Study of an Oropharyngeal Aerosolized pH Probe for Diagnosing Laryngopharyngeal Reflux (LPR)

Emory University

Status: Completed

Conditions: Laryngopharyngeal Reflux

Study type: Observational

Funder types: Other; Industry

Identifiers

NCT00321503

1345-2005

DX-1 for LPR (Other Identifier)

Details and patient eligibility

About

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.

Full 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.

Enrollment: 45 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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