The Effect of Deep Inhalation on Mannitol Responsiveness

Sponsor

University of Saskatchewan (Other)

Overall Status

Completed

CT.gov ID

NCT03505489

Collaborator

(none)

Enrollment

Location

Arms

10.9

Actual Duration (Months)

2.4

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The study will assess how the inhalation technique used (deep inhalations versus tidal breathing) influences the results of a mannitol challenge test and a methacholine challenge test, if at all.

Condition or Disease	Intervention/Treatment	Phase
Asthma	Procedure: Deep inhalation technique Procedure: Tidal breathing technique Drug: Methacholine Drug: Mannitol	Phase 3

Detailed Description

This study will look at airway responsiveness to inhaled methacholine and mannitol administered with and without deep inhalation. This study will also investigate the role of airway inflammation on these responses, using sputum differential cell counts and fractional exhaled nitric oxide.

This is a single center, open label, randomized study. Individuals with stable asthma will be eligible for enrollment. The study will consist of two parts, screening and testing.

Part 1: Screening

Participants will undergo consent procedures and assessments of fractional exhaled nitric oxide levels, airway responsiveness to methacholine and sputum induction. If participants show airway responsiveness to methacholine (i.e. methacholine PC20 16mg/mL), they will be scheduled to undergo the testing part of the study.

Part 2: Testing

Participants will be randomized to undergo two methacholine or two mannitol challenges. Further randomization will occur with respect to whether the standard challenge method or the modified challenge method is performed first.

Study Design

Study Type:

Interventional

Actual Enrollment :

26 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

None (Open Label)

Primary Purpose:

Other

Official Title:

The Effect of Deep Inhalation on Mannitol Responsiveness

Actual Study Start Date :

Jun 1, 2018

Actual Primary Completion Date :

Apr 30, 2019

Actual Study Completion Date :

Apr 30, 2019

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Mannitol challenge Mannitol challenge performed per standard mannitol challenge procedure with deep inhalation technique	Procedure: Deep inhalation technique Use of deep inhalations for administration of inhalant Drug: Mannitol Mannitol indirect bronchoconstrictor used for bronchoprovocation challenge Other Names: Aridol
Experimental: Mannitol challenge w/ TBI Mannitol challenge performed per standard mannitol challenge procedure except with tidal breathing technique	Procedure: Tidal breathing technique Use of tidal breathing for administration of inhalant Drug: Mannitol Mannitol indirect bronchoconstrictor used for bronchoprovocation challenge Other Names: Aridol
Experimental: Methacholine challenge w/ DI Methacholine challenge performed per standard 2-minute tidal breathing challenge procedure except with deep inhalation technique	Procedure: Deep inhalation technique Use of deep inhalations for administration of inhalant Drug: Methacholine Methacholine direct bronchoconstrictor used for bronchoprovocation challenge Other Names: Provocholine
Experimental: Methacholine challenge Methacholine challenge performed per standard 2-minute tidal breathing challenge procedure (tidal breathing technique)	Procedure: Tidal breathing technique Use of tidal breathing for administration of inhalant Drug: Methacholine Methacholine direct bronchoconstrictor used for bronchoprovocation challenge Other Names: Provocholine

Outcome Measures

Primary Outcome Measures

Effect of deep inhalation (versus tidal breathing) on mannitol provocative dose causing a 15% fall in forced expiratory volume in one second (FEV1) [24 hours between mannitol challenges]
Shift in mannitol provocative dose causing a 15% fall in forced expiratory volume

Secondary Outcome Measures

Effect of airway inflammation on methacholine and mannitol challenge results-fractional exhaled nitric oxide [up to 2 weeks, from baseline to end of study]
Collection of fractional exhaled nitric oxide at screening - analysis of resulting measurement indicative of degree of baseline airway inflammation
Effect of airway inflammation on methacholine and mannitol challenge results-sputum [up to 2 weeks, from baseline to end of study]
Collection of sputum at screening - analysis for differential cell counts indicative of degree of baseline airway inflammation
Effect of deep inhalation (versus tidal breathing) on methacholine provocative [24 hours between methacholine challenges]
Shift in methacholine provocative dose causing a 20% fall in forced expiratory volume

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 75 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

signed informed consent
men and women between 18 and 75 years of age
FEV1 at first measurement of greater than or equal to 65% predicted
methacholine provocative concentration causing a 20% in FEV1 at screening that is less than or equal to 16mg/ml
generally good health
stable asthma