Introduction:
Approximately 1,000 out-of-hospital cardiac arrest (OHCA) occur per day in the United States. Although survival rates remains low, the extent to which OHCA neurological outcomes differ between men and women remains poorly characterized.
Methods:
Within the national Cardiac Arrest Registry to Enhance Survival (CARES) registry, we identified 195,722 adult individuals with an OHCA between 2013-2017. Using multi-variable logistic regression models, we evaluated for sex differences in rates of survival to hospital discharge and favorable neurological outcome (survival with discharge CPC score of 1 or 2), adjusted for cardiac arrest characteristics, race, location, year of arrest, age, and use of targeted temperature management (TTM) and coronary angiography.
Results:
Overall, 70,767 (31%) patients were women. Median age was 64 and 62 years for women and men, respectively. An initial shockable rhythm (14.9% vs. 25.7%) and a witnessed arrest (40.9% vs. 45.6%) was more common in men. Bystander CPR was provided to 37% of women and 39% of men. Men were less likely to survive to hospital discharge than women (8.7% vs. 10.9%; adjusted OR 0.75, 95% CI 0.73, 0.78). Similarly, men were less likely to have favorable neurological outcome (6.6% vs. 9.2% for women; adjusted OR 0.78, 95% CI 0.74, 0.82). Further interaction analysis for the pre-hospital elements found small, but statistically significant sex differences in favorable neurological survival for witnessed status (among female OR 2.29, 95% CI 2.10, 2.49; among males OR 2.07, 95% CI 1.92, 2.23, p= 0.04) and for bystander CPR (among females OR 1.20, 95% CI 1.11, 1.29; among males OR 1.34, 95% CI 1.27, 1.42, p= 0.01). Interaction of sex with the hospital level variables of TTM and coronary angiography, for the subset of patients that survived to hospital admission, had no sex differences in favorable neurological outcome.
Conclusion:
Our analysis shows that for OHCA in the United States, women have better survival outcomes than men. There was a sex differences in the pre-hospital variable of BCPR, but not in the other modifiable variables of TTM and coronary angiography. Further study is needed to better understand sex differences in overall survival and neurological outcomes.
Mortality in young adults following out-of-hospital cardiac arrest: Evidence from two nationwide propensity-matched cohorts in the United States a decade apart
