The recent availability of Dabigatran ( Pradaxa ), a novel oral anticoagulant, provided a new treatment option for stroke prevention in atrial fibrillation beyond Warfarin ( Coumadin ), the main therapy for years.
Little is known about their real-world comparative effectiveness and safety, even less among patient demographic and clinical subgroups.
Using a cohort of non-valvular atrial fibrillation patients initiating anticoagulation during the period 2010-2012 drawn from a large US database of commercial and Medicare supplement claims, researchers 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 ).
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.
In conclusion, Dabigatran could be a safe and potentially more effective alternative to Warfarin in patients with atrial fibrillation managed in routine practice settings. ( Xagena )
Lauffenburger JC et al, J Am Heart Assoc 2015; Epub ahead of print