Use of glucagon‐like peptide‐1 receptor agonists is associated with inadequate bowel preparation for colonoscopy in patients with diabetes

AIMS/INTRODUCTION: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) delay gastric emptying and may impair bowel preparation for colonoscopy. However, evidence in Asian populations is limited, and the impact of dosing frequency remains unclear. We examined the association between GLP-1RA use and inadequate bowel preparation in Japanese patients with diabetes and compared weekly and daily formulations. MATERIALS AND METHODS: This single-center retrospective observational study included Japanese patients with diabetes who underwent colonoscopy at Kameda Medical Center between October 2021 and September 2024. Bowel preparation quality was assessed using the Aronchick scale; fair, poor, and inadequate were classified as inadequate preparation. Propensity score matching was performed using age, sex, chronic kidney disease, HbA1c, and insulin use. Additional multivariable logistic regression and sensitivity analyses were performed. RESULTS: Among 997 eligible patients, 90 propensity score-matched pairs were identified. Inadequate preparation was more frequent in GLP-1RA users than non-users after matching (32.2% vs 16.7%; relative risk 1.933, 95% CI 1.115-3.353; P = 0.024). Additional analyses showed similar directional associations, although statistical significance was attenuated. Weekly formulations were associated with a higher rate of inadequate preparation than daily formulations (44.2% vs 22.9%; relative risk 1.928, 95% CI 1.039-3.577; P = 0.044). CONCLUSIONS: In Japanese patients with diabetes, GLP-1RA use was associated with a higher rate of inadequate bowel preparation in the propensity score-matched analysis, although additional adjusted analyses were not statistically significant. The finding for weekly formulations should be interpreted cautiously.