Long-term Exposure to PM ₁₀ and NO ₂ in Association with Lung Volume and Airway Resistance in the MAAS Birth Cohort

Abstract

Background: Findings from previous studies on the effects of air pollution exposure on lung function during childhood have been inconsistent. A common limitation has been the quality of exposure data used, and few studies have modeled exposure longitudinally throughout early life.Objectives: We sought to study the long-term effects of exposure to particulate matter with an aerodynamic diameter ≤ 10 μm (PM10) and to nitrogen dioxide (NO2) on specific airway resistance (sRaw) and forced expiratory volume in 1 sec (FEV1) before and after bronchodilator treatment. Subjects were from the Manchester Asthma and Allergy Study (MAAS) birth cohort (n = 1,185).Methods: Spirometry was performed during clinic visits at ages 3, 5, 8, and 11 years. Individual-level PM10 and NO2 exposures were estimated from birth to 11 years of age through a microenvironmental exposure model. Longitudinal and cross-sectional associations were estimated using generalized estimating equations and multivariable linear regression models.Results: Lifetime exposure to PM10 and NO2 was associated with significantly less growth in FEV1 (percent predicted) over time, both before (–1.37%; 95% CI: –2.52, –0.23 for a 1-unit increase in PM10 and –0.83%; 95% CI: –1.39, –0.28 for a 1-unit increase in NO2) and after bronchodilator treatment (–3.59%; 95% CI: –5.36, –1.83 and –1.20%; 95% CI: –1.97, –0.43, respectively). We found no association between lifetime exposure and sRaw over time. Cross-sectional analyses of detailed exposure estimates for the summer and winter before 11 years of age and lung function at 11 years indicated no significant associations.Conclusions: Long-term PM10 and NO2 exposures were associated with small but statistically significant reductions in lung volume growth in children of elementary-school age.Citation: Mölter A, Agius RM, de Vocht F, Lindley S, Gerrard W, Lowe L, Belgrave D, Custovic A, Simpson A. 2013. Long-term exposure to PM10 and NO2 in association with lung volume and airway resistance in the MAAS birth cohort. Environ Health Perspect 121:1232–1238. http://dx.doi.org/10.1289/ehp.1205961

Allergy in severe asthma

“…A multicenter birth cohort study (ESCAPE) showed an association between estimated levels of NO 2 and PM 2.5 and decreases in FEV 1 (139). In another birth cohort study (MAAS), lifetime exposure to PM 10 and NO 2 was associated with significantly less growth in FEV 1 over time (140). In the same cohort, no association was found between long-term exposure to PM 10 and NO 2 and the prevalence of asthma or wheeze (142).…”

“…Larger-scale studies also demonstrated an adverse effect of outdoor air pollution on lung function (139)(140)(141). A multicenter birth cohort study (ESCAPE) showed an association between estimated levels of NO 2 and PM 2.5 and decreases in FEV 1 (139).…”

Environmental Pollution and the Developing Lung

“…Retention of a subject cohort to study over several years is difficult, and results may be confounded, particularly if families move to a region with different exposures. 79 However, despite the methodologic problems, there is strong evidence from at least 9 selected and well-controlled longitudinal studies (reviewed in Table 2, [71][72][73][74][75][76][77][78][79], that children exposed to greater concentrations of complex air pollutants are at risk for not achieving their optimal lung development by the time they attain adulthood.…”

Intrauterine and early postnatal exposure to outdoor air pollution and lung function at preschool age

“…To date, few studies have assessed lung function at preschool age—most of them assessing airway resistance—in relation to exposure to air pollution early in life with inconsistent results 7 8. Furthermore, very little work has been done on assessing the impact of exposure to air pollution during the prenatal period on lung function later in life.…”