Comparison of the effect of regular diet and low-fiber diet on bowel cleansing before colonoscopy

Abstract

<jats:title>Abstract</jats:title> <jats:p>BACKGROUNDHigh quality bowel preparation is essential for colonoscopy. A low-fiber diet (LFD), changing people’s dietary habit, is recommended for the day before colonoscopy. The aim of this study was to compare the quality of bowel preparation of regular diet (RD) with that of LFD.METHODSPatients undergoing colonoscopy in the morning were randomly to LFD group, which took a LFD the day before the procedure, or RD group. All patients recieved a split dose of 3L PEG regimen. The diet satisfaction and adverse events were recorded by a questionnaire before colonoscopy. The quality of the bowel preparation was ranked according to the Boston Bowel Preparation Scale (BBPS) by the endoscopists. Per-protocol (PP) and intention-to-treat (ITT) analyses were conducted for the clinical outcomes. A non-inferiority analysis was performed to prove the quality of bowel preparation of RD was not inferior to that of LFD.RESULTS400 patients (200 in RD group, 200 in LFD group) were included. In PP analysis (n = 357), no significant difference was found in the quality of the bowel preparation between the RD group and the LFD group (<jats:italic>P</jats:italic> = 0.440). The diet satisfaction (<jats:italic>P</jats:italic> = 0.978), polyp detection rate (PDR) (<jats:italic>P</jats:italic> = 0.763) and adenoma detection rate (ADR) (<jats:italic>P</jats:italic> = 0.800) were not significantly different between the two groups. Similar results were found in the ITT analysis (n = 400, <jats:italic>P</jats:italic> = 0.440, 0.778, 0.724, 0.893). Hunger in RD group was significantly lower than that in LFD group (<jats:italic>P</jats:italic> = 0.010), especially in young patients (<jats:italic>P</jats:italic> = 0.029) and inpatients (<jats:italic>P</jats:italic> = 0.036).CONCLUSIONThe quality of the bowel preparation of RD is comparable to that of LFD. RD could reduce hunger, especially in young patients and inpatients. Without changing patients’ eating habits, RD may be more acceptable for patients before undergoing colonoscopy.<jats:bold>Trial registration</jats:bold>: Current Controlled Trials ChiCTR1900021836 on 12 March 2019.</jats:p>