title: Randomised clinical trial: low-volume bowel preparation for colonoscopy - a comparison between two different PEG-based formulations.
abstract: BACKGROUND
  Low-volume bowel preparations with polyethylene glycol (PEG) have been shown to provide an equivalent cleansing with improved tolerability as compared with standard PEG bowel preparation for colonoscopy. A new iso-osmotic sulphate-free formulation of PEG-Citrate-Simethicone (PEG-CS) in combination with bisacodyl has been recently developed.
  
  
  OBJECTIVE
  To compare the quality of bowel cleansing with PEG-CS with bisacodyl vs. PEG-Ascorbate (PEG-ASC) in adult out-patients undergoing colonoscopy.
  
  
  METHODS
  Randomised, observer-blind, parallel group study in adult out-patients undergoing colonoscopy in five Italian centres. Both preparations were taken the evening before the procedure. Subjects were instructed to take 2-4 tablets of 5 mg bisacodyl at 16:00 hours and 2 L of PEG-CS at 20:00 hours or 2 L of PEG-ASC plus 1 L of additional water the day before colonoscopy. Bowel cleansing was evaluated according to the Boston Bowel Preparation Scale (≥6 scores were considered as 'clinical success'), and mucosal visibility according to a 3-point scale. Tolerability, acceptability and compliance were also evaluated.
  
  
  RESULTS
  Four hundred and eight patients were randomly allocated to PEG-CS and bisacodyl (n = 204, male patient 48%, mean age 59.1 years) or PEG-ASC (n = 204, male patient 51%, age 59.4 years). In the planned per-protocol analysis, the rate of successful preparation was 79.1% following PEG-CS with bisacodyl, and 70% following PEG-ASC (P < 0.05). Mucosal visibility was evaluated as optimal in 56.1% in the PEG-CS and bisacodyl and 46.3% in the PEG-ASC group (P < 0.05). There were no serious adverse events (AE) in each of the two experimental groups. Two subjects in the PEG-ASC group discontinued the study because of AE.
  
  
  CONCLUSIONS
  Polyethylene glycol-Citrate-Simethicone in combination with bisacodyl was more effective for bowel cleansing than PEG-ASC for out-patient colonoscopy. Tolerability, safety, acceptability and compliance of the two low-volume bowel preparations were similar.
authors.affiliation: Digestive Endoscopy Unit, Istituto Clinico Humanitas, Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Repici
authors.forename: R
authors.initials: R
authors.lastname: Cestari
authors.forename: V
authors.initials: V
authors.lastname: Annese
authors.forename: G
authors.initials: G
authors.lastname: Biscaglia
authors.forename: E
authors.initials: E
authors.lastname: Vitetta
authors.forename: L
authors.initials: L
authors.lastname: Minelli
authors.forename: G
authors.initials: G
authors.lastname: Trallori
authors.forename: S
authors.initials: S
authors.lastname: Orselli
authors.forename: A
authors.initials: A
authors.lastname: Andriulli
authors.forename: C
authors.initials: C
authors.lastname: Hassan
mesh_terms: D000368:Aged; D001726:Bisacodyl / Q000008:administration & dosage*; D002400:Cathartics / Q000008:administration & dosage*; D019343:Citric Acid / Q000008:administration & dosage*; D003113:Colonoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D012841:Simethicone / Q000008:administration & dosage*; D007507:Therapeutic Irrigation / Q000379:methods; D016896:Treatment Outcome
chemical_list: D002400:Cathartics; D001726:Bisacodyl; D019343:Citric Acid; D011092:Polyethylene Glycols; D012841:Simethicone