兰州市呼吸系统疾病空气质量健康指数构建

Construction of respiratory disease-related air quality health index in Lanzhou

目的通过研究空气污染物对不同性别、年龄人群健康效应,构建兰州市不同性别、年龄人群空气质量健康指数(air quality health index,AQHI),并对空气质量进行分级。方法采用时间序列广义相加模型(generalized additive models,GAM)研究2001—2009年兰州市空气污染物与呼吸系统疾病日入院人数的健康效应,进而构建兰州市空气质量健康指数(lanzhou air quality health index,LAQHI),并比较AQHI、空气质量指数(AQI)和空气污染指数(API)预测健康的能力。结果 SO2、NO2和PM10对不同性别、年龄人群呼吸系统疾病入院均具有一定的相关和滞后效应,除≥65岁老年人群,SO2在当天、NO2滞后1d、PM10滞后3~6 d即可引起呼吸系统疾病日入院人数增加;SO2对年龄≤15岁人群在滞后1 d,NO2对女性人群在当天,PM10对年龄≤15岁人群在滞后4 d的相对危险度(RR)最高,RR分别为1.082(95%CI:1.055~1.110)、1.065(95%CI:1.037~1.094)和1.036(95%CI:1.024~1.049)。AQHI处于低、中、高、重度等级的天数占总天数的比例分别为51.6%~90.0%、9.3%~31.6%、0.7%~12.1%和0.0%~4.6%,而年龄≥65岁老年人群及男性处于中、高、重度比例均较高,分别为32%、12%、4%及24%、6%和1%,且AQHI预测人群健康的能力要强于AQI和API。结论兰州市空气污染物对不同性别、年龄人群呼吸系统疾病入院均有一定影响,且具有一定滞后效应,其中对女性及年龄≤15岁人群的影响较为显著;AQHI能够用于兰州市空气质量分级,且对健康预测能力较AQI和API理想。

Objective To construct the air quality health index（AQHI） for population with different ages and genders and to classify the air quality in Lanzhou, based on the assessment of the health effect of air pollution. Methods Semi-parametric generalized additive model（GAM） was used for the time series analysis, to estimate the health effect of air pollution on daily hospital admissions for respiratory diseases in 2001-2009, Lanzhou air quality health index（LAQHI） was constructed and the abilities to predict health was compared among AQHI, AQI and API. Results Air pollutants（SO2, NO2 and PM10） presented correlations and lag effects on respiratory diseases in population with different ages and genders. Except for population aged over 65, SO2（lag0）, NO2（lag1）, and PM10（lag3-6） could increase the hospital admissions for respiratory diseases.The highest relative risk of daily hospital admissions for respiratory diseases was found among population aged 15 and younger [ RR： 1.082（95%CI： 1.055-1.110）] associated with an IQR concentration increase in SO2（lag0）, among female [RR： 1.065（95%CI： 1.037-1.094）] in NO2（lag1）, among population aged 15 and younger [RR： 1.036（95% CI： 1.024-1.049）] in PM10（lag4） respectively.The days with AQHI classified as low, medium, high and severe risk level accounted for 51.6%-90.0%,9.3%-31.6%,0.7%-12.1% and 0.0%-4.6% of the whole days among whole population respectively,and those classified as medium, high and severe risk level accounted for 32%, 12%, 4% of the whole days among population aged ≥65, and 24%, 6%, 1% for male respectively. Ultimately, AQHI was more comprehensive than AQI and API in prediction for health effect of air pollution.Conclusion Air pollutants（SO2, NO2 and PM10） have lag effects on respiratory diseases in different population, the effects for female and population aged≤15 are prominent in Lanzhou; AQHI can be applied as a reference index in classification for air quality in Lanzhou,is more comprehensive in prediction for health than AQI and API.