Renal assessment using CKD-EPI equation is useful as an early predictor of contrast- induced nephropathy in elderly patients with cancer.

OBJECTIVES: To assess respective roles of serum creatinine (SCr) alone and estimated glomerular filtration rate (eGFR) as an early predictor for contrast-induced nephropathy (CIN) in elderly patients with cancer.

MATERIALS AND METHODS: eGFR of 348 patients at 65years or older with malignancy who underwent contrast-enhanced computed tomography (CECT) were calculated. eGFR was calculated based on the following three equations: Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI); Modification of Diet in Renal Disease Study (MDRD); Cockcroft-Gault (CG). CIN was subdivided into two groups: CIN25% (SCr increase >25% but ≤0.5mg/dl), and CIN0.5 (SCr increase >0.5mg/dl). The occurrence and clinical outcomes of CIN were determined according to SCr and eGFR.

RESULTS: After CECT, CIN occurred in 50 (14.4%) patients, including 33 CIN25% patients and 17 CIN0.5 patients. CIN0.5 was significantly correlated with prolonged hospitalizations and increased in-hospital mortality, but not CIN25% . Despite SCr<1.5mg/dl, preexisting renal insufficiency (RI) was observed in 47 (13.5%) patients based on CKD-EPI equation, 50 (14.4%) patients based on MDRD equation, and 144 (41.4%) patients based on CG formula. In preexisting RI, the prevalence of CIN0.5 had an odds ratio of 15.02 (5.24 to 43.07) based on CKD-EPI equation, 13.73 (4.81 to 39.20) based on MDRD equation, and 5.03 (1.60 to 15.75) based on CG formula.

CONCLUSION: In elderly patients with cancer who visit the emergency department, renal assessment before CECT using CKD-EPI equation was superior to SCr alone, MDRD equation, or CG formula in predicting the occurrence of CIN related CECT.