Association of Prior Antithrombotic Drug Use with 90-Day Mortality After Intracerebral Hemorrhage

Purpose: To estimate the strength of association between use of antithrombotics (AT) drugs with survival after spontaneous intracerebral hemorrhage (s-ICH) comparing oral anticoagulant (OAC) or platelet antiaggregants (PA) with no AT use and in active comparator analyses OAC vs PA, direct oral anticoagulant (DOAC) vs vitamin K antagonist (VKA), and clopidogrel vs aspirin.

Patients and methods: We identified patients ≥55 years with a first-ever s-ICH between 2015 and 2018 in Southern Denmark (population 1.2 million). From this population, patients who had used an AT at the time of ICH were identified and classified as OAC or PA vs no AT (reference group), and for active comparator analyses as OAC vs PA (reference group), DOAC vs VKA (reference group), or clopidogrel vs aspirin (reference group). We calculated adjusted relative risks (aRRs) and corresponding [95% confidence intervals] for 90-day all-cause mortality with adjustments for potential confounders.

Results: Among 1043 patients who had s-ICH, 206 had used an OAC, 270 a PA, and 428 had no AT use. The adjusted 90-day mortality was higher in OAC- (aRR 1.68 [1.39-2.02]) and PA-users (aRR 1.21 [1.03-1.42]), compared with no AT. Mortality was higher in OAC- (aRR 1.19 [1.05-1.36]) vs PA-users. In analyses by antithrombotic drug type, 88 used a DOAC, 136 a VKA, 111 clopidogrel, and 177 aspirin. Mortality was lower among DOAC- vs VKA-users (aRR 0.82 [0.68-0.99]), but similar between clopidogrel vs aspirin users (aRR 1.04 [0.87-1.24]).

Conclusion: In this unselected cohort from a geographically defined Danish population, 90-day mortality after s-ICH was higher in patients with prior use of an OAC compared with no AT use or patients using a PA. Mortality was slightly lower for patients using a DOAC than a VKA. Mortality was also higher in PA- vs no AT-users, but there were no differences in mortality between clopidogrel vs aspirin.