2023 Volume 45 Issue 2 Pages 120-124
Background and Purpose: Off-label underdosing and poor adherence to medication have been pointed out as causes of ischemic stroke in patients taking direct-acting oral anticoagulants (DOACs). However, ischemic stroke may occur even in patients with on-label appropriate dosing and good adherence. The aim of this study was to determine the clinical features of ischemic stroke in patients with on-label appropriate dosing and good adherence to DOACs. Methods: Of 2,186 consecutive patients with acute ischemic stroke admitted within 7 days of onset between April 2014 and March 2020, 126 patients with non-valvular atrial fibrillation (NVAF) who developed ischemic stroke despite taking DOACs were studied. Patients were classified into two groups: the appropriate DOAC group (on-label appropriate dosing and good adherence) and the insufficient DOAC group (off-label underdosing or poor adherence). The frequency of embolic sources other than NVAF was compared between the appropriate DOAC group and NVAF patients without anticoagulants (no anticoagulant group). Results: Sixty-four patients were in the appropriate DOAC group and had more potential embolic sources other than NVAF compared to those in the no anticoagulant group (40.6% vs. 18.6%, p=0.0002). Conclusion: In NVAF patients, potential embolic sources other than NVAF may underlie the pathogenesis of ischemic stroke despite taking DOACs with on-label appropriate dosing and good adherence.
