Acid and non-acid reflux in Japanese patients with non-erosive reflux disease with persistent reflux symptoms, despite taking a double-dose of proton pump inhibitor: a study using combined pH-impedance monitoring

Abstract

Combined multi-channel intra-luminal impedance and pH (Mll-pH) monitoring can detect gastro-esophageal reflux and identify acid and non-acid reflux (NAR) events. It can be used for patients with persistent symptoms who are having proton pump inhibitor (PPI) therapy. The aim of this study is to determine the frequency of acid reflux and NAR and to establish their relationship with persistent reflux symptoms in Japanese patients with non-erosive reflux disease (NERD) who are on a double-dose of PPI therapy. Thirteen patients with NERD, with persistent reflux symptoms, despite taking PPI at least twice daily, were included in this study. Twenty-four-hour combined Mll-pH monitoring was carried out on all patients and reflux episodes were detected by impedance channels, located at 3, 5, 7, 9, 15 and 17 cm above the lower esophageal sphincter (LES) and classified into acid reflux and NAR, based on pH data from 5 cm above the LES. A positive symptom index (SI) was declared, if at least half of the symptoms were preceded by reflux episodes within 5 min. A total of 916 liquid reflux episodes were detected, and a total of 171 symptoms were recorded. Eight (4.7%) of 171 symptoms were related to acid reflux, and 68 (39.8%) were related to NAR. Seven (53.8%) patients had a positive SI and in these seven patients, a total of 79 symptoms were recorded. 5 (6.3%) of the 79 symptoms were related to acid reflux and 44 (55.7%) were related to NAR. Persistent reflux symptoms, in SI-positive patients with NERD on double-dose PPI therapy, are more likely to be associated with primarily non-acid reflux.