Gastroesophageal Reflux and Chronic Cough

Abstract

Chronic cough could be caused by two distinct mechanisms; vagal reflexes via acid exposure to the distal esophagus (GERD) and direct exposure of gastric contents to the hypopharynx (LPR). The current GERD diagnostics using MII-pH monitoring and endoscopy focus primarily on pathophysiology on the distal esophagus, but not on the proximity of gastric contents. Patients with LPR may not have abnormal acid exposure to the distal esophagus or mucosal injury, and objective assessment on the proximity of gastric contents using hypopharyngeal multichannel intraluminal impedance (HMII) is therefore crucial to accurately evaluate LPRD-related chronic cough.