Abstract 9086: Sex Differences in the Association Between Bystander CPR and Survival for Patients With Out-of-Hospital Cardiac Arrest

Abstract

Background: Bystander cardiopulmonary resuscitation (CPR) is associated with a better survival outcome in patients with out-of-hospital cardiac arrest (OHCA). However, there may be cultural barriers in performing high-quality bystander CPR in women in some non-Western countries and the effect of bystander CPR on survival outcomes may differ by patients’ sex. Methods: Using data between 2012-2018 from a national OHCA registry from the Republic of Korea, we identified adult patients with OHCA of presumed cardiac etiology. The main exposures were bystander CPR and patients’ sex. The primary outcome was survival discharge and the secondary outcome was favorable neurological survival. Multivariable logistic regression evaluated the association between bystander CPR and survival, adjusted for patients’ age, sex, socio-economic status, year of arrest, witnessed arrest status, initial OHCA rhythm, location of arrest, urbanization level of arrest location, and type of bystander. The interaction between bystander CPR and sex was explicitly evaluated in the models. Results: Of 101,505 patients with OHCA in the cohort, 34,124 (33.6 %) were women and 67,381 (64.4 %) were men. Bystander CPR was performed on 18,481 (54.2%) women and 35,904 (53.3%) men (p=0.07). Unadjusted rates of survival discharge were 4.5% in women and 9.5 % in men (p<0.001), and rates of favorable neurological survival were 2.5% in women and 6.4% in men (p<0.001). In multivariable logistic regression models, there was a significant interaction (p=0.005) between bystander CPR and sex for survival to discharge, with an adjusted OR for bystander CPR of 1.16 (95% CI: 1.08-1.23) in men and 0.91 (95% CI: 0.80-1.02) in women. For favorable neurological survival, there was also a significant interaction (p=0.01) between sex and bystander CPR, with an adjusted OR for bystander CPR of 1.47 (95% CI: 1.36-1.60) in men and 1.16 (95% CI: 0.98- 1.37) in women. Conclusions: In a national registry of OHCA from the Republic of Korea, men who received bystander CPR were more likely to survive whereas women who received bystander CPR were not.