IBD patients may be at higher risk for CKD

A Swedish study found that 11.8% of patients with inflammatory bowel disease (IBD) were diagnosed with chronic kidney disease (CKD) within 10 years, and their risks of acute kidney injury and kidney stones were also elevated.

Patients with inflammatory bowel disease (IBD) were at higher risk for developing chronic kidney disease (CKD) over time, a recent study found.

Researchers in Sweden used data from the Stockholm Creatinine Measurements project to analyze the association between developing IBD and risks of diagnoses of CKD, acute kidney injury (AKI), or kidney stones, as well as clinically relevant decline in estimated glomerular filtration rate (eGFR). To determine relative risks, the primary cohort included all patients who had serum or plasma creatinine testing done at least once in primary care, and new IBD cases that occurred after the first recorded creatinine test were identified. Five- and 10-year absolute risks were determined in a secondary cohort of IBD cases and random controls matched in a one-to-five ratio for sex, age, and eGFR. The study's primary outcomes were CKD progression and CKD diagnosis. The study results were published Aug. 10 by the American Journal of Gastroenterology.

A total of 1,682,795 patients were included in the primary cohort study from 2006 to 2019. Mean age was 46 years, mean eGFR was 93 mL/min/1.73 m2, and 53% were women. Over a median of nine years of follow-up, 10,117 patients developed IBD: 3,519 Crohn's disease, 5,140 ulcerative colitis, and 1,458 unclassified disease. The primary cohort had 96,540 CKD progression events and 57,127 registered CKD diagnoses during follow-up. Periods of incident IBD were associated with higher risks of kidney-related complications than periods without IBD, with adjusted hazard ratios (HRs) of 1.19 (95% CI, 1.05 to 1.34) for CKD diagnosis, 1.10 (95% CI, 0.99 to 1.22) for CKD progression, and 1.22 (95% CI, 1.12 to 1.33) for a composite of both. In the secondary cohort, 6.4% (95% CI, 5.7% to 7.2%) and 11.8% (95% CI, 10.9% to 12.9%) of IBD cases developed CKD within five and 10 years, respectively. Patients with IBD were also at higher risk for AKI (adjusted HR, 1.86 [95% CI, 1.60 to 2.16]; 10-y absolute risk, 3.6%) and kidney stones (adjusted HR, 1.66 [95% CI, 1.46 to 1.90]; 10-y absolute risk, 5.6%).

The researchers noted that they had no data on patients' body mass index, blood pressure, or lifestyle factors and could not account for over-the-counter use of NSAIDs, among other limitations. “To conclude, about one in ten persons with IBD develop CKD within 10 years from diagnosis, bringing attention to a problem of potentially larger dimensions than traditionally believed,” they wrote. “This, together with higher observed risks of AKI emphasizes the need of established protocols for kidney function monitoring and referral to nephrological care.”