A randomized, controlled, double-blind trial of the adjunct use of tegaserod in whole-dose or split-dose polyethylene glycol electrolyte solution for colonoscopy preparation

BackgroundProblems of compliance, quality, and safety of colon preparation regimens have prompted continued investigation with alternative forms of cleansing.ObjectiveTo evaluate the efficacy of tegaserod as an adjunct to a polyethylene glycol electrolyte solution (PEG-E), given as a whole dose or split dose, in colonoscopy preparation.DesignRandomized, placebo-controlled, double-blind trial.SettingA single university-based hospital.PatientsPatients who were undergoing elective colonoscopy.InterventionsA 4-arm randomization scheme that compared tegaserod with a placebo, each with whole-dose or split-dose PEG-E preparation.Main Outcome MeasurementsEfficacy of colon cleansing was the primary outcome. Secondary outcomes included adherence, tolerability, adverse effects, and patient perceptions of their preparation quality.ResultsA total of 382 patients completed the trial. Patients who received the split-dose preparation had significantly better colon cleansing than those who received the whole-dose preparation (88.9% vs 42.6%, P < .001). The addition of tegaserod did not significantly improve the overall colonoscopy preparation quality compared with a placebo. However, there were fewer poor preparations in the whole-dose PEG-E group (12.4% vs 1.1%, P = .002, Bonferroni correction removes significance) and more excellent preparations in the split-dose group (53.3% vs 38.3%, P = .035, Bonferroni correction removes significance) in favor of tegaserod. Interobserver and intraobserver variability analysis showed substantial agreement among endoscopists. Adherence was significantly lower in the whole-dose group versus the split-dose PEG-E group (68.8% vs 91%, P < .001), independent of the use of tegaserod. Adverse effects were not different between study groups.LimitationsA 4-arm randomization and the single-center nature of the study.ConclusionsTegaserod has a marginal effect on the quality of colonoscopy preparation when used as an adjuvant to PEG-E. The split-dose PEG-E was superior to the whole-dose PEG-E and resulted in better colon cleansing, adherence, and tolerance.