[en] [en] INTRODUCTION: The new European Kidney Function Consortium (EKFC) eGFR equation uses rescaled serum creatinine (SCr) to an age- and sex-specific normal median value, making it applicable across the entire age spectrum. We evaluated the performance of the recalibrated EKFCcrea equation using Indian-specific Q (for median SCr) and K (for normal glomerular filtration rate [GFR]) in a large Indian cohort and the ability to correctly classify chronic kidney disease (CKD).
METHODS: Indian adults (healthy and patients with CKD) were recruited. Plasma iohexol clearance was used to assess measured GFR (mGFR). Indian-specific Q values were derived from healthy individuals, and K from those under the age of 40 years. We evaluated EKFCcrea, CKD- Epidemiology Collaboration (EPI)2021, and recalibrated the EKFCcrea equations, incorporating the Indian Q (ISQ), Indian constant (ISK), and both (ISQ + ISK). We evaluated bias and accuracy (P30) for all equations.
RESULTS: A total of 1174 participants (615 healthy, 559 CKD), mean age 48 years, with equal sex distribution were recruited. The EKFCcrea equation showed a mean bias of 9.9 (95% CI: 8.7- 11.1) ml/min per 1.73 m2 with P30; 58.1%. EKFCISQ reduced bias to 4.9 (95% CI: 3.7 6.0) ml/min per 1.73 m2 and improved P30 to 64%. EKFCISK achieved a bias of -1.2 (95% CI: -0.1 to -2.2) ml/min per 1.73 m2 and P30 of 69%. 30%, 48%, and 67% of CKD patients were categorized into lower categories using the EKFCISQ, EKFCISK, and EKFCISQ+ISK equations, respectively, against the CKD-EPI 2021.
CONCLUSION: Recalibrating EKFCcrea with Indian-specific Q and K reduced bias and improved accuracy, with EKFCISK emerging as the best model. Adopting this recalibrated equation in clinical practice and public health initiatives after validation in diverse cohorts could lead to more accurate CKD diagnosis and staging in India.
Disciplines :
Urology & nephrology
Author, co-author :
Yadav, Ashok Kumar; Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Kaur, Jaskiran; Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Kaur, Rupinder; Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Agnihotri, Pratima; Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Prabhahar, Arun; Department of Nephrology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Ghosh, Arpita; The George Institute for Global Health, UNSW, New Delhi, India
Shafiq, Nusrat; Clinical Pharmacology Unit, Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Pal, Arnab; Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Kohli, Harbir Singh; Department of Nephrology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Thakur, Jarnail Singh; Department of Community Medicine and school of Public Health, Postgraduate Institute of Medical Education and Research, Chandigarh India
Parameswaran, Sreejith; Department of Nephrology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
Pottel, Hans ; Université de Liège - ULiège > Département des sciences cliniques ; Department of Public Health and Primary Care, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
Kumar, Vivek; Department of Nephrology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Delanaye, Pierre ; Université de Liège - ULiège > Département des sciences cliniques > Néphrologie ; Department of Nephrology-Dialysis-Apheresis, Hôpital Universitaire Carémeau, Université de Montpellier, Nîmes, France
Jha, Vivekanand; The George Institute for Global Health, UNSW, New Delhi, India ; School of Public Health, Imperial College, London, UK ; Manipal Academy of Higher Education, Manipal, Karnataka, India
Wellcome Trust/DBT India Alliance SERB - Science and Engineering Research Board Wellcome Trust ICMR - Indian Council of Medical Research
Funding text :
AKY has received grant from the Department of Biotechnology/Wellcome trust, India Alliance (IA/CPHI/19/1/ 504609) and the Indian Council of Medical Research, New Delhi, India (ICMR/04/779/IGP-2025); VJ has received grant from Department of Biotechnology, New Delhi, India (Grant No: BT/PR11105/MED/30/1345/2014); and VK has received grant from the Science and Engineering Research Board, New Delhi, India (EMR/2017/002159) to support this study. The Clinical Pharmacology Unit is supported by the Indian Council of Medical Research Network for Phase I studies (ICMR/BMS-Phase-1/CAR-2023). The funding agencies had no role in the study design, analysis, and interpretation of data.
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