Physiology of Cough in Asthma: Comparison of Sensory-Mechanical Responses to Mannitol and Methacholine Challenge Tests

NCT ID: NCT01064245

Last Updated: 2022-02-28

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 29 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2010-02-01
• Study Completion Date: 2021-12-31

Brief Summary

Cough is a common, disruptive and at times disabling symptom which often prompts patients to seek medical attention. Determining the cause(s) of chronic cough can be challenging, and costly. Asthma and other airway disorders are among the most common causes of chronic cough; and cough can be the sole symptom of asthma. Little is known about why some patients with asthma primarily cough and do not develop the other symptoms of asthma such as shortness of breath or wheeze. Improved understanding of the reasons for these different manifestations may lead to new and more effective treatment strategies. We have notices differences in pressure measurements inside the chest in patients who mostly cough during induced bronchoconstriction, which might be part of the explanation for varying symptoms. This study will compare lung mechanical responses during methacholine and mannitol-induced induced airway narrowing between typical asthma, cough variant asthma (CVA) and an airway inflammatory disorder that is not asthma.The purpose of this research is to explore the pathophysiology and sensory-mechanics of cough in individuals with asthma, CVA and methacholine-induced cough but normal airway sensitivity using mannitol and high-dose methacholine bronchoprovocation testing.

Conditions

Asthma; Cough Variant Asthma

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Cough Variant Asthma

Those diagnosed with cough variant asthma.

Group Type: EXPERIMENTAL

high-dose methacholine challenge test

Intervention Type: DRUG

nebulized liquid inhalation, 0.0625 - 256 mg/mL, doubling doses

mannitol challenge test

Intervention Type: OTHER

inhaled powder, 0 - 635 mg, increments of 5,10, 20 and 40 mg

Asthma

Those with diagnosed asthma.

Group Type: EXPERIMENTAL

high-dose methacholine challenge test

Intervention Type: DRUG

nebulized liquid inhalation, 0.0625 - 256 mg/mL, doubling doses

mannitol challenge test

Intervention Type: OTHER

inhaled powder, 0 - 635 mg, increments of 5,10, 20 and 40 mg

Interventions

high-dose methacholine challenge test

nebulized liquid inhalation, 0.0625 - 256 mg/mL, doubling doses

Intervention Type: DRUG

mannitol challenge test

inhaled powder, 0 - 635 mg, increments of 5,10, 20 and 40 mg

Intervention Type: OTHER

Other Intervention Names

Provocholine; Aridol

Eligibility Criteria

Inclusion Criteria

1. Subjects with asthma or suspected CVA who have previously participated in or who have expressed interest in participating in studies will be invited to participate in the study. Previous treatment with inhaled or systemic corticosteroids is not an exclusion criterion, but medication use will be recorded and examined in the analysis.

Exclusion Criteria

1. An exacerbation necessitating any alteration in medication, emergency department visit or hospitalizations within the previous 4 weeks;

2. Inability to perform acceptable quality spirometry;

3. Medical contraindications to methacholine challenge testing 35, including:

1. Severe airflow limitation (FEV1 <50% predicted or <1.0 L);

2. Heart attack or stroke in last 3 months;

3. Uncontrolled hypertension, systolic BP > 200 or diastolic BP > 100;

4. Known aortic aneurysm;

5. Moderate airflow limitation < 60% predicted or <1.5 L);

6. Inability to perform acceptable quality spirometry;

7. Current use of cholinesterase inhibitor medication (for myasthenia gravis); and

8. Pregnant or nursing mothers.

4. Smoking history in excess of 10 pack years;

5. Medical contraindications to mannitol challenge testing, including:

1. Aortic or cerebral aneurysm;

2. Uncontrolled hypertension; and

3. Myocardial infarction or a cerebral vascular accident in the previous six months).

6. Women who are pregnant or breastfeeding because the effects of a possible hyperresponsiveness reaction to mannitol in mothers and/or fetuses are unknown and many compounds are excreted in human milk therefore caution should be taken.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

The Ontario Thoracic Society of the Ontario Lung Association

UNKNOWN

Sponsor Role: collaborator

Queen's University (William M Spear / Start Memorial Fund)

UNKNOWN

Sponsor Role: collaborator

Dr. Diane Lougheed

OTHER

Sponsor Role: lead

Responsible Party

Dr. Diane Lougheed

Professor of Medicine

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Diane Lougheed, MD

Role: PRINCIPAL_INVESTIGATOR

Queen's University

Scott Turcotte

Role: PRINCIPAL_INVESTIGATOR

Queen's University

Locations

Kingston General Hospital

Kingston, Ontario, Canada

Countries

Canada

Other Identifiers

2010-01

Identifier Type: -

Identifier Source: org_study_id