山东省低温暴露所致死亡风险的季节内差异分析

Intraseasonal variation of the association between cold temperature and mortality risk in Shandong Province

目的分析山东省低温暴露死亡风险的季节内差异。方法通过山东省疾病预防控制中心收集2013—2018年山东省的全人群死亡数据, 基本资料主要包括死亡日期、年龄、性别、受教育程度、死亡原因、家庭住址等;通过中国气象数据网同期逐日气象资料, 主要包括日平均温度(℃)、日平均相对湿度(%)等0.01°×0.01°经纬度的网格坐标数据。将冷季定义为11月至次年2月, 其中前两个月为早期冷季, 后两个月为晚期冷季, 极端低温定义为冷季温度范围中的P10。利用时间分层的病例交叉设计结合分布滞后非线性模型, 分析冷季的温度与死亡的关联以及不同滞后时间下极端低温与死亡的关联, 并比较冷季早期(11—12月)与晚期(1月至次年2月)的季节内差异。结果 2013—2018年山东省冷季四个月温度变化范围为(-17.3~18.6)℃, P10(即极端低温)为-13.7 ℃。冷季早期日均温度为(3.63±4.66)℃, 晚期日均温度为(-0.09±3.70)℃;冷季早期日均相对湿度为(63.89±14.75)%, 晚期日均相对湿度为(62.27±14.19)%。山东省2013—2018年冷季死亡1 473 300例, 其中男性824 601例(55.97%);年龄<65岁者349 824例(23.75%);死于循环系统疾病803 691例(54.55%), 死于呼吸系统疾病140 415例(9.53%)。分布滞后非线性模型模型分析结果显示, 以冷季最适温度18.6 ℃为参考, 冷季4个月极端低温的累积OR为1.74(95%CI:1.63, 1.86);冷季早期和晚期累积OR分别为1.50(95%CI:1.32, 1.71)、2.56(95%CI:2.12, 3.09)(P<0.001);滞后效应持续12 d。结论山东省冷季的低温暴露所致死亡风险存在季节内差异, 冷季晚期高于早期。

Objective To explore the intraseasonal variation in mortality risk from cold temperature exposure in Shandong Province.Methods Mortality data in Shandong province from 2013 to 2018 were collected from the cause of death surveillance system of Shandong Center for Disease Control and Prevention.The basic information mainly included the date of death,age,gender,education level,cause of death,home address,etc.The daily meteorological data from China Meteorological Data Network mainly included the grid coordinate data of 0.01°×0.01°latitude and longitude,such as daily average temperature(℃)and daily average relative humidity(%).The cold season was from November to February.The first two months were the early cold season and the last two months were the late cold season.The extreme cold temperature was defined as the 10th percentile of the temperature range of cold season.Time-stratified case crossover design with distributed lag non-linear model analyzed the association between temperature and mortality and the association between extreme low temperature and mortality in different lag days in the cold season,and compared the intraseasonal differences between early(November-December)and late(January-February)cold season.Results The temperature ranged from-17.3℃to 18.6℃in Shandong Province during the cold season from 2013 to 2018,and the P10(extreme low temperature)was-13.7℃.The average daily temperature in the early cold season was(3.63±4.66)℃.The temperature in the late cold season was(-0.09±3.70)℃.The average daily relative humidity was(63.89±14.75)%in the early cold season and(62.27±14.19)%in the late cold season.This study included 1473300 deaths in the cold season in Shandong Province between 2013 and 2018.There were 824601(55.97%)males and 349824(23.75%)cases aged<65 years.There were 803691(54.55%)deaths due to circulatory diseases and 140415(9.53%)deaths due to respiratory diseases.The results of DLNM showed that the cumulative OR of extreme low temperature in the four months of cold season was 1.74(95%CI:1.63,1.86)with the optimal temperature of 18.6℃as the reference.The cumulative OR values of early and late cold season were 1.50(95%CI:1.32,1.71)and 2.56(95%CI:2.12,3.09),respectively(P<0.001).The lag effect lasted for 12 d.Conclusion There is an intraseasonal variation of the association between cold temperature and mortality risk in Shandong Province.The mortality risk related to cold temperature in the late cold season is higher than that in the early cold season.