National Meeting 2007

3110 — A Longitudinal Study of Antibiotic Use Control Guidelines in VA and US Hospitals Predicting Change in Antimicrobial Resistance

Zillich AJ (Purdue University College of Pharmacy and VA Center of Excellence in Implementing Evidence-based Practices, Roudebush VAMC) , Sutherland JM (VA Center of Excellence in Implementing Evidence-based Practices, Roudebush VAMC and Indiana University), Flanagan ME (VA Center of Excellence in Implementing Evidence-based Practices, Roudebush VAMC), Doebbeling BN (VA Center of Excellence in Implementing Evidence-based Practices, Roudebush VAMC and Indiana University)

Inappropriate use of antibiotics and control of antimicrobial resistance (AMR) are major patient safety, hospital management, and public health issues. Practices to control antibiotic use have been recommended, however whether these practices impact AMR rates in hospitals over time is unknown. We sought to identify relationships between antimicrobial use control strategies and changes in AMR in a longitudinal sample of VA and comparable U.S. hospitals.

A nationally representative sample (n=670) of all acute care VAMCs and comparable U.S. hospitals, were stratified by bed size, teaching status, and geographic region. We surveyed hospital lab directors and infection control practitioners in 2001 and again in 2003. The dependent measures reflected the change in prevalence for each of four clinically-important types of AMR: 1) methicillin-resistant Staphylococcus aureus, 2) vancomycin-resistant enterococci, 3) extended-spectrum beta-lactamase resistance, and 4) quinolone-resistant E. coli. Independent variables included recommended national guidelines to control antimicrobial prescribing, including change in: 1) implementing and disseminating guidelines for antimicrobial use, 2) ensuring practices for appropriate antibiotic use, 3) antimicrobial-related information technology, 4) decision support tools, and 5) communicating antimicrobial usage to prescribers. Control variables included the stratification variables and baseline covariates (baseline AMR levels, number of long-term care beds, intensive care unit (ICU), a burn unit, or transplant services). Generalized estimating equation modeled change in the four types of AMR rates simultaneously.

The cohort included 250 hospitals (of 448 hospitals at baseline) with complete data at both time points. Baseline variables of teaching status, urban location, and New England geographic region were associated with increased AMR. VA hospitals had a significant decrease in AMR. Importantly, an improvement in communication of trends in antimicrobial usage to prescribers was associated with a decrease in overall AMR prevalence (p<0.01).

VA hospitals implemented measures to decrease AMR. Strategies to report antimicrobial usage to providers appear to be effective in reducing AMR. Effective strategies to control antimicrobial use should be more widely implemented and tested.

These data suggest that strategies to feedback prescribing patterns to providers and specific strategies implemented in VA help control all types of AMR in hospitals.