Effect of Diet Liberalization on Bowel Preparation

Area of Science:

• Gastroenterology
• Clinical Nutrition
• Medical Research Methodology

Background:

• Precolonoscopy dietary regimens are often restricted to clear liquids.
• The superiority of a clear liquid diet (CLD) for bowel preparation quality is not definitively established.

Purpose of the Study:

• To compare bowel preparation outcomes between a low-residue diet (LRD) or regular diet (RD) and a CLD using a meta-analysis of randomized trials.

Main Methods:

• A comprehensive literature search was conducted across multiple databases for randomized controlled trials from 1976 to March 2015.
• Twelve studies met inclusion criteria, with 7 classified as high quality.
• Bowel preparation quality (adequate vs. inadequate), tolerability, willingness to repeat, adverse events, and adenoma detection rate were assessed.

Main Results:

• High-quality studies showed no significant difference in bowel preparation quality between LRD/RD and CLD groups (RR 0.98; 95% CI 0.93-1.04).
• Tolerability (RR 1.04, 95% CI 1.01-1.08) and willingness to repeat bowel preparation favored liberalized diets (LRD/RD) (RR 1.08, 95% CI 1.01-1.16).
• No significant difference in adenoma detection rate was observed; hunger was more prevalent in the CLD group.

Conclusions:

• A low-residue diet or regular diet offers comparable bowel preparation quality to a clear liquid diet.
• Liberalized precolonoscopy diets may be a reasonable option for patients without risk factors for poor preparation, enhancing tolerability and repeat willingness.