title: [The characteristics of esophagogastric junction contractile index in patients with gastroesophageal reflux disease or functional heartburn].
abstract: OBJECTIVE
  To study the role of esophagogastric junction contractile index (EGJ-CI) in evaluating the function of anti-reflux barrier, and in differentiating patients with gastroesophageal reflux disease (GERD) from those with functional heartburn (FH).
  
  
  METHODS
  A total of 115 patients presenting heartburn were enrolled in the study from January 2012 to June 2015.All subjects had completed Gerd-Q questionnaire and undergone gastroscopy, 24-hour pH-impedance monitoring and esophageal high-resolution manometry. GERD patients were divided into as reflux esophagitis, acid-nonerosive reflux disease (NERD) and weakly acid-NERD groups. Patients with normal esophageal mucosa, normal acid exposure and negative proton pump inhibitor test were enrolled in FH group. EGJ-CI (mmHg·cm) as well as EGJ rest pressure and 4s integrated relaxation pressure (IRP 4s) were measured.
  
  
  RESULTS
  Among the 115 patients, 18 were reflux esophagitis [(49.0±18.9) years, M∶F=10∶8], 25 were acid-NERD [(48.7±14.4) years, M∶F=13∶12], 37 were weakly acid-NERD [(52.0±14.8) years, M∶F=15∶22] and 35 were FH [(53.6±14.8), M∶F=8∶27]. No differences of Gerd-Q scores were noticed between the four groups. (1)Negative correlations were demonstrated between EGJ-CI and esophageal acid exposure time (r=-0.283, P=0.002), EGJ-CI and acid reflux events (r=-0.233, P=0.012), EGJ-CI and weakly acid reflux events (r=-0.213, P=0.022), EGJ-CI and non-acid reflux events (r=-0.200, P=0.032). (2)The value of EGJ-CI was significantly higher in FH patients than in the three subgroups of GERD(all P<0.01). EGJ rest pressure of FH group was higher than that of acid-NERD (P<0.01). IRP 4s in acid-NERD group was lower than that of FH and weakly acid-NERD (P<0.05). (3)The area under curve (AUC) of EGJ-CI was higher than that of EGJ-CIT, EGJ rest pressure or IRP 4s(0.686 vs 0.678, 0.641 and 0.578). The cut-off value of EGJ-CI to differentiate GERD from FH was 9.74 mmHg·cm with sensitivity 82.86% and specificity 51.52%.
  
  
  CONCLUSIONS
  The EGJ-CI values are negatively correlated with esophageal acid exposure time, weakly acid reflux events and non-acid reflux events. Thus it might be used as a metric to reflect the anti-reflux function of EGJ. According to the cut-off value of EGJ-CI 9.74 mmHg·cm, patients with GERD can be sensitively differentiated from patients with FH.
authors.affiliation: Department of Gastroenterology, Peking University Third Hospital, Beijing 100191, China.
authors.forename: K
authors.initials: K
authors.lastname: Wang
authors.forename: L P
authors.initials: LP
authors.lastname: Duan
authors.forename: Y
authors.initials: Y
authors.lastname: Ge
authors.forename: Z W
authors.initials: ZW
authors.lastname: Xia
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Xu
mesh_terms: D004943:Esophagogastric Junction / Q000503:physiopathology*; D004947:Esophagus / Q000503:physiopathology*; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D005773:Gastroscopy; D006356:Heartburn; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008365:Manometry; D009119:Muscle Contraction / Q000502:physiology*; D054328:Proton Pump Inhibitors; D011795:Surveys and Questionnaires
chemical_list: D054328:Proton Pump Inhibitors