The Correlation Between Airway Inflammation and Loss of Deep Inhalation Bronchoprotection in Asthmatics

NCT00404677 · Status: COMPLETED · Phase: NA · Type: INTERVENTIONAL · Enrollment: 18

Last updated 2008-01-23

No results posted yet for this study

Summary

The loss of deep inhalation bronchoprotection in asthmatic individuals has been shown to be related to the degree of airway hyperresponsiveness, a hallmark of asthma. In several studies, asthmatic individuals with mild airway hyperresponsiveness (AHR) (methacholine PC20 \> 2 mg/mL) had a difference in methacholine PC20 with and without deep inhalations that averaged 1.8 doubling methacholine concentrations (p=0.0003). Conversely, asthmatic individuals with moderate to severe AHR (methacholine PC20 ≤ 2 mg/mL) had a non-significant difference in methacholine PC20 with and without deep inhalations (p=0.09). This loss of deep inhalation bronchoprotection is also now believed to play an important role in the pathogenesis of asthma. Airway inflammation is another of the key features of asthma and information on airway inflammation is increasingly being used in the diagnosis and treatment of asthma. The level of airway inflammation (as measured by fraction of exhaled nitric oxide and sputum eosinophilia) has also been shown to be correlated to the level of airway hyperresponsiveness (as measured by methacholine PC20). In addition, glucocorticoids have been shown to decrease airway hyperresponsiveness, further suggesting that these two phenomena, airway inflammation and airway hyperresponsiveness, are related. We therefore suggest that the degree of airway inflammation is related to the loss of deep inhalation bronchoprotection and expect there to be a negative correlation between the degree of deep inhalation bronchoprotection and airway inflammation.

Conditions

Interventions

OTHER

deep inhalation

deep inhalation is comprised of an inhalation manoeuver from FRC to TLC

Sponsors & Collaborators

  • University of Saskatchewan

    lead OTHER

Principal Investigators

  • Donald Cockcroft, MD, FRCP(C) · Department of Medicine, Division of Respirology, Critical Care and Sleep Medicine, University of Saskatchewan

Study Design

Allocation
RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Model
CROSSOVER

Eligibility

Min Age
18 Years
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2006-06-30
Primary Completion
2007-02-28
Completion
2007-02-28

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Entities

Diseases

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT00404677 on ClinicalTrials.gov