Randomized Clinical Trial to Evaluate the Colon Cleansing Quality of Polyethylene Glycol Compared With Polyethylene Glycol Plus Ascorbic Acid in Patients With Past Poor Colonic Preparation
Trial Snapshot
- Phase
- Phase 4
- Status
- Completed
- Sponsor
- Enrollment
- 472
- Locations
- 1
- Primary Endpoint
- Colon cleansing
Study Overview
Brief Summary
The purpose of the study is to assess whether a low volume polyethylene glycol (PEG) plus ascorbic acid based bowel preparation for colonoscopy is not inferior to a large volume polyethylene glycol preparation in subjects with past history of poor bowel preparation
Detailed Description
Two key quality indicators for colonoscopy are the cecal intubation rate and the percentage of neoplastic lesions detected. Both factors are associated with adequate bowel cleansing. Poor cleansing ranged from 5% to 30% across studies, negatively affecting the efficiency of colonoscopy.
The most important factor associated with poor colonic preparation is the past history of poor bowel preparation. However, there are no recommendations on the proper type of preparation in those patients. In two non-randomized studies inadequate cleansing in the second colonoscopy ranged from 9.8% to 23%. Randomized studies comparing high volume (3-4 liters) with low volume (2 liters) PEG preparations, which are better tolerated by patients, are therefore needed before making any recommendations in this regard.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Diagnostic
- Masking
- Single (Investigator)
Eligibility Criteria
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Age> 18 years
- •Outpatients with a history of past poor bowel prep, defined according to the Boston scale as a score less than
- •Signed informed consent
Exclusion Criteria
- •paralytic ileus, intestinal obstruction, megacolon, poorly controlled hypertension (systolic pressure> 180, dyastolic pressure> 100), congestive heart failure, acute liver failure, end stage renal disease (dialysis or pre-dialysis), New York Heart Association class III-IV, pregnancy, diagnosis of phenylketonuria, diagnosis of glucose-6-phosphate dehydrogenase deficiency, dementia. History of poor preparation in the previous colonoscopy, colon resection, less than 75% intake of the bowel preparation in the index colonoscopy, refusal to participate in the study, patients in whom a new colonoscopy is not indicated despite a poor bowel preparation(i.e. ileal Crohn disease with poor large bowel preparation), lack of compliance with the bowel preparation schedule.
Arms & Interventions
High volume
- Two 5 mg bisacodyl tablets It is a stimulant laxative with local action.
- Polyethylene glycol 4000: 16 envelopes (70 g of powder each). It includes electrolytes and sodium sulfate.
Intervention: Polyethylene glycol 4000 (Drug)
Low volume
- Two 5 mg bisacodyl tablets, taken in the same way as for the high volume group.
- Macrogol 3350 plus ascorbic acid: 4 envelopes, 2 containing 112 g polyethylene glycol and electrolytes and 2 with 2 g of ascorbic acid.
Intervention: Macrogol 3350 plus ascorbic acid (Drug)
Outcomes
Primary Outcomes
Colon cleansing
Time Frame: 30 days
Colon cleansing will be assessed just after colonoscopy by the endoscopist in charge of performing the examination and afterwards images were reviewed by a the staff of endoscopists for validation (30 days). For assessing colon cleansing a validated scale (Boston scale) will be used.
Secondary Outcomes
- Detection of colorectal neoplasia(14 months)
- Tolerance of bowel preparation(Tolerance will be assessed just before colonoscopy by a research assistant)
Investigators
Alberto Domínguez Rodríguez
MD,PhD
Fundación Canaria Rafael Clavijo para la Investigación Biomédica