Serial Exhaled Breath pH Monitoring
Recruitment status was: Recruiting
This study will seek to determine the amount of acids a person with a chronic cough that is suspected to be related to acid reflux breathes out after coughing. The study will also seek to determine if this measurement can predict the best treatment for the cough.
Subjects with a chronic cough which is suspected to be related to acid reflux for which their doctor has prescribed a proton pump inhibitor medication will be enrolled in this study.
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||Serial Exhaled Breath pH Monitoring|
- pH of cough samples [ Time Frame: 1 month ]
- change in Leicester Cough Questionnaire (LCQ) total score [ Time Frame: 1 month ]
- proton pump inhibitor dosing [ Time Frame: 1 month ]
|Study Start Date:||April 2006|
|Estimated Study Completion Date:||December 2011|
|Estimated Primary Completion Date:||December 2011 (Final data collection date for primary outcome measure)|
Procedure: Serial exhaled breath collections
Acid reflux has been considered to be a key contributor to cough, particularly in patients with obstructive lung diseases. However, diagnosis has relied upon either responsiveness to high dose twice daily administration of proton pump inhibitor therapy or by 24 hour esophageal pH probes. This study is designed to provide information for the development of a clinically useful diagnostic (exhaled breath condensate pH) to identify the contribution of acid reflux to cough.
Exhaled breath condensate (EBC) pH has been well documented to reflect airway acidification. Acid reflux to the level of the hypopharynx, which is a key common trigger of acid reflux induced cough, acidifies the airway sufficiently to be identified with EBC pH assays. The association of low EBC pH with an immediately preceding cough strongly suggests an association of the cough with an airway acid event, and even if the acidity is not prolonged, acid reflux becomes highly suspect.
This study will examine the ability of EBC pH measurements to prognose the likelihood of a positive response to acid blockade with proton pump inhibitor therapy in subjects with chronic cough.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00330603
|United States, Virginia|
|University of Virginia|
|Charlottesville, Virginia, United States, 22908|
|Principal Investigator:||John Hunt, MD||University of Virginia|