Randomized clinical trial evaluating three low-volume preparations for colonoscopy in outpatients with Inflammatory Bowel Disease: the EII-PREP trial.

BACKGROUND: Data regarding bowel preparation in patients with Inflammatory Bowel Disease (IBD) are scarce. AIM: To compare efficacy, safety, and tolerability of low-volume preparations in patients with IBD. METHODS: Single-center, randomized, prescriber, and colonoscopist-blinded clinical trial. IBD outpatients undergoing colonoscopy were randomized 1:1:1 to receive 1 Liter-polyethylene glycol-ascorbate (1L-PEG), 2 Liters-PEG, or sodium picosulfate (SP). The primary endpoint was percentage of quality cleansing assessed via the Boston Bowel Preparation Scale (BBPS ≥6, segments ≥2). Secondary endpoints were total high quality cleansing (BBPS 8 or 9), high-quality segmental BBPS (≥2), and patients' tolerability, symptoms, and satisfaction, assessed by questionnaires. Safety was monitored by adverse event reporting, laboratory evaluation at colonoscopy, and telephonic follow-up. RESULTS: Ninety-two patients were included (33 1L-PEG, 28 2L-PEG, and 31 SP). No significant differences between preparations were observed in quality or high-quality total BBPS or high-quality segmental BBPS. Complete intake of the solution was higher for SP (p = 0.006) and lower for 1L-PEG (p = 0.02) compared to 2L-PEG intake (p = 0.55). Clinically irrelevant hyponatremia was higher in the SP group (p < 0.0001). SP instructions were easier to understand from patient's point of view (p = 0.01). Willingness to retake was higher with SP (p < 0.0001) and less for 1L-PEG (p < 0.0001). No serious adverse events were reported. CONCLUSIONS: We observed no differences in efficacy between low-volume preparations in patients with IBD. Complete intake was higher for SP and lower for 1L-PEG. SP and 2L-PEG instructions were better understood and graded, and SP was more likely to be retaken. Willingness to retake was lower for 1L-PEG. No serious adverse events were reported. SUMMARY: No differences in terms of efficacy were regarded in this clinical trial comparing low-volume preparations for colonoscopy in patients with IBD: however, Sodium Pisoculfate is better tolerated and accepted from patient's point of view. No serious adverse events were reported.