[Timing of polyethylene glycol administration is a key factor in the tolerability and efficacy of colon preparation in colorectal cancer screening]

Abstract

Introduction: The quality and tolerability of antegrade gut lavage bowel preparation are key elements in the success of population-based colorectal cancer screening.

Objectives: To evaluate cleansing quality and tolerability according to the timing of polyethylene glycol administration in persons undergoing colorectal cancer screening.

Method: Participants in colorectal cancer screening were randomized to two groups: a) control group (colonoscopy scheduled at 9-12 h); preparation with polyethylene glycol on the previous afternoon; b) study group (colonoscopy scheduled at 12-15 h): preparation with polyethylene glycol on the morning of the colonoscopy, with the option of a split dose. The quality of cleansing was evaluated with the Boston scale and tolerability through a questionnaire.

Results: A total of 282 participants were included: preparation was carried out the day before the procedure in 134 and on the same day in 148, of which 26 received a split dose. Cleansing was adequate in 95% (n=268) of the participants. The quality of cleansing was higher in the study group (P=.045). The interval between the end of administration and the beginning of the procedure was inversely correlated with the Boston scale score (P=.036; r=-0.125). Tolerability was unrelated to the time of administration (P>.2). Acceptance of the timing of administration was lower in the study group than in the control group (26% vs 10%, respectively; P=.001).

Conclusions: Preparation as close as possible to the colonoscopy improves the quality of cleansing with no detrimental effects on tolerability, although this option is less comfortable.