Abstract

Background: Despite anticoagulant therapy, patients with atrial fibrillation are still at high risk of ischemic stroke. This study aimed to determine the effect of known pre-stroke atrial fibrillation on the pre-stroke prescription rate of oral anticoagulants, as well as the factors affecting the prescription.

Methods: This registry-based prospective cohort study included patients with known atrial fibrillation before stroke who were hospitalized between December 1, 2012, to December 31, 2016.We analyzed the use of oral anticoagulants before the onset of index-stroke and stratified patients according to their therapeutic and non-therapeutic anticoagulant status.

Results: Of the 511 acute ischemic stroke patients with atrial fibrillation, 243 (47.6%) were known to have atrial fibrillation before stroke. Only 40 (16.5%) of  243 patients received therapeutic anticoagulation therapy. Patients therapeutic on anticoagulation were more likely to have a lower NIHSS score (7.4 ± 6.6 vs. 10.8 ± 8.4, p = 0.01), shorter length of hospital stay (13.1 ± 9.7 vs. 18.8 ± 13.6, p = 0.01), and higher rates of good functional outcomes at  discharge (40% vs. 25.1%, p = 0.01) and at 90 days (60% vs. 39.4%, p = 0.02). Lower CHA₂DS₂VASc score (3.5 ± 2 vs. 4 ± 1.5, p = 0.01), younger age and male gender were associated with the use of therapeutic anticoagulants before stroke.

Conclusion: In patients with atrial fibrillation, oral anticoagulant therapy after the era of non-vitamin K antagonist oral anticoagulants was still underutilized before the onset of stroke. This underused is associated with increased stroke severity and disability.