CKD-EPI versus Cockcroft-Gault formula for predicting contrast-induced nephropathy following percutaneous coronary intervention in patients without significant renal impairment.

INTRODUCTION: Individuals with glomerular filtration rate (GFR) ≥60 ml/min/1.73 m2 estimated by the Cockcroft-Gault formula (CG) who undergo percutaneous coronary intervention (PCI) frequently develop contrast-induced nephropathy (CIN). This study aimed to assess whether individuals with significant renal impairment assessed by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula, but not by CG, more often develop CIN following PCI than those without renal impairment by either formula.

METHODS: In this cross-sectional study analyzing patients with baseline CG GFR ≥60 ml/min/1.73 m2 before PCI, subjects were divided into two groups according to CIN occurrence. Baseline CKD-EPI GFR was calculated for all patients.

RESULTS: We analyzed 140 patients. Baseline GFR was 87.5±21.3 and 77.1±15.0 ml/min/1.73 m2 for CG and CKD-EPI, respectively. CIN occurred in 84.6% of individuals with baseline CKD-EPI GFR <60 ml/min/1.73 m2 vs. 51.1% of those without. Males and those with higher body mass index were more likely to present baseline CKD-EPI GFR <60 ml/min/1.73 m2 (p=0.021). Non-ionic contrast agent use and baseline CKD-EPI GFR ≥60 ml/min/1.73 m2 were protective factors against CIN. Greater amounts of contrast agent and acute coronary syndrome were associated with higher CIN risk. In subjects with serum creatinine <1.0 mg/dl, GFR was more likely to be overestimated by CG, but not by CKD-EPI (sensitivity 100.0%; specificity 52.0%).

CONCLUSION: In patients undergoing PCI without renal dysfunction by CG, a finding of CKD-EPI GFR <60 ml/ min/1.73 m2 was associated with a higher probability of CIN, especially among men and those with higher body mass index.