Peak measurement for vancomycin AUC estimation in obese adults improves precision and lowers bias

Abstract

Vancomycin area under the curve (AUC) estimates may be skewed in obese adults due to weight-dependent pharmacokinetic parameters. We demonstrate that peak and trough measurements reduce bias and improve the precision of vancomycin AUC estimates in obese adults (n = 75) and validate this in an independent cohort (n = 31). The precision and mean percent bias of Bayesian vancomycin AUC estimates are comparable between covariate-dependent (R2 = 0.774, 3.55%) and covariate-independent (R2 = 0.804, 3.28%) models when peaks and troughs are measured but not when measurements are restricted to troughs only (R2 = 0.557, 15.5%).