The effect of the body mass index and creatinine clearance on serum trough concentration of vancomycin in adult patients

Abstract

Background: The aim of this study was to evaluate the influence of patient body mass index (BMI) and estimated creatinine clearance (CrCl) on serum vancomycin concentrations in order to define a possible optimal dosage regimen in overweight patients from data obtained during therapeutic drug monitoring.Methods: This retrospective study used data collected from January 2017 to January 2019. Adult patients (n=204) receiving vancomycin treatment at a dose of 1000 mg in every 12 h and undergoing serum monitoring. Data collected included patient gender, age, height and weight, vancomycin regimens and concentrations, and serum creatinine. In this study, statistical comparisons were made on the results from patients according to serum vancomycin concentration.Results: Serum vancomycin concentration was significantly related to BMI (P < 0.001) and CrCl (P < 0.05) in adult patients. Further, the trough serum vancomycin concentration showed a logarithmic correlation with BMI (R = -0.5108, 95 % CI: -0.6082 to -0.3982, P < 0.001) and CrCl (R = -0.5739, 95 % CI: -0.6616 to -0.4707, P < 0.001). In addition, the CrCl was significantly related to BMI (P < 0.01). Besides, some of the patients with higher BMI (≥ 24 kg/m2) met the goal trough concentration after an adjustment from 1000 mg every 12 h to 1000 mg every 8 h.Conclusions: Serum vancomycin concentration decreases progressively with increasing BMI due to the augment in CrCl in adult patients. Therefore, dose adjustment should be based on BMI and CrCl for safe and effective use of vancomycin in adult patients (BMI ≥ 24 kg/m2).