Cough challenge responses Respiratory
Conditions
Interventions
Current interventions as of 21/06/2024:
Participants will be asked to attend two visits. At the first visit, informed consent will be taken, followed by a screening visit to ensure study eligibility.
measurement of height and weight
and spirometry to measure the participants FEV1 and FVC. Upon confirmation of eligibility, the participant will be asked to complete either a capsaicin cough challenge or a citric acid cough challenge
and spirometry to measure the participants FEV1 and FVC. Upon confirmation of eligibility, the participant will be asked to complete a capsaicin cough challenge by inhaling doubling doses of capsaicin
Sponsors
University of Manchester
Eligibility
Sex/Gender
All
Age
18 Years to 100 Years
Inclusion criteria
Inclusion criteria: Current inclusion criteria as of 21/06/2024: 1. Aged =18 years 2. Normal spirometry (FEV1 and FVC %predicted of =80%) 3. No current or past history of chronic cough or any other respiratory disease 4. No current or history of chronic pain, irritable bowel syndrome, psychiatric illness or chronic headaches 5. No previous experience of performing cough challenges (capsaicin study arm only) 6. Must cough at least 2 times on a single inhalation of any dose of capsaicin/citric acid during the visit 1 cough challenge Previous inclusion criteria: 1. Aged =18 years 2. Normal spirometry (FEV1 and FVC %predicted of =80%) 3. No current or past history of chronic cough or any other respiratory disease 4. No current or history of chronic pain, irritable bowel syndrome, psychiatric illness or chronic headaches 5. No previous experience of performing cough challenges 6. Must cough at least 2 times on a single inhalation of any dose of capsaicin during the visit 1 cough challenge
Exclusion criteria
Exclusion criteria: Current exclusion criteria as of 21/06/2024: 1. Current smoker or ex-smoker with >20 pack-year history, and/or 20 pack-year history, and/or <6 months abstinence 2. Upper respiratory tract infection within the last 4 weeks 3. Use of ACE inhibitors 4. Use of anti-depressants 5. Use of centrally acting medications that may alter the cough reflex e.g. opiates 6. History of drug or alcohol abuse 7. Current pregnancy or breastfeeding 8. Concomitant conditions that may alter cough reflex sensitivity e.g. diabetes mellitus, Parkinson’s disease, cerebrovascular disease 9. Previous cough challenge experience
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Maximum cough response (Emax) is measured at visit 1 and visit 2 | — |
Secondary
| Measure | Time frame |
|---|---|
| Current secondary outcome measures as of 21/06/2024: 1. Capsaicin and citric acid concentrations evoking at least 50% of the Emax cough number (ED50) is measured at visit 1 and visit 2 2. Concentration of capsaicin evoking at least two coughs (C2) is measured at visit 1 and visit 2 3. Capsaicin and citric acid concentrations provoking at least five coughs (C5) is measured at visit 1 and visit 2 Previous secondary outcome measures: 1. Capsaicin concentrations evoking at least 50% of the Emax cough number (ED50) is measured at visit 1 and visit 2 2. Concentration of capsaicin evoking at least two coughs (C2) is measured at visit 1 and visit 2 3. Capsaicin concentrations provoking at least five coughs (C5) is measured at visit 1 and visit 2 | — |
Countries
England, United Kingdom
Contacts
Public ContactJoanne Mitchell
Outcome results
None listed