Abstract Su707: Sex Differences in Bystander Cardiopulmonary Resuscitation and Survival to Hospital Discharge for Public Out-of-Hospital Cardiac Arrests in North Carolina and Singapore

Introduction: Although it is known that women are less likely than men to receive bystander cardiopulmonary resuscitation (BCPR) in public, few studies have examined differences in receipt of BCPR and survival to hospital discharge for public out-of-hospital cardiac arrests (OHCAs) by patient sex between distinct regions. Objectives: We assessed if patient sex was associated with BCPR (primary outcome) and survival to hospital discharge (secondary outcome) for public OHCAs in North Carolina (NC) and Singapore (SG). We hypothesized that females in both regions would have lower receipt of BCPR and were less likely to survive to hospital discharge compared with men. Methods: We conducted a retrospective cohort study of the Cardiac Arrest Registry to Enhance Survival dataset (NC, 2013-2022) and Pan-Asian Resuscitation Outcomes Study (SG, 2010-2020). We excluded pediatric, traumatic, emergency medical services (EMS) witnessed cases, arrests in healthcare facilities and residential cases. Using logistic regression, we examined the association of sex with BCPR and survival to hospital discharge controlling for potential confounding variables such as age, race and the year of arrest. Results: There were 65,627 OHCAs in NC; upon exclusion 6,828 remained (78% males; mean age: 57±15, males, 54.7±18, females). In SG, there were 24,177 OHCAs; upon exclusion 3,617 cases remained (87% males; mean age: 57±14, males, 61±16.4, females). In NC, public BCPR rates were 48% for males and 44% for females. Females had a 13% adjusted lower odds of receiving less BCPR (adjusted OR 0.87 (CI 0.77, 0.99)). In SG, BCPR rates were 59% for males and 52% for females. Similarly, females had a 22% lower adjusted odds of receiving BCPR (adjusted OR 0.78 (CI 0.62, 0.98)). In NC, survival to hospital discharge rates for public OHCAs were 24% for males and 26% for females. Females had a 17% lower adjusted odds ratio of survival to hospital discharge compared to males (adjusted OR 1.17 (95% CI 1.01, 1.35)). In SG, public survival to hospital discharge rates were 12% for males and 9% for females. Females had a 36% adjusted lower odds of survival to hospital discharge compared to males (adjusted OR 0.64 (95% CI 0.43, 0.94)). Conclusion: In public OHCAs, females were less likely to receive BCPR than males in both regions. However, females were less likely to survive to hospital discharge in SG, whereas the opposite was seen in NC. Further research is needed to elucidate factors for these differences.