In patients with high-risk ischemic stroke with atrial fibrillation (AF), the use of oral anticoagulation (OAC) therapy following a stroke event is associated with a greater reduction in recurrent stroke risk compared with antiplatelet therapy or no antithrombotic therapy, according to a study published in JAMA Network Open.
Investigators retrospectively reviewed treatment patterns and long-term outcomes in 30,626 patients with ischemic stroke and AF who had these data recorded in 4 Danish healthcare registries. Only patients who had survived to 100 days following discharge were included (N=23,567). The study researchers compared patients by post-stroke therapy received, including OAC therapy (n=8927), antiplatelet therapy only (n=8728), or no antithrombotic therapy (n=5912). The primary outcome included thromboembolic events and bleeding complications during a maximum of 10-year follow-up.
The rates of thromboembolic events for the OAC, antiplatelet, and no antithrombotic therapy groups were 17.5%, 21.2%, and 21.5%, respectively. In addition, the mortality rate in these groups were 72.7%, 86.4%, and 86.2%, respectively. Compared with no antithrombotic therapy, OAC therapy was associated with a significantly lower risk for stroke (adjusted hazard ratio [HR] 0.81; 95% CI, 0.73-0.89) and death (adjusted HR 0.68; 95% CI, 0.65-0.72) during follow-up.
There were no significant differences between individuals on antiplatelet therapy vs individuals on no antithrombotic therapy in terms of thromboembolic events (adjusted HR [aHR] 1.01; 95% CI, 0.92-1.12) or death (aHR 0.95; 95% CI, 0.91-1.00). In addition, there was no difference between post-stroke OAC therapy and post-stroke antithrombotic therapy with regard to long-term bleeding risk (aHR 0.97; 95% CI, 0.86-1.10).
Limitations of this analysis includes its retrospective and observational design as well as the inclusion of all AF types, which may limit the ability to extrapolate findings to specific AF subtypes.
The benefit of OAC therapy in this study suggests “substantial opportunities for improvement of both primary and secondary stroke prevention in intermediate- to high-risk patients with AF.”
Gundlund A, Xian Y, Peterson ED, et al. Prestroke and poststroke antithrombotic therapy in patients with atrial fibrillation results from a nationwide cohort. JAMA Network Open. 2018;1(1):e180171.