title: Characteristics of symptomatic reflux episodes in patients with non-erosive reflux disease who have a positive symptom index on proton pump inhibitor therapy.
abstract: OBJECTIVE
  The reason that some reflux episodes evoke symptoms is poorly understood, therefore the aim of this study is to assess the determinants of reflux perception in patients with non-erosive reflux disease (NERD) on proton pump inhibitor (PPI) therapy.
  
  
  METHODS
  Ten NERD patients with persistent symptoms, despite double-dose PPI therapy, were included in this study. All patients had a positive symptom index (SI), which was determined by ambulatory 24-hour combined impedance-pH monitoring. Reflux episodes were identified and classified as acid, weakly acidic or weakly alkaline reflux and were considered symptomatic if patients recorded a symptom within 5 min after a reflux episode.
  
  
  RESULTS
  A total of 954 liquid reflux episodes were detected, including 135 (14.2%) acid, 782 (82.0%) weakly acidic, and 37 (3.9%) weakly alkaline. Overall, 59 (6.2%) reflux episodes were symptomatic and the majority (88.1%) of symptomatic reflux episodes were weakly acidic reflux. When reflux episodes were confined to the distal esophagus, there were very few reflux symptoms. Proximal reflux is significantly more likely to be associated with reflux symptoms, irrespective of the acidity of the refluxate or the duration of proximal reflux episodes.
  
  
  CONCLUSIONS
  In NERD patients who have a positive SI on double-dose PPI therapy, the high proximal extent of refluxate is a major factor associated with reflux perception.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Nippon Medical School, Tokyo 113-8603, Japan. k-iwa@nms.ac.jp
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Iwakiri
authors.forename: Hirohito
authors.initials: H
authors.lastname: Sano
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Kawami
authors.forename: Mariko
authors.initials: M
authors.lastname: Umezawa
authors.forename: Seiji
authors.initials: S
authors.lastname: Futagami
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hoshihara
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nomura
authors.forename: Masao
authors.initials: M
authors.lastname: Miyashita
authors.forename: Choitsu
authors.initials: C
authors.lastname: Sakamoto
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D006356:Heartburn / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010465:Perception; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D064750:Rabeprazole
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D054328:Proton Pump Inhibitors; D064750:Rabeprazole