Effects of air pollution on adults with chronic obstructive pulmonary disease.

Few studies have been conducted on the effects of air pollution on patients with chronic obstructive pulmonary disease (COPD). During a 14-mo period, 39 Parisian adults with severe COPD were monitored by their physicians. Daily levels of 4 air pollutants were provided by an urban air-quality network. Exacerbation of COPD was associated only with ozone (O3) (odds ratio [OR] = 1.44 for a 10-microg/m3 increase in O3; 95% confidence interval [CI] = 1.14, 1.82), with a lag of 2-3 days. The effect of O3 was greater in patients whose carbon dioxide pressure (PaCO2) was higher than 43 mm Hg (OR = 1.83; 95% CI = 1.36, 2.47) vs. those with a lower PaCO2 (OR = 1.26; 95% CI = 0.90, 1.77). The effect of O3 was unchanged, regardless of the maintenance medications used. The only air pollutant to which patients with severe COPD were particularly sensitive was O3.