BACKGROUND: The value of esophageal baseline impedance (BI) in assessing proximal reflux and laryngopharyngeal symptoms (LPS) is unclear.

METHODS: 208 patients with LPS underwent 24-hour combined hypopharyngeal-esophageal impedance-pH monitoring. Proximal/distal BI were obtained and a slope-and-intercept model of proximal BI contour was constructed.

RESULTS: Proximal BI correlated with proximal/pharyngeal reflux (r=-0.21, p<0.01) and reflux symptom index (r=-0.14, p=0.08). Proximal BI contour model incorporating both BI change (slope) and BI just below upper esophageal sphincter (intercept) outperformed models using individual BI measures in predicting proximal (AIC: 110 vs 251-253) or pharyngeal (AIC: 32 vs 141-148) reflux.

CONCLUSION: Proximal esophageal impedance contour predicts proximal reflux n patients with LPS.