Timing of Treatment Initiation With Oral Anticoagulants for Acute Ischemic Stroke in Patients With Nonvalvular Atrial Fibrillation

Abstract

Background:Only a few studies have addressed the optimal start time for oral anticoagulants (OACs) after acute ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF). The aim of this retrospective study was to analyze the time of OAC administration after stroke onset.

Methods and Results:This study included 300 patients with NVAF who had acute ischemic stroke and were treated with OACs between April 2012 and March 2016. We investigated the time at which OACs were started by anticoagulant type and the relationship between the time of OAC administration and stroke severity (the National Institutes of Health Stroke Scale [NIHSS] score on admission). Of the 300 patients, 114 and 186 patients received warfarin and direct-acting OACs (DOACs), respectively. Patients in the DOAC group had OAC initiated therapy significantly sooner (3 days) than in the warfarin group (7 days; P<0.001). With regard to stroke severity (NIHSS score <8, mild; 8–16, moderate; >16, severe), the median time for starting therapy was 2, 7, and 11 days for mild, moderate, and severe stroke, respectively. Hemorrhagic events occurred in 3 patients in the warfarin group; however, no hemorrhagic events occurred in the DOAC group.

Conclusions:Our study revealed that neurologists began OACs earlier in patients with mild acute cerebral infarction. Even in patients with severe stroke, OACs were started earlier than expected.