Neurological prognostication by gender in out-of-hospital cardiac arrest patients receiving hypothermia treatment.

OBJECTIVES

This study examined whether the extent to which out-of-hospital cardiac arrest (OHCA) patients recover neurological function after therapeutic hypothermia (TH) is augmented in specific gender, age, and primary ECG group.

METHODS

A cross-sectional analysis was conducted using a nationwide database of OHCAs in Korea which was constructed from emergency medical services (EMS) run sheet and hospital medical record review between 2008 and 2012. Patients survived to admission were enrolled. Study endpoint was survival with neurological recovery (cerebral performance category 1 and 2). Main exposure was hypothermia. Gender, age group (<45, 45-65, and >65 years old) and primary ECG rhythm were considered as potential effect modifiers. Potential factors were accounted for adjustment using multivariable logistic regression.

RESULTS

Survival with good neurological recovery was 14.6% (9.3% in men and 17.2% in women). TH was performed in 15.5% (n=1140). Strata-specific crude analysis showed enhanced neurological recovery for women of childbearing ages compared to men counterparts (OR=4.38 (1.39, 13.74) vs. OR=1.73 (0.97, 3.10)). After adjusted for effect modifiers and covariates, the strongest effect of TH on neurological recovery was observed in men younger than 45 years of age with shockable rhythm (OR=2.00 (1.26, 3.19)), whereby no statistically significant associations were found in all women. In both genders, the magnitude of association decreased with age and having non-shockable cardiac rhythm.

CONCLUSION

TH was the strongest indicator for good neurological recovery in <45-year old men with shockable cardiac rhythm. Across all age groups, women were less likely to benefit from TH than men.