Day before late regimen vs standard split dose of low-volume PEG-CS for early morning colonoscopy: Multicenter randomized controlled trial

Background and study aims Despite lower patient adherence, the overnight split-dose (SD) intestinal preparation regimen is currently recommended for early morning colonoscopies. Using low-volume preparation, we compared performance of a "day before late" (DBL) regimen, with the whole preparation taken between 8.30 pm and midnight on the day before the endoscopic procedure vs the overnight SD regimen for colonoscopies scheduled between 8 am and 10 am. Patients and methods Patients were randomized to the DBL group (n = 162) or SD group (n = 158). The SD group took the second dose 5 hours before colonoscopy. Successful bowel cleansing, defined as an overall Boston Bowel Preparation Score >= 3, safety, compliance and tolerability were assessed in the two groups. Results The DBL regimen failed to demonstrate non-inferiority compared with the SD regimen in terms of successful bowel cleansing (DBL, 88.2 % vs SD, 98.1%, P < 0.001). Subgroup analysis on colonoscopies before 9 am showed BBPS >= 3 rates of 94.6% and 100% in the DBL and SD groups, respectively P = 0.126). The two regimens showed similar compliance and tolerability. Compared with SD patients (25.5%), a lower proportion of DBL patients (13.9%) reported fear of incontinence during the journey to the hospital ( P = 0.01). Conclusions Albeit more tolerable, the DBL regimen was less effective than the SD regimen with regard to successful bowel cleansing for colonoscopies between 8 am and 10 am. Subgroup analysis on colonoscopies scheduled before 9 am showed that the two regimens have similar efficacy, suggesting that the DBL regimen may be a valuable alternative to the SD regimen for very early morning colonoscopies.