Table 4. Estimated Absolute Change in Children’s Lung Function Test Measurements Associated With 4-Year Mean Ambient Air Pollutant Concentrations Estimated Using a Spatial Statistical Model Stratified by Breastfed Status.
| Pollutant | β (95% CI)a,b | P Value for Interaction | |
|---|---|---|---|
| Not Breastfed (n = 1989) | Breastfed (n = 4751) | ||
| FVC | |||
| PM1 | −240.46 (−288.71 to −192.21) | −38.21 (−69.27 to −7.16) | <.001 |
| PM2.5 | −217.97 (−259.95 to −175.99) | −42.02 (−68.78 to −15.27) | <.001 |
| PM10 | −185.99 (−224.08 to −147.89) | −56.48 (−81.29 to −31.68) | .003 |
| NO2 | −179.26 (−221.32 to −137.20) | −88.91 (−116.93 to −60.88) | .42 |
| FEV1 | |||
| PM1 | −201.37 (−242.08 to −160.65) | −30.30 (−57.66 to −2.94) | <.001 |
| PM2.5 | −181.68 (−217.06 to −146.30) | −33.86 (−57.57 to −10.15) | <.001 |
| PM10 | −154.14 (−186.37 to −121.90) | −48.63 (−70.77 to −26.49) | <.001 |
| NO2 | −150.26 (−186.14 to −114.39) | −79.99 (−104.91 to −55.06) | .16 |
| PEF | |||
| PM1 | −333.29 (−438.21 to −228.37) | −58.28 (−125.54 to 8.98) | <.001 |
| PM2.5 | −273.82 (−363.94 to −183.69) | −65.96 (−124.14 to −7.78) | .001 |
| PM10 | −214.86 (−295.23 to −134.48) | −79.68 (−133.81 to −25.55) | .009 |
| NO2 | −206.06 (−294.94 to −117.18) | −96.96 (−157.95 to −35.98) | .06 |
| MMEF | |||
| PM1 | −127.42 (−208.01 to −46.84) | −13.12 (−65.24 to 39.00) | .03 |
| PM2.5 | −101.86 (−171.22 to −32.49) | −23.95 (−69.18 to 21.28) | .06 |
| PM10 | −77.17 (−139.14 to −15.19) | −38.00 (−80.34 to 4.34) | .19 |
| NO2 | −66.16 (−134.19 to 1.87) | −53.38 (−101.08 to −5.69) | .57 |
Abbreviations: FEV1, forced expiratory volume in the first second of expiration; FVC, forced vital capacity; MMEF, maximum midexpiratory flow rate; NO2, nitrogen dioxide; PEF, peak expiratory flow rate; PM1, airborne particulate matter with a diameter ≤1 μm; PM2.5, airborne particulate matter with a diameter ≤2.5 μm; PM10, airborne particulate matter with a diameter ≤10 μm.
Adjusted for age, sex, height, birth weight, preterm birth, parental education, annual family income, exercise per week, passive smoke exposure, home coal use, presence of a house pet, home renovation in the past 2 years, area of residence per person, asthma diagnosis, family history of atopy, and short-term air pollution concentrations.
Effect expressed for a 1–interquartile range change in ambient concentration for each pollutant (PM1, 13.1 μg/m3; PM2.5, 10.0 μg/m3; PM10, 13.8 μg/m3; and NO2, 7.3 μg/m3).