The 2007 definition by the Society for Healthcare Epidemiology of America (SHEA) defines AMS as a "set of coordinated strategies to improve the use of antimicrobial medications with the goal to
Decreasing the overuse of antimicrobials is expected to serve the following goals:
History[edit]
Antimicrobial misuse was recognized as early as the 1940s, when Alexander Fleming remarked on penicillin's decreasing efficacy, because of its overuse.[5]
In 1966, the first systematic assessment of antibiotic use in the Winnipeg, Manitoba, Canada general hospital was published: Medical records were reviewed during two non-consecutive four-month periods (medicine, psychiatry, urology, gynecology and surgery, orthopedics, neurosurgery, ear, nose and throat, and ophthalmology). Information was coded on punched cards using 78 columns.[6]
Others in 1968 estimated that 50% of antimicrobial use was either unnecessary or inappropriate.[7] This figure is likely the lower end of the estimate, and continues to be referenced as of 2015.[8]
In the 1970s the first clinical pharmacy services were established in North American hospitals. The first formal evaluation of antibiotic use in children regarding antibiotic choice, dose and necessity of treatment was undertaken at The Children's Hospital of Winnipeg. Researchers observed errors in therapy in 30% of medical orders and 63% of surgical orders.[9] The most frequent error was unnecessary treatment found in 13% of medical and 45% of surgical orders. The authors stated "Many find it difficult to accept that there are standards against which therapy may be judged."
In the 1980s the antibiotic class of cephalosporins was introduced, further increasing bacterial resistance. During this decade infection control programs began to be established in hospitals, which systematically recorded and investigated hospital-acquired infections. Evidence-based treatment guidelines and regulation of antibiotic use surfaced. Australian researchers published the first medical guideline outcomes research.
The term AMS was coined in 1996 by two internists at Emory University School of Medicine, John McGowan and Dale Gerding, a specialist on C. difficile. They suggested "...large-scale, well-controlled trials of antimicrobial use regulation employing sophisticated epidemiologic methods, molecular biological organism typing, and precise resistance mechanism analysis [...] to determine the best methods to prevent and control this problem [antimicrobial resistance] and ensure our optimal antimicrobial use stewardship" and that "...the long-term effects of antimicrobial selection, dosage, and duration of treatment on resistance development should be a part of every antimicrobial treatment decision."[10]
In 1997, SHEA and the Infectious Diseases Society of America published guidelines to prevent antimicrobial resistance arguing that "…appropriate antimicrobial stewardship, that includes optimal selection, dose, and duration of treatment, as well as control of antibiotic use, will prevent or slow the emergence of resistance among microorganisms."[11]
Ten years later, in 2007, bacterial, antiviral and antifungal resistance had risen to such a degree that the CDC rang the alarm . The same year, IDSA and SHEA published guidelines for developing an AMS program.[12] Also in 2007, the first pediatric publication used the term AMS.[13]
A survey of pediatric infectious disease consultants in 2008 by the Emerging Infectious Disease Network revealed that only 45 (33%) respondents had an AMS program (ASP), mostly from before 2000, and another 25 (18%) planned an ASP (data unpublished).
In 2012, the SHEA, IDSA and PIDS published a joint policy statement on AMS.[14]
The CDC's NHSN has been monitoring antimicrobial use and resistance in hospitals that volunteer to provide data.[15]
On September 18, 2014, President Barack Obama issued an Executive Order 13676, "Combating Antibiotic-Resistant Bacteria.' This Executive Order charged a Task Force to develop a 5-Year action plan that included steps to reduce the emergence and spread of antibiotic-resistant bacteria and ensure continued availability of effective therapies for infections. Improved AMS is one of the charges of this Executive Order. The Presidential Advisory Council on Combating Antibiotic-Resistant Bacteria (PACCARB) was formed in response to this Executive Order.[16][17]
In 2014, the CDC recommended, that all US hospitals have an antibiotic stewardship program (ASP).[18]
On January 1, 2017 Joint Commission regulations went into effect detailing that hospitals should have an AMS team consisting of infection preventionist(s), pharmacist(s), and a practitioner to write protocols and develop projects focused on the appropriate use of antibiotics.[19] Effective January 1, 2020, the Joint Commission antimicrobial stewardship requirements were expanded to outpatient health care organizations as well.[20] In 2018, a survey of AMS programs in the US showed each 0.50 increase in pharmacist and physician full-time equivalent support predicted a roughly 1.5-fold increase in the programs effectiveness.[21] but in a 2019 survey 45% of responding physicians reported that their institution provided no support for their ASP services.[22]
Locations[edit]
AMS is needed wherever antimicrobials are prescribed in human medicine, namely in acute care hospitals, outpatient clinics, and long-term care institutions, including hospice.
Guidelines for prudent or judicious use in veterinary medicine have been developed by the Canadian Veterinary Medicine Association in 2008.[23] A particular problem is that veterinarians are both prescribers and dispensers. As of 2012, regulators and the Federation of Veterinarians of Europe had been discussing the separation of these activities.[24]
Participants[edit]
Antimicrobial stewardship focuses on prescribers, be it physician, physician assistant, nurse practitioner, on the prescription and the microorganism, if any. At a hospital, AMS can be organized in the form of an AMS committee that meets monthly. The day-to-day work is done by a core group, usually an infectious disease physician, who may or may not serve in hospital epidemiology and infection control, or/ and an infectious diseases or antimicrobial certified pharmacist, ideally but rarely aided by an information technologist.[25] In most cases, both the infectious diseases physician and the infectious diseases pharmacist co-chair the AMS committee and both serve as the directors and champions of the AMS program and committee. The entire committee may include physician representatives, who are top antimicrobial prescribers such as physicians in intensive care medicine, Hematology -Oncology, cystic fibrosis clinicians or hospitalists, a microbiologist, a quality improvement (QI) specialist, and a representative from hospital administration. Six infectious diseases organizations, SHEA, Infectious Diseases Society of America, MAD-ID, National Foundation for Infectious Diseases PIDS, and Society of Infectious Disease Pharmacists, published joint guidance for the knowledge and skills required for antimicrobial stewardship leaders.[26]
For an AMS program to be established the institution has to recognize its value. In the US it has become customary to present a business plan to the executive officers of the hospital administration.
The day-to-day work of the core AMS members is to screen patients' medical records in a prospective audit for some of the following questions, in order of importance:
If the answer is no, the team needs to effectively communicate a recommendation, which may be in person or in the medical record.
Further tasks are:
In 2010, two pediatric infectious disease physicians suggested to look at the following variables to judge the outcome of AMS interventions:[32]
When examining the relationship between an outcome and an intervention, the epidemiological method of time series analysis is preferred, because it accounts for the dependence between time points.
A review of 825 studies evaluating any AMS intervention in a community or hospital setting revealed a low overall quality of antimicrobial stewardship studies, most not reporting clinical and microbiological outcome data.[33]
A 2014 global stewardship survey identified barriers to the initiation, development and implementation of stewardship programmes internationally.[34]
In 2021, a systematic review was conducted to explore antimicrobial stewardship implementation before and during the COVID-19 pandemic in acute care settings (Elshenawy et al., 2023). It investigates AMS interventions before and during the pandemic, aiming to explore the most common antimicrobial stewardship interventions and outcome measures over the previous 20 years, including the COVID-19 pandemic. The review emphasises the importance of selecting effective strategies to combat antimicrobial resistance. Recommendations include establishing multidisciplinary stewardship teams, prioritizing core strategies initially, and tailoring interventions to local resources. Prospective audits with feedback, antimicrobial guidelines, and measures, such as Procalcitonin-guided prescribing, show promise during the pandemic or crisis. Standardizing measures such as DDD and DOT is crucial for outcome comparison. The integration of Computerized Decision Support Systems is advocated for sustained AMS implementation and preparedness for future crises.[35]
At this time the optimal metrics to benchmark antimicrobial use are still controversial:
How to best modify prescriber behavior has been the subject of controversy and research. At issue is how feedback is presented to prescribers, individually, in aggregate, with or without peer comparisons, and whether to reward or punish.
As long as the best quality metrics for an AMS program are unknown, a combination of antimicrobial consumption, antimicrobial resistance, and antimicrobial and drug resistant organism related mortality are used.[37]