New and old GFR equations: a European perspective

Abstract

Glomerular filtration rate (GFR) is estimated in clinical practice from equations based on the serum concentration of endogenous biomarkers and demographic data. The 2009 creatinine-based CKD-EPI equation (CKD-EPI2009) was worldwide recommended until 2021, when it was recalibrated to remove the African-American race factor. The CKD-EPI2009 and CKD-EPIcr2021 equations overestimates GFR of adults aged 18 to 30 years, with a strong overestimation in eGFR at age 18. CKD-EPICr2021 does not perform better than CKD-EPI2009 in US population, overestimating GFR in non-black subjects, and underestimating it in black subjects with the same magnitude. CKD-EPICr2021 performed worse than the CKD-EPI2009 in White Europeans, and provides no or limited performance gains in Black European and Black African populations. The EKFC equation, which incorporates median normal value of serum creatinine in healthy population overcomes the limitations of the CKD-EPI equations: it provides a continuity of eGFR at the transition between pediatric and adult care, and performs reasonably well in diverse populations, assuming dedicated scaling of serum creatinine (Q) values is used. The new EKFC equation based on cystatin C (EKFCCC) shares the same mathematical construction, namely, it incorporates the median cystatin C value in the general population, which is independent of sex and ethnicity. EKFCCC is therefore a sex free and race free equation, which performs better than the CKD-EPI equation based on cystatin C. Despite advances in the field of GFR estimation, no equation is perfectly accurate, and GFR measurement by exogenous tracer clearance is still required in specific populations and/or specific clinical situations.

Reduced Systemic Microvascular Function in Patients With Resistant Hypertension and Microalbuminuria: an Observational Study

“…As expected, the prevalence of chronic kidney disease was greater in the RH + MAU group, as classi ed according to the creatinine-based Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI 2009 ) (52). In this case, an estimated glomerular ltration rate (eGFR) < 60 mL/min/1.73 m 2 is considered to represent mild renal insu ciency for both men and women.…”

Biomedical Evaluation of Early Chronic Kidney Disease in the Air Force: Building a Predictive Model from the Taiwan Military Health Service

“…The CKD Epidemiology Collaboration (CKD-EPI) equation was developed in an effort to create a more precise formula for eGFR, especially if the actual GFR is more than 60 mL/min per 1.73 m 2 [ 26 , 27 ]. Since the aMDRD formula for calculating GFR currently used in Taiwan is based on a Western population, this study suggests that in subsequent studies to validate the formula for assessing renal function, risk factors that are more suitable for the Taiwanese population should be added to establish a local formula that is more compatible with this population.…”

Role of Estimated Glomerular Filtration Rate in Clinical Research: The Never-Ending Matter

“…On the other hand, testing the efficacy of nephroprotection at an early stage of CKD is the main aim of clinical research. The role of eGFR for clinical and research purposes has been already developed in several review articles as reported in Table 1 [ 9 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 ], whereas the main contents and novelties of the present review are repored in Table 2 (Ref. [ 6 , 60 , 62 , 63 , 64 , 68 ]).…”