Combined pH-impedance monitoring and high-resolution manometry of Japanese patients treated with proton-pump inhibitors for persistent symptoms of non-erosive reflux disease

Abstract

Background: Data on acid and non-acid reflux patterns and esophageal function in Japanese patients with non-erosive reflux disease (NERD) are limited. The aim of this study was touse combined multichannel intraluminal impedance pH monitoring (MII-pH) and high-resolution manometry (HRM) to investigate the characteristics of Japanese patients who were treatedwith a "double-dose" (20 mg) of rabeprazol (a proton-pump inhibitor; PPI) for persistent symptoms of NERD. Methods: Twenty-five patients who complained of typical gastroesophagealreflux disease symptoms, which had occurred more than twice a week despite treatment withrabeprazol, were enrolled in the study. All patients underwent upper endoscopy, esophagealHRM, and 24-h MII-pH monitoring while double-dose PPI therapy was continued. Results:Twelve (48.0%) of the patients had a positive symptom index (SI) with 234 recorded symptoms,127 (54.3%) of which were related to reflux episodes. Of those with reflux episodes, 29 (22.8%)were related to acid reflux, while 98 (77.2%) were the result of a weaker acidic reflux. In acidreflux and in mixed (liquid-gas) reflux, the proximal esophageal region was involved to a significantly greater degree (P<0.002 and P=0.005, respectively) than the distal region. In liquidreflux, there was no difference between the distal and proximal regions. HRM showed thatproximal motility parameters were significantly more defective than in those of healthy volunteers. Conclusions: MII-pH monitoring indicated that weakly acidic reflux and mixed refluxatein the proximal esophagus is the major cause of persistent symptoms in patients with NERDwho are being treated with PPI. HRM showed that proximal esophageal dysfunction might bea key condition that facilitates reflux. © 2012 The Japan Society of Smooth Muscle Research.