Can different formulae be used in the diagnosis and staging of chronic kidney disease?

Objectives: Chronic kidney disease (CKD), which has a significant prevalence of 15.7 % in Turkey, is a global health problem that particularly affects elderly. It is difficult to distinguish between age-related and CKD-related declines in kidney function with current glomerular filtration rate (GFR) estimation methods. The “HUGE” formula, incorporating haematocrit, urea, and gender, offers improved differentiation, targeting individuals over 40. This study aims to evaluate the effectiveness of the HUGE formula in estimating GFR in this demographic group and to establish a better diagnostic threshold. Methods: A retrospective study of 500 participants over 40 years was conducted and divided into CKD (252) and non-CKD (248) based on demographics, laboratory tests and ultrasound evaluation. Renal function was classified by the HUGE equation (HUGE<0 for age-related decline; ≥ 0 for CKD) and GFR estimates were compared with KDIGO guidelines via CKD-EPI, FAS and BIS1. Results: We observed significant discrepancies in estimated glomerular filtration rate (eGFR) and its staging among different formulas. The HUGE formula showed better agreement with eGFR staging after the cut-off point was set as “−1.58” and improved diagnostic accuracy, especially in stages 3a and 3b. Conclusions: The study validates the HUGE formula improved accuracy in diagnosing CKD, especially for stages 3a and 3b, with a new cut-off value of “−1.58”. It supports the inclusion of the HUGE formula into current diagnostic practices to improve the identification and staging of CKD in individuals over the age of 40, while also demonstrating the necessity for further clinical evaluations.