title: The pattern of esophageal acid exposure in gastroesophageal reflux disease influences the severity of the disease.
abstract: OBJECTIVE
  There is an independent association between the different patterns of esophageal acid exposure in gastroesophageal reflux disease and the severity of the disease.
  
  
  METHODS
  Case-comparison study.
  
  
  METHODS
  Department of surgery at a university hospital.
  
  
  METHODS
  A group of 401 patients with increased esophageal acid exposure divided into 4 groups according to the pattern of reflux: postprandial (n = 41), upright (n = 74), supine (n = 129), and bipositional (n = 157).
  
  
  METHODS
  The prevalence of mucosal injury and the status of the lower esophageal sphincter and esophageal motility were assessed in each group.
  
  
  RESULTS
  The likelihood of having indicators of the severity of gastroesophageal reflux disease increases progressively from postprandial to upright, supine, and bipositional reflux.
  
  
  CONCLUSIONS
  The pattern of esophageal acid exposure in gastroesophageal reflux disease is an objective predictor of the severity of disease and could be used for therapeutic decisions.
authors.affiliation: Department of Surgery, University of Southern California School of Medicine, Los Angeles 90033-4612, USA.
authors.forename: G M
authors.initials: GM
authors.lastname: Campos
authors.forename: J H
authors.initials: JH
authors.lastname: Peters
authors.forename: T R
authors.initials: TR
authors.lastname: DeMeester
authors.forename: S
authors.initials: S
authors.lastname: Oberg
authors.forename: P F
authors.initials: PF
authors.lastname: Crookes
authors.forename: R J
authors.initials: RJ
authors.lastname: Mason
mesh_terms: D016022:Case-Control Studies; D004942:Esophagitis, Peptic / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology; D004947:Esophagus / Q000473:pathology / Q000503:physiopathology; D005260:Female; D005744:Gastric Acid; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006551:Hernia, Hiatal / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010528:Peristalsis; D011187:Posture; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index