title: Controlling on-demand gastric acidity in obese subjects: a randomized, controlled trial comparing a single dose of 20 mg rabeprazole and 20 mg omeprazole.
abstract: BACKGROUND
  Obesity is associated with a risk of gastroesophageal reflux disease. The pharmacodynamic efficacy of proton pump inhibitors has not been specifically evaluated in obese subjects. The aim of this study was to compare the antisecretory response to a single oral dose of 20 mg rabeprazole, 20 mg omeprazole and placebo in obese subjects.
  
  
  METHODS
  Gastric pH was monitored for 24 hours on three separate occasions in eighteen H. pylori-negative, asymptomatic obese subjects. Subjects were given omeprazole, rabeprazole or placebo in a randomized order and in a double-blind fashion. The main analysis criterion was 24-h percent of time post dose with intragastric pH above 3; secondary criteria were percentage of time above pH 4, median pH, [H+] concentrations and nocturnal acid breakthrough (NAB). Results were analyzed using linear mixed models and Wilks test comparing variances.
  
  
  RESULTS
  24-h median [IQ] percentages of time with gastric pH above 3 and 4 were higher with rabeprazole than omeprazole (46 [37-55] vs. 30 [15-55] %, 9 [5-11] % for placebo) but the differences did not reach statistical significance (p = 0.11 and 0.24, respectively). Median acid concentrations were significantly lower with rabeprazole than with omeprazole and placebo (22 [14-53] vs. 54 [19-130] and 95 [73-170] mmoles/l, p < 0.01) for all periods. The number of NAB was significantly lower with rabeprazole than with omeprazole (median 1 [1,2] vs. 2 [1-3], p = 0.04). Variances of 24-h data (pH above 3 and 4, median pH, [H+] concentrations) were significantly lower with rabeprazole than with omeprazole (p < 0.0001).
  
  
  CONCLUSIONS
  In asymptomatic obese subjects the gastric antisecretory response to a single dose of rabeprazole and omeprazole was strong and not significantly different between drugs despite a significantly more homogeneous response with rabeprazole.
  
  
  BACKGROUND
  ClinicalTrial.gov: NCT01136317.
authors.forename: Kafia
authors.initials: K
authors.lastname: Belhocine
authors.forename: Fabienne
authors.initials: F
authors.lastname: Vavasseur
authors.forename: Christelle
authors.initials: C
authors.lastname: Volteau
authors.forename: Laurent
authors.initials: L
authors.lastname: Flet
authors.forename: Yann
authors.initials: Y
authors.lastname: Touchefeu
authors.affiliation: Institut des Maladies de l'Appareil Digestif - CHU Hôtel Dieu, 44093 Nantes Cedex, France. stanislas.bruleydesvarannes@chu-nantes.fr.
authors.forename: Stanislas
authors.initials: S
authors.lastname: Bruley des Varannes
mesh_terms: D000328:Adult; D004311:Double-Blind Method; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009765:Obesity; D009853:Omeprazole / Q000008:administration & dosage / Q000494:pharmacology*; D054328:Proton Pump Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D064750:Rabeprazole / Q000008:administration & dosage / Q000494:pharmacology*; D013270:Stomach / Q000187:drug effects*; D055815:Young Adult
chemical_list: D054328:Proton Pump Inhibitors; D064750:Rabeprazole; D009853:Omeprazole