Efficacy and tolerability of high and low-volume bowel preparation compared: A real-life single-blinded large-population study

Superior bowel preparation quality for colonoscopy with 1L-PEG compared to 2L-PEG and picosulphate: Data from a large real-world retrospective outpatient cohort

BACKGROUND

Several randomized clinical trials comparing different bowel preparations (BP) have shown similar efficacy; however, there is a lack of real-world studies on this topic.

AIMS

This study aims to identify the most effective BP regimen in a real-world setting and any predictors of inadequate BP.

METHODS

A retrospective single-center study was conducted over 14 months at an academic hospital including outpatient colonoscopies in which adult patients did not teach on how to perform BP before colonoscopy. Colonoscopies with 1L-PEG, 2L-PEG and picosulphate mixtures were considered. A multivariable analysis for factors associated to poor BP was fitted.

RESULTS

Overall, 1779 patients (51 %F, 60±14) years were included. The 1L-PEG regimen provided a higher rate of BP adequacy at multivariate analysis (adjusted OR 2.30, 95 %CI 1.67-3.16,p < 0.001) and was associated with higher median Boston Bowel Preparation Scale score (p < 0.001), higher rate of right-colon cleansing (p < 0.001) and exam completion (p = 0.04). Furthermore, we identified male sex, history of constipation, active smoking, previous pelvic surgery, concomitant psychiatric/neurological or chronic kidney diseases as predictors of inadequate BP.

CONCLUSIONS

This is the largest real-world study comparing 1L-PEG to other BP regimens. Our results suggest 1L-PEG provides better BP in a non-controlled setting, improving clinical practice quality and minimizing the need for repeated colonoscopies and saving healthcare resources.

The Effects of Combined Use of Linaclotide and Polyethylene Glycol Electrolyte Powder in Colonoscopy Preparation for Patients With Chronic Constipation

OBJECTIVE

The purpose of this study is to evaluate the safety and efficacy of linaclotide and polyethylene glycol (PEG) electrolyte powder in patients with chronic constipation undergoing colonoscopy preparation.

PATIENTS AND METHODS

We included 260 patients with chronic constipation who were scheduled to undergo a colonoscopy. They were equally divided into 4 groups using a random number table: 4L PEG, 3L PEG, 3L PEG+L, and 2L PEG+L. The 4 groups were compared based on their scores on the Boston Bowel Preparation Scale (BBPS) and Ottawa Bowel Preparation Quality Scale (OBPQS), adverse reactions during the bowel preparation procedure, colonoscope insertion time, colonoscope withdrawal time, detection rate of adenomas, and their willingness to repeat bowel preparation.

RESULTS

In terms of the score of the right half of the colon, the score of the transverse colon, the total score using BBPS, and the total score using OBPQS, the 3L PEG (polyethylene glycol)+L group was superior to groups 3L PEG and 2L PEG+L ( P <0.05), but comparable to the 4L PEG group ( P >0.05). The incidence rate of vomiting was higher in the 4L PEG group than in the 2L PEG+L group ( P <0.05). There was no statistically significant difference in the insertion time of the colonoscope between the 4 groups. The colonoscope withdrawal time in the 3L PEG+L group was shorter than in groups 4L PEG and 3L PEG ( P <0.05) and comparable to that in the 4L PEG group ( P >0.05). There was no statistically significant difference in the rate of adenoma detection among the 4 groups ( P >0.05). The 4L PEG group was the least willing of the 4 groups to undergo repeated bowel preparation ( P <0.05).

CONCLUSION

The 3L PEG+L is optimal among the 4 procedures. It can facilitate high-quality bowel preparation, reduce the incidence of nausea during the bowel preparation procedure, and encourage patients to undertake repeated bowel preparation.

3 L split-dose polyethylene glycol is superior to 2 L polyethylene glycol in colonoscopic bowel preparation in relatively high-BMI (≥ 24 kg/m2) individuals: a multicenter randomized controlled trial

BACKGROUND

Whether body mass index (BMI) is a risk factor for poor bowel preparation is controversial, and the optimal bowel preparation regimen for people with a high BMI is unclear.

METHODS

We prospectively included 710 individuals with high BMIs (≥ 24 kg/m2) who were scheduled to undergo colonoscopy from January to November 2021 at 7 hospitals. Participants were randomly allocated into 3 L split-dose polyethylene glycol (PEG) group (n=353) and 2 L PEG group (n=357). The primary outcome was the rate of adequate bowel preparation, and the secondary outcomes included Boston Bowel Preparation Scale (BBPS) score, polyp detection rate, cecal intubation rate, and adverse reactions during bowel preparation. Furthermore, we did exploratory subgroup analyses for adequate bowel preparation.

RESULTS

After enrollment, 15 individuals didn't undergo colonoscopy, finally 345 participants took 3 L split-dose PEG regimen, and 350 participants took 2 L PEG regimen for colonoscopic bowel preparation. 3 L split-dose PEG regimen was superior to 2 L PEG regimen in the rate of adequate bowel preparation (81.2% vs. 74.9%, P = 0.045), BBPS score (6.71±1.15 vs. 6.37±1.31, P < 0.001), and the rate of polyp detection (62.0% vs. 52.9%, P = 0.015). The cecal intubation rate was similar in both groups (99.7%). Regarding adverse reactions, individuals were more likely to feel nausea in the 3 L PEG group (30.9% vs. 19.3%; P = 0.001); however, the degree was mild. In the subgroup analysis for adequate bowel preparation, 3 L split-dose PEG regimen performed better than 2 L PEG regimen in the overweight (BMI 25-29.9 kg/m2 ) (P = 0.006) and individuals with constipation (P = 0.044), while no significant differences were observed in relatively normal (BMI 24-24.9 kg/m2) (P = 0.593) and obese individuals (BMI ≥ 30 kg/m2) (P = 0.715).

CONCLUSIONS

3 L split-dose PEG regimen is superior to 2 L PEG regimen for colonoscopic Bowel Preparation in relatively high-BMI individuals, especially overweight individuals (BMI 25-29.9 kg/m2 ).

TRIAL REGISTRATION

This trial was registered in the Chinese Clinical Trials Registry (ChiCTR2000039068). The date of first registration, 15/10/2020, http://www.chictr.org.cn.

Risk factors for inadequate bowel preparation in patients using high- and low-volume cleansing products

INTRODUCTION

Bowel preparation is crucial for colonoscopy completeness and lesions detection. Today, several cleansing products are equally recommended by guidelines, irrespective of patients' characteristics. Identification of preparation-specific risk factors for inadequate bowel preparation may lead to a personalized prescription of cleansing products to refine patients' tolerance and improve endoscopic outcomes.

METHODS

We prospectively enrolled consecutive outpatients referred for colonoscopy using either a high-volume [HV: 4 l polyethylene glycol (PEG)] or a low-volume (LV: 2 l PEG + bisacodyl) preparation. Day-before regimen or split-dose regimen was used for morning or afternoon colonoscopies, respectively. Univariate and multivariate analyses were conducted to identify risk factors related to inadequate bowel preparation, according to the Boston bowel preparation scale for HV and LV preparations.

RESULTS

We enrolled 2040 patients, of which 1815 were included in the final analysis (average age 60.6 years, 50.2% men). Half of them (52%) used LV preparation. Adequate preparation was achieved by 87.6% without differences between the HV and LV groups (89.2% vs. 86.6%; P = 0.098). The use of day-before regimen and incomplete assumption of PEG were independent predictors of poor visibility for either HV or LV preparation. However, different specific risk factors for HV [diabetes: odds ratio (OR), 3.81; 95% confidence interval (CI), 1.91-7.58; low level of instruction: OR, 1.95; 95% CI, 1.11-3.44; and previous abdominal surgery: OR, 2.27; 95% CI, 1.20-4.30] and for LV (heart disease: OR, 2.06; 95% CI, 1.09-3.88; age > 65 years: OR, 1.51; 95% CI, 1.01-2.27) preparations were identified.

CONCLUSION

Day-before preparation and incomplete assumption of the purgative agents affect bowel visibility irrespective of the preparation volume. LV should be preferred to HV preparations in patients with diabetes, low level of instruction, and previous abdominal surgery, whereas an HV preparation should be preferred in patients with heart disease and in older patients.