Methacholine Challenge: Comparison of Doubling and Quadrupling Methacholine Dose Regimes Using the Tidal Volume Method

Not Applicable

Completed

• Conditions: Asthma
• Interventions: Drug: Methacholine challenge

• Registration Number: NCT00890539
• Lead Sponsor: University of Saskatchewan

Brief Summary

The purpose of this study is to determine the difference (if any) in the result of the methacholine challenge (a test used by physicians in diagnosing asthma) when concentrations of methacholine are quadrupled versus doubled.

Detailed Description

The purpose of this study is to confirm that the tidal volume technique of methacholine delivery may be employed in methacholine challenges using a quadrupling dose schedule instead of the standard doubling dose schedule with similar diagnostic efficacy, with no increase in patient adverse events, and with a shorter investigational duration. This has previously been shown to be true using the dosimeter technique of methacholine challenge.

Study Timeline

• Study Start: 2009-02
• Primary Completion: 2009-03
• Study Completion: 2009-03
• Study First Submitted: 2009-03-02
• Study First Submitted QC: 2009-04-29
• Study First Posted: 2009-04-30
• Status Verified: 2009-11
• Last Update Submitted: 2009-11-23
• Last Update Posted: 2009-11-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 15

Inclusion Criteria

• You must be over 18 years of age; and
• You must have a diagnosis of asthma; and
• Excluding asthma, you are not aware of any other lung conditions or diseases.

Exclusion Criteria

• You have a known hypersensitivity (i.e. an overreaction of your immune system) to methacholine or other parasympathomimetic agents or cholinesterase inhibitors (i.e. agents that act in a similar way via your nervous system - to be discussed with study personnel); or
• You are a nursing mother or if you are a woman of child bearing potential who is, may be, or intends to become pregnant during testing as the effects of methacholine inhalation in these situations are not known; or
• Your baseline lung function is poor (ie. your FEV or forced expiratory volume in one second, is less than 65% of your predicted values). This will be performed and explained by study personnel prior to commencing methacholine inhalation testing; or
• You have had any respiratory infections for the last four weeks; or
• If you have allergies, and have been exposed to agents that trigger your asthma within the last four weeks; or
• If you have any significant chronic medical condition.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Quadrupling	Methacholine challenge	methacholine challenge using quadrupling concentrations
doubling	Methacholine challenge	doubling concentrations of methacholine

Primary Outcome Measures

Name	Time	Method
Methacholine PC20	1 week

Secondary Outcome Measures

Name	Time	Method
Subject measure of breathlessness - modified Borg scale	1 week

Trial Locations

Locations (1)

University of Saskatchewan; 🇨🇦 Saskatoon, Saskatchewan, Canada