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Pathogenesis and Genetics of Environmental Asthma Ozone Study

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ClinicalTrials.gov Identifier: NCT00574158
Recruitment Status : Completed
First Posted : December 17, 2007
Last Update Posted : September 29, 2014
Information provided by (Responsible Party):

December 14, 2007
December 17, 2007
September 29, 2014
July 2005
November 2011   (Final data collection date for primary outcome measure)
Pathogenesis and genetics of environmental asthma ozone study [ Time Frame: acute and at 18 to 24 hour followup. ]
Phenotype physiologic responses to ambient level of ozone exposure.
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Complete list of historical versions of study NCT00574158 on ClinicalTrials.gov Archive Site
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Pathogenesis and Genetics of Environmental Asthma Ozone Study
Project 2: Genetic Regulation of Ozone Induced Inflammation in Humans.

The goals of the research are designed to accomplish genetic association studies of candidate genes in healthy normal individuals exposed to 0.2 ppm for 2.25 hours with intermittent exercise in order to search for associations between defined genotypes/haplotypes and 3 specific in vivo respiratory endpoints: a) change in FEV1 immediately after ozone exposure; b) change nonspecific bronchial reactivity as reflected in the change in methacholine PC20 FEV1 24 hours after ozone exposure ; and c) change in lung epithelial integrity as reflected in the Clearance Halftime of technetium 24 hours after ozone exposure. These studies have been carried forward to take place in 4 phases:

i) healthy individuals have been exposed to O3 using our standard exposure protocol; and we will increase the numbers of individuals available for study.

ii) perform genetic association studies for the endpoints of spirometry (FEV1, FVC, FEV1/FVC), PC20 FEV1 for methacholine, and epithelial integrity (Clearance Halftime) for 3 candidate O3 response genes taken from literature searches and/or previously characterized to demonstrate associations. These physiologic endpoints have been examined in terms of both a continuum of response, and discrete "responder" and "non-responder" endpoints.

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Observational Model: Cohort
Time Perspective: Prospective
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Retention:   Samples With DNA
plasma, and ebc collected.
Probability Sample
Healthy adults, 18-35 y of age, both genders.
  • Asthma
  • Inflammation
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*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
June 2012
November 2011   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Subjects with normal lung function values, and of normal body habitus (i.e., < BMI of 30);
  • Do not have a history of lung disease, and not taking any medications for lung disease or other clinical disorders, and no prior or current smoking history.

Exclusion Criteria:

  • Non-willingness to sign a consent form for participation.
Sexes Eligible for Study: All
18 Years to 35 Years   (Adult)
Contact information is only displayed when the study is recruiting subjects
United States
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Michael Foster, National Institute of Environmental Health Sciences (NIEHS)
National Institute of Environmental Health Sciences (NIEHS)
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Principal Investigator: W Michael Foster, PhD Duke University
National Institute of Environmental Health Sciences (NIEHS)
September 2014