Abstract WP223: Race-ethnic Differences in the Impact of Antithrombotic Use on Inpatient Mortality Among Intracerebral Hemorrhage Patients in the Florida Stroke Registry (2013–2024)

Background: The use of anticoagulants and antiplatelets in patients at risk for intracerebral hemorrhage (ICH) is growing. Still, the extent to which their associated mortality risk varies by race-ethnicity remains poorly understood. The objective is to examine the association between race-ethnicity and type of antithrombotic use on inpatient mortality among ICH patients in the Florida Stroke Registry (FSR). Methods: We analyzed 32,036 ICH patients in the FSR (2013–2024). Antithrombotic exposure was categorized as anticoagulant-associated ICH (AA ICH), antiplatelet-only ICH (AP ICH), or non-antithrombotic ICH (NA ICH). Multivariable logistic regression models with hospital-level random effects examined the interaction between race-ethnicity and antithrombotic type on inpatient mortality, adjusted for demographics, clinical severity, and comorbidities. Results: Mean age was 69 years, and 54% were male, 60% were Non-Hispanic (NH) White, 18% NH Black, 16% Hispanic, and 6% Other. AA ICH occurred in 17%, AP ICH in 25%, and NA ICH in 58%. Overall, inpatient mortality was 16% with an unadjusted downward trend observed across all three groups from 2013 to 2024. Throughout the years, inpatient mortality occurred in 20%, 16%, and 16% of AA, AP, and NA ICH, respectively. AA ICH carried the highest adjusted inpatient mortality versus NA ICH among NH Black patients (AOR= 2.01; 95% CI 1.51-2.69). Inpatient mortality for AP ICHs versus NA ICH was also significantly highest among NH Black patients (AOR=1.37; 95% 1.11-1.68). Significant race-antithrombotic interactions were observed across crude and adjusted models (p-interaction