A retrospective cohort study of Danish patients with AF, with a prestroke CHA2DS2-VASc score of 1 or higher for men and 2 or higher for women, and presenting with
ischemic stroke was conducted from January 1, 2004, to January 31, 2017. Data on hospital admission, prescription fillings, and vital status were assessed using several Danish nationwide registries.
Exposures: Patients who survived 100 days after discharge were divided into 3 groups according to poststroke antithrombotic
therapy: oral anticoagulation (OAC)
therapy, antiplatelet
therapy alone, or no antithrombotic
therapy.
Main Outcomes and Measures: Among 30 626 patients with AF admitted with
ischemic stroke, 11 139 patients (36.3%) received OAC
therapy (44.3% female; median age, 79 years [interquartile range, 73-85 years]), 11 874 (38.8%) received antiplatelet
therapy alone (55.0% female; median age, 82 years [interquartile range, 75-88 years]), and 7613 (24.9%) received no antithrombotic
therapy before
stroke (53.8% female; median age, 80 years [interquartile range, 71-86 years]). Following
stroke, 31.3% of those receiving antiplatelet
therapy alone and 43.7% of those receiving no antithrombotic
therapy before
stroke shifted to OAC
therapy. Yet, 37.5% of patients with
stroke did not receive OAC
therapy following
stroke. However, OAC treatment rates increased over time. During a maximum of 10 years of follow-up, 17.5%, 21.2%, and 21.5% experienced a new thromboembolic event and 72.7%, 86.4%, and 86.2% died among those treated with OAC
therapy, antiplatelet
therapy, or no antithrombotic
therapy, respectively. Poststroke OAC
therapy was associated with lower risk of recurrent thromboembolic events (adjusted hazard ratio, 0.81; 95% CI, 0.73-0.89) and no significant difference in
bleeding complications (adjusted hazard ratio, 0.97; 95% CI, 0.86-1.10), compared with no poststroke antithrombotic
therapy. In contrast, there were no significant differences for those treated with poststroke antiplatelet
therapy and no antithrombotic
therapy.
Conclusions and Relevance: Patients with AF receiving poststroke OAC
therapy had lower risk of recurrent thromboembolic events. Our findings suggest a substantial opportunity for improving primary and secondary
stroke prophylaxis in high-risk patients with AF.