Optimal Timing of Anticoagulant Treatment After Intracerebral Hemorrhage in Patients With Atrial Fibrillation

B oth the prevalence of atrial fibrillation (AF) and oral anti-coagulant treatment after intracerebral hemorrhage (ICH) has increased in recent years. 1 Still, a large proportion of these patients are untreated, reflecting the controversy of the decision. There is emerging evidence of the potential benefits of anti-coagulants in these patients. In a Swedish population-based study, recurrent ischemic events outnumbered recurrent ICH among ICH survivors 6 and ICH in itself has been identified as an independent predictor of thromboembolic events among patients with AF. 7 Two recent, Danish observational studies support the reintro-duction of oral anticoagulants as being associated with a significant reduction of all-cause mortality and ischemic stroke rates. International guidelines highlight the lack of evidence as to whether and when to resume anticoagulant treatment after ICH. The largest retrospective study examining the optimal time window for initiating treatment included 3 tertiary centers and 234 patients with warfarin-associated ICH. Fifty-nine patients resumed anticoagulant treatment, and the study concluded that resumption should be delayed by 10 to 30 weeks to avoid the early high-risk period for recurrent hemorrhage. 12 In contrast, a systematic review detailing 492 patients suggests that anticoagulation in high-risk patients may be restarted 3 days from the time of intracerebral bleedings, but authors emphasize the limitations inherent in the studies analyzed. 13 Using the nationwide Swedish Stroke Register, Riksstroke, we studied the relationship between the timing Background and Purpose—This study aims to provide observational data on the relationship between the timing of antithrombotic treatment and the competing risks of severe thrombotic and hemorrhagic events in a cohort of Swedish patients with atrial fibrillation and intracerebral hemorrhage (ICH). Methods—Patients with atrial fibrillation and a first-ever ICH were identified in the Swedish Stroke Register, Riksstroke, 2005 to 2012. Riksstroke was linked with other national registers to find information on treatment, comorbidity, and outcome. The optimal timing of treatment in patients with low and high thromboembolic risk was described through cumulative incidence functions separately for thrombotic and hemorrhagic events and for the combined end point vascular death or nonfatal stroke. Results—The study included 2619 ICH survivors with atrial fibrillation with 5759 person-years of follow-up. Anticoagulant treatment was associated with a reduced risk of vascular death and nonfatal stroke in high-risk patients with no significantly increased risk of severe hemorrhage. The benefit seemed to be greatest when treatment was started 7 to 8 weeks after ICH. For high-risk women, the total risk …