Abstract 12209: Anticoagulation Use and Clinical Outcomes Following Major Bleeding on Dabigatran or Warfarin in Atrial Fibrillation
Introduction: Little is known about the patterns of anticoagulation use and clinical outcomes associated with the resumption of anticoagulation after a major hemorrhage.
Hypothesis: We hypothesized that the discontinuation of anticoagulation would be associated with higher thromboembolic risk but lower risk of recurrent bleeding than the post-hemorrhage resumption of anticoagulation with warfarin or dabigatran.
Methods: Using 2010-2012 Medicare Part D data, we identified atrial fibrillation patients who experienced a major bleeding while using warfarin (n=1135) or dabigatran (n=404) and categorized them by their post-hemorrhage use of anticoagulation. We followed them until a clinical event of ischemic stroke, recurrent hemorrhage, or death through December 31, 2012. We constructed logistic regression models to evaluate factors impacting anticoagulation resumption, and Cox Proportional Hazard models to compare the risk of ischemic stroke, all-cause mortality, and recurrent bleeding between treatment groups.
Results: CHA2DS2-Vasc and HAS-BLED scores did not affect the odds of post-hemorrhage anticoagulation resumption. The odds of resuming anticoagulation decreased however by 11% (95%CI, 4%-18%) and 24% (95%CI, 9%-37%) for every 5 years increase in age for warfarin and dabigatran users, respectively. Resumption of anticoagulation with warfarin (hazard ratio (HR) 0.76; 95%CI, 0.59-0.97) or dabigatran (HR0.66; 95%CI 0.44-0.99) was associated with lower combined risk of ischemic stroke and all-cause mortality than anticoagulation discontinuation. The incidence of recurrent major bleeding was higher for patients who were prescribed warfarin after the bleeding event than for those prescribed dabigatran (HR2.31; 95%CI, 1.19-4.76) or whose anticoagulation ceased (HR1.56; 95%CI, 1.10-2.22), but did not differ between patients restarting dabigatran and those discontinuing anticoagulation.
Conclusions: The benefit/risk ratio of dabigatran among atrial fibrillation patients who have survived a major hemorrhage is superior to that of warfarin and of anticoagulation discontinuation.
Author Disclosures: I. Hernandez: None. Y. Zhang: None. M.M. Brooks: None. P.K. Chin: None. S. Saba: None.
- © 2016 by American Heart Association, Inc.