Efficacy of Free Versus Low Residue Diet as Preparation for Screening Colonoscopy

NCT04664543 | Terminated

• 1 other identifier: 2019307
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

One tricky aspect of the recommendations for colonoscopy prep is diet. This has a significant impact on the experience of the patient or participant in the screening program and, on the other hand, low adherence has been found in some studies despite a potential Hawthorne effect . It is noteworthy that despite its impact on patient experience, it is an area for which little evidence is available, which is why the guidelines give low-quality recommendations and there is probably considerable variability in clinical practice . In the early days of colonoscopy, a liquid diet for 48 hours was mainly recommended, although some centers indicated a low-residue diet or even the commercially available NASA astronaut diet. Later, the indication for a liquid diet was consolidated until finally numerous studies were published in favor of a low-residue diet, managing to increase tolerance and the quality of the preparation . A limitation of the preparation studies must be borne in mind that the colon cleansing rating scales were not introduced until 1999 when the Aronchick scale was published. Although there is solid evidence in favor of a low-residue diet versus a liquid diet, the investigators do not have evidence on how many days of a low-residue diet should be recommended, and this is reflected in the ESGE (European Society of Gastrointestinal Endoscopy) and ASGE (American Society of Gastrointestinal Endoscopy) guidelines . A randomized clinical trial comparing 3 days versus 1 day of a low residue diet has recently been published . There were no statistically significant differences in the rate of adequate preparations (82.7% vs. 85.6% OR 1.2 95% IC 0.72 to 2.15). However, this study has limited statistical power and a design that allows a non-inferiority analysis has not been followed. In relation to this, our research group is finalizing a non-inferiority clinical trial in whose intermediate analysis, with 421 participants, the non-inferiority of 1 day of diet is fulfilled (rate of poor preparation in 1 day 0.95% vs. 4.74% in 3 days; d + 5%, difference -3.78% IC -6.88% to -1.12%) (38). It is likely, taking into account the available evidence and its evolution, that diet plays a secondary role in preparation. Although no studies designed to directly assess this have been conducted, the research group has indirect data. Walter et al, under the hypothesis that the impact of the fractional preparation and the new preparations on the preparation diminished the importance of the diet, conducted a non-inferiority clinical trial between 2012 and 2013 in which they randomized the patients to follow a diet liquid versus low residue for one day and fractional preparation with Moviprep (39). They established a non-inferiority margin of -13.5%. Their results show a rate of good preparation (Boston\> 5) in 68/72 (94.4%) in a liquid diet compared to 60/68 (88.2%) in a low-residue diet (p = 0.04) with a difference of -5.08% demonstrating non-inferiority of the low residue diet.

Conditions

Colorectal Cancer; Colon Polyp; Colon Adenoma

Keywords

colonoscopy; bowel cleansing; low fiber diet; colonoscopy preparation

Outcome Measures

Primary Outcomes (1)

• Adequate bowel cleansing

  Bowel cleansing has a rating using the Boston Bowel Preparation Scale above 1 in each segment . This score ranges fron 0 to 3 in each one of the three segments. Zero is the worst outcome and 3 is the best cleansing

  During colonoscopy (At the withdrawal phase)

Secondary Outcomes (9)

• Diet tolerability

  The day of the colonoscopy just before beginning

• Preparation tolerability

  The day of the colonoscopy just before beginning

• Adenoma detection

  adenoma detection is done during the colonoscopy but assesment will be done at the end of the study with the histology reports

• Polyp detection

  During colonoscopy

• Ceacal intubation time

  During colonoscopy

Study Arms (2)

3 days of low residue diet

ACTIVE COMPARATOR

Currently participants in the colorectal cancer screening program follow a 3 days low residue diet before colonoscopy. This is the active comparator arm of this study.

Other: Three days low residue diet

Free diet

EXPERIMENTAL

Participants assigned to this arm are NOT instructed to follow any kind of restriction in the diet before colonoscopy.

Other: Free diet

Interventions

Free diet OTHER

To follow the regular dietary habits with no restriction nor modification.

Also known as: Liberal diet, habitual diet

Free diet

Three days low residue diet OTHER

To follow the three days before colonoscopy a diet with low content in fiber or residues.

Also known as: low fiber diet

3 days of low residue diet

Eligibility Criteria

• Age: 50 Years - 69 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Men and women between 50 and 69 years old.
• Participants in the Program for the Early Detection of Colorectal Cancer with a positive result in the test for detecting occult blood in feces
• That they accept a colonoscopy and that they agree to participate in the study.

You may not qualify if:

• Contraindication to performing a colonoscopy.
• Severe renal insufficiency (\<30 ml / min).
• Known hypersensitivity or allergy to polyethylene glycol, ascorbic acid or sulfate.
• Known glucose-6-phosphate dehydrogenase deficiency.
• Known phenylketonuria.
• Known dyselectrolytemia: hyper / hyponatremia, hyperphosphatemia, hypermagnesemia, hyper / hypokalemia, hypocalcemia.
• Gastric emptying disorders: Known gastroparesis.
• Known hypoalbuminemia less than 3.4 g / dl.
• Crohn's disease or known ulcerative colitis.
• Participants with difficult-to-control hypertension (SBP\> 170mmHg or TAD\> 100mmHg) or NYHA grade III or IV heart failure.
• Ascites of any etiology
• People with cognitive impairment or mental illness that makes it difficult to adhere to instructions.
• People who do not understand Catalan or Spanish.

Sponsors & Collaborators

• Parc Taulí Hospital Universitari: lead
• Consorci Sanitari de Terrassa: collaborator
• Hospital Mutua de Terrassa: collaborator

Study Sites (1)

Hospital Universitari Parc Taulí

Sabadell, Barcelona, 08208, Spain

Location

Related Publications (1)

• Machlab Mashlab S, Martinez-Bauer E, Lopez P, Pujals MDM, Fernandez-Banares F, Selva A, Calvet X, Campo R. Unrestricted vs three-day low-residue diet for colonoscopy preparation. Results of a feasibility randomized trial. Rev Esp Enferm Dig. 2025 Jun;117(6):349-350. doi: 10.17235/reed.2024.10417/2024.

  PMID: 38591600 DERIVED

MeSH Terms

Conditions

Colorectal Neoplasms; Colonic Polyps

Condition Hierarchy (Ancestors)

Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Intestinal Diseases; Rectal Diseases; Intestinal Polyps; Polyps; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms

Study Officials

• Eva Martínez, PhD

  Hospital Universitari Parc Taulí

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: December 6, 2020
• First Posted: December 11, 2020
• Study Start: December 1, 2019
• Primary Completion: December 30, 2020
• Study Completion: December 30, 2020
• Last Updated: January 26, 2021

Record last verified: 2021-01

Locations

ES (1)