Abstract Sun604: Evaluation of Factors Impacting Community Race and Ethnicity Outcome Disparities for Out-of-Hospital Cardiac Arrest Using Mediation Analysis

Background: Out-of-hospital cardiac arrest patient (OHCA) patients from minority communities have worse outcomes, and the factors contributing to this outcome gap are unclear. We utilized mediation analysis to evaluate the impact of different OHCA patient and care characteristics on outcome disparities. Methods: We retrospectively studied the 201-2023 Texas Cardiac Arrest Registry to Enhance Survival. We included adult OHCAs who survived to admission. We excluded OHCAs that occurred in a healthcare facility or were witnessed by 911 witnessed responders. Using census data, we stratified OHCAs into majority race/ethnicity communities; >50% White (majority White), >50% Black (majority Black), and >50% Hispanic/Latino (majority Hispanic/Latino. We calculated hospital survival rates, and stratified hospitals into top (highest survival rate) and bottom (lowest survival rate) performing groups. We defined mediators as age>60, gender, public location, bystander witnessed arrest, initial shockable rhythm, bystander CPR, targeted temperature management, left heart catheterization (LHC), and care at a top performing hospital. We used structural equation modeling and mediation analyses to evaluate the mediation between community race ethnicity, mediators, and outcomes (survival to hospital discharge and survival with favorable neurologic outcome, cerebral performance category of 1 or 2). We calculated mediation proportions for each mediator, the proportion of outcome difference attributed to the mediator. Results: We included 9,195 OHCAs. Patients from Black and Hispanic/Latino communities had worse outcomes. Considering survival to discharge as the outcome, the largest mediators of outcome differences for patients from Black communities compares to White communities were care at a top performing hospitals (30.0%), direct effect (25.7%), LHC (20.7%), and initial shockable rhythm (19.4%). The largest mediators of outcome differences for patients from Hispanic/Latino communities were care at a top performing hospital (32.4%), direct effect (29.9%), initial shockable rhythm (18.8%), and LHC (16.4%). Bystander CPR was not a significant mediator of outcome disparities. Results were similar when survival with a favorable neurologic outcome was defined as the outcome. Conclusion: We identified care at a top performing hospital, LHC, and initial shockable rhythm to be the largest mediators of community race/ethnicity disparities.