IDDF2021-ABS-0117 Prevalence of pouchitis in both ulcerative colitis and familial adenomatous polyposis; a systematic review and meta-analysis

Background Pouchitis is a clinically significant complication of ileal pouch–anal anastomosis (IPAA) with its prevalence varying in the literature. Pouchitis is thought to occur more commonly in patients with Ulcerative Colitis (UC) than Familial Adenomatous Polyposis (FAP). We conducted a systematic review with a meta-analysis of all published literature to report the prevalence of acute and chronic pouchitis in UC and FAP. Methods A PRISMA meta-analysis was conducted by searching the Embase, Embase classic and Pubmed databases between 1970 –2021 to identify studies that reported the incidence of pouchitis. We combined the proportion of patients with pouchitis in each study to give a pooled prevalence. We then performed a random-effects model in order to pool the data to provide an estimate of the prevalence of pouchitis. Heterogeneity was assessed using the I2 statistic. All statistics were carried out using R with the package ‘meta’. Results In total, 4709 abstracts were screened with 26 full papers and conference abstracts meeting the inclusion criteria. Our analysis showed that in patients with UC; the prevalence of acute pouchitis was 0.18 (95%CI: 0.15-0.22) with a significant heterogeneity of I2= 89% P Conclusions Our findings support the consensus that the prevalence of pouchitis is higher in UC than in FAP and higher in acute than in chronic. More significantly, our findings suggest that the true prevalence of pouchitis is higher than commonly reported in the literature. This literature may help counsel patients prior to undergoing restorative proctocolectomy, especially in those with ulcerative colitis who have often had to live for many years with the consequences of colonic mucosal inflammation.