Evaluation of Department of Defense hospital antimicrobial stewardship programs (ASPs) using a novel Core Elements scoring approach and modeling Core Elements scores with metrics related to ASP outcomes.

Objective: Evaluate Department of Defense (DoD) antimicrobial stewardship programs (ASPs) by assessing the relationship between key clinical outcome metrics (antibiotic use, incidence of resistant pathogens, and incidence of infections) and CDC Core Element (CE) adherence.

Design: Retrospective, cross-sectional study of DoD hospitals in 2018 and 2021.

Methods: National Healthcare Safety Network Standardized Antimicrobial Administration Ratios (SAARs) were used to measure antibiotic use and microbiology results to evaluate four types of pathogen incidence. A novel CE scoring approach used scores to quantitatively assess relationships with CE adherence and outcome metrics using correlation and regression models. Assessments were repeated with 2021 data for Priority CE adherence and to conduct adjusted regressions for CEs and Priority CEs controlling for categorical bed size.

Results: Compared to 2022 national data, DoD hospitals in 2021 had a similar proportion of facilities with a SAAR statistically significantly > 1.0. Leadership, Action, and Tracking CEs followed a more normal score distribution, while Reporting and Education were somewhat left-skewed. Unadjusted models often showed a positive relationship with higher CE scores associated with worse outcomes for the SAAR and pathogen incidence. Adjusted models indicated that procedural CEs, particularly Priority Reporting, were associated with better ASP-related outcomes.

Conclusions: CEs should be more quantitatively assessed. Results provide initial evidence to prioritize procedural CE implementation within the DoD; however, additional investigation for structural CEs is needed. Patient outcome data should be collected as an important indicator of ASP performance.