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Serial Exhaled Breath pH Monitoring

Serial Exhaled Breath pH Monitoring

Status
UNKNOWN
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT00330603
Enrollment
99
Registered
2006-05-29
Start date
2006-04-30
Completion date
2011-12-31
Last updated
2011-03-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Gastroesophageal Reflux

Keywords

Cough, Gastroesophageal Reflux

Brief summary

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.

Detailed description

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.

Interventions

PROCEDURESerial exhaled breath collections

collect breath for 5 minutes on 8 occasions

Sponsors

University of Virginia
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
5 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Outpatient * 5 years of age and older * Cough lasting a minimum of 3 weeks * Has been prescribed a proton pump inhibitor as a single therapeutic and diagnostic effort to control the cough

Exclusion criteria

* Inability to perform serial exhaled breath condensate collections at home * Unwillingness to initiate proton pump inhibitor therapy as prescribed by physician * Other changes planned in therapy, such as initiating or discontinuing cough suppressant therapy, initiating or augmenting antibiotic therapy, initiating or augmenting anti-inflammatory therapy * Previous treatment of respiratory symptoms with proton pump inhibitor therapy * Current treatment with angiotensin converting enzyme inhibitor medication or H2 antagonists * Regular exposure to an environmental irritant

Design outcomes

Primary

MeasureTime frame
pH of cough samples1 month
change in Leicester Cough Questionnaire (LCQ) total score1 month

Secondary

MeasureTime frame
proton pump inhibitor dosing1 month

Countries

United States

Contacts

Primary ContactJohn Hunt, MD
jfh2m@virginia.edu434-243-9324

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026