Comparison of Predictability of Future Cardiovascular Events Between Chronic Kidney Disease (CKD) Stage Based on CKD Epidemiology Collaboration Equation and That Based on Modification of Diet in Renal Disease Equation in the Japanese General Population

– Iwate KENCO Study –

Abstract

Background: Whether estimated glomerular filtration rate (eGFR) calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) Study equation (eGFR_CKDEPI) improves risk prediction compared to that calculated using the Modification of Diet in Renal Disease (MDRD) study equation (eGFR_MDRD) has not been examined in a prospective study in Japanese people. Methods and Results: Participants (n=24,560) were divided into 4 stages (1, ≥90; 2, 60–89 (reference); 3a, 45–59; 3b+ <45ml·min^–1·1.73m^–2) according to eGFR_CKDEPI or eGFR_MDRD. Endpoints were all-cause death, myocardial infarction (MI) and stroke. Area under the receiver operating characteristic curves (95% confidence intervals) for predicting all-cause death, MI and stroke by eGFR_CKDEPI vs. eGFR_MDRD were 0.680 (0.662–0.697) vs. 0.582 (0.562–0.602); 0.718 (0.665–0.771) vs. 0.642 (0.581–0.703); and 0.656 (0.636–0.676) vs. 0.576 (0.553–0.599), respectively. Multivariate-adjusted Cox regression and Poisson regression analysis results were similar for adjusted incidence rates and adjusted hazard ratios in each corresponding stage between the 2 models and no differences were found in model assessment parameters. Net reclassification improvement (NRI) for predicting all-cause death, MI and stroke were estimated to be 6.7% (P<0.001), –1.89% (P=0.029) and –0.20% (P=0.421), respectively. Conclusions: Better discrimination was achieved using eGFR_CKDEPI than eGFR_MDRD on univariate analysis. NRI analysis indicated that the use of eGFR_CKDEPI instead of eGFR_MDRD offered a significant improvement in reclassification of death risk.  (Circ J 2013; 77: 1315–1325)