According to the Centers for Disease Control and Prevention (CDC), more than 2 million people in the United States develop an antibiotic-resistant infection each year.1 Antibiotic overuse and misuse are primary drivers behind the growing problem of antibiotic-resistant diseases worldwide. Antibiotic stewardship programs (ASPs) are interventions designed to optimize the use of antibiotics in medical facilities and at home.
Tamar Barlam, MD, is with the section of infectious diseases at Boston University School of Medicine in Massachusetts. She was lead author of comprehensive guidelines for implementing an ASP that were completed by the Infectious Diseases Society of American (IDSA) and the Society for Healthcare Epidemiology of America (SHEA) in 2016.2 In an interview with Infectious Disease Advisor, Dr Barlam noted that ASPs have a beneficial impact wherever antibiotics are used. “Antibiotic stewardship programs have consistently demonstrated improved patient outcomes. They improve clinical treatments and cures and reduce adverse effects related to antibiotic use. They also reduce Clostridium difficile infections (CDIs) and the emergence and prevalence of antibiotic-resistant[ce] bacteria,” she said.
A group of German researchers recently conducted a meta-analysis of 32 studies on how ASPs affect the risk of infection with antibiotic-resistant bacteria or C difficile in hospital patients.3 They observed significant reductions in infection or colonization with various types of antibiotic-resistant bacteria, including a 51% reduction in multidrug-resistant Gram-negative bacteria (incidence ratio [IR], 0.49; 95% CI, 0.35-0.68; P <.0001); a 48% reduction in extended-spectrum β-lactamase-producing Gram-negative bacteria (IR, 0.52; 95% CI, 0.27-0.98; P =.042); and a 37% decrease in methicillin-resistant Staphylococcus aureus (MRSA) (IR, 0.63; 95% CI, 0.45-0.99; P =.0065). Data also showed a 32% reduction in CDIs (IR, 0.68; 95% CI, 0.53-0.88; P =.0029).3 The guideline authors found no relationship between ASPs and the incidence of vancomycin-resistant enterococci, quinolone-resistant Gram-negative bacteria, or aminoglycoside-resistant Gram-negative bacteria.3
There are not enough data from well-conducted studies to determine the optimal ASP model.2 However, Dr Barlam said the framework for every ASP begins with “a process to review antibiotic choices and indications either at the start of treatment…or in the first days of treatment, as the patient’s clinical situation becomes clearer and more data become available.” As an example, she said the ASP might include “a process that requires preauthorization by the stewardship program for the antibiotic to be given.” According to IDSA/SHEA guidelines, preauthorization can promote chart review and reduce the use of unnecessary or inappropriate antibiotics. The tighter control over antibiotic use may contribute to lower costs for the institution and allow faster responses to antibiotic shortages. Another ASP model is prospective audit and feedback (PAF), which a meta-analysis by Baur and colleagues found was relatively effective.3 With PAF, the intervention occurs after the provider has prescribed an antibiotic and frequently leads to changing or discontinuing an inappropriately prescribed agent.2 Regardless of the ASP model used, Dr Barlam said good results depend on consistent implementation.
In addition to implementing facility-wide interventions such as preauthorization or PAF, IDSA/SHEA advise facilities to adopt approaches that target specific infections.2 “The benefit of targeting specific infectious diseases by ASPs is not only a more focused use of resources, it also sends a more targeted message to providers, which hopefully can result in more sustained improvements in antibiotic use,” Dr Barlam said. She added that some of the most successful ASP interventions have targeted pneumonia, bloodstream infections (especially with MRSA), skin and soft-tissue infections, and urinary tract infections.
The type of facility or patient population may dictate which interventions are needed most. Dr Barlam explained that while hospice patients typically have limited antibiotic use and may require less aggressive ASPs, an ASP “can be of tremendous importance in any hospitalized patient and for patients in nursing homes.” Multidrug-resistant organisms are commonly found in many hospital wards and skilled nursing facilities. When Baur and associates analyzed reductions in the incidence of antibiotic-resistant infection by setting, they found hematology-oncology departments (59% reduction; IR, 0.41; 95% CI, 0.20-0.85; P =0.0166), intensive care units (23% reduction; IR, 0.77; 95% CI, 0.66-0.89; P =.003), and medical departments (22% reduction; IR, 0.78; 95% CI, 0.66-0.91; P =.0024) derived the greatest benefit from ASPs.3
Although the IDSA/SHEA guidelines believe well-trained infectious disease physicians are the best providers to lead ASPs, Dr Barlam noted that may not always be possible. “Nursing homes often do not have on-site physicians or physicians or pharmacists trained in infectious disease,” she said. Optimizing outcomes with an ASP requires a team approach that involves point-of-care providers. Dr Barlam said, “Nurses take on an even greater role as important team members for an ASP based in a nursing home.”
Once a facility has implemented an ASP, measuring its effectiveness is critical to success. “Antibiotic use must be measured on a regular basis to watch for any trends in use,” Dr Barlam said. Doing so allows the facility to determine whether the ASP is working as intended and to identify areas where specific interventions are needed. She stressed the importance of defining the goals of a specific intervention and monitoring progress toward those goals. “For example, if an ASP wants to reduce MRSA coverage for uncomplicated cellulitis, baseline use of anti-MRSA agents must be measured; after the intervention is put in place, changes in use of those agents must be monitored,” she said.
Dr Barlam emphasized how much antibiotics have revolutionized healthcare, but the spread of antibiotic-resistant bacteria threatens that progress. “Although there are some new antibiotics being developed, antibiotic resistance is outstripping that development significantly,” she said. “Our best strategy is to optimize our use of existing antibiotics, and ASPs help preserve these priceless treatments for as long as possible,” she concluded. More good-quality studies are needed to identify which ASPs perform best in specific settings.
- Centers for Disease Control and Prevention (CDC). Antibiotic/antimicrobial resistance. Updated August 18, 2017. Accessed September 20, 2017.
- Barlam TF, Cosgrove SE, Abblo LM, et al. Implementing an antibiotic stewardship program: guidelines by the Infectious Diseases Society of American and the Society for Healthcare Epidemiology of America. Clin Infect Dis. 2016;62(10):e51-e77.
- Baur D, Gladstone BP, Burkert F, et al. Effect of antibiotic stewardship on the incidence of infections and colonization with antibiotic-resistant bacteria and Clostridium difficile infection: a systematic review and meta-analysis. Lancet Infect Dis. 2017;17:990-1001.