Text Size

Neurophysiology of Cough Reflex Hypersensitivity

The recruitment status of this study is unknown because the information has not been verified recently.
Verified September 2009 by University of Manchester.
Recruitment status was  Not yet recruiting
Sponsor:
Collaborators:
Moulton Charitable Trust
Medical Research Council (MRC)
Information provided by:
University of Manchester
ClinicalTrials.gov Identifier:
NCT00977366
First received: September 14, 2009
Last updated: NA
Last verified: September 2009
History: No changes posted
  Purpose

Central sensitisation is an increase in the excitability of nerves within the central nervous system, which can lead to heightened sensitivity to certain stimuli. This process is involved in some chronic pain conditions e.g. migraines and non−cardiac chest pain. Recent work by our group suggests central sensitisation may be an important mechanism leading to chronic cough.

The main questions in this study include:

  1. Can the investigators induce temporary central sensitisation of the cough reflex in healthy volunteers for testing of new medications?
  2. Can the investigators demonstrate exaggerated sensitisation in patients with chronic cough (indicating these patients are already centrally sensitised)?

In animal studies, acid infusion into the gullet (oesophagus) is able to induce central sensitisation of the cough reflex. Acid infusion into the oesophagus has also been shown to induce central sensitisation in human healthy volunteers, increasing the sensitivity to pain on the front of the chest but this study did not test the the cough reflex. Using human participants, the investigators plan to test whether acid infusion into the oesophagus increases the sensitivity of the cough reflex in healthy volunteers and also patients complaining of chronic cough.


Condition Intervention
Chronic Cough
 Other: Hydrochloric acid 0.15 molar
Other: Saline

Study Type: Interventional
Official Title: Pilot Study Investigating Central Sensitisation of the Cough Reflex in Subjects With Chronic Cough and Healthy Volunteers

Resource links provided by NLM:

U.S. FDA Resources

Further study details as provided by University of Manchester:

Primary Outcome Measures:
  • Effect of oesophageal acid infusion on cough reflex sensitivity in chronic cough patients compared to healthy controls.

Intervention Details:
    Other: Hydrochloric acid 0.15 molar
    HCl will be infused in to the lower oesophagus through a distal infusion port located at the tip of an oesophageal stimulation catheter.
    Other: Saline
    Normal saline will be infused in to the lower oesophagus through a distal infusion port located at the tip of an oesophageal stimulation catheter.
  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

Healthy volunteers inclusion:

  • Over 18 years
  • Measurable cough reflex sensitivity − required as is the primary end−point
  • No current or past history of chronic cough or chronic respiratory disease

Chronic Cough Patients inclusion:

  • Over 18 years
  • Chronic persistent cough (> 8 weeks) despite investigation and/or treatment trials for cough variant asthma/post−nasal drip and gastro−oesophageal reflux
  • Normal chest radiograph − primary respiratory cause for cough excluded
  • Normal lung function − primary respiratory cause for cough excluded Measurable cough reflex sensitivity − required as primary end−point

Exclusion Criteria:

  • Recent upper respiratory tract infection (<4 weeks) − this can lead to increased sensitivity of the cough reflex which resolves as the infection settles
  • Pregnancy/breast−feeding − unknown effects of oesophageal acid infusion
  • Current smokers or ex−smokers with < 6 month abstinence or history > 20 pack years − smoking can alter the sensitivity of the cough reflex
  • Opiate or ACE inhibitor use or centrally acting medication − can alter the cough reflex sensitivity
  • Symptomatic gastro−oesophageal reflux, post−nasal drip or asthma (chronic cough cohort may have been treated for these in the past but cough did not resolve) − these conditions are known to cause cough and alter cough reflex sensitivity
  • Significant ongoing chronic respiratory/cardiovascular/gastro−intestinal/haematological/ neurological/psychiatric illness. We are aiming to recruit healthy volunteers and chronic cough patients who are otherwise healthy
  Contacts and Locations
No Contacts or Locations Provided
  More Information

No publications provided

Responsible Party: Dr Andrew Maines, R & D Department, Education and Research Centre, South Manchester University Hospital NHS Trust
ClinicalTrials.gov Identifier: NCT00977366     History of Changes
Other Study ID Numbers: 09/H1004/21
Study First Received: September 14, 2009
Last Updated: September 14, 2009
Health Authority: United Kingdom: Research Ethics Committee

Additional relevant MeSH terms:
Cough
Hypersensitivity
Respiration Disorders
Respiratory Tract Diseases
 Signs and Symptoms, Respiratory
Signs and Symptoms
Immune System Diseases

ClinicalTrials.gov processed this record on May 16, 2013