Background: Although some studies have shown that women in their reproductive years have better resuscitation outcomes of out-of-hospital cardiac arrest (OHCA), conflicting results and methodological problems have also been noted. Thus, we evaluated the resuscitation outcomes of OHCA of females by age.
Methods: This was a prospective observational study using registry data from all OHCA cases between 2005 and 2012 in Japan. The subjects were females aged 18-110 years who suffered an out-of-hospital cardiac arrest. Logistic regression analyses were performed using total and propensity-matched patients.
Results: There were 381,123 OHCA cases that met the inclusion criteria. Among propensity-matched patients, females aged 18-49 and 50-60 years of age had similar rates of return of spontaneous circulation before hospital arrival and 1-month survival (all p>0.60). In contrast, females aged 18-49 years of age had significantly lower rates of 1-month survival with minimal neurological impairment than did females aged 50-60 years of age (after adjusting for selected variables: Cerebral Performance Category scale 1 or 2 (CPC (1, 2)), OR=0.45, p=0.020; Overall Performance Category scale 1 or 2 (OPC (1, 2)): OR=0.42, p= 0.014; after adjustment for all variables: CPC (1, 2), OR=0.27, p= 0.008; OPC (1, 2), OR=0.29, p=0.009).
Conclusion: Women of reproductive age did not show improved resuscitation outcomes in OHCA. Additionally, women in their reproductive years showed worse neurological outcomes one month after the event, which may be explained by the negative effects of estrogen. These findings need to be verified in further studies.
Keywords: Out-of-hospital cardiac arrest; cardiopulmonary resuscitation; epidemiology; gender; sudden death; women.