Performance of Estimated Kidney Function Equations for Predicting Aminoglycosides Clearance in Thai Population

Disparities in the performance of various kidney function equations in predicting aminoglycoside clearance (CL) have been identified. However, data specific to the Thai population remains limited. This study aimed to evaluate the performance of kidney function equations in estimating aminoglycoside CL in Thai patients. Data were retrospectively collected from hospitalized Thai patients who received amikacin or gentamicin over a 10-year period. Population pharmacokinetic (PK) analysis was performed using a nonlinear mixed-effects modeling approach. The association between aminoglycoside CL and kidney function, estimated by various equations, was ranked based on the magnitude of change in the Akaike Information Criterion (AIC) relative to the base model. A total of 138 adult Thai patients treated with either gentamicin (66%) or amikacin (34%) were enrolled. The non-body surface area (BSA)-indexed estimated glomerular filtration rate (eGFR) equations showed a stronger association with aminoglycoside CL compared to the 1.73 m² BSA-indexed equations. The non-BSA-indexed 2021 Chronic Kidney Disease Epidemiology Collaboration eGFR (2021 CKD-EPI eGFRcr) equation demonstrated the highest association with aminoglycoside CL. The estimated volume of distribution (V) and CL from the final model were 21.91 L and 2.62 L/h, respectively. Among the Thai population, the non-BSA-indexed 2021 CKD-EPI eGFRcr equation of the non-race demonstrated the highest performance in estimating aminoglycoside CL. Further studies are warranted to confirm these findings with other renally eliminated drugs.