Abnormal Pharyngeal pH Testing Predicts Response to Proton Pump Inhibitors in Patients with Chronic Cough and Laryngeal Complaints

Abstract

RATIONALE: Controversy exists as to the role of extra-esophageal reflux in the pathogenesis of chronic cough and laryngopharyngitis. One reason for this lack of consensus is the absence of a reliable diagnostic modality capable of determining which patients are likely to respond to anti-reflux measures. We sought to determine whether abnormal pharyngeal pH testing with the DxpH Measurement System is helpful for predicting which patients presenting with chronic cough and/or laryngeal complaints are likely to respond to acid suppression therapy. METHODS: Nineteen consecutive subjects presenting to an allergy department with cough and/or additional symptoms suspected to be of laryngeal origin and with abnormal pharyngeal pH testing were surveyed regarding symptom response and adherence to treatment with twice daily proton pump inhibitors. Self-reported symptom improvement scores from subjects reporting adherence to acid suppression therapy were compared to those of subjects reporting incomplete adherence to acid suppression therapy. RESULTS: The presenting symptoms included chronic cough, sensation of excessive throat mucus / post-nasal drip, throat clearing, globus, and hoarseness. Of those subjects with abnormal pharyngeal pH studies who took twice daily proton pump inhibitors as directed, 11 of 14 (78.6%) had >50% improvement in symptoms as compared to 1 of 5 subjects (20%) with abnormal pH studies who did not (P = 0.04). CONCLUSIONS: Pharyngeal pH testing with the DxpH Measurement System in patients presenting with symptoms of chronic cough and/or laryngopharyngitis is helpful in predicting response to acid suppression therapy.