Comparisons between the 2012 New CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) Equations and Other Four Approved Equations

Abstract

ObjectiveThe Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) reported two equations in 2012: one based on cystatin C concentration (CKD-EPI2012cys) and the other using both serum creatinine and cystatin C concentrations (CKD-EPI2012Scr-cys). We compared the adaptability of new formulae with other four equations.MethodsParticipants (n = 788; median age, 54 [range, 19–94] years) were recruited from the First Affiliated Hospital of Nanjing Medical University. The reference glomerular filtration rate (rGFR) was measured by a 99mTc-DTPA renal dynamic imaging method, and the estimated glomerular filtration rate (eGFR) was calculated separately by the Chinese adapted Modification of Diet in Renal Disease equation (C-MDRD), MacIsaac, Ma, serum creatinine-based CKD-EPI equation (CKD-EPI2009Scr), CKD-EPI2012cys and CKD-EPI2012Scr-cys equations. We compared the performance of six equations with rGFR.ResultsMedian rGFR was 76.35 (interquartile range, 59.03–92.50) mL/min/1.73 m2. Compared with CKD-EPI2009Scr, CKD-EPI2012Scr-cys formula had better diagnostic value with larger area under the receiver operating characteristic curve (ROCAUC, 0.879, p = 0.006), especially in young participants (ROCAUC, 0.883, p = 0.005). CKD-EPI2012cys equation did not perform better than other available equations. Accuracy (the proportion of eGFR within 30% of rGFR [P30]) of the CKD-EPI2012Scr-cys equation (77.03%) was inferior only to MacIsaac equation (80.2%) in the entire participants, but performed best in young participants with normal or mildly-injured GFR. Neither of the two new CKD-EPI equations achieved any ideal P30 in the elderly participants with moderately-severely injured GFR. Linear regression analysis demonstrated a consistent result. In this study, CKD-EPI2012Scr-cys had a relatively better diagnosis consistency of GFR stage between the eGFR and rGFR in the whole cohort.ConclusionCKD-EPI2012Scr-cys appeared less biased and more accurate in overall participants. Neither of the new CKD-EPI equations achieved ideal accuracy in senior participants with moderately-severely injured GFR. A large-scale study with more subjects and cooperating centers to develop new formulae for the elderly is assumed to be necessary.

Prevalence, awareness and treatment of chronic kidney disease among middle‐aged and elderly: The China Health and Retirement Longitudinal Study

“…In the former study, about one twentieth of the population aged 45 years or above were reported to have eGFR < 60 mL/min per 1.73 m 2 (based on a modified Modification of Diet in Renal Disease (MDRD) equation), and one fifth had CKD condition according to the Kidney Disease Outcome Quality Initiative (K/DIGO) criteria . It has been shown from two Chinese population studies, that eGFR estimated by creatinine and cystatin C was always significantly less than that by equation using creatinine only, especially for a measured eGFR of 30 to 89 mL/min per 1.73 m 2 , . The differences in those were less than our results, which may be due to the smaller means of the measured GFRs and the lower proportions in CKD stage 2 & 3 .…”

Application of creatinine- and/or cystatin C-based glomerular filtration rate estimation equations in&nbsp;elderly Chinese

“…In the original development and validation dataset, the CKD-EPIscr-cys equation performed better than equations based on either marker alone, but the CKD-EPIcys equation did not show obvious advantages over the CKD-EPIscr equation 21. Our previous study indicated that the CKD-EPIscr-cys equation achieved ideal accuracy in nonelderly individuals with normally or mildly injured GFR 29. Validation in the European elderly population suggested that the CKD-EPI equations performed as well in older people as in the younger population.…”

Estimating glomerular filtration rate by serum creatinine or/and cystatin C equations: An analysis of multi‐centre Chinese subjects

“…Yet, only limited data exist outside the development cohort regarding their application in Chinese individuals. In our previous study, CKD‐EPIscr‐cys achieved ideal performance in overall population while Mascr and Mascr‐cys equations appeared more biased and less accurate . Recently, we investigated the application of available equations in the Chinese elderly, of which Fengscr‐cys equation appeared to be optimal in this specific population .…”

“…In our previous study, CKD-EPIscr-cys achieved ideal performance in overall population while Mascr and Mascr-cys equations appeared more biased and less accurate. 23 Recently, we investigated the application of available equations in the Chinese elderly, of which Fengscr-cys equation appeared to be optimal in this specific population. 24 However, Guo et al suggested that the Fengscr-cys equation showed poorer performance for GFR estimation in Chinese adult CKD patients in comparison with the CKD-EPIscr-cys equation.…”