2026 Volume 52 Issue 5 Pages 241-252
The guidelines for TDM of vancomycin were updated in 2022, with area under the curve (AUC)-guided dosing more strongly recommended than conventional trough-guided dosing to reduce the risk of vancomycin-associated nephrotoxicity. Although previous studies have demonstrated the usefulness of AUC calculated from trough-only data (one-point AUC-guided dosing), only a limited number of reports have focused exclusively on elderly patients. In this study, we compared the incidence of nephrotoxicity between one-point AUC-guided and trough-guided dosing in elderly patients aged 75 years at a single center. There were 257 trough-guided dosing cases and 223 one-point AUC-guided dosing cases. Tendency scores were calculated using nephrotoxicity risk factors, hemoglobin level, vancomycin dose, and Bayesian-estimated half-life as covariates, and matching was performed, resulting in the selection of 128 subjects in each group. The initial and subsequent trough concentrations were used to evaluate the AUC and AKI in the early and maintenance phases, respectively. An estimated AUC > 600 µg·h/mL was defined as the evaluation indicator in the maintenance phase, and the proportion of patients exceeding this threshold was markedly lower in the one-point AUC-guided dosing than in the trough-guided dosing (26.6％ vs. 12.5％, P = 0.007). Compared with trough-guided dosing, one-point AUC-guided dosing substantially prolonged the time to AKI onset during the maintenance phase (HR 0.34 [95％CI: 0.13 – 0.87], P = 0.024). In conclusion, one-point AUC-guided dosing may be useful in preventing nephrotoxicity during the maintenance phase in patients aged 75 years.
