Intracranial hemorrhage mortality in atrial fibrillation patients treated with dabigatran or warfarin.

BACKGROUND AND PURPOSE: In randomized trials, patients with atrial fibrillation (AF) receiving dabigatran, a direct oral anticoagulant, had lower risk of intracranial bleeding (ICB) than those on warfarin. However, concerns exist about potential worse outcomes in dabigatran users if bleeding occurs, given the lack of approved reversal agents. Thus, we examined in-hospital mortality in AF patients with ICB being treated with dabigatran versus warfarin in a real-world population in the United States.

METHODS: We analyzed healthcare utilization claims in the Truven Health Marketscan Research Databases. The study sample included patients with AF admitted to a hospital with a primary diagnosis of ICB. Information on medications, inpatient, and outpatient diagnoses was obtained from available claims. Propensity score-adjusted risk ratios and 95% confidence intervals of in-hospital mortality comparing current users of dabigatran versus warfarin were estimated using relative risk regression.

RESULTS: Among 2391 AF patients admitted with ICB (2290 on warfarin, 101 on dabigatran), 531 died during their admission. In-hospital mortality was similar in those treated with warfarin (22%) or dabigatran (20%). Compared with warfarin users, the propensity score-adjusted risk ratio (95% confidence interval) of mortality in dabigatran users was 0.93 (0.62-1.37). Associations were similar across different ICB subtypes (intracerebral hemorrhage, subarachnoid hemorrhage, and subdural hematoma).

CONCLUSIONS: In this sample of AF patients with ICB on oral anticoagulants, dabigatran was not associated with higher in-hospital mortality compared with warfarin. Hence, reluctance to use dabigatran because of a lack of approved reversal agents is not supported by our results.