Sensory-Mechanical Responses to Eucapneic Voluntary Hyperventilation and Mannitol

Launched by DR. DIANE LOUGHEED · Apr 4, 2017

Keywords

ClinConnect Summary

This clinical trial is studying how certain breathing techniques and a medication called Mannitol affect people with specific types of asthma-related coughs, particularly those with cough variant asthma (CVA) and those who cough due to a test called methacholine challenge. The researchers want to see how these treatments cause symptoms like shortness of breath, coughing, and changes in lung function in people with these conditions compared to healthy individuals without asthma or chronic cough.

To participate in this trial, you must be between 18 and 65 years old and have either CVA or a cough triggered by methacholine but with normal airway sensitivity. Healthy individuals within the same age range who have no history of asthma or chronic cough are also eligible. Participants can expect to undergo specific breathing challenges and tests to measure their lung responses. It's important to note that if you've had a recent asthma flare-up or have certain medical issues, you may not be able to join. Overall, this study aims to improve our understanding of how these treatments work for people with chronic coughs related to asthma.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• * Individuals aged 18-65 years of age with CVA and individuals with methacholine-induced cough but normal airway sensitivity. The following definitions will be used:
• • 1. CVA: chronic cough (≥8 weeks) is the sole or predominant symptom and positive methacholine challenge (PC20 ≤ 16 mg/mL) and history of cough responding to specific asthma treatment (such as inhaled steroid or 1 week trial of bronchodilator);
• • 2. Methacholine-induced cough but normal airway sensitivity: chronic cough (≥8 weeks) is the sole or predominant symptom and negative methacholine challenges (PC20 \> 16 mg/mL).
• • Individuals aged 18-65 years of age with no history of asthma or chronic cough.
• Exclusion Criteria:
• • an exacerbation necessitating a change in medication, emergency department visit or hospitalizations within the previous 4 weeks
• • inability to perform acceptable spirometry
• • medical contraindications to methacholine challenge testing
• • smoking history in excess of 10 pack years Note: Previous treatment with inhaled or systemic corticosteroids is not an exclusion criterion; medication use will be recorded and examined in the analysis.