AJRCCM：室内空气污染或导致COPD恶化

　　美国学者的一项研究显示，包括PM_2.5 和NO₂在内的室内污染暴露，与呼吸系统症状和COPD恶化风险增加相关。将来的调查应该包括干预研究，将提高室内空气质量作为改善COPD患者健康预后的一种新方法。相关论文2013年5月15日在线发表于《美国呼吸与重症医学》杂志。

　　该研究纳入曾经吸烟的COPD患者，持续一周监测其卧室和主要生活区域的室内空气污染指标，作为基线指标，在之后3个月和6个月时分别再进行监测。参与者每次需要完成肺功能检查和一个评估呼吸系统症状的问卷调查，随后通过对诊所来访者进行问卷调查和每月电话访谈了解其症状。  

　　结果显示，参与研究的84例中度和重度COPD患者，预测其平均一秒用力呼气容积(FEV₁)为48.6%。平均卧室内的PM_2.5和NO₂浓度分别为11.4±13.3 µg/m³和10.8±10.6 ppb，主要生活区域的PM_2.5和NO₂浓度 分别为12.2±12.2 µg/m³ 和12.2±11.8 ppb。主要生活区域的PM_2.5浓度增加与呼吸系统症状、抢救药物使用、严重COPD恶化风险增加相关。主要生活区域的NO₂浓度与呼吸困难加重呈独立相关。卧室内NO₂浓度的增加与夜间症状和严重COPD恶化风险增加相关。

In-home air pollution is linked to respiratory morbidity in former smokers with chronic obstructive pulmonary disease.
Rationale
The effect of indoor air pollutants on respiratory morbidity among patients with chronic obstructive pulmonary disease (COPD) in developed countries is uncertain.
Objectives
The first longitudinal study to investigate the independent effects of indoor particulate matter (PM) and nitrogen dioxide (NO2) concentrations on COPD morbidity in a periurban community.
Methods
Former smokers with COPD were recruited and indoor air was monitored over a 1-week period in the participant's bedroom and main living area at baseline, 3 months, and 6 months. At each visit, participants completed spirometry and questionnaires assessing respiratory symptoms. Exacerbations were assessed by questionnaires administered at clinic visits and monthly telephone calls.
Measurements and Main Results
Participants (n = 84) had moderate or severe COPD with a mean FEV1 of 48.6% predicted. The mean (± SD) indoor PM2.5 and NO2 concentrations were 11.4 ± 13.3 µg/m(3) and 10.8 ± 10.6 ppb in the bedroom, and 12.2 ± 12.2 µg/m(3) and 12.2 ± 11.8 ppb in the main living area. Increases in PM2.5 concentrations in the main living area were associated with increases in respiratory symptoms, rescue medication use, and risk of severe COPD exacerbations. Increases in NO2 concentrations in the main living area were independently associated with worse dyspnea. Increases in bedroom NO2 concentrations were associated with increases in nocturnal symptoms and risk of severe COPD exacerbations.
Conclusions
Indoor pollutant exposure, including PM2.5 and NO2, was associated with increased respiratory symptoms and risk of COPD exacerbation. Future investigations should include intervention studies that optimize indoor air quality as a novel therapeutic approach to improving COPD health outcomes.