title: Upper esophageal sphincter and gastroesophageal junction pressure changes act to prevent gastroesophageal and esophagopharyngeal reflux during apneic episodes in patients with obstructive sleep apnea.
abstract: BACKGROUND
  Gastroesophageal reflux (GER) is thought to be induced by decreasing intraesophageal pressure during obstructive sleep apnea (OSA). However, pressure changes in the upper esophageal sphincter (UES) and gastroesophageal junction (GEJ) pressure during OSA events have not been measured. The aim of this study was to determine UES and GEJ pressure change during OSA and characterize the GER and esophagopharyngeal reflux (EPR) events during sleep.
  
  
  METHODS
  We studied 15 controls, nine patients with GER disease (GERD) and without OSA, six patients with OSA and without GERD, and 11 patients with both OSA and GERD for 6 to 8 h postprandially during sleep. We concurrently recorded the following: (1) UES, GEJ, esophageal body (ESO), and gastric pressures by high-resolution manometry; (2) pharyngeal and esophageal reflux events by impedance and pH recordings; and (3) sleep stages and respiratory events using polysomnography. End-inspiration UES, GEJ, ESO, and gastric pressures over intervals of OSA were averaged in patients with OSA and compared with average values for randomly selected 10-s intervals during sleep in controls and patients with GERD.
  
  
  RESULTS
  ESO pressures decreased during OSA events. However, end-inspiratory UES and GEJ pressures progressively increased during OSA, and at the end of OSA events were significantly higher than at the beginning (P < .01). The prevalence of GER and EPR events during sleep in patients with OSA and GERD did not differ from those in controls, patients with GERD and without OSA, and patients with OSA and without GERD.
  
  
  CONCLUSIONS
  Despite a decrease in ESO pressure during OSA events, compensatory changes in UES and GEJ pressures prevent reflux.
authors.affiliation: Division of Gastroenterology and Hepatology, Medical College of Wisconsin, 9200 W Wisconsin Ave, Milwaukee, WI 53226, USA.
authors.forename: Shiko
authors.initials: S
authors.lastname: Kuribayashi
authors.forename: Benson T
authors.initials: BT
authors.lastname: Massey
authors.forename: Muhammad
authors.initials: M
authors.lastname: Hafeezullah
authors.forename: Lilani
authors.initials: L
authors.lastname: Perera
authors.forename: Syed Q
authors.initials: SQ
authors.lastname: Hussaini
authors.forename: Linda
authors.initials: L
authors.lastname: Tatro
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Darling
authors.forename: Rose
authors.initials: R
authors.lastname: Franco
authors.forename: Reza
authors.initials: R
authors.lastname: Shaker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D049631:Esophageal Sphincter, Upper / Q000502:physiology*; D050782:Esophageal pH Monitoring; D004943:Esophagogastric Junction / Q000502:physiology*; D045853:Exhalation / Q000502:physiology; D005260:Female; D005764:Gastroesophageal Reflux / Q000503:physiopathology / Q000517:prevention & control*; D006801:Humans; D001239:Inhalation / Q000502:physiology; D057045:Laryngopharyngeal Reflux / Q000503:physiopathology / Q000517:prevention & control*; D008297:Male; D008365:Manometry; D008875:Middle Aged; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*; D055815:Young Adult