Abstract 12001: Minimal Impact of Dabigatran on Patient Volume in Two Large Anticoagulation Management Services

Abstract

Introduction: Based on the superior efficacy of dabigatran in stroke prevention for non-valvular atrial fibrillation (SPAF) compared with warfarin, dabigatran was expected to replace warfarin for patients who are warfarin-naïve, difficult to maintain in therapeutic range, have histories of warfarin-related bleeding complications, or are on multiple medications. Hypothesis: We hypothesized that the number of SPAF patients referred to Anticoagulation Management Services (AMS) would decrease and that a majority would switch from warfarin to dabigatran.

Methods: We evaluated the number of SPAF patients referred to 2 large services, AMS-1 and AMS-2, 12 months prior to and after market entry of dabigatran. We also evaluated the number of patients who switched from warfarin to dabigatran.

Results: AMS-1 follows 1,225 SPAF patients with mean CHADS2 and CHADS-VASc scores of 2.0 and 3.5, respectively. AMS-2 follows 1,137 SPAF patients with mean CHADS2 and CHADS-VASc scores of 2.0 and 3.3, respectively. In the 12 months preceding market entry of dabigatran, SPAF patients comprised 537 (31.4%) of the referrals sent to AMS-1 and increased to 793 (32.3%) in the following 12 months. For AMS-2, SPAF patients comprised 617 (30.7%) of referrals before market entry of dabigatran and decreased to 495 (25.2%) of referrals. Thus far, 81 (6.6%) patients from AMS-1 and 44 (3.9%) from AMS-2 have switched from warfarin to dabigatran.

Conclusion: Contrary to our projections, the percent of patients referred to AMS-1 for SPAF has increased in the 12 months after market entry of dabigatran. Although the percent of patients referred to AMS-2 for SPAF has decreased, the change has been minimal. The frequency of transition from warfarin to dabigatran has been far lower than we expected.