Kidney function estimation equations: a narrative review.

Area of Science:

• Nephrology
• Clinical Chemistry
• Biostatistics

Background:

• Glomerular filtration rate (GFR) is a key indicator of kidney health, essential for managing diseases and modifying drug dosages.
• Decreased kidney function correlates with increased mortality and disease progression.
• Measured GFR (mGFR) is accurate but not clinically feasible; estimated GFR (eGFR) is preferred for its practicality.

Purpose of the Study:

• To review available eGFR equations and their clinical applications in various patient populations.
• To compare the accuracy and limitations of different eGFR formulas.
• To highlight the importance of selecting appropriate eGFR equations for specific clinical scenarios.

Main Methods:

• Systematic review of existing eGFR equations.
• Analysis of equations utilizing serum creatinine and/or cystatin C levels.
• Evaluation of equation performance in normal and chronic kidney disease (CKD) patients.

Main Results:

• Multiple eGFR equations exist, posing challenges for clinical use due to differing population applications.
• The CKD-EPI equation is highly recommended for its robustness and accuracy across diverse populations.
• The study discusses the strengths and limitations of various eGFR equations.

Conclusions:

• Selecting the correct eGFR equation is critical for accurate kidney function assessment and patient care.
• The CKD-EPI equation demonstrates superior performance in most populations.
• Further regional validation studies are needed to ensure global applicability of eGFR equations, accounting for population variations.