Institute of Cancer Epidemiology, Danish Cancer Society, Strandboulevarden 49, Copenhagen 2100, Denmark.
Thorax. 2012 Jan;67(1):6-11. doi: 10.1136/thoraxjnl-2011-200711. Epub 2011 Sep 2.
Exposure to air pollution in early life contributes to the burden of childhood asthma, but it is not clear whether long-term exposure to air pollution can lead to asthma onset or progression in adulthood.
The authors studied the effect of exposure to traffic-related air pollution over 35 years on the risk for asthma hospitalisation in older people.
57 053 participants in the Danish Diet, Cancer and Health cohort, aged 50-65 years at baseline (1993-1997), were followed up for first hospital admission for asthma until 2006, and the annual nitrogen dioxide (NO(2)) levels were estimated as a proxy of the exposure to traffic-related air pollution at the residential addresses of the participants since 1971. The association between NO(2) and hospitalisation for asthma was modelled using Cox regression, for the full cohort and in people with and without previous hospitalisations for asthma, and the effect modification by comorbid conditions was assessed.
During 10.2 years' median follow-up, 977 (1.9%) of 53 695 eligible people were admitted to hospital for asthma: 821 were first-ever admissions and 176 were readmissions. NO(2) levels were associated with risk for asthma hospitalisation in the full cohort (HR and 95% CI per IQR, 5.8 μg/m(3): 1.12; 1.04-1.22), and for first-ever admissions (1.10; 1.01-1.20), with the highest risk in people with a history of asthma (1.41; 1.15-2.07) or chronic obstructive pulmonary disease (COPD) (1.30; 1.07-1.52) hospitalisation.
Long-term exposure to traffic-related air pollution increases the risk for asthma hospitalisation in older people. People with previous asthma or COPD hospitalisations are most susceptible.
生命早期接触空气污染会增加儿童哮喘的负担，但目前尚不清楚长期暴露于空气污染是否会导致成年人哮喘发病或加重。
本研究旨在探讨 35 年来交通相关空气污染暴露对老年人哮喘住院风险的影响。
在丹麦饮食、癌症和健康队列中，共有 57053 名年龄在 50-65 岁的参与者于基线（1993-1997 年）入组，随访至 2006 年首次因哮喘住院，通过参与者的住址估计每年二氧化氮（NO2）水平作为交通相关空气污染暴露的替代指标。采用 Cox 回归模型分析 NO2 与哮喘住院的相关性，在整个队列中以及在既往无哮喘住院史和有哮喘住院史的人群中进行分析，并评估合并症的效应修饰作用。
在中位随访 10.2 年期间，53695 名符合条件的人中共有 977 人（1.9%）因哮喘住院：821 人为首次住院，176 人为再次住院。NO2 水平与整个队列的哮喘住院风险相关（每 IQR 增加 5.8μg/m3 的 HR 及其 95%CI：5.8μg/m3：1.12；1.04-1.22），也与首次住院相关（1.10；1.01-1.20），在既往有哮喘或慢性阻塞性肺疾病（COPD）住院史的人群中风险最高（1.41；1.15-2.07）或 COPD（1.30；1.07-1.52）。
长期接触交通相关空气污染会增加老年人哮喘住院的风险。既往有哮喘或 COPD 住院史的人群对此更为敏感。
