TABLE 3.
EFFECT OF TRP ON LUNG FUNCTION MEASUREMENTS, STRATIFIED BY PARENTAL STRESS LEVEL (HIGH OR LOW)*
| TRP | Location | Main Effect % Change (95% CI) | Low Parental Stress % Change (95% CI) | High Parental Stress % Change (95% CI) | Interaction P Value |
| FVC | |||||
| NOx | Home | −2.31 (−3.8 to −0.8) | 0.02 (−2.1 to 2.2) | −4.73 (−6.7 to −2.7) | <0.01 |
| School | −0.98 (−3 to 1) | 1.04 (−1.7 to 3.9) | −3.01 (−5.9 to −0.1) | 0.07 | |
| NO | Home | −2.60 (−4.2 to −1) | −0.04 (−2.4 to 2.4) | −4.84 (−6.9 to −2.8) | <0.01 |
| School | −1.39 (−3.5 to 0.8) | 0.82 (−2.2 to 4) | −3.30 (−6.3 to −0.2) | 0.04 | |
| NO2 | Home | −2.00 (−3.4 to −0.6) | 0.07 (−1.9 to 2) | −4.55 (−6.5 to −2.6) | 0.02 |
| School | −0.59 (−2.5 to 1.3) | 1.29 (−1.3 to 4) | −2.68 (−5.4 to 0.1) | >0.10 | |
| FEV1 | |||||
| NOx | Home | −1.85 (−3.3 to −0.4) | 0.62 (−1.6 to 2.9) | −4.47 (−6.5 to −2.4) | <0.01 |
| School | −0.15 (−2.2 to 1.9) | 2.52 (−0.3 to 5.5) | −2.77 (−5.7 to 0.3) | 0.07 | |
| NO | Home | −2.09 (−3.7 to −0.5) | 0.75 (−1.7 to 3.3) | −4.61 (−6.7 to −2.5) | <0.01 |
| School | −0.40 (−2.6 to 1.8) | 2.62 (−0.5 to 5.8) | −3.03 (−6.1 to 0.2) | 0.04 | |
| NO2 | Home | −1.60 (−3 to −0.2) | 0.54 (−1.4 to 2.5) | −4.31 (−6.3 to −2.3) | 0.02 |
| School | 0.06 (−1.9 to 2) | 2.43 (−0.3 to 5.2) | −2.48 (−5.3 to 0.4) | >0.10 | |
| MMEF | |||||
| NOx | Home | −0.72 (−3.7 to 2.4) | 0.85 (−3.4 to 5.3) | −2.57 (−6.7 to 1.8) | >0.10 |
| School | 1.21 (−2.9 to 5.5) | 3.28 (−2.4 to 9.2) | −0.82 (−6.8 to 5.6) | >0.10 | |
| NO | Home | −1.09 (−4.3 to 2.2) | 0.77 (−4 to 5.8) | −2.90 (−7.2 to 1.6) | >0.10 |
| School | 0.95 (−3.4 to 5.5) | 3.39 (−2.7 to 9.9) | −1.15 (−7.5 to 5.6) | >0.10 | |
| NO2 | Home | −0.55 (−3.4 to 2.4) | 0.88 (−3 to 4.9) | −2.60 (−6.7 to 1.7) | >0.10 |
| School | 1.19 (−2.7 to 5.3) | 2.99 (−2.3 to 8.6) | −0.76 (−6.5 to 5.4) | >0.10 | |
Definition of abbreviations: CI = confidence interval; MMEF = FEF25–75; NO = nitric oxide; NO2 = nitrogen dioxide; NOx = total oxides of nitrogen; TRP = traffic-related pollution.
*
Models adjusted for log height and square term for log height, body mass index and square term for body mass index, sex, age, age–sex interaction, race, Hispanic ethnicity, respiratory illness at time of lung function, field technician, and community. Percent (%) change was scaled to 2 SD (NOx = 21.8 ppb; NO = 16.2 ppb; and NO2 = 7.3 ppb) of the TRP difference between home and school (averaged across schools).