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Cough Reflex and Obstructive Sleep Apnea Syndrome

This study has been completed.
Information provided by:
Bichat Hospital Identifier:
First received: April 17, 2006
Last updated: April 21, 2006
Last verified: January 2004
Up to 70% of obese patients undergoing bariatric surgery have obstructive sleep apnea syndrome (OSAS). OSAS is responsible for laryngeal sensory impairment. As the afferent neural pathway involved in the initiation of cough is located in the laryngeal epithelium, cough reflex sensitivity may be decreased in obese OSAS patients. The researchers therefore conducted this study to determine the effect of OSAS associated with obesity on cough reflex sensitivity, assessed by cough reflex threshold to an inhaled irritant (citric acid).

Condition Intervention
Sleep Apnea Syndrome Procedure: Cough reflex test

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: Effect of Obstructive Sleep Apnea Syndrome Associated With Obesity on Cough Reflex Threshold to Citric Acid

Resource links provided by NLM:

Further study details as provided by Bichat Hospital:

Primary Outcome Measures:
  • To compare cough reflex threshold to citric acid between obese OSAS patients and obese non-OSAS patients

Secondary Outcome Measures:
  • To correlate OSAS severity assessed by apnea-hypopnea index and cough reflex threshold to citric acid

Estimated Enrollment: 40
Study Start Date: November 2001
Estimated Study Completion Date: February 2003
Detailed Description:
Obese patients undergoing scheduled bariatric surgery underwent a cough challenge as part of their routine preoperative evaluation. Patients were classified as presenting OSAS if apnea-hypopnea index obtained from preoperative full-night polysomnography was greater than 5/hour. Cough threshold was measured with citric acid. Increasing concentrations of mouth- nebulized citric acid (2.5, 5, 10, 20, 40, 80, 160, 320 and 640 mg/mL) were delivered during inspiration until a cough was elicited. The citric acid concentration eliciting one cough (C1) was defined as the cough reflex threshold.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Obese patient scheduled to undergo bariatric surgery

Exclusion Criteria:

  • Age less than 18
  • Active smoking
  • Psychotropic medication
  • Angiotensin-converting enzyme inhibitor or angiotensin II receptor antagonist medication
  • Pregnancy
  • Anesthesia or endotracheal intubation during the previous month
  • Allergic rhinitis
  • Upper airway or bronchopulmonary infection during the previous month
  • Chronic cough
  • Chronic respiratory disease
  • Pharyngolaryngeal disease
  • Neurological disease
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Please refer to this study by its identifier: NCT00317083

Anesthesiology Department, Bichat Hospital
Paris, France, 75018
Sponsors and Collaborators
Bichat Hospital
Principal Investigator: Jean Guglielminotti Anesthesiology Department, Bichat Hospital
  More Information

Publications: Identifier: NCT00317083     History of Changes
Other Study ID Numbers: JG-2006-BCH
Study First Received: April 17, 2006
Last Updated: April 21, 2006

Keywords provided by Bichat Hospital:
Cough Reflex
Citric acid
Sleep apnea syndrome

Additional relevant MeSH terms:
Sleep Apnea Syndromes
Sleep Apnea, Obstructive
Pathologic Processes
Respiration Disorders
Respiratory Tract Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms
Sleep Disorders, Intrinsic
Sleep Wake Disorders
Nervous System Diseases
Citric Acid
Calcium Chelating Agents
Chelating Agents
Sequestering Agents
Molecular Mechanisms of Pharmacological Action processed this record on September 21, 2017