Strategies to Improve Colonoscopy Preparation in Inflammatory Bowel Disease. A Systematic Review and Network Meta-analysis of Randomized Trials

Background and Aims: Colonoscopy has a vital role in the diagnosis of inflammatory bowel disease (IBD), as well as in the estimation of disease severity, monitoring response to therapy, and surveillance for neoplasia. We performed a systematic review of randomised trials of various bowel preparations for colonoscopy in IBD. Methods: We searched various electronic databases (PubMed, Embase, and CENTRAL) for studies reporting about the use of various strategies to improve colonoscopy preparation in IBD. We included only randomized clinical trials (RCTs). A network meta-analysis was done using a frequentist approach to compare the effectiveness of various bowel preparations. The risk of bias was assessed using Cochrane risk of bias tool 2.0. Other outcome parameters like compliance, tolerance, acceptance, and adverse effects were assessed qualitatively. Results: Seven RCTs reporting about 960 patients were included. On comparison with 4 liter (L) of poliethylen glycol (PEG), oral sulfate solution (OR=1.1, 95%CI: 0.65-1.86); PEG2L/Ascorbate (OR=0.98, 95%CI: 0.65-1.48); PEG1L (OR=1, 95%CI: 0.55-1.81); PEG2L plus bisacodyl (OR=1.08, 95%CI: 0.71-1.65); PEG4L plus simethicone (OR=1, 95%CI: 0.67-1.50); PEG/ sodium picosulfate and magnesium citrate (SPMC) 1.5L (OR=0.99, 95%CI: 0.55-1.78); SPMC 2L (OR=1.09, 95%CI: 0.61-1.97) had similar effectiveness. Three RCTs reported compliance, five RCTs reported tolerance, two studies reported patient acceptance and five RCTs reported data on the willingness of patients to repeat the procedure in the future. Low-volume preparations had better compliance, tolerance, acceptance, and willingness to repeat. No difference in additional outcomes like change in disease activity after colonoscopy, procedure-related outcomes after colonoscopy like cecal intubation rate, and change in electrolyte levels were found. Conclusion: Various bowel preparations had similar effectiveness in respect to colonoscopy preparation in IBD patients. Low-volume preparations have better compliance, tolerance, and acceptance. The systematic review was limited by a small number of included RCTs.