ABSTRACT
Objective @#To evaluate the excess mortality risk related to heat wave in Ningbo, Zhejiang from 2013 to 2018, so as to provide a basis for formulating coping strategies for heat wave.@*Methods @#The data of daily mortality, meteorological and air quality from May to October in Ningbo from 2013 to 2018 were obtained from Ningbo Center for Disease Control and Prevention, Ningbo Meteorological Bureau and Environmental Monitoring Center of Ningbo, respectively. The generalized linear model ( GLM ) and distributed lag non-linear model ( DLNM ) were used to estimate the associations between heat wave and cause-specific mortality. @*Results @#Among 1 104 days of the study period, 18 heat waves occured and lasted for 132 days, accounting for 11.96%. A total of 102 954 deaths were reported in the same period. The risks of mortality in circulatory system diseases ( RR=1.09, 95%CI: 1.03-1.16 ), respiratory system diseases ( RR=1.14, 95%CI: 1.04-1.25 ), digestive system diseases ( RR=1.38, 95%CI: 1.15-1.65 ), nervous system diseases ( RR=1.32, 95%CI: 1.08-1.61 ), mental disorders ( RR=1.51, 95%CI: 1.12-2.03 ) and accidental injury ( RR=1.18, 95%CI: 1.06-1.32 ) and all causes ( RR=1.10, 95%CI: 1.06-1.14 ) increased at lag 0-1 day of heat wave. The total excess death related to heat wave was 1 218 ( 95%CI: 731-1 705 ) . The excess deaths of circulatory system diseases, respiratory system diseases, accidental injury, digestive system diseases, nervous system diseases, mental disorders, urinary system diseases and endocrine system diseases were 313 ( 95%CI: 104-556 ), 206 ( 95%CI: 59-368 ), 164 ( 95%CI: 55-292 ), 122 ( 95%CI: 48-208 ), 69 ( 95%CI: 17-131 ), 56 ( 95%CI: 13-113 ), 18 ( 95%CI: -15-64 ) and 3 ( 95%CI: -51-72 ). The excess deaths of urinary system and endocrine system diseases was not statistically significant ( P>0.05 ). @*Conclusion @#Heat wave can increase the mortality risk on the day and after a day in Ningbo from 2013 to 2018. Circulatory system diseases, respiratory system diseases and accidental injury rank top three in excess deaths.