Air Pollution, Inflammation, and New Onset Asthma

This study has been completed.
Sponsor:
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)
ClinicalTrials.gov Identifier:
NCT00241696
First received: October 17, 2005
Last updated: April 26, 2012
Last verified: April 2012
  Purpose

To examine air pollution, inflammation and new onset asthma in a large cohort of children in southern California.


Condition
Asthma
Lung Diseases

Study Type: Observational

Resource links provided by NLM:


Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Study Start Date: August 2005
Study Completion Date: June 2010
Detailed Description:

BACKGROUND:

Ambient air pollution is well accepted as a cause of asthma exacerbations, but its role in the etiology of new onset asthma is less clear. Evidence for an etiologic role of ambient air pollutants is emerging from epidemiologic studies; however, the ecologic patterns of increasing asthma prevalence concurrent with decreasing levels of some pollutants have raised questions about the validity of these associations. A better understanding of the biological processes that mediate the effects of ambient air pollution on asthma occurrence is likely to contribute to answering these questions. Chronic oxidative/nitrosative stress and airway inflammation are probably critical processes in asthma etiology and these inter-related processes may mediate the increased asthma risk from air pollution.

This study builds on the existing Asthma Incidence Risk (AIR) study which is an ongoing cohort study consisting of 6000 children with new onset asthma. The children live in 12 communities in Southern California. The communities were chosen to give a range of the key ambient air pollutants of ozone, small particulates, NOx, acid vapors and tailpipe emissions.

DESIGN NARRATIVE:

The study will use exhaled nitric oxide (eNO) to investigate the role of inflammation and oxidative/nitrosative stress in the pathobiology of new onset asthma, with a focus on ambient air pollution and genetic susceptibility. The investigators choose ambient pollutants based on potential contribution to oxidative/nitrosative stress (O3; particulates (PM10 and PM2.5 and their chemical constituents, particle counts, NOx (NO and NO2), acid vapors; and fresh tailpipe emissions). The primary hypotheses to be assessed in the program of research are: 1) children with high ambient air pollution exposures have chronic airway inflammation as indicated by elevated eNO. 2) susceptibility to airway inflammation and oxidative/nitrosative stress from ambient air pollution varies by NOS1, NOS2. NOS3. GSTM1. GSTP1. NQO1, and HO-1 haplotypes and functional variants, and 3) children with chronic airway inflammation as indicated by elevated eNO are at increased risk for new onset asthma. To test these hypotheses, the study builds on the population resource of the Asthma Incidence Risk (AIR) study, an ongoing prospective cohort study of the determinants of new onset asthma in 6000 children in 13 southern California communities, and an extensive program of ambient air pollution exposure characterization in these communities. The investigators will measure eNO using off-line techniques and genotype 3000 children from the AIR cohort. A number of resources will enhance the study, including the Children's Environmental Health Center, the Molecular Biology Core of Southern California Environmental Health Sciences Center, and expertise from the Southern California Particle Center and Supersite.

  Eligibility

Ages Eligible for Study:   8 Years to 12 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

No eligibility criteria

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00241696

Sponsors and Collaborators
Investigators
Investigator: Frank Gilliland University of Southern California
  More Information

No publications provided

ClinicalTrials.gov Identifier: NCT00241696     History of Changes
Other Study ID Numbers: 1308
Study First Received: October 17, 2005
Last Updated: April 26, 2012
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Asthma
Lung Diseases
Bronchial Diseases
Hypersensitivity
Hypersensitivity, Immediate
Immune System Diseases
Lung Diseases, Obstructive
Respiratory Hypersensitivity
Respiratory Tract Diseases

ClinicalTrials.gov processed this record on October 30, 2014