Characterisation of Asthma in Obese Subjects

February 20, 2012 updated by: Louis-Philippe Boulet, Laval University

Characterisation of Asthma in Obese Subjects. Relationships Between Asthma and Obesity, Potential Mechanisms by Which Obesity Can Contribute to Asthma and Modify Treatment Responses

Our hypothesis:

Obese subjects with a physician's made diagnosis of asthma have a poorer asthma control than asthmatics with normal weight, less variability of peak expiratory flows (PEF) and bronchodilator response,increased induced sputum and systemic markers of inflammation and an increased prevalence of atopy.

Obese subjects have an increased incidence of co-morbidities such as rhinosinusitis, gastroesophageal reflux and sleep apnea syndrome.

This study aims to determine if, in comparison with asthmatics with a normal weight, paired for age and sex, obese subjects with asthma (all not using anti-inflammatory agents) show:

  • A more uncontrolled asthma, increased health care use and poorer quality of life
  • A reduced response to bronchodilators and diurnal variability of expiratory flows
  • More marked airway inflammation and evidences of a systemic inflammatory response
  • An increased prevalence of co-morbidities which can influence the report of respiratory symptoms or the severity of the disease, such as esophageal reflux symptoms, upper airway disease (rhinitis) and sleep apnea syndrome or other sleep disorder.

Study Overview

Status

Completed

Conditions

Detailed Description

Questionnaires on respiratory symptoms, health care use, quality of life, medication and asthma control will be administered and a thoracic examination performed.

Spirometry and bronchodilator response, blood tests for inflammatory parameters, pH measurements in exhaled air condensate and sputum induction will be performed. Peak expiratory flows will be measured and recorded on a diary card during one week.

On the second visit, measures of lung volumes and a methacholine challenge will be performed.

Study Type

Observational

Enrollment (Actual)

44

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Quebec
      • Québec, Quebec, Canada, G1V 4G5
        • Centre de Recherche, Hôpital Laval

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Subjects wiil be selected from the Hospital asthma primary care clinic and from advertisements in newspapers. Their will be offered to participate to the study

Description

Inclusion Criteria:

  • aged 18 and over.
  • in good health apart from asthma or obesity as determined by history and physical examination (no other condition which could influence the proposed tests).
  • All will be non smokers or ex- smokers for more than six months with a smoking history of no more than 10 pack- years (i.e., one pack per day or its equivalent for 10 years.)
  • Subjects will have a physician's made diagnosis of asthma and have received a bronchodilator prescription in the last year.

Exclusion Criteria:

  • Use of asthma medications other than bronchodilators
  • Subjects who are, in the opinion of the investigator, mentally or legally
  • incapacitated thus preventing informed consent from being obtained.
  • Subjects having a co-existing illness that precludes them from the trial.
  • Pregnancy or lactation

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Obese asthmatics
Obese subjects with asthma (on inhaled bd only)
Non-obese asthmatics
Non-obese subjects with asthma(on inhaled bd only)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Airway response to methacholine
Time Frame: two weeks
two weeks

Secondary Outcome Measures

Outcome Measure
Time Frame
lung volumes
Time Frame: Two weeks
Two weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

August 1, 2005

Study Completion (Actual)

July 1, 2010

Study Registration Dates

First Submitted

September 18, 2007

First Submitted That Met QC Criteria

September 18, 2007

First Posted (Estimate)

September 20, 2007

Study Record Updates

Last Update Posted (Estimate)

February 22, 2012

Last Update Submitted That Met QC Criteria

February 20, 2012

Last Verified

February 1, 2012

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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