Frequency and risk factors of renal insufficiency in inflammatory bowel disease inpatients

Renal involvement in patients with inflammatory bowel disease (IBD) has been well documented. However, there was a paucity of data on the frequency of renal insufficiency and its risk factors in this patient population. The aim of the study was to determine the frequency and factors associated with renal insufficiency within IBD inpatients.

This case-control study was conducted on both Crohn's disease and ulcerative colitis inpatients in our tertiary care center from 2009 to 2010. Patients were identified as having renal insufficiency by the criterion of glomerular filtration rate < 60 mL/min/1.73 m. The glomerular filtration rate was further assessed against normal reference ranges. Risk factors for renal insufficiency were evaluated by univariable and multivariable analyses.

A total of 251 eligible patients were included. The frequency of renal insufficiency was 15.9% (95% confidence interval: 11.4-20.5), with 40 patients having a glomerular filtration rate <60 mL/min/1.73 m. Univariable analysis demonstrated several possible risk factors, including older age at admission (42.0 ± 16.2 years versus 57.6 ± 13.3 years, P < 0.001), and a longer median duration of IBD (9.0 years [interquartile range: 3.5-20.0] versus 25.0 years [interquartile range: 15.0-36.0], P < 0.001). The multivariable logistic analysis demonstrated that for every 5-year increase in age at the time of admission, the likelihood of having renal insufficiency increased by 30%.

Acute or chronic renal sufficiency in IBD inpatients was common, especially in elderly. Acute renal insufficiency can be medically reversed if properly treated. We recommend that renal function be closely monitored in IBD inpatients.