Sex Differences in Survival From Out-of-Hospital Cardiac Arrest in the Era of Regionalized Systems and Advanced Post-Resuscitation Care

Background-The purpose of this study was to evaluate sex differences in out-of-hospital cardiac arrest (OHCA) characteristics, interventions, and outcomes. Methods and Results-This is a retrospective analysis from a regionalized cardiac arrest system. Data on patients treated for OHCA are reported to a single registry, from which all adult patients were identified from 2011 through 2014. Characteristics, treatment, and outcomes were evaluated with stratification by sex. The adjusted odds ratio (OR) for survival with good neurological outcome (cerebral performance category 1 or 2) was calculated for women compared to men. There were 5174 out-of-hospital cardiac arrests (OHCAs; 3080 males and 2094 females). Women were older, median 71 (interquartile range [IQR], 59-82) versus 66 years (IQR, 55-78). Despite similar frequency of witnessed arrest, women were less likely to present with a shockable rhythm (22% vs 35%; risk difference [RD], 13%; 95% CI, 11-15), have ST-segment elevation myocardial infarction (23% vs 32%; RD, 13%; 95% CI, 7-11), or receive coronary angiography (11% vs 25%; RD, 14%; 95% CI, 12-16), percutaneous coronary intervention (5% vs 14%; RD, 9%; 95% CI, 7-11), or targeted temperature management (33% vs 40%; RD, 7%; 95% CI, 4-10). Women had decreased survival to discharge (33% vs 40%; RD, 7%; 95% CI, 4-10) and a lower proportion of good neurological outcome (16% vs 24%; RD, 8%; 95% CI, 6-10). In multivariable modeling, female sex was not associated with decreased survival with good neurological outcome (OR, 0.9; 95% CI, 0.8-1.1). Conclusions-Sex-related differences in OHCA characteristics and treatment are predictors of survival outcome disparities. With adjustment for these factors, sex was not associated with survival or neurological outcome after OHCA.