重庆市日平均气温与居民因心脑血管疾病死亡的时间序列分析

The Cardiovascular and Cerebrovascular Death among Chongqing Residents and Chongqing Daily Mean Temperature:A Time Series Analysis

目的分析重庆市日平均气温与居民心脑血管疾病死亡的时间序列。方法收集重庆市2019年1月至2019年12月心脑血管疾病死亡病例,按照心脑血管疾病的病种与类型,进行分层抽样,随机选取25065例作为研究对象,应用广义相加模型和时间序列分析方法,分析日平均气温、年龄、性别与心脑血管疾病死亡之间的关联。结果心脑血管疾病死亡较多发于1月、12月、11月,占比总病例数40.44%,较少发于8月、7月、6月,占比11.81%。冬季心脑血管疾病患者因温度变化发病死亡的风险较高。不同年龄段患者中,年龄≥65岁患者因温度变化发病死亡的风险较高。女性患者因温度变化发病死亡的风险较男性患者高。全年模型拟合结果显示,时间趋势的自由度为6/年时,全年日平均气温与心脑血管疾病死亡人数有关,全年日平均气温在滞后1 d、5 d时有统计学意义(P<0.05),日均气温降低1℃时,心脑血管疾病死亡人数增加0.07%和0.15%。春季时间趋势的自由度为6/年时,春季日平均气温与心脑血管疾病死亡人数有关,春季日平均气温在滞后2 d、5 d时有统计学意义(P<0.05),日均气温降低1℃时,心脑血管疾病死亡人数增加0.04%和0.11%。夏季时间趋势的自由度为6/年时,夏季日平均气温与心脑血管疾病死亡人数有关,夏季日平均气温在滞后1、5d时有统计学意义(P<0.05),日均气温升高1℃时,心脑血管疾病死亡人数增加0.01%和0.08%。秋季时间趋势的自由度为6/年时,秋季日平均气温与心脑血管疾病死亡人数有关,秋季日平均气温在滞后1、5 d时有统计学意义(P<0.05),日均气温降低1℃时,心脑血管疾病死亡人数增加0.06%和0.17%。冬季时间趋势的自由度为6/年时,冬季日平均气温与心脑血管疾病死亡人数有关,冬季日平均气温在滞后1、5 d时有统计学意义(P<0.05),日均气温降低1℃时,心脑血管疾病死亡人数增加0.19%和0.59%。结论日平均气温与居民心脑血管疾病死亡有着密切的关系,且存在滞后效应。应建立日平均气温与心脑血管疾病死亡率之间的分布滞后非线性模型。心脑血管疾病患者应于冬季提高风险意识。65岁以上女性患者应注意防控相关疾病。

Objective To analyze the time series of Chongqing daily mean temperature and the death of cardiovascu⁃lar diseases(CVD)and cerebrovascular diseases(CeVD)in Chongqing residence.Methods The data of CVD and CeVD death in Chongqing during the period from January,2019 to December,2019 were collected;based on the type of diseas⁃es,stratified sampling was performed and 25065 cases were randomly selected;generalized additive model and time se⁃ries analysis were applied in analyzing the relationship of CVD and CeVD with daily mean temperature,age and sex and cardiovascular and cerebrovascular diseases.Results The occurrence of CVD and CeVD death was relatively more fre⁃quent in January,December and November,accounting for 40.44%of annual CVD and CeVD death,and was relatively less frequent in August,July and June,accounting for 11.81%;among the 4 seasons,the risk of CVD and CeVD death were higher in winter due to temperature changes;among different age group,cases over 65 were of higher risk of CVD and CeVD death due to temperature changes;women were of higher risk of CVD and CeVD death due to temperature changes;according to annual model fitting results,when the degree of freedom of time trend was 6/year,annual daily mean temperature was related to CVD and CeVD death and the relation was statistically significant with 1 day’s lag and 5 days’lag(P<0.05)as the death of CVD and CeVD increased by 0.07%and 0.15%when daily average temperature de⁃creased by 1℃;when the degree of freedom of the time trend in spring was 6/year,daily mean temperature was related to CVD and CeVD death and the relation was statistically significant with 2 days’lag and 5 days’lag(P<0.05)as the death of CVD and CeVD increased by 0.04%and 0.11%when daily average temperature decreased by 1℃;when the degree of freedom of the time trend in summer was 6/year,daily mean temperature was related to CVD and CeVD death and the relation was statistically significant with 1 day’s lag and 5 days’lag(P<0.05)as the death of CVD and CeVD in⁃creased by 0.01%and 0.08%when daily average temperature increased by 1℃;when the degree of freedom of the time trend in autumn was 6/year,daily mean temperature was related to CVD and CeVD death and the relation was statistical⁃ly significant with 1 day’s lag and 5 days’lag(P<0.05)as the death of CVD and CeVD increased by 0.06%and 0.17%when daily average temperature decreased by 1℃;when the degree of freedom of the time trend in winter was 6/year,daily mean temperature was related to CVD and CeVD death and the relation was statistically significant with 1 day’s lag and 5 days’lag(P<0.05)as the death of CVD and CeVD increased by 0.19%and 0.59%when daily average temper⁃ature decreased by 1℃.Conclusions Daily mean temperature is closely related to the death of CVD and CeVD with a lag effect;a distributed lag non-linear model of daily mean temperature and the occurrence of CVD and CeVD death should be built;cases with CVD and CeVD should raise their risk awareness in winter and relevant protection work,re⁃duce the attack caused by temperature changes;female cases with age over 65 years old should pay attention to the pre⁃vention and control of related diseases.