EFFECT OF GLUCAGON-LIKE PEPTIDE-1 RECEPTOR AGONISTS ON BOWEL PREPARATION FOR COLONOSCOPY

Abstract

ABSTRACT Background: Inadequate bowel preparation can result in decreased diagnostic accuracy and therapeutic safety of colonoscopy for colon cancer screening. The Boston Bowel Preparation Scale (BBPS) has been used to assess the quality of bowel preparation. Glucagon-Like Peptide-1 Receptor Agonists (GLP-1RAs) are commonly used medications for diabetes mellitus and obesity that are known to delay gastrointestinal motility. We hypothesized that the use of GLP-1RAs would be associated with decreased quality of bowel preparation. Methods: We performed a retrospective cohort study of patients who underwent screening or surveillance colonoscopy at a large academic medical center between December 2021-December 2022. We included patients taking any GLP-1RAs for diabetes or obesity at the time of colonoscopy defined as our cases, and patients who were prescribed GLP-1RAs at one point but not within 3 months of colonoscopy defined as our control. We excluded patients on any promotility or antimotility agents, and those without BBPS recorded on their procedure report. Independent t-tests assessed statistical differences in the case and control groups to compare the quality of bowel preparation for continuous variables and chi-squared test for categorical variables. Multivariate linear regression including diabetes as a covariate was also performed for continuous variables and multivariate logistic regression for categorical variables. Results: A total of 446 patients were included in the study, comprising 265 (59%) cases and 181 controls (41%). There were no statistically significant differences between groups at baseline except for the diagnosis of diabetes (p=0.001) with a higher proportion of patients with diabetes in the cases. Mean BBPS was significantly higher in controls (7.0 ± 1.9 vs. 7.5 ± 2.4, p = 0.046) when controlling for diabetes. The percentage of patients with a total BBPS score of <5 was significantly higher in cases (15.5% vs. 6.6%, p = 0.01). The proportion of patients who required a repeat colonoscopy due to poor bowel prep was also significantly higher in cases (18.9% vs. 11.1%, p = 0.041). Conclusion: The use of GLP-1RAs was associated with a statistically significantly lower quality of bowel preparation, with additional clinical significance given a notable difference in the need for a repeat colonoscopy. It will be essential to understand the cumulative effect of medications that may delay gastric emptying on the quality of bowel preparation to better understand the appropriate measures and counseling that need to be taken before undergoing outpatient colonoscopies.