Patients with Crohn’s disease (CD) are at higher risk of end-stage renal disease (ESRD), investigators from South Korea reported.
In a retrospective study using the National Health Insurance database in South Korea, Joo Sung Kim, MD, PhD, of Seoul National University College of Medicine, and colleagues compared 38,812 patients with inflammatory bowel disease (IBD)—either CD or ulcerative colitis (UC)—with 116,436 age- and sex-matched controls without IBD. During a mean follow-up period of .9 years, ESRD was diagnosed in 79 patients with IBD (0.2%) and 166 controls (0.1%). The incidence of ESRD, per 1000 person-years, was 0.42 in the IBD group compared with 0.29 among controls. The incidence of ESRD was significantly higher among patients with CD compared with controls (0.51 vs 0.13), Dr Kim’s team reported in the World Journal of Gastroenterology. In adjusted analyses, the CD group had a significant 6.3-fold greater risk of ESRD than controls. In contrast, the incidence of ESRD in the UC and control patients did not differ significantly (0.37 for both).
“Patients with CD should be monitored carefully for signs of renal insufficiency,” the investigators concluded.
The mortality rates for the overall IBD group and control group did not differ significantly.
Dr Kim and colleagues discussed various mechanisms by which ESRD risk is higher in patients with CD. “First, ESRD may result from a systemic inflammatory response via an immunologic mechanism that determines the disease activity of the intestines,” they explained. The authors cited studies showing that low-grade systemic inflammation contributes to renal dysfunction, and this consequently has emerged as a novel risk factor for ESRD. Other studies showed that serum C-reactive protein (CRP) levels are elevated in patients with ESRD who initiated dialysis, and CRP levels are elevated in patients with CD, but not UC.