Comparing low volume versus intermediate volume bowel preparation and their impact on work and tolerability: an open-label, noninferiority randomized controlled trial

Abstract

Background

Bowel preparation is essential for colonoscopy but may deter patients. Although low volume laxatives are better tolerated, their impact on patient-reported outcomes remains unclear. We compared low and intermediate volume bowel preparation and assessed their impact on tolerability, health-related quality of life (HRQoL), and work.

Methods

We conducted an open-label, noninferiority randomized trial in four Dutch hospitals. Patients were randomized to 2 L polyethylene glycol with ascorbate (2L PEG+Asc) or 1 L with added sodium sulfate (1L PEG+Asc). Before and after preparation, patients completed validated questionnaires on productivity, tolerability, and HRQoL. The primary outcome was the proportion of patients with adequate bowel preparation, aiming to demonstrate noninferiority of 1L PEG+Asc vs. 2L PEG+Asc (5% noninferiority margin). Secondary outcomes included willingness to repeat, with exploratory analysis of associated factors using multivariable logistic regression, change in HRQoL scores, tolerability, and work-related impact.

Results

We included 467 patients (2L PEG+Asc, n = 229; 1L PEG+Asc, n = 238). 1L PEG+Asc was noninferior to 2L: adequate cleansing rate, 96.1% (95%CI 92.6% to 98.0%) vs. 96.4% (95%CI 93.0% to 98.3%; P = 0.84; Δ −0.4, 95%CI −4.0 to 3.3). More patients in the 1L PEG+Asc group were willing to repeat the preparation (59.9% vs. 48.3%; P = 0.04), with tolerability the most influential factor (odds ratios 0.05 and 0.22 for difficult or fair vs. good tolerability, adjusted for symptoms, satisfaction, and 1L/2L PEG+Asc). No clinically relevant changes in HRQoL were observed. Absenteeism and impaired work productivity occurred in 7.9% and 12.3%, respectively, with no between-group differences.

Conclusions

Bowel preparation with 1L PEG+Asc is noninferior to 2L PEG+Asc and associated with higher willingness to repeat. Tolerability is fundamental for effective cleansing and reducing colonoscopy barriers.

Publikationsverlauf

Eingereicht: 12. Februar 2025

Angenommen nach Revision: 03. August 2025

Accepted Manuscript online:
03. September 2025

Artikel online veröffentlicht:
20. Oktober 2025

• References

• 1 Hassan C, East J, Radaelli F. et al. Bowel preparation for colonoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Guideline – Update 2019. Endoscopy 2019; 51: 775-794
• 2 McLachlan S-A, Clements A, Austoker J. Patients’ experiences and reported barriers to colonoscopy in the screening context—a systematic review of the literature. Patient Educ Couns 2012; 86: 137-146
• 3 Zhu Y, Li X, Hu Y. et al. Nonadherence to referral colonoscopy after positive fecal immunochemical test results increases the risk of distal colorectal cancer mortality. Gastroenterology 2023; 165: 1558-1560.e1554
• 4 Spadaccini M, Frazzoni L, Vanella G. et al. Efficacy and tolerability of high- vs low-volume split-dose bowel cleansing regimens for colonoscopy: a systematic review and meta-analysis. Clin Gastroenterol Hepatol 2020; 18: 1454-1465 e1414
• 5 Sharara AI, El Reda ZD, Harb AH. et al. The burden of bowel preparations in patients undergoing elective colonoscopy. United European Gastroenterol J 2016; 4: 314-318
• 6 Collatuzzo G, Fuccio L, Frazzoni L. et al. Determinants of symptom burden related to bowel preparation for colonoscopy. Dig Liver Dis 2022; 54: 1554-1560
• 7 Fuccio L, Collatuzzo G, Frazzoni L. et al. Impact of colonoscopy on working productivity: a prospective multicenter observational study. Gastrointest Endosc 2022; 95: 550-561.e8
• 8 Bronzwaer MES, Depla A, van Lelyveld N. et al. Quality assurance of colonoscopy within the Dutch national colorectal cancer screening program. Gastrointest Endosc 2019; 89: 1-13
• 9 Nguyen DL, Wieland M. Risk factors predictive of poor quality preparation during average risk colonoscopy screening: the importance of health literacy. J Gastrointestin Liver Dis 2010; 19: 369-372
• 10 Bouwmans C, Krol M, Severens H. et al. The iMTA Productivity Cost Questionnaire: a standardized instrument for measuring and valuing health-related productivity losses. Value Health 2015; 18: 753-758
• 11 Niv Y, Bogolavski I, Ilani S. et al. Impact of colonoscopy on quality of life. Eur J Gastroenterol Hepatol 2012; 24: 781-786
• 12 Mahabaleshwarkar R, Khanna R, West-Strum D. et al. Association between health-related quality of life and colorectal cancer screening. Popul Health Manag 2013; 16: 178-189
• 13 Patel M, Staggs E, Thomas CS. et al. Development and validation of the Mayo Clinic Bowel Prep Tolerability Questionnaire. Dig Liver Dis 2014; 46: 808-812
• 14 Veldhuijzen G, de Jong MJP, Roosen CM. et al. The gastrointestinal endoscopy satisfaction questionnaire captures patient satisfaction as a key quality indicator of gastrointestinal endoscopy. Eur J Gastroenterol Hepatol 2020; 32: 832-837
• 15 Versteegh MM, Vermeulen KM, Evers SMAA. et al. Dutch tariff for the five-level version of EQ-5D. Value Health 2016; 19: 343-352
• 16 Norman GR, Sloan JA, Wyrwich KW. Interpretation of changes in health-related quality of life: the remarkable universality of half a standard deviation. Med Care 2003; 41: 582-592
• 17 López-Jamar JME, Gorjão R, Cotter J. et al. Bowel cleansing effectiveness and safety of 1L PEG + Asc in the real-world setting: Observational, retrospective, multicenter study of over 13000 patients. Endosc Int Open 2023; 11: E785-E793
• 18 Bednarska O, Nyhlin N, Schmidt PT. et al. The effectiveness and tolerability of a very low-volume bowel preparation for colonoscopy compared to low and high-volume polyethylene glycol-solutions in the real-life setting. Diagnostics 2022; 12: 1155
• 19 Repici A, Spada C, Cannizzaro R. et al. Novel 1-L polyethylene glycol + ascorbate versus high-volume polyethylene glycol regimen for colonoscopy cleansing: a multicenter, randomized, phase IV study. Gastrointest Endosc 2021; 94: 823-831 e829
• 20 Bisschops R, Manning J, Clayton LB. et al. Colon cleansing efficacy and safety with 1 L NER1006 versus 2 L polyethylene glycol + ascorbate: a randomized phase 3 trial. Endoscopy 2019; 51: 60-72
• 21 DeMicco MP, Clayton LB, Pilot J. et al. Novel 1 L polyethylene glycol-based bowel preparation NER1006 for overall and right-sided colon cleansing: a randomized controlled phase 3 trial versus trisulfate. Gastrointest Endosc 2018; 87: 677-687 e673
• 22 Shafer LA, Walker JR, Waldman C. et al. Predictors of patient reluctance to wake early in the morning for bowel preparation for colonoscopy: a precolonoscopy survey in city-wide practice. Endosc Int Open 2018; 06: E706-E713
• 23 Andronis L, Waugh N, Zanganeh M. et al. Impact of colonoscopy on health-related quality of life: findings from the RECEDE study. Health Qual Life Outcomes 2024; 22: 49
• 24 Swan JS, Hur C, Lee P. et al. Responsiveness of the testing morbidities index in colonoscopy. Value Health 2013; 16: 1046-1053
• 25 Ko CW, Riffle S, Shapiro JA. et al. Incidence of minor complications and time lost from normal activities after screening or surveillance colonoscopy. Gastrointest Endosc 2007; 65: 648-656
• 26 Dong MH, Kalmaz D, Savides TJ. Missed work related to mid-week screening colonoscopy. Dig Dis Sci 2011; 56: 2114-2119
• 27 Heitman SJ, Au F, Manns BJ et al. Nonmedical costs of colorectal cancer screening with the fecal occult blood test and colonoscopy. Clin Gastroenterol Hepatol 2008; 6: 912–917.e911.
• 28 Rex DK, Imperiale TF, Latinovich DR. et al. Impact of bowel preparation on efficiency and cost of colonoscopy. Am J Gastroenterol 2002; 97: 1696-1700
• 29 Nguyen DL, Jamal MM, Nguyen ET. et al. Low-residue versus clear liquid diet before colonoscopy: a meta-analysis of randomized, controlled trials. Gastrointest Endosc 2016; 83: 499-507 e491
• 30 Wang F, Huang X, Wang Z. et al. One-day versus three-day low-residue diet bowel preparation regimens before colonoscopy: a meta-analysis of randomized controlled trials. J Gastroenterol Hepatol 2024; 39: 787-795
• 31 Jain S, Galoosian A, Wilhalme H. et al. Individuals with a family history of colorectal cancer warrant tailored interventions to address patient-reported barriers to screening. Clin Transl Gastroenterol 2023; 14: e00583
• 32 Serper M, Gawron AJ, Smith SG. et al. Patient factors that affect quality of colonoscopy preparation. Clin Gastroenterol Hepatol 2014; 12: 451-457