A multicentre cross-sectional study of 15,879 adults in the UK compared five creatinine-based eGFR equations against measured GFR. The Lund-Malmö Revised (LMR) and EKFC equations demonstrated the highest accuracy and least bias, particularly in South Asian, young, and low-BMI populations. Using outdated equations could inappropriately exclude 29% to 52% of eligible patients from SGLT2 inhibitor therapy based on GFR thresholds. Adopting these validated equations in routine practice could improve CKD staging and ensure appropriate cardiorenal pharmacotherapy.
Accurate assessment of kidney function using estimated glomerular filtration rate (eGFR) is fundamental for chronic kidney disease diagnosis and management, although performance is variable in African and Asian cohorts. We evaluated creatinine-based eGFR performance in an ethnically diverse United Kingdom cohort.
We conducted a multi-centre, cross-sectional study. We included adults who had paired measured GFR (mGFR) and serum creatinine tests between 2009 and 2022. eGFR was calculated using five validated creatinine-based equations. The primary outcome was eGFR agreement with mGFR determined by assessing correlation, difference, precision and 30% accuracy (P30) with stratification by ethnicity.
The study included 15,879 participants (mean age 54 ± 16 years; 8893/15,879 (56%) male). On average, all equations overestimated mGFR. There were significant variations in difference (p < 0.001) and accuracy (p < 0.001) between all equations. Lund-Malmo Revised (LMR) had the least difference (1.4 mL/min/1.73 m2; 95% CI: 1.1-1.6 mL/min/1.73 m2) and highest accuracy (P30: 86.0%; 95% CI: 85.5-86.6%), followed by European Kidney Function Consortium (EKFC).eGFR had the greatest difference and lowest accuracy in South Asians, compared with other ethnicity groups. mGFR was substantially overestimated in young adults (<25 years), low BMI (<20 kg/m2) and hypoalbuminaemia (<20 g/L). Hypothetical prescribing analyses for dapagliflozin (upper GFR threshold: 75 mL/min/1.73 m2) showed potential prescribing ineligibility based on eGFR alone in 29% (1933/6586) to 52% (3433/6586) of eligible participants.
LMR and EKFC showed improved agreement with mGFR, particularly in South Asians and young adults. Further prospective validation is recommended to support changes in clinical practice. FUNDING: Kidney Research UK.
