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

  • Yi Chen , Yao Ma , Zhenzhu Yong , Lu Wei , Xiaohua Pei , Bei Zhu EMAIL logo and Weihong Zhao EMAIL logo
Published/Copyright: February 12, 2024
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Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 62 Issue 8

Abstract

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 (EKFCCys) and one creatinine-cystatin C combined equation (EKFCCr-Cys). This study compared their performance with the previous creatinine-based EKFC equation (EKFCCr) 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 (ROCAUC). 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 m2. EKFC equations showed stronger correlations and larger AUCs compared to the parallel CKD-EPI equations, with EKFCCr-Cys demonstrating the greatest improvement (R=0.771, ROCAUC=0.913). Concerning bias, precision, and accuracy, EKFC equations consistently outperformed CKD-EPI equations. EKFCCr-Cys and EKFCCr performed acceptably well in the entire population and were equivalent to BIS equations in the elderly. All equations, including EKFCCys, showed similar P30 accuracy across sexes.

Conclusions

EKFC equations provided a reasonable alternative for estimating GFR in the Chinese adult population. While EKFCCys did not outperform EKFCCr, EKFCCr-Cys improved the accuracy of single-marker equations.

Keywords: estimating equations; glomerular filtration rate (GFR); kidney function; sex
Corresponding author: Bei Zhu, MD, and Weihong Zhao, MD, PhD, Division of Nephrology, Department of Geriatrics, Jiangsu Province Hospital and Nanjing Medical University First Affiliated Hospital, Nanjing, P.R. China, E-mail: (B. Zhu), (W. Zhao)
Yi Chen and Yao Ma contributed equally to this work. Bei Zhu and Weihong Zhao share senior authorship.

Funding source: National Key Research and Development Program of China - Key Special Project on Science and Technology

Award Identifier / Grant number: (2023YFC3605500)

Funding source: National Key Research and Development Program of China

Award Identifier / Grant number: (2018YFC2002100, 2018YFC2002102)

Funding source: National Natural Science Foundation of China

Award Identifier / Grant number: (82171585, 81971320)

Funding source: Jiangsu Province Older Adults Health Introduction New Technique Project

Award Identifier / Grant number: (LX2021003)

Funding source: Jiangsu Province Hospital Clinical Ability Improvement Project

Award Identifier / Grant number: (JSPH-MC-2022-22)

  1. Research ethics: This study was approved by the Ethics Committee of the First Affiliated Hospital of Nanjing Medical University and conducted in accordance with the Declaration of Helsinki, registration number 2021-SR-508.

  2. Informed consent: Informed consent was obtained from all individuals included in this study.

  3. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  4. Competing interests: Authors state no conflict of interest.

  5. Research funding: This study was supported by the grants from the National Key Research and Development Program of China - Key Special Project on Science and Technology Responses to Proactive Health and Population Aging (2023YFC3605500), the National Key Research and Development Program of China (2018YFC2002100, 2018YFC2002102), National Natural Science Foundation of China (82171585, 81971320), Jiangsu Province Older Adults Health Introduction New Technique Project (LX2021003), Jiangsu Province Hospital Clinical Ability Improvement Project (JSPH-MC-2022-22).

  6. Data availability: The data underlying this article will be shared on reasonable request to the corresponding author.

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Supplementary Material

This article contains supplementary material (https://doi.org/10.1515/cclm-2024-0080).

Received: 2023-07-25
Accepted: 2024-01-23
Published Online: 2024-02-12
Published in Print: 2024-07-26

© 2024 Walter de Gruyter GmbH, Berlin/Boston

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https://doi.org/10.1515/cclm-2024-0080
Keywords for this article
estimating equations; glomerular filtration rate (GFR); kidney function; sex

Articles in the same Issue

  1. Frontmatter
  2. Editorial
  3. Analytical performance specifications – moving from models to practical recommendations
  4. Opinion Papers
  5. What the Milan conference has taught us about analytical performance specification model definition and measurand allocation
  6. The role of analytical performance specifications in international guidelines and standards dealing with metrological traceability in laboratory medicine
  7. How clinical laboratories select and use Analytical Performance Specifications (APS) in Italy
  8. Outcome-based analytical performance specifications: current status and future challenges
  9. Analytical performance specifications based on biological variation data – considerations, strengths and limitations
  10. State-of-the-art model for derivation of analytical performance specifications: how to define the highest level of analytical performance technically achievable
  11. Analytical performance specifications for combined uncertainty budget in the implementation of metrological traceability
  12. When bias becomes part of imprecision: how to use analytical performance specifications to determine acceptability of lot-lot variation and other sources of possibly unacceptable bias
  13. Using analytical performance specifications in a medical laboratory
  14. Issues in assessing analytical performance specifications in healthcare systems assembling multiple laboratories and measuring systems
  15. Applying the Milan models to setting analytical performance specifications – considering all the information
  16. Guidelines and Recommendations
  17. Recommendations for blood sampling in emergency departments from the European Society for Emergency Medicine (EUSEM), European Society for Emergency Nursing (EuSEN), and European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group for the Preanalytical Phase. Executive summary
  18. General Clinical Chemistry and Laboratory Medicine
  19. Assessment of accuracy of laboratory testing results, relative to peer group consensus values in external quality control, by bivariate z-score analysis: the example of D-Dimer
  20. The stability of 65 biochemistry analytes in plasma, serum, and whole blood
  21. Assessment of the 2023 European Kidney Function Consortium (EKFC) equations in a Chinese adult population
  22. In vitro, in vivo metabolism and quantification of the novel synthetic opioid N-piperidinyl etonitazene (etonitazepipne)
  23. Quantification of blood glial fibrillary acidic protein using a second-generation microfluidic assay. Validation and comparative analysis with two established assays
  24. Association of prehospital lactate levels with base excess in various emergencies – a retrospective study
  25. Reference Values and Biological Variations
  26. Stability of ten serum tumor markers after one year of storage at −18°C
  27. Variations in tumor growth, intra-individual biological variability, and the interpretation of changes
  28. Cancer Diagnostics
  29. N-linked glycosylation of the M-protein variable region: glycoproteogenomics reveals a new layer of personalized complexity in multiple myeloma
  30. Cardiovascular Diseases
  31. Reference intervals for high sensitivity cardiac troponin I and N-terminal pro-B-type natriuretic peptide in children and adolescents on the Siemens Atellica
  32. Infectious Diseases
  33. Fetal chronic hypoxia does not affect urinary presepsin levels in newborns at birth
  34. Letters to the Editor
  35. AWMF statement on medical services in laboratory diagnostics and pathology with regard to the IVDR
  36. An outline of measurement uncertainty of total protein in urine estimated according to the ISO Technical Specification 20914
  37. Early diagnosis of severe illness in an outpatient – the Sysmex XN’s neutrophil reactivity parameter
  38. Analytical and diagnostic performance of Theradiag i-Tracker assays on IDS-iSYS for infliximab and adalimumab therapeutic drug monitoring
  39. Improving the diagnosis of AATD with aid of serum protein electrophoresis: a prospective, multicentre, validation study
  40. Cerebrospinal fluid kappa free light chains in patients with tumefactive demyelination
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