title: Effectiveness and safety of dabigatran and warfarin in real-world US patients with non-valvular atrial fibrillation: a retrospective cohort study.
abstract: BACKGROUND
  The recent availability of dabigatran, a novel oral anticoagulant, provided a new treatment option for stroke prevention in atrial fibrillation beyond warfarin, the main therapy for years. Little is known about their real-world comparative effectiveness and safety, even less among patient demographic and clinical subgroups.
  
  
  RESULTS
  Using a cohort of non-valvular AF patients initiating anticoagulation from October 2010 to December 2012 drawn from a large US database of commercial and Medicare supplement claims, we applied propensity score weights to Cox proportional hazards regression to assess the comparative effectiveness and safety of dabigatran versus warfarin. Analyses were repeated among clinical and demographic subgroups using stratum-specific propensity scores as an exploratory analysis. Of the 64 935 patients initiating anticoagulation, 32.5% used dabigatran. Compared with warfarin, dabigatran was associated with a lower risk of ischemic stroke or systemic embolism (composite adjusted Hazard Ratio [aHR], 95% CI: 0.86, 95% CI: 0.79 to 0.93), hemorrhagic stroke (aHR: 0.51, 0.40 to 0.65), and acute myocardial infarction (aHR: 0.88, 95% CI: 0.77 to 0.99), and no relation was seen between dabigatran and the composite harm outcome (aHR: 0.94, 95% CI: 0.87 to 1.01). However, dabigatran was associated with a higher risk of gastrointestinal bleeding (aHR: 1.11, 95% CI: 1.02 to 1.22). Estimates of effectiveness and safety appeared to be mostly similar across subgroups.
  
  
  CONCLUSIONS
  Dabigatran could be a safe and potentially more effective alternative to warfarin in patients with atrial fibrillation managed in routine practice settings.
authors: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC (J.C.L., J.F.F., G.F.).
authors: Julie C
authors: JC
authors: Lauffenburger
authors: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC (J.C.L., J.F.F., G.F.).
authors: Joel F
authors: JF
authors: Farley
authors: Division of Cardiology, School of Medicine, University of North Carolina at Chapel Hill, NC (A.K.G.).
authors: Anil K
authors: AK
authors: Gehi
authors: Division of Practice Advancement and Clinical Education, UNC Eshelman School of Pharmacy, Chapel Hill, NC (D.H.R.).
authors: Denise H
authors: DH
authors: Rhoney
authors: Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, NC (A.B.).
authors: M Alan
authors: MA
authors: Brookhart
authors: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC (J.C.L., J.F.F., G.F.).
authors: Gang
authors: G
authors: Fang
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy*; D000069604:Dabigatran / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000517:prevention & control; D057216:Propensity Score; D012189:Retrospective Studies; D020521:Stroke / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D014481:United States / Q000453:epidemiology; D014859:Warfarin / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D014859:Warfarin; D000069604:Dabigatran
keywords: anticoagulants; atrial fibrillation; dabigatran; novel oral anticoagulants; warfarin