CKD & IBD

May 28, 2024

Issue 11

Clinical Question

What is the risk of chronic kidney disease in IBD patients?

Editor’s Bottom Line

Patients with inflammatory bowel disease have an increased risk of chronic kidney disease. Whether this is driven by systemic inflammation, auto-immunity, metabolic effects of disease or drug toxicity remains unclear.

Reference

Zadora W, Innocenti T, Verstockt B, Meijers B. Chronic kidney disease in inflammatory bowel disease, a systematic review and meta-analysis. J Crohns Colitis. Epub ahead of print April 8, 2024; https://academic.oup.com/ecco-jcc

Synopsis

To quantify the risk of chronic kidney disease (CKD) among patients with IBD, investigators in Italy and Belgium performed a meta-analysis and systematic review of 54 published studies documenting rates of CKD in patients with or without IBD. The definition of CKD varied across studies, although most based a diagnosis using an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m2. Five studies focused on end-stage renal disease (ESRD), defined as an eGFR <15 ml/min/1.73m2, while two studies documented rates of nephritis specifically.

Eight of the studies compared the prevalence of CKD among IBD and non-IBD patients. These studies included 102,230 IBD patients and 762,430 healthy individuals. In five of these studies, a diagnosis of CKD was made using International Classification of Diseases [ICD] codes alone, whereas three studies used eGFR measurements directly as the basis for a CKD diagnosis.

Most of the studies were performed in Europe, while eight were conducted in North America,12 in Asia and three were performed in Africa.

Meta-analysis revealed that IBD patients were 59% more likely to develop CKD than those without IBD [Odds Ratio (OR): 1.59; 95% Confidence Interval (CI), 1.31–1.93]. Use of ICD codes did not alter the magnitude of the association, compared to use of eGFR values directly (OR with ICD codes: 1.70; 95% CI, 1.33–2.19 and OR with eGFR: 1.36; 95% CI, 1.33–1.64).

The risk of CKD reported in the IBD-specific studies ranged from a slightly lower risk of CKD in a small study of 560 IBD and non-IBD subjects to a 2.3-fold increased risk of CKD in a study of roughly 60,000 individuals with or without IBD. In most cohort studies, the absolute risk of CKD in the overall IBD population was approximately 1%.

Systematic review revealed several striking findings, including a higher risk of CKD after IBD diagnosis than before an IBD diagnosis; a lower risk of CKD after IBD diagnosis among patients with later-onset IBD, compared to younger IBD patients; and an elevated risk among Crohn’s disease patients, compared to ulcerative colitis patients.

Details

Study Design: Systematic review and meta-analysis
Funding: None
Allocation: Not applicable
Setting: Multicenter
Level of Evidence: 2a