Higgins B G, Francis H C, Yates C J, Warburton C J, Fletcher A M, Reid J A, Pickering C A, Woodcock A A
North West Lung Centre, Wythenshawe Hospital, Manchester, UK.
Thorax. 1995 Feb;50(2):149-55. doi: 10.1136/thx.50.2.149.
Evidence from laboratory studies suggests that air pollution can produce bronchoconstriction and respiratory symptoms in selected subjects, but the relevance of these findings to exposure to natural pollution is unclear. This study was performed to determine whether air pollution at typical levels found in the UK has demonstrable effects on respiratory function and symptoms in subjects with airways disease.
Seventy five adult patients with diagnoses of asthma or chronic obstructive pulmonary disease (COPD) were studied for a period of four weeks during which they kept records of their peak expiratory flow (PEF) rates, symptoms (wheeze, dyspnoea, cough, throat and eye irritation), and bronchodilator use. Thirty six patients in whom the provocative dose of methacholine causing a 20% fall in FEV1 was below 12.25 mumol were classified as reactors. Ambient air pollution was measured with absorption spectroscopy.
There were modest but significant increases in PEF variability, bronchodilator use, and wheeze with increasing sulphur dioxide levels; bronchodilator use, dyspnoea, eye irritation, and minimum PEF readings were related to ozone levels. In the subgroup of reactors falls in mean and minimum peak flow and increases in wheeze, dyspnoea, and bronchodilator use were associated with increases in levels of both sulphur dioxide and ozone. Some associations were seen with pollution levels on the same day, but for others the pollution effects appeared to be delayed by 24 or 48 hours. Pollution levels did not breach the WHO guide levels during the course of the study.
Increases in environmental levels of ozone and sulphur dioxide are associated with adverse changes in peak flow measurements and both ocular and respiratory symptoms in subjects with obstructive airways disease. Although the peak flow and symptom changes were modest, they occurred at pollution levels below current WHO guide levels.
实验室研究证据表明，空气污染可使特定人群出现支气管收缩和呼吸道症状，但这些研究结果与自然污染暴露的相关性尚不清楚。本研究旨在确定英国常见的典型空气污染水平是否会对气道疾病患者的呼吸功能和症状产生明显影响。
对75例诊断为哮喘或慢性阻塞性肺疾病（COPD）的成年患者进行了为期四周的研究，在此期间他们记录自己的呼气峰值流速（PEF）、症状（喘息、呼吸困难、咳嗽、咽喉和眼睛刺激）以及支气管扩张剂的使用情况。36例对乙酰甲胆碱激发剂量导致第一秒用力呼气容积（FEV1）下降20%时低于12.25微摩尔的患者被归类为反应者。采用吸收光谱法测量环境空气污染情况。
随着二氧化硫水平升高，PEF变异性、支气管扩张剂使用和喘息有适度但显著的增加；支气管扩张剂使用、呼吸困难、眼睛刺激和最低PEF读数与臭氧水平有关。在反应者亚组中，平均和最低峰值流速下降以及喘息、呼吸困难和支气管扩张剂使用增加与二氧化硫和臭氧水平升高有关。一些关联在同一天的污染水平中可见，但其他一些污染影响似乎延迟了24或48小时。在研究过程中，污染水平未超过世界卫生组织的指导水平。
环境中臭氧和二氧化硫水平升高与阻塞性气道疾病患者的峰值流速测量以及眼部和呼吸道症状的不良变化有关。尽管峰值流速和症状变化较小，但它们发生在低于当前世界卫生组织指导水平的污染水平下。
