title: Increased prandial air swallowing and postprandial gas-liquid reflux among patients refractory to proton pump inhibitor therapy.
abstract: OBJECTIVE
  Many patients with gastroesophageal reflux disease (GERD) have persistent reflux despite treatment with proton pump inhibitors (PPIs). Mixed gas-liquid reflux events are more likely to be perceived as symptomatic. We used esophageal impedance monitoring to investigate whether esophageal gas is processed differently among patients with GERD who do and do not respond to PPI therapy.
  
  
  METHODS
  We performed a prospective study of 44 patients with typical reflux symptoms with high levels of esophageal acid exposure during a 24-hour period; 18 patients were fully responsive, and 26 did not respond to PPI therapy. Twenty-four-hour pH impedance recordings were analyzed for fasting and prandial air swallows and reflux characteristics, including the presence of gas in the refluxate.
  
  
  RESULTS
  PPI-refractory patients had a higher number (83.1 ± 12.7 vs 47.8 ± 7.3, P < .05) and rate (10.5 ± 1.4 vs 5.9 ± 0.8/10 minutes, P < .05) of prandial air swallows than patients who responded to PPI therapy; they also had a higher number (25.5 ± 4.0 vs 16.8 ± 3.3, P < .05) and proportion (70% ± 0.03% vs 54% ± 0.06%, P < .05) of postprandial, mixed gas-liquid reflux. Symptoms of PPI-refractory patients were more often preceded by mixed gas-liquid reflux events than those of PPI responders. Fasting air swallowing and other reflux characteristics did not differ between patients who did and did not respond to PPIs.
  
  
  CONCLUSIONS
  Some patients with GERD who do not respond to PPI therapy swallow more air at mealtime than those who respond to PPIs and also have more reflux episodes that contain gas. These factors, combined with mucosal sensitization by previous exposure to acid, could affect perception of symptoms. These patients, who can be identified on standard 24-hour pH impedance monitoring, might be given behavioral therapy to reduce mealtime air swallowing.
authors: Gastrointestinal Unit 2, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Università degli Studi of Milan, Milan, Italy.
authors: Ivana
authors: I
authors: Bravi
authors: Philip
authors: P
authors: Woodland
authors: Ravinder S
authors: RS
authors: Gill
authors: Mohannad
authors: M
authors: Al-Zinaty
authors: Albert J
authors: AJ
authors: Bredenoord
authors: Daniel
authors: D
authors: Sifrim
mesh_terms: D000293:Adolescent; D000328:Adult; D000334:Aerophagy; D000368:Aged; D000818:Animals; D002648:Child; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D011446:Prospective Studies; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D054328:Proton Pump Inhibitors