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 the impact on tolerability, health-related quality of life (HRQoL) and
work.
Methods: We conducted an open-label, non-inferiority, randomized trial in four Dutch
hospitals. Patients were randomized to 2L polyethylene glycol with ascorbate (2LPEG+Asc)
or 1LPEG+Asc with sodium sulfate. Before and after preparation, patients completed
validated questionnaires on productivity, tolerability, and HRQoL. Primary outcome
was the proportion of patients with adequate bowel preparation, aiming to demonstrate
non-inferiority of 1LPEG+Asc to 2L (5% non-inferiority margin). Secondary outcomes
included willingness-to-repeat, with exploratory analysis of associated factors using
multivariable logistic regression, change in QoL scores, tolerability, and work-related
impact.
Results: We included 467 patients (2LPEG+Asc: n=229,1L PEG+Asc: n=238). 1L PEG+Asc
was non-inferior to 2L PEG+Asc;adequate cleansing rates were 96.1% (95%CI 92.6-98.0%)
vs. 96.4% (95%CI 92.9-98.3%) (p=0.84; Δ -0.4, 95%CI -4.0–3.3). More patients in the
1L PEG+Asc group were willing to repeat the preparation (59.9% vs 48.3%, p=0.04),
with tolerability as the most influential factor (OR=0.05 and OR=0.22 for difficult
or fair vs. good tolerability, adjusted for symptoms, satisfaction, and 1LPEG+Asc/2LPEG+Asc).
No clinically relevant changes in HRQoL were observed. Absenteeism and impaired working
productivity occurred in 7.9% and 12.3%, respectively, with no between-group differences.
Conclusions: Bowel preparation with 1L PEG+Asc is non-inferior to 2L PEG+Asc and has
a higher willingness-to-repeat. Tolerability is fundamental for effective cleansing
and reducing colonoscopy barriers.