title: Study of the influence of hiatus hernia on gastroesophageal reflux.
abstract: OBJECTIVE
  To explore whether the presence of a sliding hiatus hernia influences gastroesophageal reflux.
  
  
  METHODS
  Endoscopy and 24 h pH monitoring were performed for 197 outpatients with gastroesophageal reflux symptoms.
  
  
  RESULTS
  Of the 197 patients with symptoms of gastroesophageal reflux, patients with hiatus hernia accounted for 36%. The incidence of esophagitis in patients with hiatus hernia was significantly higher than that in patients without hiatus hernia. The results of 24 h pH monitoring showed that 84 patients had physiological reflux, 37 had pathological reflux without esophagitis, 64 had reflux esophagitis and 12 had physiological reflux concomitant with esophagitis. All the patients with hiatus hernia had a longer percentage time with supine reflux and a higher frequency of episodes lasting over 5 min at night compared to those without hiatus hernia. The incidence of combined daytime and nocturnal reflux in patients with hiatus hernia was significantly higher than that in patients without hiatus hernia.
  
  
  CONCLUSIONS
  Pathological reflux and reflux esophagitis in some patients with symptoms of gastroesophageal reflux represent two different stages of gastroesophageal reflux disease. Pathological reflux is the first stage, in which the lower esophageal sphincter is incompetent but the esophageal mucosal resistance effectively prevents regurgitated acid from damaging the esophageal mucosa. Reflux esophagitis represents the second stage, in which the aggression of the regurgitated acid is so strong that the esophageal mucosa fails to resist it and the epithelium of the esophagus is damaged. Patients with hiatus hernia have a high incidence of combined daytime and nocturnal reflux, with the latter being responsible for esophagitis.
authors.affiliation: Hui-Ming Zhu, Department of Gastroenterology, Shenzhen People's Hospital, Shenzhen 51 8001, Guangdong Province, China.
authors.forename: H M
authors.initials: HM
authors.lastname: Zhu
keywords: Endoscopy, gastrointestinal; Esophagitis, peptic; Gastroesophageal reflux; Hernia, hiatal; Hydrogen ion concentration