Changes in Use of Anticoagulation in Patients with Atrial Fibrillation Within a Primary Care Network Associated with the Introduction of Direct Oral Anticoagulants

Abstract Atrial fibrillation (AF) and the decision to anticoagulate is a common problem faced by primary care physicians. Oral anticoagulation (OAC) is underutilized, despite its clear benefits with regards to stroke prevention. We examined OAC usage between 2010 and 2015, following the introduction of direct oral anticoagulants (DOACs) and specifically assessed whether more patients were anticoagulated over time. The study cohort included adult patients aged 18 and older with AF cared for in a 18-practice primary care network between 2010 and 2015. AF status was assigned each calendar year using a validated electronic health record algorithm. We examined OAC usage over time among all patients with AF, and among patients at high risk of stroke (CHA2 DS2 -VASc ≥ 2). The proportion of the population with AF increased over time (2010: 4920 patients [3.5%], 2015: 6452 patients [4.0%]). There was no increase in the proportion of patients prescribed any OAC treatment from 2010 (57.0%) to 2015 (57.4%) (p=0.41). Similarly, among patients at high risk of stroke, the proportion anticoagulated did not increase over time (2010: 61.1%, 2015: 61.7%, p=0.51). Over the study period, DOAC usage increased from 0.31% of all AF patients in 2010 to 18.3% in 2015 (p