# Impact of switching from the CKD-EPI2009 to the EKFC equation on the epidemiology of chronic kidney disease and nephrology workload

## TL;DR

Switching from the CKD-EPI2009 to the EKFC equation increases the estimated prevalence of chronic kidney disease, especially in older adults, potentially affecting healthcare resources.

## Contribution

The study quantifies the impact of adopting the EKFC equation on CKD prevalence and nephrology workload in a real-world population.

## Key findings

- Switching to EKFC increased CKD G3-G5 prevalence by 39.6% in the general population and 41.8% in those aged ≥65 years.
- Among patients with albuminuria assessments, EKFC identified 36.3% with CKD G1-G5 compared to 32.5% with CKD-EPI2009.
- Adopting EKFC could require additional nephrologists in Madrid to manage newly diagnosed CKD patients.

## Abstract

Chronic kidney disease (CKD) can be diagnosed by estimating the glomerular filtration rate (eGFR) using serum creatinine-based equations, mainly CKD-EPI2009. The European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) recently supported adopting the European Kidney Function Consortium (EKFC) equation.

We compared eGFR values obtained using CKD-EPI2009 and EKFC in analytical records from a single laboratory corresponding to 216 637 individual adults receiving primary and specialized healthcare in 2023 in a catchment area in Madrid (Spain).

Switching from CKD-EPI2009 to EKFC resulted in a 39.6% higher prevalence of low eGFR consistent with CKD G3-G5 (13.4% vs 9.6% in the full population and 36.3% vs 25.6% among people aged ≥65 years). Among 33 789 patients with albuminuria assessments, the prevalence of eGFR and albuminuria values consistent with CKD G1-G5 was 36.3% for EKFC and 32.5% for CKD-EPI2009. Among newly identified patients with potential CKD G3–G5, 25% had A2–A3 albuminuria. Differences in CKD prevalence between both equations were observed for men and women. According to National guidelines, in the first year after the switch, 0.33 to 0.58 full-time nephrologist equivalents would be needed to care for newly diagnosed patients with CKD in this catchment area, potentially resulting in between five and nine nephrologists needed for the Madrid region.

In this retrospective analysis, a switch from the creatinine-based CKD-EPI2009 to the EKFC eGFR equation would increase the prevalence of CKD, especially among the elderly. EKFC may identify patients with A2–A3 albuminuria as having CKD that may have been missed by CKD-EPI2009 in healthcare systems with low uptake of albuminuria assessments.