TY - JOUR
T1 - Extreme temperature and out-of-hospital cardiac arrest in Japan
T2 - A nationwide, retrospective, observational study
AU - Onozuka, Daisuke
AU - Hagihara, Akihito
N1 - Funding Information:
This work was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI Grant numbers 15K08714 and 16H05247 . The funding source had no role in the study design, data collection, data analysis, data interpretation, or preparation of the manuscript.
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Background Although several studies have estimated the effect of extreme temperatures on out-of-hospital cardiac arrest (OHCA) in a single city or region, few have investigated variations in this association on a national level in Japan. Methods Daily data on OHCAs and weather variations were obtained from the 47 prefectures of Japan between 2005 and 2014. A time-series Poisson regression model with a distributed lag non-linear model was used to estimate the prefecture-specific effects. A multivariate meta-analysis was applied to pooled estimates on a national level. Results A total of 659,752 OHCA cases of presumed-cardiac origin met the inclusion criteria. The minimum morbidity percentile (MMP) was identified as the 84th percentile for temperature, ranging from 20.8 °C in Hokkaido to 28.8 °C in Okinawa. The overall pooled relative risk versus the MMP was 2.10 (95% CI: 1.84, 2.40) at extremely low temperatures (1st percentile) and 1.06 (95% CI: 1.01, 1.12) at extremely high temperatures (99th percentile). The effects of extremely high temperatures were acute and disappeared after a few days, while those of extremely low temperatures were also acute, but persisted for several days. The multivariate Cochran's Q test indicated no heterogeneity between prefectures (p = 0.699; I2 = 1.0%). Conclusions Extreme temperatures are associated with an increased risk of OHCA. Timely prevention strategies might reduce the risk of OHCA during extreme temperatures. Several days prevention should be also implemented for extremely low temperatures.
AB - Background Although several studies have estimated the effect of extreme temperatures on out-of-hospital cardiac arrest (OHCA) in a single city or region, few have investigated variations in this association on a national level in Japan. Methods Daily data on OHCAs and weather variations were obtained from the 47 prefectures of Japan between 2005 and 2014. A time-series Poisson regression model with a distributed lag non-linear model was used to estimate the prefecture-specific effects. A multivariate meta-analysis was applied to pooled estimates on a national level. Results A total of 659,752 OHCA cases of presumed-cardiac origin met the inclusion criteria. The minimum morbidity percentile (MMP) was identified as the 84th percentile for temperature, ranging from 20.8 °C in Hokkaido to 28.8 °C in Okinawa. The overall pooled relative risk versus the MMP was 2.10 (95% CI: 1.84, 2.40) at extremely low temperatures (1st percentile) and 1.06 (95% CI: 1.01, 1.12) at extremely high temperatures (99th percentile). The effects of extremely high temperatures were acute and disappeared after a few days, while those of extremely low temperatures were also acute, but persisted for several days. The multivariate Cochran's Q test indicated no heterogeneity between prefectures (p = 0.699; I2 = 1.0%). Conclusions Extreme temperatures are associated with an increased risk of OHCA. Timely prevention strategies might reduce the risk of OHCA during extreme temperatures. Several days prevention should be also implemented for extremely low temperatures.
UR - http://www.scopus.com/inward/record.url?scp=84991607116&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84991607116&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2016.10.045
DO - 10.1016/j.scitotenv.2016.10.045
M3 - Article
C2 - 27744154
AN - SCOPUS:84991607116
SN - 0048-9697
VL - 575
SP - 258
EP - 264
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -