title: Long-term exposure to PM10 and NO2 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.
  
  
  OBJECTIVE
  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 (sR(aw)) 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 sR(aw) 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.
authors.affiliation: Centre for Occupational and Environmental Health, Health Sciences Group, School of Community-Based Medicine, Manchester Academic Health Sciences Centre, The University of Manchester, Manchester, United Kingdom.
authors.forename: Anna
authors.initials: A
authors.lastname: Mölter
authors.forename: Raymond M
authors.initials: RM
authors.lastname: Agius
authors.forename: Frank
authors.initials: F
authors.lastname: de Vocht
authors.forename: Sarah
authors.initials: S
authors.lastname: Lindley
authors.forename: William
authors.initials: W
authors.lastname: Gerrard
authors.forename: Lesley
authors.initials: L
authors.lastname: Lowe
authors.forename: Danielle
authors.initials: D
authors.lastname: Belgrave
authors.forename: Adnan
authors.initials: A
authors.lastname: Custovic
authors.forename: Angela
authors.initials: A
authors.lastname: Simpson
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000403:Airway Resistance / Q000187:drug effects*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology*; D008297:Male; D009585:Nitrogen Dioxide / Q000633:toxicity*; D052638:Particulate Matter / Q000633:toxicity*; D013147:Spirometry
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D009585:Nitrogen Dioxide