Inflammatory bowel disease factors in chronic kidney disease

Inflammatory bowel disease (IBD) contributes to an increased risk of developing chronic kidney disease (CKD), with the risk highest for younger patients, as shown in a study. Meanwhile, the use of IBD medications does not offer a protective benefit.

Researchers used data from The Health Improvement Network and reviewed the medical records of 17,807 IBD patients and 63,466 matched controls in relation to the risk of developing CKD stages 3–5D. They also assessed the effect of using IBD medications such as 5-aminosalicylic acid (5-ASA), azathioprine and methotrexate on estimated glomerular filtration rate (eGFR).

In multivariable Cox proportional hazards models adjusted for risk factors associated with CKD, IBD showed an association with the risk of developing CKD in patients aged 16–77 years, with the risk notably decreasing with age.

Specifically, the adjusted hazard ratio for CKD declined from 7.88 (95 percent confidence interval [CI], 2.56–24.19) at age 16 years to 1.13 (95 percent CI, 1.01–1.25) at age 77 years.

On further analysis, exposure to neither 5-ASAs nor methotrexate produced a change in eGFR. On the other hand, azathioprine use led to a small increase in eGFR (0.32 mL/min/1.73 m², 95 percent CI, 0.16–0.48).

In light of the findings, the researchers recommended including intermittent monitoring of renal function in all patients with IBD as part of usual care. More studies are needed to prospectively identify mediators of the CKD–IBD association.