title: The effects of sex on out-of-hospital cardiac arrest outcomes.
abstract: OBJECTIVE
  We examined the effects of sex on out-of-hospital cardiac arrest outcomes. There is evidence that women are more likely to survive cardiac arrest than men. However, few large studies have examined these sex differences in detail. It is unknown whether the female survival advantage is age-specific or whether sex affects neurologic outcomes after cardiac arrest events.
  
  
  METHODS
  Data were analyzed from a nationwide population-based out-of-hospital cardiac arrest database (between January 2005 and December 2007) involving 318,123 patients (male: 188,357, female: 129,766) to assess the effects of sex on out-of-hospital cardiac arrest outcomes in Japan. We selected 276,590 patients aged 20 to 89 years with out-of-hospital cardiac arrest and compared the frequencies of initial cardiac rhythms, 1-month survival rates, and favorable neurologic outcome rates between sexes.
  
  
  RESULTS
  The incidence of out-of-hospital cardiac arrest was higher in men than in women (men: 0.12%; women: 0.07%). Men were witnessed more often while out-of-hospital cardiac arrest was occurring (men: 42.1% and women: 36.9%), typically presented with initial ventricular fibrillation/ventricular tachycardia rhythms, and had a higher 1-month survival rate overall after out-of-hospital cardiac arrest events (men: 5.2% and women: 4.3%). However, the rate of survival with a favorable neurologic outcome for women aged 30 to 49 years was significantly higher than that for men within the same age range. Among patients initially presenting with ventricular fibrillation/ventricular tachycardia, the rate of survival with favorable neurologic outcome was higher for women than men in the group aged 40 to 59 years.
  
  
  CONCLUSIONS
  Our results suggest that men have a higher 1-month survival rate after out-of-hospital cardiac arrest because of a higher frequency of ventricular fibrillation/ventricular tachycardia presentation compared with women. Although patients of both sexes with out-of-hospital cardiac arrest initially presenting with ventricular fibrillation/ventricular tachycardia exhibited similar overall survival rates, the rate of survival with favorable neurologic outcome was significantly higher for women than men in the group aged 40 to 59 years.
authors: Department of Public Health, Nara Medical University School of Medicine, Japan. makahane@naramed-u.ac.jp
authors: Manabu
authors: M
authors: Akahane
authors: Toshio
authors: T
authors: Ogawa
authors: Soichi
authors: S
authors: Koike
authors: Seizan
authors: S
authors: Tanabe
authors: Hiromasa
authors: H
authors: Horiguchi
authors: Tatsuhiro
authors: T
authors: Mizoguchi
authors: Hideo
authors: H
authors: Yasunaga
authors: Tomoaki
authors: T
authors: Imamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation; D004632:Emergency Medical Services; D005260:Female; D006323:Heart Arrest / Q000401:mortality*; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012307:Risk Factors; D012727:Sex Characteristics; D015996:Survival Rate; D055815:Young Adult