S589 One-Liter Polyethylene Glycol + Ascorbic Acid Bowel Preparation Delivers High Levels of Adequate and High-Quality Bowel Cleansing for Colonoscopy: A Real-World, Multicenter, Observational Study of Over 13,000 Patients

Introduction: 1L polyethylene glycol + ascorbic acid preparation (1L PEG+ASC) has shown high bowel cleansing efficacy in clinical trials. Here we report the largest real-world study on 1L PEG+ASC effectiveness to date. Methods: An observational, multicenter, retrospective study evaluated outpatients who underwent a colonoscopy between July 2019 and September 2021 at 12 centers in Spain and Portugal. Adults (aged ≥18 years) who had a screening, surveillance, or diagnostic colonoscopy after 1L PEG+ASC as an evening/morning (split dose) or same-day regimen were included. Bowel cleansing was assessed using the Boston Bowel Preparation Scale (BBPS). Adequate cleansing success was defined as a total BBPS score ≥6 with all segmental scores ≥2. Segmental BBPS scores of 3 defined high-quality cleansing. Safety was assessed through registered adverse events (AEs). Cleansing rates between subgroups were compared with the Chi-square test and BBPS scores with the Wilcoxon rank-sum test. Results: A total of 13,169 patients were included; 48.6% of patients were male, mean (SD) age was 57.0 ± 13.1 years. The main colonoscopy indication was screening (41.9%), followed by diagnostic (29.4%). Most patients (67.2%) received a same-day dosing regimen. Overall cleansing success was achieved in 89.3% (95% CI: 88.7%–89.8%) of patients. High-quality cleansing of the right colon was attained in 49.3% of patients (95% CI: 48.4%–50.2%). The split-dose regimen attained superior adequate colon cleansing success versus the same-day regimen (94.7% vs. 86.7%; P < 0.0001) and superior high-quality cleansing of the right colon (65.4% vs. 41.4%; P < 0.0001). Rates of adequate bowel cleansing per segment were high for all regimens (Figure A). Overall and segmental BBPS scores were significantly greater with the split-dose versus same-day regimen (Figure B). Effect of time to colonoscopy on mean overall BBPS score was statistically significant in patients receiving same-day dosing (Figure C). Colonoscopy was completed in 97.3% of patients; only 0.8% of procedures were incomplete due to poor preparation. The incidence of AEs was 2.3% (95% CI: 2.0%–2.5%); the main AEs were nausea (1.2%), vomiting (0.8%), and abdominal pain (0.2%). Conclusion: Results from this large study confirm the high cleansing effectiveness and good tolerability of 1L PEG+ASC in real-world settings.Figure 1.: Bowel cleansing performance of 1L PEG+ASC: (A) Rates of segmental-level adequate-cleansing (BBPS score ≥2); (B) Mean BBPS score for the overall colon and per colon segment; (C) Effect of time to colonoscopy on mean BBPS score in patients receiving same-day or split dose regimens.