DOP51 Risk of kidney failure in patients with Inflammatory Bowel Disease undergoing colectomy: a nationwide cohort study

Abstract Background Inflammatory bowel disease (IBD) is frequently accompanied by kidney complications. Potential triggers or subpopulations at high-risk of kidney problems are not well elucidated. We hypothesized that surgical interventions, specifically colectomy, might in part explain this risk. Methods A nationwide Swedish cohort study comprising 82,052 individuals with biopsy-proven IBD diagnosed during 1965-2017, with follow-up until 2019. We investigated the association between incident colectomy (time-varying exposure) and future risk of kidney failure (diagnosis of end-stage kidney disease or death due to chronic kidney disease) using Cox proportional hazard models. We also examined the impact of partial vs. total colectomy and the presence of a stoma. Covariates included age, sex, education level, and selected comorbidities. Results Over a median follow-up of 14 years, 15,922 individuals underwent colectomy, and 952 kidney failure events occurred. Colectomy was associated with an increased relative risk of kidney failure (adjusted hazard ratio [aHR] 1.60; 95% CI 1.39-1.84). Compared to periods without colectomy, undergoing total colectomy (aHR 1.82; 95% CI 1.54-2.15) and colectomy with the presence of a stoma (aHR 2.40; 95% CI 1.75-3.28) showed higher risks versus partial colectomy or colectomy without a stoma, respectively. Subgroup analyses revealed higher kidney failure risk in patients with ulcerative colitis and those aged ≥40 years at IBD diagnosis. In absolute risks, at 30-year after colectomy, 8.9% of patients with IBD had kidney failure, with an absolute risk difference of 4.5% (95% CI 1.9-7.0%). Conclusion In people with IBD, rates of kidney failure are higher among those undergoing colectomy, particularly following total colectomy or colectomy with a stoma. This study identifies a high-risk population that may benefit from established protocols for kidney function monitoring/surveillance and referral to nephrologist care.