Reduction in incidence and fatality of out-of-hospital cardiac arrest in females of the reproductive age.
OBJECTIVE
The aim of this study was to determine relative risk (RR) of incidence and fatality of out-of-hospital cardiac arrest (OHCA) by gender and oestrogen status.


RESULTS
In a prospective, population-based observational study from 1998 through 2007, incidence and neurologically intact 1-month survival after OHCA were compared by gender after grouping: 0-12 years, 13-49 years, and > or =50 years according to menarche and menopause age. Among 26 940 cardiac arrests, there were 11 179 females and 15 701 males. Age-adjusted RR of females for OHCA incidence compared with males was 0.72 [95% confidence interval (CI), 0.58-0.91] in age 0-12 years, 0.39 (95% CI, 0.37-0.43) in age 13-49 years, and 0.54 (95% CI, 0.52-0.55) in age > or =50 years. Females aged 13-49 years had a significantly higher good neurological outcome than males [adjusted odds ratio (OR), 2.00 (95% CI 1.21-3.32)]. This sex difference was larger than that in the other age groups [adjusted OR, 0.82 (95% CI, 0.06-12.02) in age 0-12 years and 1.23 (95% CI, 0.98-1.54) in age > or =50 years].


CONCLUSIONS
Reproductive females had a lower incidence and a better outcome of OHCA than females of other ages and males, which might be explained by cardioprotective effects of endogenous oestrogen on OHCA.
Kyoto University Health Service, Yoshida Honmachi, Sakyo-Ku, Kyoto 606-8501, Japan.
Tetsuhisa
T
Kitamura
Taku
T
Iwami
Graham
G
Nichol
Tatsuya
T
Nishiuchi
Yasuyuki
Y
Hayashi
Chika
C
Nishiyama
Tomohiko
T
Sakai
Kentaro
K
Kajino
Atsushi
A
Hiraide
Hisashi
H
Ikeuchi
Hiroshi
H
Nonogi
Takashi
T
Kawamura
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D004967:Estrogens / Q000378:metabolism; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000097:blood / Q000401:mortality / Q000517:prevention & control*; D011379:Prognosis; D011446:Prospective Studies; D017678:Sex Distribution; D013997:Time Factors
D004967:Estrogens