Health Effects of Diesel Exhaust in Asthmatic Patients: A Real-World Study in a London Street

This study has been completed.
Sponsor:
Collaborator:
Health Effects Institute
Information provided by:
Imperial College London
ClinicalTrials.gov Identifier:
NCT00127062
First received: August 4, 2005
Last updated: August 19, 2005
Last verified: August 2005
  Purpose

Acute exposure to diesel exhaust under normal city conditions leads to a worsening of symptoms of asthma, with reduction in lung function in asthmatic nonsmoking adults, dependent on the exposure dose and on the background severity of asthma.

The worsening asthma is accompanied by increased oxidative stress and inflammation in the lungs.


Condition Intervention Phase
Asthma
Procedure: Exposure
Phase 3

Study Type: Observational
Study Design: Observational Model: Defined Population
Time Perspective: Longitudinal
Official Title: Health Effects of Diesel Exhaust in Asthmatic Patients: A Real-World Study in a London Street

Resource links provided by NLM:


Further study details as provided by Imperial College London:

Estimated Enrollment: 60
Study Start Date: May 2003
Estimated Study Completion Date: April 2005
Detailed Description:

The investigators will recruit 60 nonsmoking asthmatics of mild and of moderate severity. They will be exposed to Oxford St. or to Hyde Park for 2 hours each, at a walking pace. Real time exposure to PM2.5, carbon monoxide and nitrogen dioxide will be made each time. Health outcome measurements will be made before and after exposure to each street. Statistical analyses will be made to examine the effect of diesel exposure on changes in health outcome measures.

  Eligibility

Ages Eligible for Study:   18 Years to 45 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

Subjects will be selected according to the current severity of their asthma; thirty from Steps 1 and 2 and thirty from Step 3 of the World Health Organization (WHO) Global Initiative for Asthma (GINA) asthma guidelines. These will include mild and moderate asthmatic states. Depending on baseline FEV1, subjects will undergo either a methacholine bronchial hyperresponsiveness assessment or airways reversibility testing. Subjects with normal FEV1 (>80% predicted) or normal FEV1/FVC ratio will undergo methacholine challenge. Subjects with FEV1 <80% predicted will undergo airways reversibility testing. Subjects must have either a PC20 of less than 8mg/ml methacholine, or improvement in FEV1 of 12% or more, following inhalation of short acting β-agonist (salbutamol 200μg from metered dose inhaler [MDI]). Skin prick testing will be conducted for common allergens (house dust mite, grass pollen, aspergillus fumigatus and cat hair). The results will only be for descriptive purposes, not as subject inclusion/exclusion criteria. Subjects may be atopic or non-atopic (according to history and allergy testing).

  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00127062

Sponsors and Collaborators
Imperial College London
Health Effects Institute
Investigators
Principal Investigator: Paul Cullinan, MD Imperial College London
Study Director: Fan Chung, MD Imperial College London
Principal Investigator: Mark Nieuwenhuijsen, PhD Imperial College London
Principal Investigator: Jim Zhang, PhD Rutgers U & UMDNJ
  More Information

No publications provided

ClinicalTrials.gov Identifier: NCT00127062     History of Changes
Other Study ID Numbers: 03-194
Study First Received: August 4, 2005
Last Updated: August 19, 2005
Health Authority: United Kingdom: Research Ethics Committee

Keywords provided by Imperial College London:
Exposure to Oxford Street
Exposure to Hyde Park

ClinicalTrials.gov processed this record on September 18, 2014