气温与PM2.5协同作用对疾病急诊就诊人数的影响

摘要

为评价气温和PM2.5协同作用对不同种类疾病急诊就诊人数的影响,采用广义相加模型(GAMs)中的不分层模型、非参数二元响应模型和温度分层模型,在控制了时间序列长期趋势、"星期几效应"、节假日效应和相对湿度等因素的影响后,分析2009～2011年北京市PM2.5在不同气温条件下对相关疾病急诊就诊人数影响的暴露-反应关系.结果表明,随着选取的气温分层临界值升高,PM2.5在高温条件下的效应逐渐增强,当临界值为28℃时,高温条件下的效应最显著,此时PM2.5浓度每升高10μg/m3,全急诊人数、呼吸系统和循环系统疾病急诊就诊人数的超额增加百分比分别为0.15％(95％CI:0.11％,0.19％),0.35％(95％CI:0.26％,0.44％)和0.34％(95％CI:0.09％,0.59％),而<28℃的条件下无统计学意义,表明高温与PM2.5对人群健康的影响存在协同加强效应.%To quantitatively evaluate the synergetic effect of ambient temperature (AT) and PM2.5 on different diseases' emergency room visits (ERVs) in Beijing. After considering some potential confounding factors, such as long term trend of time series, "day of week" effect, holiday effect, and relative humidity, the generalized additive models (GAMs) including non-stratification model, nonparametric bivariate response model and temperature-stratified parametric model, were used to analyze the exposure-effect relationship between PM2.5 and ERVs in different temperature conditions from 2009 to 2011 in Beijing. The results showed that, the health effect of PM2.5 significantly enhanced under higher temperature with the temperature stratification critical value increasing. The exposure-response relationship between PM2.5 and ERVs appeared most significant when 28℃ was chosen as a critical value. The effect estimates per 10μg/m3 increase in PM2.5 corresponding to 0.15％ (95％ confidence interval (CI): 0.11％, 0.19％), 0.35％(95％CI: 0.26％, 0.44％) and 0.34％(95％CI: 0.09％, 0.59％) increase of total, respiratory and cardiovascular ERVs on high temperature (>28℃), respectively. However, there was no statistical significance when the temperature was less than 28℃. It means that there was a synergistic strengthening effect of high temperature and PM 2.5 on public health in Beijing.