Vancomycin-associated acute kidney injury and its clinical and economic impact: a retrospective cohort study using two Japanese healthcare databases

Abstract

Background

Previous studies examining vancomycin-associated acute kidney injury (AKI) were methodologically limited. We herein investigated the AKI incidence, clinical outcomes, and economic impact of this condition on Japan's aging population using a robust, methodological approach to analyze information from two, large-scale, Japanese, healthcare databases.

Methods

This retrospective cohort study analyzed data on 2007 and 2607 patients aged ≥18 years and registered with the Medical Data Vision (MDV) database and the JMDC, Inc. database, respectively, who received vancomycin ≥4 days. Target trial emulation was employed with 1:1 propensity score matching to compare the outcomes of patients with and without AKI. The primary outcomes included 30-day in-hospital mortality, length of hospital stay (LOS), and direct medical costs. The KDIGO guidelines’ definition of AKI was used.

Results

AKI occurred in 19.4 % (MDV) and 14.9 % (JMDC) of the cohorts with the median onset being five days. After propensity score matching (386 and 387 pairs for MDV and JMDC, respectively), the AKI group demonstrated significantly higher 30-day in-hospital mortality (odds ratio: 3.82 [95 % confidence interval (CI): 2.52–5.79] for MDV; 4.36 [95 % CI: 2.89–6.57] for JMDC; both P < .001), prolonged LOS (hazard ratio: 1.45 [95 % CI: 1.22–1.72] for MDV; 1.79 [95 % CI: 1.35–2.37] for JMDC; both P < .001), and higher daily direct medical costs per patient (cost ratio: 1.39 [95 % CI: 1.19–1.62] for MDV; 1.33 [95 % CI: 1.18–1.50] for JMDC; both P < .001).

Conclusions

Vancomycin-associated AKI significantly increased mortality, prolonged hospitalization, and elevated healthcare costs. These findings can provide further impetus to effective vancomycin stewardship.