Table 3.

Two pollutant models for the associations of asthma severity and different air pollutants for asthmatics with asthma onset at > 12 years (N = 413)

	PM10 with NO2, aOR (95 % CI)	PM10 with SO2, aOR (95 % CI)	PM10 with CO, aOR (95 % CI)
Severity score	2.06 (1.02 – 4.18)	2.30 (1.01 – 5.21)	3.20 (1.52 – 6.73)

aOR adjusted odds ratio; BMI body mass index; CI confidence interval

The odds ratios were adjusted with age, sex, BMI, education level and family income level. Those exposed to the pollutant concentrations lower than medians were used as reference groups. Numbers did not total 450 because of missing data