Effect of chewing gum combined with WeChat-enhanced instruction on bowel preparation in constipated patients: a randomized-controlled trial.

Background and aims: Constipated patients have higher risk of poor bowel preparation and suffer from dysfunction of the intestinal motor. Chewing gum can stimulate gut motility and enhanced instructions can improve the quality of bowel preparation. The objective of this study was to investigate whether chewing gum combined with WeChat-enhanced instruction can increase the quality of bowel preparation in constipated patients.

Methods: This was a single-center, endoscopist-blinded, randomized-controlled trial. Patients were assigned (1:1) to the chewing gum and WeChat-enhanced instruction (CGW) group and the control group. Patients in both groups received 3 L of polyethylene glycol (PEG) before colonoscopy. Patients in the CGW group were asked to chew one piece of gum for 20 min after drinking each 1 L of PEG and received enhanced instruction via WeChat the day before colonoscopy. The quality of the bowel preparation (primary outcome), adenoma and/or polyp detection rate (ADR/PDR), number of polyps and/or adenomas, procedure time, and adverse events were compared.

Results: A total of 115 patients were finally analysed, including 60 in the CGW group and 55 in the control group. The proportion of adequate bowel preparation and the Boston Bowel Preparation Scale score were not statistically different between the two groups (76.7% vs 70.9%; 6.80 ± 1.42 vs 6.40 ± 1.78; both P > 0.05). There was no significant difference in the ADR/PDR and number of polyps and/or adenomas (both P > 0.05). However, there was a significantly higher incidence of nausea in the CGW group than in the control group (33.3% vs 16.4%, P = 0.036).

Conclusions: Chewing gum combined with WeChat-enhanced instruction does not improve the quality of bowel preparation for colonoscopy in constipated patients but does increase the incidence of nausea.