Lactulose vs. Polyethylene Glycol as Bowel Preparation for Colonoscopy in Adults

Colonoscopy is the gold standard in bowel assessment when there is suspicion of colon and rectum pathology. Bowel cleansing is necessary to ensure an optimal visualization of colonic mucosa, allowing this form of detection and removal of polyps. Nowadays international recommendations have multiple bowel preparations. There are differences among them regarding adherence, tolerance and adverse effects. Lactulose (LAC) is widely used in treating constipation. However, there are some randomized clinical assays using LAC as bowel preparation with excellent results according to bowel preparation and tolerance scales. Adherence to bowel preparation significantly affects the result in the endoscopic study.

Safety of polyethylene glycol (PEG) formulations has been validated in several studies, it presents little severe side effects and the advantage of its applicability to patients with several comorbidities (heart, liver and kidney without water deprivation). However, its main disadvantage lies in the need to ingest large amounts of liquid (3-4L), generating intolerance thereto in 15%-45% of patients.

Bowel cleansing preparation with PEG is widely used in clinical practice. Considering that according to international studies reporting better tolerance and adherence with LAC; it is suggested to compare the level of bowel preparation, tolerance and adherence between two groups with LAC and PEG.

Study Overview

• Status: Completed
• Conditions: Colonoscopy; Bowel Preparation; Polyethylene Glycol; Lactulose; Bisacodyl
• Intervention / Treatment: Drug: Polyethylene Glycol 3350; Drug: Lactulose

• Study Type: Interventional
• Enrollment (Actual): 150
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Uruguay
  • Montevideo, Uruguay
    • Hospital de Clinicas

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

- Patients over 18 years with no bowel surgical procedures

Exclusion Criteria:

• Patients willingly deciding not to enter into the study
• Pregnant women
• Patient with colonic resections and/or ileostomies
• Inflammatory bowel disease
• Colonic optimization by prior colonoscopy with poor preparation
• Suspected intestinal occlusion or perforation, intussusception
• Patient with melenas
• Oral iron intake in the past 10 days
• Emergency colonoscopy
• Hypersensitivity to any of the components comprised in preparations.
• Diabetics
• Chronic kidney disease in dialysis
• Uncorrected severe dystonias
• Severe psychiatric illness (schizophrenia)
• Low IQ to understand bowel preparation
• Severe constipation (< 1 weekly stool)
• Chronic diarrhea with high rate (≥ 4 daily evenly loose consistency stools for more than 4 weeks)
• Unbalanced heart diseases (ischemic cardiopathology, congestive heart failure, unstable angina, arrhythmias and untreatable high blood pressure)
• Ascites

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Lactulose group; Patients participating in the study shall go on with their usual diet prior to colonoscopy. Three days before avoid consuming fruits, vegetables, seeds and cereals. A low residue soft and liquid diet is allowed. The day before the study, the group receiving lactulose shall take 4 tablets of Bisacodyl (5 mg) the day before the study at 6pm. Then, at 8pm a bottle of 250 mL (162.5g lactulose) of lactulose shall be dissolved in 600 mL of water and all contents (850 mL) shall be taken in 2 hours. At 10pm they have to drink 2 liters still water.	Drug: Lactulose; 4 tablets of Bisacodyl (5 mg) + 250 mL (162.5g lactulose) of lactulose + 600 mL of water + 2 L of water; Other Names: Bisacodyl 20 mg; Water 600 mL
Experimental: Polyethylene glycol group; Patients participating in the study shall go on with their usual diet prior to colonoscopy. Three days before avoid consuming fruits, vegetables, seeds and cereals. A low residue soft and liquid diet is allowed. The day before the study, the group receiving polyethylene glycol (PEG) should take 4 tablets of Bisacodyl (5 mg) at 4pm. Then, at 6pm, 3 bottles of PEG (Polyethylene glycol 3350 60 g; sodium chloride 1.46 g; potassium chloride 745 mg; Sodium bicarbonate 1.68 g; anhydrous sodium sulfate 5.68 g; pineapple flavoring 483 mg) shall be dissolved in 3 liters of water (1 bottle per liter) and they shall take half the preparation, that is 1 liter and a half in 2 hours. At 10pm they shall take the remaining contents in 2 hours.	Drug: Polyethylene Glycol 3350; 4 tablets of Bisacodyl (5 mg) + 3 bottles Polyethylene Glycol 3350 (Polyethylene glycol 3350 60 g; sodium chloride 1.46 g; potassium chloride 745 mg; Sodium bicarbonate 1.68 g; anhydrous sodium sulfate 5.68 g; pineapple flavoring 483 mg) + 3 L of water; Other Names: Bisacodyl 20 mg; Water 3 L

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Compare lactulose vs. Polyethylene Glycol as bowel cleansing preparation for colonoscopy	Compare the level of bowel preparation (by Boston Bowel Preparation Scale) between two groups with lactulose and Polyethylene Glycol. The minimum and maximum value is 0 and 9, respectively. A proper preparation is consider a Boston Bowel Preparation Scale ≥ 2 scores in each colonic segment. Unsuitable preparation a Boston Bowel Preparation Scale < 2 scores in any of the segments. Score 0: is considered a segment of unprepared colon with mucosa that cannot be observed given the presence of solid stool which does not disappear after cleansing. Score 1: part of the colonic mucosa is observed; other areas cannot be suitably assessed given the presence of staining, residual matter and/or opaque liquid. Score 2: little remaining residual matter and small matter fragments which do not prevent correct visualization of colonic mucosa in said segment. Score 3: colonic mucosa which can be entirely observed with no residual matter nor small fragments of matter and opaque liquid.	6 months
Establish Boston Bowel Preparation Scale inter and intra-observer variability	Two researchers shall review the endoscopic study videos and they shall complete the Boston Bowel Preparation Scale inter-observer questionnaire. Results obtained by the endoscopist in charge of the study and the observers shall be compared so as to establish inter-observer variability. Researchers shall analyze one month later again all colonoscopies recorded thus establishing Boston Bowel Preparation Scale of each endoscopy. Then results previously established shall be compared so as to establish intra-observer variability. The minimum and maximum value is 0 and 9, respectively. A proper preparation is consider a Boston Bowel Preparation Scale ≥ 2 scores in each colonic segment. Unsuitable preparation a Boston Bowel Preparation Scale < 2 scores in any of the segments.	7 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assess tolerance between lactulose and Polyethylene Glycol.	To assess tolerance it will be considered: good tolerance those patients with 3 or less symptoms with no major criterion; regular tolerance those patients with 4-5 symptoms, without major criterion and bad tolerance those patients with 6 or more symptoms or 1 or more major criteria.	6 months
Assess adherence between lactulose and Polyethylene Glycol.	To assess adherence it shall be assessed if the preparation was completed as well as the will to repeat the same preparation in the future.	6 months
Assess side effects between lactulose and Polyethylene Glycol.	To assess side effects of both preparations that will be considered: nausea, vomiting, abdominal pain or bloating, sickness, lipothymia, palpitations, precordial pain, insomnia, anal pain or burning, dry mouth, tinnitus, unpleasant taste.	6 months
Establish colonoscopy global adenoma detection rate with lactulose and Polyethylene Glycol.	It correspond to the number of adenomas/adenocarcinomas (histological diagnosis) divided by the total number of colonoscopies performed times 100.	6 months
Establish colonoscopy cecal intubation rate in with lactulose and Polyethylene Glycol.	It correspond to the number colonoscopies visualizing ileocecal valve divided by the total number of colonoscopies performed times 100.	6 months

Collaborators and Investigators

• Sponsor: Hospital de Clínicas Dr. Manuel Quintela
• Investigators: Principal Investigator: IGNACIO MORATORIO, MD, Hospital de Clinicas; Principal Investigator: MARIA B RUSSO, MD, Hospital de Clinicas; Principal Investigator: FLORENCIA RODRIGUEZ, MD, Hospital de Clinicas

Study record dates

Study Major Dates

• Study Start (Actual): February 10, 2023
• Primary Completion (Actual): December 13, 2023
• Study Completion (Actual): December 13, 2023

Study Registration Dates

• First Submitted: January 18, 2023
• First Submitted That Met QC Criteria: February 10, 2023
• First Posted (Actual): February 13, 2023

Study Record Updates

• Last Update Posted (Actual): December 27, 2023
• Last Update Submitted That Met QC Criteria: December 24, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Gastrointestinal Agents; Cathartics; Laxatives; Lactulose; Bisacodyl; Polyethylene glycol 3350
• Other Study ID Numbers: 7477252

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Study protocol, Statistical Analysis Plan and Informed Consent Form
• IPD Sharing Time Frame: ENDED THE TRIAL
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No