Antithrombotic Treatment and Clinical Outcomes After Intracerebral Hemorrhage: A Retrospective Cohort Study from the Swedish Stroke Register.

Abstract

A rapid shift has occurred from vitamin K antagonists toward direct oral anticoagulants, which have a lower risk of intracerebral hemorrhage (ICH). However, effects on clinical outcomes after ICH are understudied. We aimed to describe the prevalence of antithrombotic drugs and to study the prognosis among prestroke functionally independent Swedish patients with ICH. We identified all patients diagnosed with nontraumatic ICH in 2017 to 2021 from the Swedish Stroke Register (n=13 155) and assessed death and functional outcome at 3 months after ICH in prestroke functionally independent patients (n=10 014). Functional outcome was estimated among 3-month survivors on the basis of self-reported activities of daily living scores. Risks of outcomes were estimated using Poisson regression. In 13 155 patients, 14.5% used direct oral anticoagulant, 10.1% vitamin K antagonists, and 21.6% antiplatelets at ICH onset. Among 10 014 pre-stroke activities of daily living-independent patients, oral anticoagulants and antiplatelets were associated with increased mortality risk (adjusted risk ratio, 1.27 [95% CI, 1.13-1.43]; P<0.001; and adjusted risk ratio, 1.23 [95% CI, 1.13-1.34]; P<0.001 respectively). Mortality risk did not statistically differ between antiplatelets and oral anticoagulants nor between direct oral anticoagulant and vitamin K antagonists. Among 5126 patients with nonmissing functional outcome (69.1% of survivors), antiplatelets (adjusted risk ratio, 1.06 [95% CI, 0.99-1.13]; P=0.100) and oral anticoagulants (adjusted risk ratio, 1.01 [95% CI, 0.92-1.12]; P=0.768) were not statistically significantly associated with functional dependence. There was no statistically significant difference in mortality risk between direct oral anticoagulant and vitamin K antagonists in prestroke functionally independent patients (unadjusted for oral anticoagulant class indication). Furthermore, mortality risk in antiplatelet and oral anticoagulant users might differ less than previously suggested.