Haemorrhagic stroke among patients with atrial fibrillation: preceding oral anticoagulation use and 30-day case fatality over 10 years

Abstract

Abstract Background and purpose Oral anticoagulation (OAC) is the cornerstone of thromboprophylaxis in atrial fibrillation (AF) yet complicated by elevated bleeding risk. We examined the temporal evolution of OAC treatment on 30-day fatality in patients with AF and first-ever hemorrhagic stroke (HS). Methods We identified the study population from the nationwide registry-linking Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) study. Patients were eligible if the incident AF was diagnosed between January 2009 and November 2017, with a subsequent first-ever HS (ICD-10 I60* or I61*) recorded in hospital or death registries before December 2018. OAC purchases in the previous 90 days were registered. Results Over the ten-year period, 1,890 patients experienced their first-ever HS (53% women, median age 79.5 [IQR 72.5-85.5]). Of these, 1,039 (55%) had a recent OAC purchase. The 30-day case fatality was 45.4% (n=858, 57% women) and did not vary by prior OAC purchase (warfarin 47%, Non-Vitamin K Antagonist Oral Anticoagulants 41%, none 45%). The proportion of patients without OAC decreased from 67% to 34%, while case fatality increased between 2009 and 2011 from 42% to 54% and then decreased from 54% to 43%. Conclusions Despite the near-doubled proportion of patients with AF exposed to OAC prior to their first-ever HS, their 30-day case fatality rate decreased slightly over 10 years. These results suggest that the recent evolution of OAC treatment is associated with improved outcomes in the AF population.