Association of Changes in Air Quality with Incident Asthma in Children in California, 1993–2014

Details

• Personal Author:
  Berhane KT ; Chen Z ; Garcia E ; Gilliland FD ; Islam T ; McConnell R ; Urman R
• Description:
  Importance: Exposure to air pollutants is a well-established cause of asthma exacerbation in children; whether air pollutants play a role in the development of childhood asthma, however, remains uncertain. Objective: To examine whether decreasing regional air pollutants were associated with reduced incidence of childhood asthma. Design, Setting, and Participants: A multilevel longitudinal cohort drawn from 3 waves of the Southern California Children's Health Study over a period of air pollution decline. Each cohort was followed up from 4th to 12th grade (8 years): 1993-2001, 1996-2004, and 2006-2014. Final follow-up for these data was June 2014. Population-based recruitment was from public elementary schools. A total of 4140 children with no history of asthma and residing in 1 of 9 Children's Health Study communities at baseline were included. Exposures: Annual mean community-level ozone, nitrogen dioxide, and particulate matter less than 10 µm (PM10) and less than 2.5 µm (PM2.5) in the baseline year for each of 3 cohorts. Main Outcomes and Measures: Prospectively identified incident asthma, collected via questionnaires during follow-up. Results: Among the 4140 children included in this study (mean [SD] age at baseline, 9.5 [0.6] years; 52.6% female [n = 2179]; 58.6% white [n = 2273]; and 42.2% Hispanic [n = 1686]), 525 incident asthma cases were identified. For nitrogen dioxide, the incidence rate ratio (IRR) for asthma was 0.80 (95% CI, 0.71-0.90) for a median reduction of 4.3 parts per billion, with an absolute incidence rate decrease of 0.83 cases per 100 person-years. For PM2.5, the IRR was 0.81 (95% CI, 0.67-0.98) for a median reduction of 8.1 µg/m3, with an absolute incidence rate decrease of 1.53 cases per 100 person-years. For ozone, the IRR for asthma was 0.85 (95% CI, 0.71-1.02) for a median reduction of 8.9 parts per billion, with an absolute incidence rate decrease of 0.78 cases per 100 person-years. For PM10, the IRR was 0.93 (95% CI, 0.82-1.07) for a median reduction of 4.0 µg/m3, with an absolute incidence rate decrease of 0.46 cases per 100 person-years. Conclusions and Relevance: Among children in Southern California, decreases in ambient nitrogen dioxide and PM2.5 between 1993 and 2014 were significantly associated with lower asthma incidence. There were no statistically significant associations for ozone or PM10. [Description provided by NIOSH]
• Subjects:
  Air Pollutants, Occupational Asthma Asthma, Occupational Cohort Studies Community Health Services Nitrogen Dioxide Occupational Health Ozone Particulate Matter Safety
• Keywords:
  Air Pollutants Children Cohort Studies Community Health Longitudinal Study Nitrogen Dioxide Particulates
• ISSN:
  0098-7484
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  321
• Issue:
  19
• NIOSHTIC Number:
  nn:20063107
• Citation:
  JAMA 2019 May; 321(19):1906-1915
• Contact Point Address:
  Erika Garcia, PhD, Department of Preventive Medicine, Keck School of Medicine, University of Southern California, 2001 N Soto St, SSB1 225F MC 9237, Los Angeles, CA 90089-9237
• Email:
  garc991@usc.edu
• CAS Registry Number:
  Nitrogen dioxide (CAS RN 10102-44-0) ; Ozone (CAS RN 10028-15-6)
• Federal Fiscal Year:
  2019
• Performing Organization:
  University of California, Berkeley
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Journal of the American Medical Association
• End Date:
  20250630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:75bc5b6b17b1c3e01f9a74f8ab0deae66d25e05400782054effc6c5326eee1fc668e0fca92cecc00e2da6f90410a4d425750726a521d4db2ee7795c36932beee
• Download URL:
  https://stacks.cdc.gov/view/cdc/226230/cdc_226230_DS1.pdf
• File Type:
  [PDF - 436.66 KB ]