Assessment of dabigatran utilization and prescribing patterns for atrial fibrillation in a physician group practice setting

Abstract

For years, warfarin and aspirin have been standard therapies for prophylaxis of stroke in atrial fibrillation. In late 2010, dabigatran, an oral direct thrombin inhibitor, became available for use in nonvalvular atrial fibrillation. We sought to evaluate utilization and prescribing patterns of dabigatran in a physician group practice setting. We retrospectively collected prescription data from October 2010 to December 2011 including indication of use, dose, renal function, drug interactions, history of warfarin therapy, and risk assessment scores (CHADS2 and HAS-BLED). Off-label use (history of valve disease or no diagnosis of atrial fibrillation) occurred in 20% (n = 34) of 174 patients. Renal function assessed by Cockcroft-Gault equation identified 1 case of contraindicated use and the need for initial renal dose adjustment in approximately 1/2 of the patients with reduced renal function (15-30 ml/min). Review of anticoagulant use revealed 68% of patients (n = 119) previously received warfarin and ultimately 20% of all patients on dabigatran resumed warfarin therapy. A significant increase in the use of permeability glycoprotein inhibitors and proton pump inhibitors after initiating dabigatran was observed. Nearly 10% of patients had a CHADS2 score of 0. For patients receiving novel oral anticoagulants, prospective inclusion in anticoagulation services and guidance from specific "place in therapy" statements have potential to play a large role in maximizing safety while aiding in continued research.