Abstract Body (Do not enter title and authors here): Background: Out-of-hospital cardiac arrest (OHCA) continues to have a high mortality with an overall survivability to hospital discharge of less than 10%. Increased bystander cardiopulmonary resuscitation has resulted in better survival after OHCA. Some studies have tackled sociodemographic characteristics and rates of survival, but these are mostly localized studies with varied results. We investigated racial disparities in in-hospital mortality and mechanical circulatory support (MCS) use in OHCA.

Methods: Retrospective cohort study based on the 2019-2020 National Inpatient Sample database of the Healthcare Utilization Project. Our population included patients 18 years or older with out-of-hospital cardiac arrest (OHCA) identified using ICD-10 codes. The primary risk factors examined were race/ethnicity categorized into White, Black, and Hispanic. The primary outcome was in-hospital mortality among patients with OHCA. The secondary outcome was mechanical circulatory support (MCS) use. Left ventricular assist device (LVAD), extracorporeal membrane oxygenation (ECMO), and intra-aortic balloon pump (IABP) were identified as MCS. Multivariate regression analysis was used to estimate the odds ratio.

Results: During the study period, 26,640 hospitalizations with OHCA were identified, of whom 67,4% were White, 22,9% were Black, and 9,7% were Hispanic. The mean (SD) age of patients with OHCA was 65.2 (16) years old, and Black patients well as Hispanic patients had lower mean age compared to White patients (63.1 vs 63 vs 66.3 years old, p<0.001). A total of 19,425 died (72.9%) and 0.9% needed MCS. Notably, more Hispanics needed MCS, compared to White and Black patients (1.7% vs 0.9% vs 0.4%, p=0.049). In the multivariate analysis, we did not find statistical significance among racial/ethnic groups regarding in-hospital mortality. However, Hispanic patients had higher odds of MCS (OR=2.4; CI 95% 1.05-5.55, p=0.039) compared to White patients. No statistical significance was found regarding the use of IABP or LVAD.

Conclusion: Overall, in-hospital mortality was elevated. Moreover, our findings highlight significant racial disparities after OHCA regarding MCS use. More research is needed to identify factors of racial disparities to improve outcomes.