Effects of measures of near-roadway air pollution on lung function level
| FEV1† | FVC† | |||
|---|---|---|---|---|
| % difference | 95% CI | % difference | 95% CI | |
| Freeway | ||||
| >1500 m | Ref | Ref | ||
| 1000–1500 m | 1.63 | (−0.05 to 3.34) | 0.99 | (−0.65 to 2.66) |
| 500–1000 m | −0.50 | (−2.05 to 1.07) | −1.01 | (−2.52 to 0.53) |
| <500 m | −1.06 | (−2.55 to 0.45) | −1.96 | (−3.41 to −0.49)** |
| Trend (p value) | 0.09 | 0.004 | ||
| Major road | ||||
| >300 m | Ref | Ref | ||
| 150–300 m | −0.56 | (−1.90 to 0.79) | −0.69 | (−2.00 to 0.65) |
| 75–150 m | −0.50 | (−2.04 to 1.06) | −0.82 | (−2.32 to 0.72) |
| <75 m | −1.58 | (−3.21 to 0.09) | −1.53 | (−3.14 to 0.11) |
| Trend (p value) | 0.09 | 0.06 | ||
| Predicted near-roadway pollution‡ | ||||
| NO2 | −1.00 | (−2.08 to 0.09) | −1.40 | (−2.46 to −0.33)* |
| NO | −1.19 | (−2.27 to −0.09)* | −1.68 | (−2.74 to −0.60)*** |
| NOx | −1.10 | (−2.19 to −0.01)* | −1.56 | (−2.62 to −0.49)*** |
†All models include adjustments for log of height and its squared value, body mass index (BMI) and BMI2, sex, age, sex×age interaction, race, Hispanic ethnicity, respiratory illness at time of test, field technician and study community.
‡Near-roadway residential pollutants were scaled to 2 SDs of their respective community mean centred distributions (6.4 ppb for NO2, 12.3 ppb for NO and 17.9 ppb for NOx).
*p<0.05, **p<0.01, ***p<0.005.
FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; NO, nitric oxide; NO2, nitrogen dioxide; NOx, total nitrogen oxides.