Risk of Stroke and other Thromboembolic Complications after Interruption of DOAC Therapy Compared with Warfarin Therapy in Patients with Atrial Fibrillation: A Retrospective Cohort Analysis

Direct oral anticoagulants (DOACs) have become the treatment of choice in thromboembolism prophylaxis for non-valvular atrial fibrillation, surpassing warfarin. While interruption of DOAC therapy for various reasons is a common eventuality, the body of data from real-world clinical practice on the implications of such interruptions in different clinical settings is still limited. We assessed complication rates from DOAC (apixaban, rivaroxaban, dabigatran) interruption compared with warfarin in hospitalized patients. We performed a retrospective cohort analysis of electronic records of patients hospitalized in Rabin Medical Center between 2010 and 2017. Incidents of anticoagulation interruptions for various reasons (including unintended interruptions) were collected. DOAC-treated patients were excluded if they reported non-compliance, and warfarin-treated patients were excluded if their international normalized ratio measurement on admission was subtherapeutic. Outcomes included ischemic stroke, systemic thromboembolism, myocardial infarction, and all-cause mortality within 90 days of anticoagulation interruption. The median CHA2DS2-VASc score was 5.0 (IQR 4.0-6.0) in both treatment groups. The associated risk of stroke, thromboembolic complications, myocardial infarction, and all-cause mortality after interruption of anticoagulation was not significantly different between the 2 treatment groups. Selective comparison of patients who were well balanced on warfarin before treatment interruption to DOAC-treated patients did not significantly influence the outcomes. This study did not find a significant difference in the complication rate after interruption of DOAC therapy compared with interruption of warfarin therapy in hospitalized patients with a high risk of thromboembolism.