Clinical Trial: The Efficacy of Capsaicin Sensitivity Testing in Patients With Irritable Larynx Syndrome

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Observational

Official Title: The Efficacy of Capsaicin Sensitivity Testing in Patients With Irritable Larynx Syndrome

Brief Summary:

Irritable larynx syndrome (ILS) is a hyperkinetic laryngeal dysfunction that is characterized by a persistent cough, voice changes, or breathing difficulties, which are often triggered by an irritant. Diagnosis of ILS is difficult and typically made via a thorough review of the clinical history and, occasionally, the patient's reaction to an odor-provocation test. Standard treatment for ILS is behavioural therapy with a speech language pathologist (SLP), which provides symptom improvement for most patients. However, currently, there are no objective measures of the upper airway hyper-responsiveness in this condition to assist in diagnosing and monitoring disease severity.

Since the cough is irritant-based, it is anticipated that patients with ILS will have a hypersensitivity to the irritant capsaicin. Capsaicin is the active component of chili peppers and is what makes them hot. The capsaicin cough challenge is a well recognized test that involves inhaling different concentrations of capsaicin solutions to determine a cough reflex sensitivity.

The purpose of this research study is to confirm that ILS patients have a hypersensitivity to capsaicin compared to healthy volunteers. If a hypersensitivity is observed in ILS patients, the second objective of this study will be to see if behavioural therapy improves the cough reflex sensitivity in this patient population.

Detailed Summary: The proposed study has two purposes; the first is to utilize capsaicin cough challenge to demonstrate an increased efferent receptor sensitivity level in ILS subjects as compared to a control group. The second is to determine if there is an objective change in capsaicin cough challenge results after behavioral therapy, and whether it correlates to the subjective improvement. Self-reporting measures include two validated cough quality of life (QoL) questionnaires collected at the same intervals as the capsaicin testing.
Sponsor: St. Michael's Hospital, Toronto

Current Primary Outcome: cough reflex sensitivity [ Time Frame: measured before and after behavioural therapy for ILS participants (approximately 5 month time frame); measured once for healthy volunteers ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: St. Michael's Hospital, Toronto

Dates:
Date Received: February 11, 2014
Date Started: August 2016
Date Completion: August 2017
Last Updated: August 9, 2016
Last Verified: July 2016