B-PO04-200 GEOGRAPHIC VARIATION IN ANTICOAGULATION AMONG MEDICARE BENEFICIARIES WITH NON-VALVULAR ATRIAL FIBRILLATION IN THE UNITED STATES

Abstract

Little is known about the geographic variation in oral anticoagulant (OAC) use throughout the United States (US) since the approval of direct oral anticoagulants (DOACs) as safe and effective alternatives to warfarin for the treatment of non-valvular atrial fibrillation (NVAF). Our study evaluates the geographic variation of OAC use among NVAF patients in the US by 3-digit zip code. Patients with NVAF were selected from the US Centers for Medicare & Medicaid Services claims database from January 1, 2013 to December 31, 2016. 12 months of health plan enrollment was required before and after the NVAF diagnosis to evaluate baseline characteristics and outcomes, respectively. OAC treatment was measured among those patients with a CHAD2S2-VASc ≥ 2 during the baseline period. Each patient was assigned to a 3-digit zip code based on their primary residence and geographic variation was visualized using ArcGIS Pro software. Over 2.8 million patients with NVAF were identified, of which 97% were at higher risk for stroke with CHAD2S2-VASc ≥ 2. Among this high-risk group of patients, nationwide, approximately 50% of patients with NVAF were prescribed an OAC, with treatment being most common in the Mountain region of the US (Figure). OAC use varies considerably by 3-digit zip code in the US and almost half of patients with NVAF at high risk were not prescribed an OAC. The additional granularity provided in this analysis may help clinicians and other key decision makers identify regions with undertreatment in order to improve patient outcomes.