Background and Purpose- We aimed to compare outcomes of ischemic stroke patients with nonvalvular atrial fibrillation between earlier and later initiation of direct oral anticoagulants (DOACs) after stroke onset. Methods- From data for 1192 nonvalvular atrial fibrillation patients with acute ischemic stroke or transient ischemic attack in a prospective, multicenter, observational study, patients who started DOACs during acute hospitalization were included and divided into 2 groups according to a median day of DOAC initiation after onset. Outcomes included stroke or systemic embolism, major bleeding, and death at 3 months, as well as those at 2 years. Results- DOACs were initiated during acute hospitalization in 499 patients in median 4 (interquartile range, 2-7) days after onset. Thus, 223 patients (median age, 74 [interquartile range, 68-81] years; 78 women) were assigned to the early group (≤3 days) and 276 patients (median age, 75 [interquartile range, 69-82] years; 101 women) to the late (≥4 days) group. The early group had lower baseline National Institutes of Health Stroke Scale score and smaller infarcts than the late group. The rate at which DOAC administration persisted at 2 years was 85.2% overall, excluding patients who died or were lost to follow-up. Multivariable Cox shared frailty models showed comparable hazards between the groups at 2 years for stroke or systemic embolism (hazard ratio, 0.86 [95% CI, 0.47-1.57]), major bleeding (hazard ratio, 1.39 [95% CI, 0.42-4.60]), and death (hazard ratio, 0.61 [95% CI, 0.28-1.33]). Outcome risks at 3 months also did not significantly differ between the groups. Conclusions- Risks for events including stroke or systemic embolism, major bleeding, and death were comparable whether DOACs were started within 3 days or from 4 days or more after the onset of nonvalvular atrial fibrillation-associated ischemic stroke or transient ischemic attack. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01581502.
Keywords: anticoagulants; atrial fibrillation; humans; secondary prevention; stroke.