Mandatory vs. optional split-dose bowel preparation for morning colonoscopies: a pragmatic noninferiority randomized controlled trial

Abstract

BACKGROUND: We compared the effectiveness of optional split-dose bowel preparation (SDBP) to mandatory SDBP for morning colonoscopies in usual clinical practice. METHODS: Adult patients undergoing outpatient early morning (8:00am-10:30am) and late morning (10:30am-12:00pm) colonoscopies were included. Written BP instructions were provided based on randomization: One group was instructed to take their BP (4L polyethylene glycol solution) as a split-dose (mandatory), while the comparator group was allowed the choice of SDBP or single dose BP administered entirely the day before (optional). The primary endpoint, using non-inferiority hypothesis testing with a 5% margin, was adequate bowel cleanliness measured by the Boston Bowel Preparation Scale (BBPS) and defined by a BBPS score ≥6. RESULTS: Among 770 randomized patients, there were 267 mandatory SDBP and 265 optional SDBP for early morning, and 120 mandatory SDBP and 118 optional SDBP patients for late morning colonoscopies with completed data. Optional SDBP was inferior to mandatory SDBP with lower proportion of adequate BBPS cleanliness among early morning colonoscopies [78.9% vs 89.9%, absolute risk difference (aRD)11.0%, 95%CI (5.9%, 16.1%)], but was not statistically different for late morning colonoscopies [76.3% vs 83.3%, aRD 7.1%, 95%CI (-1.5%, 15.5%). CONCLUSIONS: Optional SDBP is inferior to the mandatory SDBP in providing adequate BP quality for early morning colonoscopies (8:00am-10:30am), and probably inferior among late morning colonoscopies (10:30am-12:00pm). ClincialTrials.gov number, NCT03650725.

One‐day versus three‐day low‐residue diet bowel preparation regimens before colonoscopy: a meta‐analysis of randomized controlled trials

“…5 Bowel preparation is a relatively complex process that is influenced by various factors, including the kind of laxative type, split or non-split dose, interval between the last of preparation and the start of colonoscopy, diet restriction, and patient's tolerability. [6][7][8][9] Dietary restrictions may have a significant impact on patient compliance, quality of life, and willingness to repeat colonoscopy. 10 Traditionally, patients are required to ingest only clear-liquid diet (CLD) the day before colonoscopy.…”