兰州大气污染对循环系统疾病日住院人数影响

Impact of ambient air pollution on daily circulatory system disease hospitalization in Lanzhou city

目的探讨大气污染对居民循环系统疾病日住院人数的影响。方法收集2004年1月1日-2007年10月31日兰州城区每日空气污染指数（API）、气象资料,以及同时段的居民循环系统疾病住院数据;选用广义相加模型（GAM）的Poisson回归分析大气污染对居民循环系统健康的影响,并按性别、年龄和循环系统疾病类型进行分层分析。结果当日API上升一个四分位间距（48个单位）时,当日（滞后第0 d）至滞后第5 d循环系统疾病日住院人数增加比例为1.35%~3.62%,男性在API上升滞后第5 dRR值最高,为1.042 26（95%CI=1.025 10~1.058 81）,女性仅在滞后第4 dRR值高于男性;≥65岁者当日（滞后第0 d）至滞后第5 dRR值均〉1.02,16~64岁RR值只在滞后第2~5 d差异有统计学意义;滞后第5 d高血压和脑血管病住院人数RR值最高,分别为1.072 91（95%CI=1.044 48~1.102 11）和1.043 72（95%CI=1.014 32~1.073 97）,冠心病以第2 d最高,为1.025 21（95%CI=1.001 57~1.04941）。结论大气污染可增加居民循环系统疾病发病人数,对不同性别、年龄和循环系统疾病类型的影响存在差异。

Objective To explore the effect of ambient air pollution on hospital admissions of circulatory system diseases.Methods The data on air pollution index（API）,meteorology and the hospitalization of circulatory system diseases from Jan 1st 2004 through Oct 31st 2007 in Lanzhou city were collected.The effect of the ambient air pollution on the health of circulatory system was investigated using generalized additive Poisson models after controlling for the effect of long-term time trend,week and meteorology,and stratified by sex,age and the type of circulatory system diseaseses.Results The every one inter-quartile（48 units） increase in daily API was associated approximately with 1.35% to 3.62% increase of daily hospital admission for circulatory system disease for the delay range from current day to day 5 after the lag effect.The relative risk（RR） reached its highest（1.04226,95% confidence interval=1.02510-1.05881） among males five day after the lag effect.The RR for the females was higher than that of the males only in the four day after the lag effect.From current day to day 5 after the lag effect,the RR level was high than 1.02 for the subjects over 65-years-old.And the RR level by day 2 to day 5 after the lag effect for the subjects of 16 to 64 years old was of statistical significance.Ambient air pollution was more likely to affect hypertension patients and blood vessel of brain disease and the RR level reached its highest（1.07291,95%CI=1.04448-1.10211 and 1.04372,95%CI=1.01432-1.07397） at day 5 after the lag effect.The RR reached its highest（1.02521,95%CI=1.00157-1.04941） among coronary disease day 2 after the lag effect.Conclusion The results show that air pollution considerably affects the circulatory system morbidity among urban residents,and the effects are related to gender,age and the type of circulatory system diseases.