Antimicrobial stewardship teams help save lives

Antimicrobial stewardship teams that include infectious disease (ID) pharmacists and physicians in hospital settings can encourage more judicious use of antibiotics, resulting in lower mortality and cost savings, according to a report published online for the American Journal of Health-System Pharmacy.

Kalvin Yu, MD, of Kaiser Permanente West Los Angeles Medical Center, Los Angeles, Calif., and his colleagues evaluated the antimicrobial stewardship programs (ASPs) at two hospitals over a 12-month period. They studied the cost and quality outcomes of a 250-bed community hospital with average antimicrobial use and a tertiary care teaching hospital with almost 400 beds with a low antimicrobial rate and then compared the results to three other hospitals with average or slightly above-average antimicrobial usage rates. Of these three hospitals, two had no ASP and the other had an ASP without an ID pharmacist.

The use of 15 targeted antimicrobial agents and their costs were compared among the five hospitals before and after ASP implementation. In addition, the researchers reviewed changes in hospital standardized mortality ratio (HSMR) values for sepsis, Clostridium difficile infections, and respiratory infections among Medicare beneficiaries.

“In the year after ASP implementation, aggregate direct antimicrobial acquisition costs at the two study sites decreased 17.3% from prior-year levels and increased by 9.1% at the three comparator sites,” Yu and his colleagues noted. “Significant decreases in the consumption of targeted antimicrobial classes…were observed at the ASP sites.”

Nearly 2,500 interventions were recorded in the electronic medical records at the two study sites with a 98% acceptance rate by the attending physician. Almost 75% of the interventions involved discontinuing or deescalating broad-spectrum antimicrobials, and only 6.3% were to escalate or prolong antimicrobial treatments.

“In aggregate, study site use of antipseudomonal agents decreased by 18.3% relative to baseline values; use of agents used to treat methicillin-resistant Staphylococcus aureus (MRSA) decreased by 9.9%, use of fluoroquinolones decreased by 16%, and use of antifungal agents decreased by 7%,” the authors noted. “In contrast, aggregate use of three of those four antimicrobial classes significantly increased from baseline at the comparator sites: antipseudomonal agents by 9.9%, anti-MRSA agents by 15%, and antifungal agents by 16.5%.”

In addition, cost for antimicrobials as measured by 1000 patient-days at the study sites declined by 17.3% during the 12-month study period compared to the preceding year. At the comparator sites, aggregate cumulative antimicrobial costs increased by 9.1% during the 12-month study.

The HSMR values for sepsis declined from 74.1% to 70.2% at the first study site and from 97.2% to 66.6% at the second study site. This trend was also seen in patients with respiratory infections where the HSMR decreased from 65.4% to 49.6% at the first study site and from 58.6% to 50.2% at the second site.

“Mortality from sepsis decreased for all hospitalized patients after ASP implementation (from 14.6% to 10.6% at site 1 and from 15.5% to 13.6% at site 2),” Yu and his co-authors wrote.

The authors did note that healthcare-associated C. difficile infection rates were similar during the study period and the preceding year. At the first study site there was a mean of 8.4 cases per 10,000 patient days before ASP implementation and a mean of 8.3 cases per 10,000 patient days after ASP implementation. The same trend was recorded at the second study site.