Abstract 11180: Contemporary Evidence on Risk Stratification of Anticoagulated Non-Valvular Atrial Fibrillation Patients Grouped by Cha ₂ D ₂ -vasc Score Levels

Abstract

Introduction: The CHA 2 DS 2 -VASc score is an established tool to determine the risk of stroke among atrial fibrillation (AF) patients. The goal of this retrospective claims analysis is to evaluate the incidence of stroke/systemic embolism (SE) and major bleeding (MB) events among patients with non-valvular AF (NVAF) who initiated an oral anticoagulant (OAC; apixaban, dabigatran, edoxaban, rivaroxaban, or warfarin) relative to their CHA 2 DS 2 -VASc score. Methods: Adult NVAF patients who initiated OACs were identified from 01JAN2013-31MAR2019 using data from five insurance claims databases. Patients were required to have 12 months continuous enrollment prior to index (OAC claim date) and were followed to the earliest of OAC discontinuation, death, disenrollment, or study end. Results were stratified by CHA 2 DS 2 -VASc score on index: low (0 for males and 1 for females), moderate (1 for males and 2 for females), high risk 1 (2-3 for males and 3 for females) and high risk 2 (≥4 for males and females). The incidence rate and cumulative incidence were reported for stroke/SE and MB, defined by hospitalization with a primary diagnosis of the respective outcomes. Results: A total of 1,141,097 NVAF patients were identified including 29,298 low risk, 95,584 moderate risk, 327,766 high risk 1 and 688,449 high risk 2 patients. The median follow-up time for all patients was 160 days. The incidence of stroke/SE and MB was 1.3 and 4.1 per 100 person years, respectively. Cumulative incidence for stoke/SE and MB increased across risk groups (Figure). Significant differences were seen for both stroke/SE and MB, when comparing the high risk 1 or high risk 2 group to the low-risk reference group. Conclusions: Assessing stroke/SE and MB events by CHA 2 DS 2 -VASc risk category demonstrates the differences in the rate of events according to the risk groups and provides insight for anticoagulated NVAF patients with clinical risk factors.