The effect of sex and age on return of spontaneous circulation and survival to hospital discharge in patients with out of hospital cardiac arrest: A retrospective analysis of a Canadian population.

OBJECTIVES

We evaluated the effect of sex and age on out-of-hospital cardiac arrest (OHCA) outcomes in a Canadian population.

METHODS

This study was a retrospective analysis of the British Columbia (BC) Cardiac Arrest Registry (2011-16). We included adult, non-traumatic, EMS-treated OHCA. We stratified the cohort into four groups by age and sex: younger females (18-47 years of age), younger males (18-47 years of age), older females, and older males (>53 years old). We used logistic regression to examine the effect of sex and interaction effect of sex and age on ROSC and survival to hospital discharge.

RESULTS

We included 8115 patients; 31.4% were females. Females had a lower proportion of OHCA in public locations, bystander witnessed arrests, and with initial shockable rhythms. Overall, females had greater adjusted odds of ROSC (OR 1.29, 95% CI 1.15-1.42, p < 0.001). The ROSC advantage was significant in females with non-shockable rhythms (OR 1.48, 95% CI 1.24-1.78, p < 0.001) and females of premenopausal age. However, there was no significant difference in survival to hospital discharge between females and males overall or by sex-age groups. Both younger females and younger males have higher odds of survival to hospital discharge compared to older females and males. Older females had the lowest survival rate among all other sex-age groups.

CONCLUSIONS

Female sex was associated with ROSC but not survival to hospital discharge. In the post-arrest phase, females, specifically those in the older age group, had a higher death rate, demonstrating the need for sex- and age-specific research in pre-and-post-OHCA care.