COMPARISON BETWEEN AN ASYMMETRIC AND SYMMETRIC SPLIT-DOSE REGIMEN OF POLYETHYLENE GLYCOL PLUS BISACODYL FOR BOWEL PREPARATION FOR SCREENING COLONOSCOPY: A RANDOMIZED NON INFERIORITY CLINICAL TRIAL

Aims:

Bowel cleansing has a critical role to increase quality and effectiveness of colonoscopy. International guidelines recommend the use of split dose regimens of PEG solutions. The adoption of split dose regimens in clinical practice remains sub-optimal, in particular in early morning.

Methods:

We aimed to compare the efficacy of bowel preparation using an asymmetric split-dose regimen (approximately 25% of the dose is given on the day of the procedure and 75% of the dose is given on the day before) with the standard split-dose regimen in patients undergoing screening colonoscopy, enrolled consecutively. Patients were randomly assigned to: group A, asymmetric split dose regimen (1,5 L of PEG + bisacodyl the day before and 0,5 L 3 hours before colonoscopy); group B, symmetric split dose regimen (1 L of PEG + bisacodyl the day before and 1 L 4 hours before colonoscopy). The primary endpoints were the proportion of adequate bowel cleansing.

Results:

179 patients were enrolled (mean age 60 ± 8 years, males 56%), 88 in group A and 91 in group B. Split-dose was taken by 76/88 and by 77/91 patients in group A and B, respectively (85.2% vs. 88.5%, p = 0.831). In the ITT analysis, bowel cleansing was considered adequate in 71/76 (93.4%) and 70/77 (90.9%) patients respectively. in group A and B (p = 0.765). No differences were observed regarding adenoma detection rate [32/76 (42.1%) vs. 35/77 (45.4%); p = 0.745)] and scores of each colon segment. The full amount of product and adjunctive fluids were taken by 68/76 (89.4) and 71/77 (92.2%) (p = 0.158) in group A and B, respectively.

Conclusions:

An asymmetric split-dose preparation is not inferior to the standard split-dose regimen in achieving an adequate bowel cleansing in patients undergoing screening colonoscopy, allowing them to wake up later. Further study are needed to determine the efficacy of the asymmetric preparation for colonoscopy scheduled in early morning.