Risk of kidney failure in patients with inflammatory bowel disease undergoing colectomy: a nationwide cohort study

Abstract

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. This study was a nationwide Swedish cohort study comprising 82,051 individuals with biopsy-proven IBD diagnosed during 1965 to 2017, with follow-up until 2019. We investigated the association between incident colectomy (time-varying exposure) and future risk of acute kidney injury (AKI) and 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/duration of a stoma. Covariates included demographics, education level, and selected comorbidities. Over a median follow-up of 14 years, 16,479 individuals underwent colectomy, and 2556 AKI and 1146 kidney failure events occurred. Colectomy was associated with an increased relative risk of both AKI (adjusted hazard ratio, 2.37; 95% confidence interval, 2.17-2.58) and kidney failure (adjusted hazard ratio, 1.54; 95% confidence interval, 1.34-1.76). Compared with pre-colectomy periods, undergoing total colectomy and colectomy with prolonged stoma showed higher risks of both kidney outcomes versus partial colectomy or colectomy with a temporary stoma, respectively. Subgroup analyses suggested higher risks in patients with ulcerative colitis. In people with IBD, rates of AKI and kidney failure are higher among those undergoing colectomy, particularly among those following total colectomy, or colectomy with a prolonged stoma. This study identifies a high-risk population that may benefit from established protocols for kidney function monitoring/surveillance and referral to nephrologist care.