Assessment of the 2023 European Kidney Function Consortium (EKFC) equations in a Chinese adult population.

Objectives: The European Kidney Function Consortium (EKFC) developed two novel equations in 2023 for estimating glomerular filtration rate (GFR): one sex-free cystatin C-based equation (EKFC _Cys ) and one creatinine-cystatin C combined equation (EKFC _Cr-Cys ). This study compared their performance with the previous creatinine-based EKFC equation (EKFC _Cr ) and commonly used Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Berlin Initiative Study (BIS) equations in Chinese adults.
Methods: A total of 2,438 Chinese adults (mean age=53.04 years) who underwent the 99mTc-DTPA renal dynamic imaging for reference GFR (rGFR) were included. Diagnostic value was evaluated using correlation coefficients, sensitivity, specificity, and area under the receiver operating characteristic curve (ROC ^AUC ). Performance was assessed in terms of bias, precision (interquartile range of the median difference [IQR]), accuracy (percentage of estimates ±30 % of rGFR [P30], and root-mean-square error [RMSE]) across age, sex, and rGFR subgroups. Gender differences in bias and P30 were also analyzed.
Results: Average rGFR was 73.37 mL/min/1.73 m ² . EKFC equations showed stronger correlations and larger AUCs compared to the parallel CKD-EPI equations, with EKFC _Cr-Cys demonstrating the greatest improvement (R=0.771, ROC ^AUC =0.913). Concerning bias, precision, and accuracy, EKFC equations consistently outperformed CKD-EPI equations. EKFC _Cr-Cys and EKFC _Cr performed acceptably well in the entire population and were equivalent to BIS equations in the elderly. All equations, including EKFC _Cys , showed similar P30 accuracy across sexes.
Conclusions: EKFC equations provided a reasonable alternative for estimating GFR in the Chinese adult population. While EKFC _Cys did not outperform EKFC _Cr , EKFC _Cr-Cys improved the accuracy of single-marker equations.
(© 2024 Walter de Gruyter GmbH, Berlin/Boston.)