Risk of Kidney Failure in Patients With Inflammatory Bowel Disease Undergoing Colectomy: A Nationwide Cohort Study.

Background & Aims: 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: 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.

Results: 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.

Conclusions: 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.