidity, use of antiarrhythmic or QT-prolonging drugs, or acute myocardial infarction does not fully account for this increased risk.
authors.affiliation: From the Heart Center, Department of Cardiology (A.B., M.T.B., D.A.v.H., H.W.M.v.D., H.L.T.), and Department of General Practice (H.J.B.), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Abdennasser
authors.initials: A
authors.lastname: Bardai
authors.affiliation: From the Heart Center, Department of Cardiology (A.B., M.T.B., D.A.v.H., H.W.M.v.D., H.L.T.), and Department of General Practice (H.J.B.), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Marieke T
authors.initials: MT
authors.lastname: Blom
authors.affiliation: From the Heart Center, Department of Cardiology (A.B., M.T.B., D.A.v.H., H.W.M.v.D., H.L.T.), and Department of General Practice (H.J.B.), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: van Hoeijen
authors.affiliation: From the Heart Center, Department of Cardiology (A.B., M.T.B., D.A.v.H., H.W.M.v.D., H.L.T.), and Department of General Practice (H.J.B.), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Hanneke W M
authors.initials: HW
authors.lastname: van Deutekom
authors.affiliation: From the Heart Center, Department of Cardiology (A.B., M.T.B., D.A.v.H., H.W.M.v.D., H.L.T.), and Department of General Practice (H.J.B.), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Brouwer
authors.affiliation: From the Heart Center, Department of Cardiology (A.B., M.T.B., D.A.v.H., H.W.M.v.D., H.L.T.), and Department of General Practice (H.J.B.), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. h.l.tan@amc.nl.
authors.forename: Hanno L
authors.initials: HL
authors.lastname: Tan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology* / Q000401:mortality; D016022:Case-Control Studies; D015897:Comorbidity; D015986:Confounding Factors, Epidemiologic; D016757:Death, Sudden, Cardiac / Q000453:epidemiology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000453:epidemiology; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D018570:Risk Assessment; D012307:Risk Factors; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality
chemical_list: D000889:Anti-Arrhythmia Agents
keywords: arrhythmias, cardiac; atrial fibrillation; death, sudden, cardiac; ventricular fibrillation