VA study leads to call for more rigorous antibiotic stewardship

May 15, 2011

Antibiotic use is rising at Veterans Affairs medical facilities across the country, according to study findings released recently at the annual meeting of the Society for Healthcare Epidemiology of America in Dallas.

Key Points

Antibiotic use is rising at Veterans Affairs (VA) medical facilities across the country, according to study findings released recently during an oral presentation at the annual meeting of the Society for Healthcare Epidemiology of America (SHEA) in Dallas. Bar-code data on medication administration show that use of powerful antibiotics rose steadily during the study period of January 2005, to the end of 2009.

Researchers can't account for the increasing intensity of antibiotic treatment and suggested that more effective antibiotic stewardship programs are needed.

The sharpest rise in use was in broad-spectrum antibiotics," said lead author Makoto Jones, MD, University of Utah IDEAS Center, Salt Lake City. "More than half of patients received at least 1 dose of antibiotics during a VA hospital stay during those 5 years, and fluoroquinolones were the largest single class used, at about 20%. Our findings agree with regional and local studies relative to antibiotic use around the country."

The VA's nationwide system of electronic medication administration records made the retrospective study possible, Jones said. Researchers analyzed data on antibiotic use at 110 of 124 VA acute-care sites in 4 VA regions across the country. The other 14 sites had an average of fewer than 100 occupied patient days on acute-care wards per month over the study period or did not have bar-code data on medication administration for the entire period covered by the study.

Antibiotic use showed a gradual increase from 649 days of therapy per 1,000 patient days in early 2005 to 775 days of therapy per 1,000 patient days 5 years later. The largest increases were seen in use of carbapenems (up 102%), intravenous vancomycin (up 79%), and penicillin with beta-lactamase inhibitors (up 41%).

"The use of these broad-spectrum antibiotics affects not just patients, but everyone who works in the hospital," Jones said. "Clinicians want to hit infections hard and hit fast, which is the general recommendation for antibiotics, but we believe that antibiotic stewardship can help guide more appropriate use."

A researcher's dream

This may be the first large-scale study of antibiotic use across the country, Jones said. While the scope of the findings is unique, the national trends seen in VA hospitals mirror the findings of local and regional studies.

The study found a wide variation in antibiotic selection between facilities, he added. Fluoroquinolone use increased anywhere from 6.6% to 42.9%, depending on the facility, but mean antibiotic use was comparable across patient complexity levels and in all 4 VA regions, regardless of whether comparisons were based on the number of patient days or the number of admissions.

"The VA is a researcher's dream," Jones said. "We are palpably excited about individual patient-level studies and national studies. A database this broad and this detailed is not available anywhere else."

Organisms push back

Increasing antibiotic use is most likely associated with the perceived need to stop potentially resistant infections as soon as possible, he said. The problem is that increasing the use of broad-spectrum agents only reinforces the likelihood that drug-resistant strains will develop. Broad studies of drug-resistant organisms and antibiotic use are already in the works, Jones said.

"The use of the right antibiotic gives better outcomes than hitting everything with a broad-spectrum agent," he said, adding, "There is some basic science to be done on how to best implement antibiotic stewardship programs."

Patterns of use must change

Existing antibiotic stewardship guidelines from SHEA and other organizations acknowledge that changing accustomed patterns of drug use is not a simple task, Jones said. Potential decision points include the typical length of treatment, when to start treatment, and deescalation of treatment, as well as selection of the appropriate agent or agents to be used.

"Many facilities have limited capabilities for audit and feedback of drug use," he said. "Informatics can make a big difference. Electronic medical records will help track drug use and drug-order patterns, which will help identify key pressure points. What information is needed and at what level it is needed are things that we need to work out. We will be working to add to the literature."