Introduction
Laryngopharyngeal reflux (LPR) is an inflammatory condition of the upper aerodigestive tract tissue related to direct and indirect effects of gastroduodenal content reflux, inducing morphological changes in the upper aerodigestive tract.1 LPR is evaluated based on laryngeal symptoms and findings. Empirical proton pump inhibitors (PPIs) along with lifestyle modifications are mainly used to treat patients with suspected LPR.1,2 However, some patients with suspected LPR do not experience remission of LPR symptoms despite long-term high-dose PPI therapy. This is because of various causes, such as patient compliance, lifestyle, and overdiagnosis of LPR.3
The 24-h multichannel intraluminal impedance (MII)-pH monitoring is most reliable to precisely detect the characteristics of reflux (acid vs. nonacid; gas vs. liquid) and diagnose LPR. Recent studies found that patients with suspected LPR refractory to PPI therapy did not exhibit abnormal findings in MII-pH monitoring.4,5 However, some patients with LPR with proximal all reflux episodes ≥1 in 24-h MII-pH monitoring are refractory to PPI therapy.6 It is unclear which patients with LPR might benefit from the PPI therapy. To the best of our knowledge, the association between response to PPI therapy and parameters of 24-h MII-pH monitoring in patients with LPR has not been studied.
This study aimed to (i) evaluate reflux characteristics in patients with LPR refractory to PPI therapy using 24-h MII-pH monitoring and (ii) identify parameters and associated values to predict the response to PPI therapy in such patients.