Abstract TP162: Age, Weight, And Prior Stroke Predicts Ischemic Stroke Despite Direct Acting Oral Anticoagulant Use In Patients With Atrial Fibrillation

Abstract

Introduction: Direct-acting oral anticoagulants (DOACs) and warfarin are standard of care for secondary prevention of ischemic stroke (IS) in persons with atrial fibrillation (AF). However, despite adequate anticoagulation (AC), patients may still experience recurrent IS. We aimed to study the characteristics of patients who developed IS despite therapeutic AC, specifically with DOACs. Methods: Between 2012 and 2021, patients admitted at our hospital with IS despite adequate AC for AF were enrolled. Clinical variables collected included National Institute of Health Stroke Scale (NIHSS), CHA 2 DS 2 -VASc and modified Rankin Score (mRS) at admission. Baseline characteristics were compared between patients taking DOACs and warfarin. Logistic regression analyses were performed to identify predictors of IS in patients using DOACs. Results: A total of 595 patients were included. Of these, 291 patients (48.9%) were on DOACs with a mean age of 75.21 and 43.9% were female. The median CHA 2 DS 2 -VASc and NIHSS score in the DOAC group was 4 and 6, respectively. Compared to those on Warfarin, patients on DOACs were younger (75.21 vs. 78.99 p < 0.001), more likely to be men (55.3% vs. 45.2% p = 0.01) and had higher rates of prior TIA/IS (37.5% vs. 29.3% p = 0.04). Both groups had similar rates of hemorrhagic transformation, but more patients in the DOAC group were on antiplatelet agents concomitantly (21% vs. 6.9% p < 0.001). The most prescribed DOAC was apixaban (66.3%) and cardioembolism was the most common stroke etiology (63.6%), followed by cryptogenic, which was significantly higher in the DOAC group (18.2% vs. 8.3% p = 0.02). Notably, DOAC failure in preventing IS was associated with younger age, overweight/obesity, and prior TIA/IS (Table) . Conclusions: IS despite the use of DOACs is more likely to occur in younger people with prior TIA/IS and obesity. Focusing on preventative strategies and risk factor control for competing mechanisms in this subgroup may help prevent IS recurrence.