Clinical trial NCT00321503: Study of an Oropharyngeal Aerosolized pH Probe for Diagnosing Laryngopharyngeal Reflux (LPR)
Official title: Diagnosis and Response to Treatment of Laryngopharyngeal Reflux Using an Oropharyngeal Aerosolized pH Probe
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Laryngopharyngeal Reflux
Keywords: acid reflux
LPR
gastroesophageal reflux
GERD
pH probe
proton pump inhibitor
PPI
Lead sponsor: Emory University
Sponsor class: OTHER
Collaborators: name: AstraZeneca
name: Respiratory Technology Corporation
First posted: 2006-05-03
Enrollment: 45
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Pos controls: Subjects visiting the Emory Clinic/Emory Voice center with LPR symptoms.

Neg controls: Random subjects in Atlanta without LPR symptoms. See other descriptions for more details.

Brief summary: This study is a test of how well a new FDA-approved device is for diagnosing a condition known as laryngopharyngeal reflux (LPR). The device, which measures pH of the air in the upper throat, will be compared to several other methods for diagnosing laryngopharyngeal reflux.

Detailed description: It is estimated that up to 50% of patients with voice disorders and 4-10% of patients seen in otolaryngology practice experience laryngopharyngeal reflux (LPR). LPR has been implicated in the pathogenesis of numerous laryngeal disorders, including subglottic stenosis, laryngeal carcinoma, laryngeal contact ulcers, laryngospasm, and vocal cord nodules. In the pediatric population, it has been associated with asthma, sinusitis, and otitis media. Common symptoms include chronic and intermittent hoarseness, vocal fatigue, globus pharyngeus, cough, postnasal drip, chronic throat clearing, and dysphagia.

Like gastroesophageal reflux disease (GERD), the etiology of LPR is linked to esophageal sphincter dysfunction. In GERD, the lower esophageal sphincter (LES) is involved, whereas in LPR, the pathology results from upper esophageal sphincter (UES) dysfunction. However, diagnosis of LPR is more challenging than that of GERD. The classic reflux-like symptoms of heartburn and regurgitation are often absent in LPR.

The most widely used diagnostic modality for LPR is symptomatic response to treatment, including twice daily proton pump inhibitor (PPI) or H2 blocker therapy for several months. However, the use of a therapeutic modality to make a diagnosis clearly carries disadvantages, including potentially unnecessary exposure to a drug's side effect profile and lengthy time to diagnosis. Another diagnostic instrument is the reflux symptom index (RSI), a validated nine-item questionnaire assessing LPR symptoms. However, LPR symptoms are fairly nonspecific, also appearing in autoimmune and behavior disorders. Lastly, a 24-hour triple-pH probe may be the best objective test diagnosing LPR. However, this method is poorly tolerated by patients and difficulty with ease of administration limits its routine use. To date, we have remained in search of a minimally invasive and specific test for LPR.

In this study, we will investigate the use of a newly developed oropharyngeal pH probe for detecting aerosolized acid as an accurate and minimally invasive diagnostic instrument for LPR. This device has previously been shown to correlate to lower esophageal, upper esophageal, and lower pharyngeal pH as measured by a 24-hour triple channel bifurcated pH probe \[ACG Poster session by Dr. G Wiener\]. The number of oropharyngeal aerosolized acid reflux events and acid exposure times will be compared to RSI before and after twice daily proton pump inhibitor therapy. In addition, the correlation between acid reflux events and acid exposure times as measured by the Dx probe will be more rigorously compared to that measured by a triple pH probe.

Eligibility criteria: INCLUSION CRITERIA:

Group 1 (negative control):

* RSI ≤ 13
* No history of voice or swallowing disorders
* No active voice or swallowing disorders
* No history of heartburn, regular indigestion, and no prior or current diagnosis of GERD

Groups 2 and 3 (experimental group):

* Clinical symptoms consistent with LPR as measured by an RSI \> 13.
* No other voice or swallowing pathology on clinical exam

EXCLUSION CRITERIA:

* Regular treatment with an H2 blocker or proton pump inhibitor (PPI)
* History of laryngeal/pharyngeal surgery
* Any planned treatment of the larynx/pharynx other than treatment for LPR
* Smoking

Primary outcomes:
Secondary outcomes:
Other outcomes:
Locations:
city: Atlanta
country: United States
facility: Emory Voice Center
state: Georgia
Study officials:
affiliation: Dept of Otolaryngology
name: Adam Klein, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Dept of Otolaryngology / Director of Emory Voice Center
name: Michael M Johns, MD
role: STUDY_CHAIR
affiliation: Dept of Surgery
name: Leena Khaitan, MD, MPH
role: PRINCIPAL_INVESTIGATOR
affiliation: Emory University
name: Justin S Golub, BA
role: STUDY_DIRECTOR
References:
citation: Belafsky PC, Postma GN, Koufman JA. Validity and reliability of the reflux symptom index (RSI). J Voice. 2002 Jun;16(2):274-7. doi: 10.1016/s0892-1997(02)00097-8.
citation: Merati AL, Lim HJ, Ulualp SO, Toohill RJ. Meta-analysis of upper probe measurements in normal subjects and patients with laryngopharyngeal reflux. Ann Otol Rhinol Laryngol. 2005 Mar;114(3):177-82. doi: 10.1177/000348940511400302.