Financial Impact of an Antimicrobial Stewardship Program Over Seven Years in a Large Academic Medical Center

Background: Jackson Memorial Hospital (JMH) is a 1500 bed, tertiary academic medical center that serves a diverse patient population. In 2002, JMH established an Antimicrobial Stewardship Program (ASP) focused on restricting antifungal agents, with a goal of minimizing antimicrobial resistance and expenditures. The ASP has expanded interventions to include additional restrictions, formulary changes, and prospective audit with feedback to promote appropriate utilization of antimicrobials. For fiscal year 2002, the total antimicrobial expenditure excluding antiretrovirals was $8.6 million. Given the mean annual antimicrobial expenditure inflation rate for US hospitals of 7%, the projected antimicrobial expenditure for 2009 at JMH is $13.8 million.

Objective: To compare antimicrobial expenditures at JMH from 2002 to 2009 and to evaluate the financial impact of selected ASP interventions over the year 2008 to 2009.

Methods: Overall expenditure reports for antimicrobials (excluding antiretrovirals) were compared for 2002 and 2009. Raw purchasing reports were used to determine expenditures. Adjusted and inflation-adjusted expenditures for 2009 were compared. Expenditures for selected antimicrobials targeted by the ASP between 2008 and 2009 were also evaluated.

Results: Expenditures for antimicrobials decreased from $8.6 million in 2002 to $8.3 million in 2009, a $5.2 million savings compared with the inflation-adjusted expected expenditure for 2009. Between 2008 and 2009, there was a decrease in expenditures from $8.5 to $8.3 million. Decreases in expenditures were seen for 3 antimicrobials for which major interventions were conducted: conversion of branded Tobi^® to intravenous tobramycin for inhalation ($107,000), prospective audit with feedback for piperacillin/tazobactam ($252,000), and formulary substitution in the carbapenem class ($68,000). Decreases were also seen for fluoroquinolones ($100,000), quinupristin/dalfopristin ($95,000), and vancomycin ($50,000). Expenditures were stable forcefepime, daptomycin, linezolid, and tigecycline. Expenditures increased for lipid amphotericin, voriconazole, and valganciclovir.

Conclusions: Antimicrobial expenditures at JMH have remained ~$8.5 million annually for the years 2002 and 2009, with an estimated cost savings of $5.2 million based on the inflation-adjusted estimated expenditure for2009. Multiple interventions appear to have been successful in reducing expenditures for the year 2008 to 2009. It is possible that other factors not measured in this study impacted antimicrobial expenditures, such as changes in patient census, case mix, or expiration of patent protection, but it is doubtful that such factors could have contributed significantly to the dramatic costs savings we have demonstrated. Our ASP appears to have a significant beneficial financial impact on JMH.