Table 5

 Logistic regression of pollutants for risk of COPD

Crude OR (95% CI)p ValueAdjusted OR (95% CI)†p Value
SO2, sulphur dioxide; NO2, nitrogen dioxide; PM10, particulate matter with aerodynamic diameter ⩽10 μm; CO, carbon monoxide.
*Scores from principal components analysis of concentrations of SO2, NO2, PM10 and CO.
†Adjusted by area, age group, environmental tobacco smoke exposure, occupational exposure to dust, respiratory disease in family, cough in childhood and local exhaust ventilation in kitchen.
Pollutants*1.27 (0.89 to 1.81)0.1931.29 (0.83 to 2.01)0.361
SO24.79 (2.51 to 9.16)<0.0011.80 (1.04 to 3.11)0.036
NO22.27 (1.86 to 2.78)<0.0011.28 (0.79 to 2.09)0.321
PM101.66 (1.26 to 2.19)<0.0011.10 (0.93 to 1.30)0.254
CO1.15 (1.10 to 1.20)<0.0011.01 (0.98 to 1.04)0.379