Table 3.
Covariate-adjusteda associations of traffic-related air pollution in pregnancy and in mid-childhood with adiposity and cardiometabolic health in mid-childhood (median: 7.7 years of age). For black carbon, fine particulate matter, and traffic density exposures, estimates are mean difference (95% confidence intervals) in outcome for each interquartile range increment in exposure.b For roadway proximity, estimates are mean difference (95% confidence intervals) for each proximate category of roadway proximity versus ≥200 m. Estimates with 95% confidence intervals that do not cross the null are bolded.
| BMI z-score (z-units) |
Total fat mass (kg) |
Truncal fat mass (kg) |
Leptin (% change) |
Adiponectin (% change) |
HOMA-IR (% change) |
|
|---|---|---|---|---|---|---|
| Black carbon (BC) exposure (µg/m3) | ||||||
| Third trimester | −0.0 (−0.1, 0.1) | −0.2 (−0.5, 0.2) | −0.1 (−0.2, 0.1) | 4.0 (−6.6, 15.7) | 2.4 (−4.9, 10.3) | 1.1 (−8.8, 12.1) |
| Year prior to mid-childhood visit | −0.1 (−0.2, 0.0) | 0.0 (−0.3, 0.4) | 0.0 (−0.1, 0.2) | 3.5 (−6.8, 15.0) | 1.3 (−5.9, 9.0) | 3.9 (−5.9, 14.6) |
| Fine particulate (PM2.5) exposure (µg/m3) | ||||||
| Third trimester | −0.0 (−0.1, 0.0) | −0.2 (−0.6, 0.1) | −0.1 (−0.2, 0.1) | −5.1 (−14.7, 5.6) | −5.0 (−11.7, 2.3) | 2.8 (−6.6, 13.0) |
| Year prior to mid-childhood visit | −0.2 (−0.4, −0.1) | −0.6 (−1.2, −0.1) | −0.3 (−0.5, −0.0) | −12.1 (−24.9, 2.8) | −2.8 (−13.0, 8.6) | −17.8 (−29.2, −4.7) |
| Near-residence traffic density | ||||||
| Birth address | 0.0 (−0.0, 0.1) | 0.0 (−0.2, 0.2) | −0.0 (−0.1, 0.1) | 4.0 (−1.3, 9.6) | 0.6 (−3.0, 4.3) | −5.7 (−10.1, −1.1) |
| Mid-childhood address | −0.0 (−0.1, 0.0) | 0.0 (−0.1, 0.2) | 0.0 (−0.1, 0.1) | 1.9 (−2.6, 6.6) | −0.9 (−4.1, 2.3) | 0.1 (−4.2, 4.5) |
| Proximity to major roadway, birth address | ||||||
| <50 m | 0.1 (−0.2, 0.5) | 2.1 (0.8, 3.5) | 0.9 (0.4, 1.5) | 78.3 (18.5, 168.3) | −13.2 (−34.7, 15.4) | −0.2 (−33.6, 49.8) |
| 50–<100 m | −0.0 (−0.4, 0.4) | −0.5 (−2.0, 1.0) | −0.3 (−0.9, 0.4) | −4.9 (−36.0, 41.3) | −1.2 (−25.0, 30.2) | −32.4 (−53.6, −1.4) |
| 100–<200 m | 0.3 (0.0, 0.5) | 1.1 (0.1, 2.0) | 0.4 (−0.0, 0.8) | 1.2 (−21.5, 30.5) | 1.0 (−15.4, 20.5) | −6.3 (−27.2, 20.7) |
| ≥200 m | Reference | Reference | Reference | Reference | Reference | Reference |
| Proximity to major roadway, mid-childhood address | ||||||
| <50 m | −0.0 (−0.4, 0.4) | 0.1 (−1.4, 1.6) | 0.0 (−0.6, 0.7) | 46.6 (−5.3, 127.1) | −13.5 (−36.1, 17.2) | −1.8 (−36.6, 52.3) |
| 50–<100 m | −0.1 (−0.5, 0.3) | −1.0 (−2.5, 0.5) | −0.4 (−1.1, 0.2) | −19.1 (−45.5, 20.0) | 0.4 (−23.6, 32.0) | −13.1 (−41.3, 28.6) |
| 100–<200 m | 0.1 (−0.2, 0.3) | 0.4 (−0.6, 1.5) | 0.2 (−0.3, 0.6) | 8.6 (−18.0, 43.9) | 5.6 (−13.1, 28.3) | −5.8 (−29.4, 25.8) |
| ≥200 m | Reference | Reference | Reference | Reference | Reference | Reference |
Model adjusted for characteristics of child (age, sex, race/ethnicity), mother (age, education, smoking during pregnancy), neighborhood (census tract median income), as well as season and date of health outcome.
Interquartile range= 0.33 µg/m3 for third trimester BC, 0.20 µg/m3 for BC during the year prior to the mid-childhood visit, 2.20 µg/m3 for third trimester PM2.5, 1.66 µg/m3 for PM2.5 during the year prior to the mid-childhood visit, 1,454 km*vehicles/day for traffic density at birth, and 1,186 km*vehicles/day for mid-childhood traffic density.