title: Early-life air pollution and asthma risk in minority children. The GALA II and SAGE II studies.
abstract: BACKGROUND
  Air pollution is a known asthma trigger and has been associated with short-term asthma symptoms, airway inflammation, decreased lung function, and reduced response to asthma rescue medications.
  
  
  OBJECTIVE
  To assess a causal relationship between air pollution and childhood asthma using data that address temporality by estimating air pollution exposures before the development of asthma and to establish the generalizability of the association by studying diverse racial/ethnic populations in different geographic regions.
  
  
  METHODS
  This study included Latino (n = 3,343) and African American (n = 977) participants with and without asthma from five urban regions in the mainland United States and Puerto Rico. Residential history and data from local ambient air monitoring stations were used to estimate average annual exposure to five air pollutants: ozone, nitrogen dioxide (NO₂), sulfur dioxide, particulate matter not greater than 10 μm in diameter, and particulate matter not greater than 2.5 μm in diameter. Within each region, we performed logistic regression to determine the relationship between early-life exposure to air pollutants and subsequent asthma diagnosis. A random-effects model was used to combine the region-specific effects and generate summary odds ratios for each pollutant.
  
  
  RESULTS
  After adjustment for confounders, a 5-ppb increase in average NO₂ during the first year of life was associated with an odds ratio of 1.17 for physician-diagnosed asthma (95% confidence interval, 1.04-1.31).
  
  
  CONCLUSIONS
  Early-life NO₂ exposure is associated with childhood asthma in Latinos and African Americans. These results add to a growing body of evidence that traffic-related pollutants may be causally related to childhood asthma.
authors.affiliation: Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA 94158, USA. katherine.nishimura@ucsf.edu
authors.forename: Katherine K
authors.initials: KK
authors.lastname: Nishimura
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Galanter
authors.forename: Lindsey A
authors.initials: LA
authors.lastname: Roth
authors.forename: Sam S
authors.initials: SS
authors.lastname: Oh
authors.forename: Neeta
authors.initials: N
authors.lastname: Thakur
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Nguyen
authors.forename: Shannon
authors.initials: S
authors.lastname: Thyne
authors.forename: Harold J
authors.initials: HJ
authors.lastname: Farber
authors.forename: Denise
authors.initials: D
authors.lastname: Serebrisky
authors.forename: Rajesh
authors.initials: R
authors.lastname: Kumar
authors.forename: Emerita
authors.initials: E
authors.lastname: Brigino-Buenaventura
authors.forename: Adam
authors.initials: A
authors.lastname: Davis
authors.forename: Michael A
authors.initials: MA
authors.lastname: LeNoir
authors.forename: Kelley
authors.initials: K
authors.lastname: Meade
authors.forename: William
authors.initials: W
authors.lastname: Rodriguez-Cintron
authors.forename: Pedro C
authors.initials: PC
authors.lastname: Avila
authors.forename: Luisa N
authors.initials: LN
authors.lastname: Borrell
authors.forename: Kirsten
authors.initials: K
authors.lastname: Bibbins-Domingo
authors.forename: Jose R
authors.initials: JR
authors.lastname: Rodriguez-Santana
authors.forename: Śaunak
authors.initials: Ś
authors.lastname: Sen
authors.forename: Fred
authors.initials: F
authors.lastname: Lurmann
authors.forename: John R
authors.initials: JR
authors.lastname: Balmes
authors.forename: Esteban G
authors.initials: EG
authors.lastname: Burchard
mesh_terms: D000293:Adolescent; D001741:Black or African American; D000367:Age Factors; D000393:Air Pollutants / Q000009:adverse effects*; D000397:Air Pollution; D001249:Asthma / Q000208:ethnology* / Q000209:etiology; D002648:Child; D016001:Confidence Intervals; D004784:Environmental Monitoring / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006630:Hispanic or Latino; D006801:Humans; D008297:Male; D008913:Minority Groups; D016017:Odds Ratio; D052638:Particulate Matter / Q000009:adverse effects*; D011647:Puerto Rico / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014505:Urban Population; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter