Antibiotic Stewardship Programs in Long-Term Care Facilities

Antibiotic stewardship programs (ASPs) are relatively new in long-term care (LTC) facilities, but they are important to control antibiotic overuse and antibiotic resistance. A stepwise approach to ASPs is recommended. The initial steps are those that are the least costly and intrusive, including passive monitoring of antimicrobial usage and resistance, and educating LTC providers. If additional steps are required, LTC facilities may employ measures that direct the prescribing practices of providers, such as by implementing guidelines. Alternatively, the program may intervene once the antibiotic has been prescribed, such as by putting measures in place so that real-time feedback is provided for antibiotic cases. Finally, the facility may opt for an antimicrobial appropriateness review, this approach is expensive, because expert review of individual cases is required, and has the limitation of being subjective.
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The World Health Organization has reported that antibiotic resistance is one of the major threats to human health, especially because some bacteria have developed resistance to all known classes of antibiotics.¹ Diseases caused by these resistant bacteria, although more common in acute care hospitals, are also increasing in long-term care (LTC) facilities.² The frequent use of antibiotics in LTC settings has led to the selection of a resistant flora,^3,4 and the proximity of residents and contact between residents and healthcare workers facilitates the spread of these organisms.⁵ Implementation of antimicrobial stewardship programs (ASPs), which promote the appropriate use of antimicrobials, has the potential to limit antimicrobial resistance in LTC settings, while improving treatment efficacy, minimizing drug-related adverse events, and reducing treatment-related costs. In this article, we provide an overview of ASPs in healthcare facilities and discuss how components of ASPs can be applied to the LTC setting.

Antibiotic Use in LTC Settings

Antibiotics are used extensively in LTC facilities. Surveys of LTC residents found an antibiotic usage point prevalence of approximately 7% to 10%,^6-8 with antibiotics frequently given for extended periods of time.⁹ The range of antibiotic courses per 1000 resident days is 1.6 to 12.1,¹⁰ and between 50% and 70% of residents will receive at least 1course of antibiotics each year.^6,11,12

Antibiotic administration in LTC facilities, as in hospitals, has generally been suboptimal when measured by a variety of appropriateness indicators. Although antibiotic usage varies between LTC facilities,¹³ antibiotics are generally thought to be overused. Various studies suggest that 25% to 75% of systemic antimicrobials and up to 60% of topical agents are inappropriately prescribed in LTC settings.^6-8 Treatment of asymptomatic bacteriuria in catheterized residents, for example, is frequently inappropriate.¹⁴

Studies assessing antibiotic prescribing practices vary in a number of ways, particularly with regard to the standard that is used for judging appropriateness. This has led to considerable variability in the literature, with appropriateness ranging from 11% when the standard was a published consensus LTC treatment guideline,^7,15 to 50% when the standard was whether a better drug was available,¹⁶ to 78% when the standard was whether the infecting organism was sensitive to the prescribed antibiotic.¹⁰ One reason for low appropriateness scores is the frequent use of phone prescribing; a 1990 study by Katz and colleagues¹⁷ found that the majority of antibiotic prescriptions were made by telephone order. Another factor contributing to variable appropriateness results is the mix of different healthcare providers treating LTC patients. Physicians generally prescribe fewer antibiotics than nonphysician clinicians, but the former are not always available in LTC facilities.¹⁸

Evaluating antibiotic appropriateness is difficult and often subjective. Methods for determining appropriateness have included using outside experts to develop criteria, convening panels of experts to review individual cases, and applying surveillance criteria to assess whether the resident in question has met the criteria for an infectious disease. In 1986, Zimmer and associates⁸ developed appropriateness criteria in consultation with a group of medical directors and found that only 62% of cases had sufficient evidence for initiation of antimicrobials. In 1987, Jones and colleagues¹⁶ judged appropriateness by using a panel of 2 board-certified infectious disease experts and 1 pharmacist, and found that only 49% of treatment courses were appropriate. In 1992, Beers and associates¹⁹ convened a panel of 13 experts to develop criteria to determine antibiotic appropriateness in LTC facilities, and found that 40% of residents received at least 1 inappropriate antimicrobial and that more inappropriate medications were ordered in larger LTC facilities than in smaller ones. Finally, in 2001, Loeb and colleagues⁹ evaluated antibiotic prescriptions using standardized surveillance definitions of common infections, and found that only 49% of all prescriptions for infection met diagnostic criteria.

Antibiotic Resistance in LTC Settings

Numerous outbreaks of infection and colonization of multidrug-resistant organisms (MDROs) have been reported in LTC facilities, and the incidence of MDROs in LTC settings is increasing significantly.² The most common MDROs described in LTC facilities have been methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE), although gram-negative organisms, such as Klebsiella and Acinetobacter, are being seen with increasing frequency.^4,20,21 Transmission of these MDROs to previously noncolonized residents has been observed.²²

ASPs in LTC Settings

ASPs have been developed because inappropriate antimicrobial use has been associated with selection of resistant organisms, and the finding in multiple studies that antibiotic use is often inappropriate.²³ The primary goal of antibiotic stewardship is to optimize clinical outcomes while minimizing unintended consequences of antimicrobial use, including toxicity, the selection of pathogenic organisms (such as Clostridium difficile), and the emergence of resistance. In 2007, the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA) jointly published a guideline on ASPs outlining scientific evidence for various interventions that could be included in an acute care hospital ASP.²³ While formal programs that combine a number of measures or practices aimed at improving antibiotic use are now relatively common in acute care hospitals, this is not the case in LTC facilities, despite several guidelines^3,24,25 being issued that are applicable to this setting.

In 2008, the Association for Professionals in Infection Control and Epidemiology (APIC) and SHEA issued a guideline for infection prevention and control in LTC facilities, which recommends using ASPs.²⁴ This recommendation was classified as a category IB, signifying a strong theoretical rationale for the guideline based on support from experimental, clinical, or epidemiologic studies. The guideline indicates that the ASP should monitor local antimicrobial susceptibilities, with any observed changes reported to appropriate parties. In 2006, the Centers for Disease Control and Prevention issued a guideline for managing MDROs in healthcare settings, which expected all facilities, including LTC facilities, to have a multidisciplinary process for reviewing local antimicrobial susceptibility patterns (antibiograms), antimicrobial use, and antimicrobial agents included in the institutional formulary.³ The LTC facility should also have a system prompting clinicians to use the appropriate antibiotic, and, at a minimum, review and distribute antimicrobial usage trends. If MDRO rates are not decreasing, or a new MDRO appears, the facility needs to intensify control efforts by reviewing the role of antibiotics in the MDRO and targeting high-risk antibiotics.

The Centers for Medicare & Medicaid Services interpretive guidance for surveyors notes that antibiotic review should be part of the infection control program; this should include reviewing data to monitor the appropriateness of antibiotic usage in LTC facilities.²⁵ Susceptibility report review is suggested as part of this process.

ASP Strategies

A variety of approaches to stewardship is possible in LTC settings, but an administrative infrastructure is required. Many potential barriers may need to be overcome before successful implementation, including lack of dedicated personnel, absence of electronic records, lack of published guidelines specific to the LTC facility, lack of knowledge of pertinent treatment guidelines, lack of appropriate staff training, lack of access to infectious disease experts, and lack of onsite pharmacy support.⁵ ASP measures that can be used in LTC settings are shown in the Figure.

Passive Monitoring
Passive monitoring is the most basic intervention. As previously noted, established guidelines^3,23-25 generally recommend monitoring antibiotic resistance (laboratory results and facility antibiograms) and antibiotic usage patterns (with the help of the consultant pharmacist), which depend on institutional resistance patterns, resident acuity, available formulary, and physician prescribing preferences. Information about antibiotic usage may be presented in a number of formats, including days of therapy, defined daily doses per 1000 patient days,²³ and the number of residents treated with antibiotics per month.¹¹ Although most LTC facilities do not have an onsite laboratory, the reference laboratory should be asked to provide cumulative data on antimicrobial susceptibility in the form of a facility-specific antibiogram.²⁶ Other information to be collected could include type of antibiotic ordered, route of administration, antibiotic costs, and whether the order was made by phone, whether a culture was obtained before ordering, and whether the antibiotic was changed during the course of treatment.^13,16 LTC facilities should collect all available and relevant information regarding antibiotic administration at their institution.

A survey of Minnesota LTC facilities found that approximately half of the respondents followed antibiotic susceptibility reports, and most tracked MDROs, especially MRSA and VRE.⁵ The collected data were regularly sent to the director of nursing, but were seldom sent to clinical staff. Ideally, antibiotic use information should be distributed to clinicians and all personnel who are responsible for infection control and quality improvement.

Education
Education is an important part of any multifaceted program, and has been effective in LTC settings when combined with other measures.^27,28 Although passive education (eg, conference presentations, teaching sessions, distribution of educational materials, email alerts, or one-on-one academic detailing) is nonthreatening, when used alone, it often fails to have a sustained effect.²³ One randomized controlled trial by Loeb and colleagues²⁹ that compared usual care with a multifaceted intervention using a diagnostic and treatment algorithm for urinary tract infections (UTIs) along with intensive education (ie, small group interactive sessions for nurses, videotapes, written material, outreach visits, and one-on-one interviews with physicians) found that the multifaceted approach reduced the number of antimicrobial prescriptions for suspected UTIs in LTC residents compared with standard care.²⁹ Other authors have noted similar improvement in antimicrobial use with educational interventions^28,30,31; however, intensive educational methods may be beyond the means of most LTC facilities and are difficult to sustain, as was demonstrated in the study by Loeb and colleagues,²⁹ where the effect of the interventions slowly decreased, and by 12 months antibiotic use was no different between the facilities that used the intervention and those that did not.

Since the durability of educational effects in antibiotic education is limited,¹⁴ educational programs ideally need to be varied in approach, repeated regularly, combined with other measures, and made locally relevant. An example of this varied approach to education would be combining didactic sessions with feedback on individual physician prescribing patterns, or discussing how national guidelines apply to individual cases at LTC facilities. There are many evidence-based guidelines, but not all are applicable to LTC settings, and compliance with guidelines is poor³²; thus, discussion of the guidelines may be helpful, especially to nonphysician clinicians who may not be as familiar with the available literature. To facilitate dialogue, the guidelines should ideally be broken down into small segments, applied to individual facilities, and discussed by providers in relation to actual resident cases. One LTC facility developed evidence-based algorithms and applied them to local cases in small teaching sessions for providers using an audience response system.²⁸ This strategy increased compliance with the algorithms and led to a subsequent decrease in antimicrobial use. “

Front-End” Approaches
The front-end approaches, whether passive or active, attempt to improve the quality of antibiotic usage by influencing the initial choice of antimicrobial. The methods used may be less restrictive (eg, making national antimicrobial treatment guidelines available to the prescriber, having an institutional formulary, developing local treatment algorithms for certain infections) or more restrictive (eg, using an antimicrobial order form that requires prescriber justification, requiring approval of an antimicrobial order). Requiring preauthorization has been used successfully in hospitals,^23,33 but requires available infectious disease staff. Lack of expertise in antimicrobial management would pose a problem for most LTC facilities, even if the medical staff found preauthorization an acceptable option.

“Back-End” Approach
The back-end approach is more time-consuming and labor intensive because it involves concurrent review of antimicrobial therapy. In one geriatric hospital, an infectious disease expert developed an antibiotic guide and gave feedback to prescribers following weekly rounds wherein actual prescribing was compared with recommendations outlined in the antibiotic guide.²⁷ In some hospitals, daily clinician feedback is provided via phone calls or chart notes. Other hospitals have focused on streamlining or discontinuing antibiotics,³⁴ or targeting use of high-risk antibiotics.³⁵ While daily interventions have been associated with decreased antibiotic use,³⁶ and less frequent interventions have also been helpful,³⁷ there is virtually no experience with the usefulness and practicality of this approach in LTC facilities.

Assessment of Antimicrobial Appropriateness

Assessment of the appropriateness of antimicrobial use is labor intensive, requiring individual case review or creation of guidelines by experts with application to current cases.^8,19,29,31 Such review is generally conducted by outside experts, usually infectious disease specialists, who need to evaluate individual cases on site; however, applying this method to LTC facilities has several limitations. Ongoing appropriateness review is expensive, and experts may differ in their subjective interpretation of treatment appropriateness. An outside expert may not be familiar with all of the medical, logistic, and ethical factors that are involved in the care of LTC patients. Finally, the determination of appropriateness in the LTC setting can vary widely depending on the criteria applied.¹⁰

Antimicrobial appropriateness assessments, if performed in LTC facilities, should focus on objective problems, such as prescribing antibiotics for asymptomatic bacteriuria or viral upper respiratory tract infections.⁷ Other areas could include adherence to facility guidelines, adjustment of therapy according to culture results, use of appropriate dose, and proper duration of therapy. The consultant pharmacist could screen cases for further review.³⁸ LTC facilities may also choose to set benchmarks for antibiotic use and costs.³⁹

Getting Started

Implementing ASPs in LTC facilities may be challenging, as there are often limited resources; however, as outlined in the Figure, a number of measures can be implemented with minimal expense and effort. Existing guidelines for implementation of ASPs are hospital-oriented, but several steps seem applicable to LTC facilities (Table).

To be successful, an ASP requires the support of key individuals in LTC facilities. At a minimum, this includes representatives from administration, clinical staff (including nurses and physicians), infection control, pharmacy, and the medical director. Control of resistant pathogens requires both rigorous infection control procedures and appropriate antimicrobial use, so the involvement of infection control personnel is critical.¹⁰

Basic elements of an LTC ASP would include reporting and monitoring of MDROs (eg, MRSA, VRE), tracking antibiotic usage, and conducting various education initiatives. The facility should ensure that both the clinician and the facility are notified promptly by the reference laboratory when a new MDRO is identified. Cumulative antimicrobial susceptibility reports should be sent to the facility periodically (at least annually) and then made easily available to all clinical staff and infection control personnel. With the assistance of the consultant pharmacist, facilities can monitor cumulative antibiotic usage, use of specific antibiotics, and antibiotic costs and trends.

Education should advance beyond the standard lecture format; ideally, it should be interactive, based on actual LTC cases, and keyed to published guidelines when applicable. IDSA guidelines^15,23 should be adapted to the particular LTC setting. An appropriate initial target for the ASP would be use of antimicrobials to treat UTIs. Many patients with asymptomatic bacteriuria are treated inappropriately with antibiotics in LTC facilities.^14,29,30 Current IDSA guidelines addressing this issue in both catheterized and noncatheterized patients recommend against treating asymptomatic bacteriuria.^40,41 Education programs could be developed that describe UTI symptoms, appropriate situations for obtaining a urine culture, and indications for treatment. Similar successful interventions to decrease general LTC antimicrobial use have been published in the literature.^28,30,31

Ideally, LTC facilities should begin with the most easily implemented measures, as outlined at the top of the Figure. More advanced measures may be added incrementally based on available resources and institutional needs, building upon previous successes. Outside expertise may be needed if basic measures are inadequate to control antibiotic usage or MDRO prevalence in the facility. Some resistance to change in institutions is typical, but antibiotic stewardship is an important aspect of resident safety in the face of spiraling antibiotic resistance issues.

Conclusion

Although the prevalence of MDROs can vary considerably between regions, facilities, and healthcare settings, their incidence is increasing, including in LTC. To slow the development and spread of these pathogens, LTC facilities should consider implementing ASPs, which are already common in acute care hospitals. While several studies have found ASPs to be beneficial in LTC, there are considerable challenges to implementing and maintaining these programs; however, a gradual approach, as outlined in this article, can facilitate the process and may help achieve durable results.

The authors report no relevant financial relationships.

Dr. Smith is professor, Division of Infectious Diseases, Department of Internal Medicine, University of Nebraska Medical Center; Ms. Watkins is librarian/grants coordinator, and Ms. Miller is student extern Center for Preparedness Education, University of Nebraska College of Public Health;, Center for Preparedness Education, University of Nebraska College of Public Health, Omaha, and Dr. VanSchooneveld is medical director, Antibiotic Stewardship Program, the Nebraska Medical Center, Omaha, and assistant professor, Division of Infectious Diseases, Department of Internal Medicine, University of Nebraska Medical Center, Omaha. References 1. Gaynes RP. Preserving the effectiveness of antibiotics. JAMA. 2010;303(22):2293-2294.

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