Abstract WP236: Trends in Antithrombotic Therapy Use and Clinical Outcome in Acute Ischemic Stroke and Atrial Fibrillation in a Hispanic Population in the Era of Direct Oral Anticoagulants

Abstract

Introduction and Purpose: Guidelines strongly recommend oral anticoagulation (OAC) for stroke prevention for individuals with atrial fibrillation (AF). Before introduction of direct oral anticoagulants (DOAs) in 2011, we demonstrated that in our Hispanic population most of the patients with AF admitted with an acute stroke were receiving antiplatelets or no antithrombotic therapy. This study examined the trends in antithrombotic use in AF after the introduction of DOAs. Methods: Patients with transient ischemic attack [TIA] and ischemic stroke [IS] enrolled in Mexican national registries of general public hospitals (n=4172) were analyzed to select patients with previous AF (n=534). Hemorrhagic stroke was excluded. Primary end points were (1) to compare pre-stroke antithrombotic treatment between patients who had a stroke from 2002-2010 versus 2011-2018, and (2) to compare short-term outcome regarding pre-stroke treatment and between both time periods. Results: Prevalence of AF was 12.8% (534/4172), age 73.8 ±13.3; 170 (31.8%) had had a previous IS/TIA. CHA 2 DS 2 -VASc 3.89 ±1.8, HAS-BLED 2.3 ± 1.1. When comparing antithrombotic therapy between both time periods we found: no anticoagulant therapy 71.8% vs 66.9%, subtherapeutic levels of those receiving vitamin-K antagonists (VKAs) 20.2% vs 10.5%, therapeutic VKA 8% vs 14.3%, and DOAs use of 14.3% (only last period). OAC effective therapy was lower in patients without previous IS/TIA (9.9% versus 17.1%). Patients using OAC in therapeutic range or DOAs at the time of stroke had better outcome when compared with individuals taking antiplatelets or no antithrombotics (P <0.05). Short-term modified Rankin Scale (mRS) between both time periods were mRS 0-2: 36.9% vs 40.6%, mRs 3-5: 36.4% vs 46.6%, and death 26.7% vs 12.8% ( p = 0.003). Conclusions: In our Hispanic population underuse of effective anticoagulant therapy is still prevalent even in the new DOAs era (more >70%). VKA in therapeutic ranges or DOAs use had less disability and mortality on short-term outcome. There is a low frequency of DOAs in our public general hospital population.