Preparing for Colonoscopy in People with Diabetes: A Review with Suggestions for Clinical Practice

Glucagon-like peptide-1 receptor agonists significantly affect the quality of bowel preparation for colonoscopy

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) affect gastrointestinal motility, slowing gastric emptying and colonic transit. GLP-1RAs have an impact on gastric residue before endoscopy, but only limited data are available regarding its effect on the adequacy of colonic preparation. We investigated the association between GLP-1RA use and inadequate bowel preparation (IBP) for colonoscopy.

METHODS

We performed a multicenter retrospective study with GLP-1RA cases matched with controls (using propensity scores for age, sex, diabetes mellitus [DM], obesity, and co-morbidities). Data on demographics, medication use, procedural indications, and colonoscopy findings were collected. IBP ("poor preparation" on Aronchik scale or Boston Bowel preparation scale <5) was the primary outcome.

RESULTS

4876 patients treated with GLP-1RAs were included in the analysis and compared with 4876 controls selected from 333 648 patients without GLP-1RA use. Among the GLP-1RA patients, 10% (n = 487) had IBP compared with 197 (4%) of the control group (P<0.001). Subgroup analysis showed a higher rate of IBP among diabetic patients treated with GLP-1RA (284/2364 [12%]) than among diabetic patients without GLP-1RA treatment (118/2364 [5%]; P<0.001). Additionally, 203/2512 nondiabetic patients treated with GLP-1RAs had IBP (8%) compared with 79 of the nondiabetic non-GLP-1RA group (3%; P<0.001). On multivariate analysis, diabetes and GLP-1RA use were both found to be independent risk factors for IBP (odds ratio [OR] 1.4 and OR 2.7, respectively; both P<0.001).

CONCLUSION

Our findings highlight the necessity for special attention and tailored recommendations for both diabetic and nondiabetic patients treated with GLP-1RAs in terms of colonic preparation prior to colonoscopy.

Gastrointestinal pharmacoradiology, an updated review of medications and gastrointestinal contrasts in abdominal imaging

The purpose of this article is to review commonly used medications in abdominal radiology including their indications, mechanisms of action, dosages, contraindications, precautions, and adverse reactions. We will clarify common inquiries and address frequently asked questions by patients and clinicians related to their use. In addition, we will explore the indications, advantages and disadvantages, dosages, and contraindications of enteric contrast agents used for CT and fluoroscopic examinations.

Impact of glucagon-like peptide receptor agonists on endoscopy and its preoperative management: Guidelines, challenges, and future directions

Glucagon-like peptide receptor agonists (GLP-1RA) are used to treat type 2 diabetes mellitus and, more recently, have garnered attention for their effectiveness in promoting weight loss. They have been associated with several gastrointestinal adverse effects, including nausea and vomiting. These side effects are presumed to be due to increased residual gastric contents. Given the potential risk of aspiration and based on limited data, the American Society of Anesthesiologists updated the guidelines concerning the preoperative management of patients on GLP-1RA in 2023. They included the duration of mandated cessation of GLP-1RA before sedation and usage of "full stomach" precautions if these medications were not appropriately held before the procedure. This has led to additional challenges, such as extended waiting time, higher costs, and increased risk for patients. In this editorial, we review the current societal guidelines, clinical practice, and future directions regarding the usage of GLP-1RA in patients undergoing an endoscopic procedure.

Effect of Glucagon-Like Peptide-1 Receptor Agonists on Bowel Preparation for Colonoscopy

INTRODUCTION

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-1RA) are commonly used medications for diabetes mellitus and obesity that are known to delay gastrointestinal motility. We hypothesized that the use of GLP-1RA 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 and December 2022. We included patients taking any GLP-1RA for diabetes or obesity during colonoscopy defined as our cases, and patients who were prescribed GLP-1RA at one point but not within 3 months of colonoscopy defined as our controls. We excluded patients on any promotility or antimotility agents and those without BBPS recorded on their procedure report. Independent t test assessed statistical differences in the case and control groups to compare the quality of bowel preparation for continuous variables, and the χ 2 test was used for categorical variables. Multivariate linear regression including diabetes as a covariate was also performed for continuous variables, and multivariate logistic regression was performed 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. The 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 preparation was also significantly higher in cases (18.9% vs 11.1%, P = 0.041).

DISCUSSION

The use of GLP-1RA 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.

Evaluation of parameters influencing the quality of colon preparation with a split-dose regimen of sulfate salts

BACKGROUND

Bowel cleansing is an important factor for the quality of colonoscopy. We aimed to evaluate the efficacy of split-dose oral sulfate salts on bowel preparation and to determine parameters influencing the quality of bowel cleaning.

METHOD

Consecutive adults who completed their preparation for colonoscopy with a regimen of sulfate salts were enrolled.

RESULTS

Of the 446 patients, 11 were excluded from the analysis. Among the 435 patients, 257 (59.1%) were female, mean age was 62.0±11.6 years and median body mass index (BMI) 26.1 kg/m2 (interquartile range [IQR] 23.8-29.4). Indications for colonoscopy were screening 155 (35.6%), surveillance 102 (23.5%), or other 178 (40.9%). The median time between the end of second dose of the preparation regimen and colonoscopy initiation was 5:15 h (IQR 4:30-6:00, min: 2:20, max: 12:20). Minor adverse events were reported in 62 (14.3%) patients. BBPS=9 was observed in 279 (64.14%) patients. Segmental BBPS=3 was achieved in 387 (88.97%), 346 (79.54%) and 289 (66.44%) patients (P<0.001) in the descending, transverse and ascending colon, respectively. Multivariate analysis revealed that BMI (odds ratio [OR] 1.05, 95% confidence interval [CI] 1-1.1) and time between the end of the second laxative dose and colonoscopy initiation (OR 1.25, 95%CI 1.08-1.45) were associated with poorer bowel preparation.

CONCLUSIONS

A split dose of oral sulfate salts is an efficacious and well tolerated regimen. Obesity and a longer time interval between the end of the second dose and colonoscopy initiation negatively influence bowel cleanliness.