| Background:There is a lack of studies on screening regional temperature sensitive non-communicable diseases and assessing the mortality burden from sensitive diseases due to ambient temperatures,especially in ChinaObjective:To identify the regional extreme temperature-sensitive non-communicable diseases and vulnerable population through systematic screening analysis,and to assess the regional mortality burden of sensitive non-communicable diseases and vulnerable populations that were attributable to ambient extreme temperatures in China.Materials and methods:Daily meteorological data,daily air pollution data and daily mortality data in 19 cities or counties of China during 2014-2018 were collected,a two-stage model of the distributed lag nonlinear model(DLNM)was used to quantitatively analyze the relationship between extreme temperatures and mortality by different causes of death,gender,and age,and screen extreme temperature-sensitive diseases and vulnerable population.Multivariate meta-regression analysis was used to assess the relative risk of the 19 study areas at the overall,climatic and urban-rural levels to analyse the regional differences;by calculating attributable fractions(AFs),the mortality burden due to ambient temperature was assessedResults:This study analyzed the effects of extreme temperature on mortality by causes of disease,gender,and age groups in 19 regions of China.The main results were as follows:(1)The MMT of populationThe exposure-response relationship between ambient temperature and mortality showed "inverse-J" curve,and the minimum mortality temperature(MMT)of the population was 26.2℃,corresponding to the 66th percentile of the daily maximum temperature.The MMT of total in subtropical and temperate monsoon climate was 26.8℃,and 23.9℃,respectively.The MMT of circulatory system,respiratory system,nervous system,endocrine system diseases and injuries were 25.8℃,22.6℃,25.2℃,28.1℃ and 13.4℃,respectively.The MMT of different system diseases in subtropical zones was slightly higher than that in temperate zones(2)Regional extreme high temperature sensitive non-communicable diseaseIt was found that extreme high temperature could increase the relative risk of nervous system,injury,respiratory,circulatory,and endocrine diseases.The cumulative relative risk(CRR)and 95%confidence interval(CI)were 1.88(1.44,2.46),1.53(1.37,1.70),1.39(1.29,1.5 1),1.28(1.18,1.38)and 1.28(1.15,1.43).For total mortality,the CRR of people living in subtropical monsoon climates temperate monsoon climate zone were 1.24(1.15,1.34)and 1.29(1.22,1.37),respectively.For circulatory diseases,although the difference between climatic zones was not statistically significant(P=0.06),a greater relative risk was observed in subtropical,with C.RR(95%CI)of 1.32(1.16,1.50).For respiratory diseases,there was a greater relative risk in temperate monsoon climate zones(P=0.19),with CRR(95%CI)of 1.57(1.31,1.88).The effects of extreme high temperature on injuries,nervous system diseases and endocrine diseases were statistically significant only in the subtropics,with CRR(95%CI)were 1.52(1.32,1.76),1.93(1.30,2.87)and 1.38(1.14,1.66)The relative risks of the total and circulatory diseases were greater in rural areas,with CRR(95%CI)was 1.30(1.16,1.47)and 1.37(1.14,1.64)(3)Regional extreme low temperature sensitive non-communicable diseaseExtreme low temperature could increase the relative risk of circulatory and respiratory diseases,with CRR(95%CI)of 1.48(1.24,1.76)and 1.32(1.01,1.73),respectively.For total mortality,the statistical significance was observed only in the subtropical monsoon climate area,with CRR(95%CI)of 1.31(1.15,1.50).For circulatory diseases,although the difference between climatic zones was not statistically significant(P=0.39),it was found that the relative risk was greater in the temperate monsoon climate zone,with CRR(95%CI)of 1.64(1.03,2.60).The effects of extreme low temperature on respiratory system diseases,injuries,nervous system diseases and endocrine diseases were not statistically significant in both subtropical and temperate monsoon regions.It was found that the impacts of extreme low temperature on total and circulatory system diseases were greater in rural areas than in urban areas,with(RR(95%CI)of 1.46(1.10,1.93)and 1.97(1.28,3.03)(4)Vulnerable populationThe results of a stratified analysis by genders and age groups found that compared with men,women were at greater mortality risk,and CRR(95%CI)of extreme high temperature and extreme low temperature were 1.32(1.23,1.42)and 1.32(1.16,1.50).The susceptibility of the population to extreme temperatures increased with the increasing of age.The relative risk of mortality for different age groups ranged from 17%to 46%due to extreme high temperature and ranged from 19%to 87%for extreme low temperature(5)Attibutable mortality burdenThe mortality burden of extreme temperature sensitive non-communicable diseases attributable to ambient temperature was further assessed.For high temperatures,the mortality burden of injury was the largest,followed by nervous system diseases,respiratory system diseases,circulatory system system diseases and endocrine diseases.The attributable fractions(AFs)were 7.68%and 6.60%,3.16%,2.63%,and 2.02%,respectively.For low temperatures,the mortality burden of respiratory system diseases was the largest,followed by circulatory diseases,and the AF was 9.93%and 7.89%,respectively.In additional,the mortality burden by gender and age groups were evaluated and it was found that female had a greater mortality burden,with an AF value of 10.01%.Mortality burden increased with the age and the AF value changed from 2.17%to 15.22%for different age groups.The impact of extreme temperature on mortality by the climatic zone levels was explored.It was found that people who live in subtropical monsoon climates had a greater mortality burden,with the highest and lowest AF value of 2.91%and 6.58%,respectively.People living in rural areas had a greater mortality burden than those living in urban areas,with the highest and lowest AF value of 3.38%and 8.01%,respectively.Conclusion:Extreme temperatures could increase the mortality risk of various diseases,and cause a certain mortality burden.The MMTs of different diseases in subtropical zones were higher than those in temperate zones.The sensitive diseases of extreme high temperature include nervous system,injury,respiratory system,circulatory system and endocrine diseases.The sensitive diseases of extreme low temperature include circulatory system and respiratory system diseases.The effect of extreme high temperature on mortality showed a greater relative risk in the temperate monsoon climate zone,while the effect of extreme low temperature on mortality showed statistical significance only in the subtropical monsoon climate zone.The effect of extreme high and low temperatures on mortality showed a greater relative risk in rural areas.People live in subtropical monsoon climates had a higher mortality burden than those in temperate monsoon climates and people live in rural areas had a higher mortality burden than those in urban areas.In addition,it was indicated that the mortality burden attributable to non-optimal temperature increased with age.The female had a higher mortality burden,compared with male. |
PDF Full Text Request