title: Acid and non-acid reflux in patients refractory to proton pump inhibitor therapy: is gastroparesis a factor?
abstract: OBJECTIVE
  To determine whether an increased number and duration of non-acid reflux events as measured using the multichannel intraluminal impedance pH (MII-pH) is linked to gastroparesis (GP).
  
  
  METHODS
  A case control study was conducted in which 42 patients undergoing clinical evaluation for continued symptoms of gastroesophageal reflux disease (both typical and atypical symptoms) despite acid suppression therapy. MII-pH technology was used over 24 h to detect reflux episodes and record patients' symptoms. Parameters evaluated in patients with documented GP and controls without GP by scintigraphy included total, upright, and supine number of acid and non-acid reflux episodes (pH < 4 and pH > 4, respectively), the duration of acid and non-acid reflux in a 24-h period, and the number of reflux episodes lasting longer than 5 min.
  
  
  RESULTS
  No statistical difference was seen between the patients with GP and controls with respect to the total number or duration of acid reflux events, total number and duration of non-acid reflux events or the duration of longest reflux episodes. The number of non-acid reflux episodes with a pH > 7 was higher in subjects with GP than in controls. In addition, acid reflux episodes were more prolonged (lasting longer than 5 min) in the GP patients than in controls; however, these values did not reach statistical significance. Thirty-five patients had recorded symptoms during the 24 h study and of the 35 subjects, only 9% (n = 3) had a positive symptom association probability (SAP) for acid/non-acid reflux and 91% had a negative SAP.
  
  
  CONCLUSIONS
  The evaluation of patients with a documented history of GP did not show an association between GP and more frequent episodes of non-acid reflux based on MII-pH testing.
authors.affiliation: Anna Tavakkoli, Bisma A Sayed, Nicholas J Talley, Baharak Moshiree, Department of Medicine, Columbia University Medical Center, New York, NY 10019, United States.
authors.forename: Anna
authors.initials: A
authors.lastname: Tavakkoli
authors.forename: Bisma A
authors.initials: BA
authors.lastname: Sayed
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Talley
authors.forename: Baharak
authors.initials: B
authors.lastname: Moshiree
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D004351:Drug Resistance; D005260:Female; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D005769:Gastrointestinal Motility; D018589:Gastroparesis / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D012307:Risk Factors; D013997:Time Factors; D017211:Treatment Failure; D055815:Young Adult
chemical_list: D054328:Proton Pump Inhibitors
keywords: Acid gastroesophageal reflux; Functional bowel disorder; Gastroparesis; Multi-channel intraluminal impedance; Non-acid gastroesophageal reflux