Increasing the low residue diet to 3 days does not improve the bowel cleansing in hard to prepare patients: Post hoc analysis of a randomized controlled trial

Gastroenterol Hepatol. 2021 Mar;44(3):183-190. doi: 10.1016/j.gastrohep.2020.06.016. Epub 2020 Sep 15.
[Article in English, Spanish]

Abstract

Background: Recent evidence suggests that the number of low residue diet (LRD) days does not influence the bowel cleansing quality in non-selected patients. However, there are not data in the subgroup of patients with risk factors of inadequate bowel cleansing.

Objective: The aim of this study was to assess whether a 3-day LRD improved the bowel cleansing quality in patients with risk factors of poor bowel cleansing.

Patients and methods: Post hoc analysis of a randomized controlled trial carried out between December 2017 and March 2018 in a tertiary care hospital. Patients with high risk of poor bowel cleansing were selected following a validated score. The patients were randomized to the 1-day LRD or 3-day LRD groups. All patients received a 2-L split-dose of polyethylene glycol plus ascorbic acid. Intention-to-treat (ITT) and per-protocol (PP) analyses were conducted for the main outcome.

Results: 135 patients (1-day LRD group=67, 3-day LRD=68) were included. The rate of adequate cleansing quality was not significantly different between the groups in the ITT analysis: 76.1%, 95% CI: [64.6-84.8] vs. 79.4%, 95% CI: [68.2-87.4]; odds ratio (OR) 1.2, 95% CI [0.54-2.73]) or in the PP analysis: 77.3%, 95% CI: [65.7-85.8] vs. 80.3%, 95% CI: [69.0-88.3]; OR 1.2, 95% CI [0.52-2.77]). Compliance with the diet or cleansing solution, satisfaction or difficulties with the LRD and the polyp/adenoma detection rates were not significantly different.

Conclusion: Our results suggest that 1-day LRD is not inferior to 3-day LRD in patients with risk factors of inadequate bowel cleansing.

Keywords: Boston Bowel Preparation Scale; Colonoscopia; Colonoscopy; Dieta baja en residuos; Escala de preparación intestinal de Boston; Factores de riesgo de limpieza intestinal deficiente; Low-residue diet; Predictive score; Puntuación predictiva; Risk factors of poor bowel cleansing.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Ascorbic Acid / administration & dosage*
  • Cathartics / administration & dosage*
  • Colonoscopy*
  • Diet / methods*
  • Dietary Fiber*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Patient Compliance / statistics & numerical data
  • Polyethylene Glycols / administration & dosage*
  • Preoperative Period
  • Prospective Studies
  • Single-Blind Method
  • Time Factors

Substances

  • Cathartics
  • Dietary Fiber
  • Polyethylene Glycols
  • Ascorbic Acid