Incidence of Acute Kidney Injury in Trough and AUC/MIC Vancomycin Dosing Strategies in a Large Tertiary Care Center: A Retrospective Cohort

Acute kidney injury (AKI) is a complication associated with vancomycin use. There is evidence that this was related to the presence of supratherapeutic vancomycin levels rather than the drug itself. The area under the curve over 24 h to minimum inhibitory concentration (AUC/MIC) dosing for vancomycin has replaced trough-based dosing, but the impact of this change on AKI rates remains unclear. A retrospective cohort study was conducted in a tertiary care teaching hospital. Patients from the trough cohort were recruited from January 1, 2019, to June 30, 2019, and the AUC/MIC cohort from July 1, 2021, to January 1, 2022. Sociodemographics, clinical characteristics, and concomitant medications were obtained. AKI was defined by The Kidney Disease Improving Global Outcomes. A total of 1056 patients were included, 509 in the trough cohort and 547 in the AUC/MIC cohort. The baseline rates of chronic kidney disease were 15.4% and 9.9%, respectively. The AKI rates were 15.9% and 11.9% for trough and AUC/MIC cohorts, respectively (P-value .045). The most frequent nephrotoxins were piperacillin/tazobactam (TZP), diuretics, and IV contrast for both groups. The rates of supratherapeutic levels were higher in the trough cohort (20.7%) than in the AUC/MIC cohort (6.6%). The multivariate logistic regression analysis showed that trough dosing was not associated with increased rates of AKI (OR = 0.96 CI 0.64-1.44). Supratherapeutic levels (OR = 4.64), diuretics (OR = 1.62), TZP (OR = 2.01), and ICU admission (OR = 1.72) were associated with AKI. Vancomycin AUC/MIC dosing strategy was associated with decreased rates of supratherapeutic levels of this drug compared to trough dosing, with a trend toward lower rates of AKI.