Table 5
Association between long-term exposure to air pollution and lifetime prevalences of infections, asthmatic and allergic symptoms
| Exposure variable | Adjusted* odds ratios of symptoms associated with interquartile range of air pollution variables (symptom variable) | |||||
|---|---|---|---|---|---|---|
| Wheeze | Cough without infection | Dry cough at night | Asthmatic/spastic/obstructive bronchitis | Respiratory infections | Sneezing, runny/stuffed nose | |
| NA, not applicable; NO2, nitrogen dioxide; PM2.5, particulate matter with a 50% cut-off aerodynamic diameter of 2.5 µm. | ||||||
| *Adjusted for sex, parental atopy, maternal education, siblings, environmental tobacco smoke at home, use of gas for cooking, home dampness, indoor moulds and keeping pets. | ||||||
| At the age of 1 year | ||||||
| n = 3037 | n = 2908 | n = 3056 | n = 3059 | n = 3052 | n = 3067 | |
| PM2.5 (per 1.04 μg/m3) | 1.01 (0.87 to 1.18) | 1.05 (0.88 to 1.25) | 1.08 (0.86 to 1.27) | 1.04 (0.90 to 1.29) | 1.05 (0.88 to 1.22) | 1.16 (1.01 to 1.34) |
| PM2.5 absorbance (per 0.22×10−5/m) | 0.97 (0.77 to 1.23) | 1.16 (0.87 to 1.54) | 1.09 (0.78 to 1.51) | 1.14 (0.88 to 1.48) | 1.03 (0.86 to 1.24) | 1.30 (1.03 to 1.65) |
| NO2 (per 5.7 μg/m3) | 1.09 (0.88 to 1.35) | 1.15 (0.88 to 1.51) | 1.34 (1.00 to 1.81) | 1.30 (1.03 to 1.66) | 1.06 (0.89 to 1.26) | 1.14 (0.90 to 1.43) |
| Distance to nearest main road <50 m (yes v no) | 1.14 (0.92 to 1.42) | 0.74 (0.55 to 1.00) | 0.84 (0.61 to 1.16) | 1.12 (0.88 to 1.44) | 1.03 (0.86 to 1.23) | 1.10 (0.87 to 1.39) |
| At the age of 2 years | ||||||
| n = 2882 | n = 2866 | n = 2861 | n = 3021 | n = 2907 | ||
| PM2.5 (per 1.04 µg/m3) | 1.10 (0.96 to 1.25) | NA | 1.03 (0.89 to 1.19) | 1.05 (0.92 to 1.20) | 1.09 (0.94 to 1.27) | 1.19 (1.04 to 1.36) |
| PM2.5 absorbance (per 0.22×10−5/m) | 1.09 (0.90 to 1.33) | NA | 1.18 (0.93 to 1.50) | 0.85 (0.31 to 2.34) | 1.05 (0.79 to 1.39) | 1.27 (1.04 to 1.56) |
| NO2 (per 5.7 μg/m3) | 1.09 (0.90 to 1.31) | NA | 1.16 (0.92 to 1.47) | 0.82 (0.33 to 2.03) | 1.08 (0.83 to 1.42) | 1.09 (0.89 to 1.33) |
| Distance to nearest main road <50 m (yes v no) | 1.06 (0.88 to 1.27) | NA | 0.93 (0.73 to 1.18) | 1.23 (1.00 to 1.51) | 1.15 (0.87 to 1.53) | 1.24 (1.01 to 1.51) |
