Effect of Muscular Exercise on Cough Reflex (REFLEXE TOUX)

Central Hospital, Nancy, France

Status: Completed

Conditions: Cough

Treatments: Drug: Normal saline; Behavioral: Exercise; Drug: Capsaicin

Study type: Interventional

Funder types: Other

Identifiers

NCT02882555

2009-A00390-57

Details and patient eligibility

About

The hypothesis is that the cough reflex induced by capsaicin is inhibited during exercise. The purpose of this study is to determine if a short muscular exercise inhibits the cough reflex induced by capsaicin inhalation.

Full description

Cough is an important reflex of defense of airways. It is also one of the more frequent symptoms during respiratory diseases. Chronic cough can be a disabling condition, apparently idiopathic or associated to pathology such as asthma, sinusitis with posterior discharge or gastroesophageal reflux.

Factors susceptible to provoke or increase cough are well known, but inhibiting factors are much less known. Muscular exercise is thought to influence respiratory reflexes in a considerable and complicated way. For example, a bronchodilation is observed in healthy or asthmatic individuals, but recovery period frequently triggers asthma attacks. Effects of exercise on cough reflex are much less known.

This study aims to determine the influence of muscular exercise on cough reflex in children and healthy adults.

Highlighting the inhibition of cough reflex by exercise can have a significant effect on chronic cough patient care. There is actually no symptomatic treatment really effective without side effects.

Enrollment: 60 patients

Sex: All

Ages: 7 to 77 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Obtaining of informed consent (or informed consent of parents or persons with parental authority)
• Affiliation to social security
• Negative answer to all 12 questions of medical questionnaire for child or to all 11 questions of medical questionnaire for adult
• Normal cardio-respiratory examination
• Normal electrocardiogram
• Without spirometry obstructive syndrome (FEV1 > 70% of predicted value and FEV1/FVC >70%)

Exclusion criteria

• Refusal or impossibility of obtaining informed consent of person or of persons with parental authority)

Trial design

60 participants in 2 patient groups

Children

Experimental group

Description:

12 concentrations of caspaicin are administered: - 0.6, 1.2, 2.4, 4.8, 9.8, 19.5, 39, 78.1, 156.2, 312.5, 625, 1250 μmol/l. Capsaicin concentration eliciting at least 2 coughs (C2) or 5 coughs (C5) is determined. At least 1-hour-interval from capsaicin dose titration (in order to minimize tachyphylaxy) Administration of 4 inhalations at 1-min-interval: 2 C5 and 2 controls (normal saline) in random order at baseline At least 1-hour-interval (in order to minimize tachyphylaxy) Administration of 4 inhalations at 1-min-interval: 2 C5 and 2 controls in random order during exercise, when heart rate is maximum

Treatment:

Drug: Normal saline

Behavioral: Exercise

Drug: Capsaicin

Adults

Active Comparator group

Description:

As reference for more precise assessment of effects of development. 12 concentrations of caspaicin are administered: 0.49, 0.98, 1.95, 3.9, 7.8, 15.6, 31.3, 62.5, 125, 250, 500, 1000 μmol/l. Capsaicin concentration eliciting at least 2 coughs (C2) or 5 coughs (C5) is determined. At least 1-hour-interval from capsaicin dose titration (in order to minimize tachyphylaxy) Administration of 4 inhalations at 1-min-interval: 2 C5 and 2 controls (normal saline) in random order at baseline At least 1-hour-interval (in order to minimize tachyphylaxy) Administration of 4 inhalations at 1-min-interval: 2 C5 and 2 controls in random order during exercise, when heart rate is maximum

Treatment:

Drug: Normal saline

Behavioral: Exercise

Drug: Capsaicin