Antimicrobial Stewardship Programs as a Means to Optuimize Anitmicrobial Use

Robert C. Owens, Jr., Pharm.D.; Gilles L. Fraser, Pharm.D., FCCM; Patricia Stogsdill, MD


Pharmacotherapy. 2004;24(7) 

In This Article

Rationale for Optimizing Antimicrobial Use

Central to the argument for promoting good antimicrobial stewardship is the growing concern about antimicrobial resistance and patient safety. Peripheral to the central arguments, albeit important, is cost containment. Optimizing antimicrobial use reduces pharmacy expenditures safely in patients and is important to health care system viability in modern times. Optimizing antimicrobial use by minimizing exposure to the drugs, adjusting dosage, reducing redundant therapy, and targeting therapy to the likely pathogens is viewed as a strategy to enhance patient safety.[7]

In terms of impact on antimicrobial resistance, however, the role of optimizing antimicrobial use can be more nebulous because the factors promoting resistance are complex and numerous, extending beyond the use of antimicrobial agents in humans. As such, it is not surprising that these factors do not allow for quick fixes.[8] Studies have established a strong relationship between antimicrobial use and resistance. One study showed a clear relationship between antimicrobial use and the selection of resistance in humans, documenting biologic plausibility.[9]

Data derived from various types of studies have provided sufficient evidence to establish causal relationships.[10,11,12,13,14,15,16] These were in vitro studies in which drug exposure selected for resistance, ecologic studies that correlated drug exposure with resistance, controlled studies in which patients who had been treated with antimicrobial drugs were more likely to be colonized or infected with resistant bacteria, and prospective studies in which drug treatment was associated with the development of resistant flora.

As stated by the Interagency Task Force for Antimicrobial Resistance, "appropriate antimicrobial drug use is defined as use that maximizes therapeutic impact while minimizing toxicity and the development of resistance. In practice, this involves prescribing antimicrobial therapy when and only when it is beneficial to the patient, targeting therapy to the desired pathogens, and using the appropriate drug, dose, and duration. Appropriate antimicrobial drug use should not be interpreted simply as reduced use, because these drugs offer valuable benefits when used appropriately. It is overuse and misuse that must be decreased to reduce the selective pressure favoring the spread of resistance."[6] Hence, extending the useful life of antimicrobial agents requires that they be used appropriately.[10]

Early on, pioneers in the field realized that antimicrobials had the potential to be misused and that strategies were needed to guide the agents' optimal use; this resulted in the first formalized efforts to ensure the appropriateness of antimicrobial therapy.[17] Antimicrobial stewardship programs have evolved as a means for clinicians to optimize antimicrobial use in hospitals in accordance with consensus recommendations. A decade ago, the literature described a multitude of strategies ranging from many individual interventions (e.g., formulary manipulations, dosing recommendations, and academic detailing) to less common but more broad and programmatic approaches (e.g., prior-approval programs, concurrent review and feedback).

All of these strategies seemed effective in controlling antimicrobial expenditures, but their effect on clinical and microbiologic outcomes was not as ostensible. To this end, an increasing body of literature has contributed to establishing and clarifying the role and benefit of antimicrobial stewardship programs relative to their impact on appropriate antimicrobial use, clinical outcomes, antimicrobial resistance, and, of course, costs.[18,19,20]