ATP and Capsaicin Cough Provocation Test in Chronic Cough and Bronchiectasis

Guangzhou Institute of Respiratory Disease

Status

Unknown

Conditions

Bronchiectasis

Chronic Cough

Treatments

Diagnostic Test: Adenosine Triphosphate

Diagnostic Test: capsaicin

Study type

Observational

Funder types

Other

Identifiers

NCT03638063

GuangzhouIRD01

Details and patient eligibility

About

This is a randomized, cross-over, single-blind trial. Eligible patients will be randomly assigned to undergo either capsaicin or adenosine triphosphate (ATP) cough provocation test, followed by a washout period of 2 to 14 days. Participants will be crossed-over to undergo another cough provocation test. Patient would be under observation in the out-patient clinics for ~2 hours following the cough provocation tests in case of severe adverse events.

Full description

This is a randomized, cross-over, single-blind trial. After verification of the entry criteria, eligible patients will be, based on the randomization codes, randomly assigned to undergo either capsaicin or ATP cough provocation test (the participants will inhale capasaicin or ATP incremental concentration to induce cough, meanwhile the number of coughs and adverse events will be recorded in each concentration during the first 30 seconds), followed by a washout period of 2 to 14 days (no major changes in the use of concomitant medications are allowed,especially the medcines which are not allowed before test ). Participants will be crossed-over to undergo another cough provocation test. Patient would be under observation in the out-patient clinics for ~2 hours following the cough provocation tests in case of severe adverse events. Twenty four hours after each test, a follow-up telephone visit will be scheduled for all patients to record any response which may be related to the test.

Enrollment

200 estimated patients

Sex

All

Ages

18 to 60 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

Out-patients of either gender, ex- or never-smokers, aged between 18 and 60 years
Cough symptoms lasting for more than 8 weeks
Remaining free of acute upper respiratory tract infection for at least 4 weeks
Agreed to participate in the trial and signed informed consent.

Exclusion criteria

Patients with serious systemic diseases (such as malignant tumors), bullae, severe uncontrolled asthma, and a history of major hemoptysis
Systemic antibiotic use (except for maintenance low-dose macrolides) within 4 weeks
Pregnancy or lactation
Any known history of sensitivity to ATP or capsaicin
Poor understanding of the test procedure
Diagnosed with cough variant asthma or Eosinophilic bronchitis