title: Pathophysiological characteristics of the various forms of gastro-oesophageal reflux disease. Spectrum disease or distinct phenotypic presentations?
abstract: BACKGROUND
  The traditional approach to gastro-oesophageal reflux disease as a spectrum disease has recently been criticised and the distinct phenotypic presentations model has been proposed.
  
  
  OBJECTIVE
  To evaluate the main pathophysiological characteristics of various gastro-oesophageal reflux disease presentations.
  
  
  METHODS
  Oesophageal manometry and 24-h pH-monitoring were performed in a gastro-oesophageal reflux disease series collected in a 7-year period.
  
  
  RESULTS
  Four hundred and twenty-one subjects were studied. Mean total percentage acid reflux time was significantly higher in long-segment Barrett's oesophagus and in ulcerative oesophagitis than in all the other gastro-oesophageal reflux disease groups, whilst in short-segment Barrett's oesophagus results were quite similar to those found in non-erosive reflux disease and in erosive reflux disease. Patients with ulcerative oesophagitis and long-segment Barrett's oesophagus were older than all the other gastro-oesophageal reflux disease groups. The mean lower oesophageal sphincter pressure was significantly reduced in non-erosive reflux disease, erosive reflux disease, ulcerative oesophagitis, short-segment Barrett's oesophagus and long-segment Barrett's oesophagus as compared with functional heartburn and hypersensitive oesophagus and with controls.
  
  
  CONCLUSIONS
  In keeping with the spectrum model of gastro-oesophageal reflux disease, severity of acid reflux increases from non-erosive reflux disease through erosive reflux disease up to ulcerative oesophagitis and long-segment Barrett's oesophagus. Ulcerative oesophagitis and long-segment Barrett's oesophagus could represent an advanced step in the natural history of gastro-oesophageal reflux disease. Our results do not confirm the distinct phenotypic presentations hypothesis.
authors.affiliation: Internal Medicine and Gastroenterology Unit, New S. Agostino Hospital, Via Martignana 51, 41100 Modena, Italy. m.frazzoni@ausl.mo.it
authors.forename: M
authors.initials: M
authors.lastname: Frazzoni
authors.forename: M
authors.initials: M
authors.lastname: Manno
authors.forename: E
authors.initials: E
authors.lastname: De Micheli
authors.forename: V
authors.initials: V
authors.lastname: Savarino
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001471:Barrett Esophagus / Q000503:physiopathology; D016022:Case-Control Studies; D016099:Endoscopy, Gastrointestinal; D050782:Esophageal pH Monitoring; D004941:Esophagitis / Q000503:physiopathology; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000503:physiopathology*; D006356:Heartburn / Q000503:physiopathology; D006551:Hernia, Hiatal / Q000503:physiopathology; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D014456:Ulcer / Q000503:physiopathology