Phosphate tablets or polyethylene glycol for preparation to colonoscopy? A multicentre non-inferiority randomized controlled trial

Stanislas Chaussade, Christoph Schmöcker, Pierre Toulemonde, Miguel Muñoz-Navas, Valérie O’Mahony, Franck Henri

Adequate bowel preparation is a crucial step in colonoscopy procedure and has been identified as the cornerstone of a quality colonoscopy. Polyethylene glycol (PEG) for bowel cleansing still had up to 10 % unprepared colon. We herein compare efficacy, acceptability, tolerance and safety of sodium phosphate (NaP) tablets and split-dose PEG for bowel cleansing. A prospective non-inferiority randomized trial was performed and registered on www.clinicaltrials.gov (NCT01840553). Patients were randomized to either 32 NaP tablets or 4 L of PEG. Blind readers assessed the efficacy of colon cleansing using the Boston Bowel Preparation Scale (BBPS). A total of 461 patients were randomized in groups (NaP group: n = 231; PEG group: n = 230). Median age was 54 and 52 in NaP group and PEG group, respectively (p < 0.01). Patients experienced an overall compliance to the treatment in 99.6 and 94.1 % in the NaP group and in the PEG group, respectively (p < 0.001). The mean time of withdrawal was 15.1 ± 8.9 and 15.4 ± 9.5 min in the NaP group and in the PEG group, respectively (p = 0.95). The good quality of bowel preparation, defined as BBPS score ≥7, was obtained in 86.4 and 89.0 % of cases in the NaP group and in the PEG group, respectively (p = 0.42). In all segment (right colon, transverse colon and left colon and rectum), the NaP group was non-inferior to the PEG group. Bowel prep regimen was more frequently considered as "easy" by patients from the NaP group (54.8 % of patients) than patients from the PEG group (29.0 % of patients; p < 0.001). No serious adverse events were reported. No statistical differences were found between the NaP group and the PEG group concerning the incidence of an adverse event (338 vs. 322, respectively). While NaP tablets appeared as efficient as PEG in terms of colon cleansing prior to a colonoscopy, they significantly improved the overall compliance and eased product administration. At an era where bowel cleansing appears to be the cornerstone of a quality colonoscopy, NaP tablets in patients without contraindication might be considered as an option.