OBJECTIVE: Bacterial resistance is known to diminish the effectiveness of antibiotics for treatment of urinary tract infections. Review of recent healthcare and antibiotic exposures, as well as prior culture results is recommended to aid in selection of empirical treatment. However, the optimal approach for assessing these data is unclear. We utilized data from the Veterans Health Administration to evaluate relationships between culture and treatment history and the subsequent probability of antibiotic-resistant bacteria identified in urine cultures to further guide clinicians in understanding these risk factors. METHODS: Using the XGBoost algorithm, a retrospective cohort of outpatients with urine culture results and antibiotic prescriptions from 2017 to 2022 was used to develop models for predicting antibiotic resistance for three classes of antibiotics: cephalosporins, fluoroquinolones, and trimethoprim/sulfamethoxazole (TMP/SMX) obtained from urine cultures. Model performance was assessed using Area Under the Receiver Operating Characteristic curve (AUC) and Precision-Recall AUC (PRAUC). RESULTS: There were 392,647 prior urine cultures identified in 214,656 patients. A history of bacterial resistance to the specific treatment was the most important predictor of subsequent resistance for positive cultures, followed by a history of specific antibiotic exposure. The models performed better than previously established risk factors alone, especially for fluoroquinolone resistance, with an AUC of .84 and PRAUC of .70. Notably, the models performance improved markedly (AUC = .90, PRAUC = .87) when applied to cultures from patients with a known history of resistance to any of the antibiotic classes. CONCLUSION: These predictive models demonstrate potential in guiding antibiotic prescription and improving infection management.

Objectives:Inappropriate antibiotic use poses a serious threat to patient safety. Antimicrobial stewardship programmes (ASPs) may optimize antimicrobial use and improve patient outcomes, but their implementation remains an organizational challenge. Using the Promoting Action on Research Implementation in Health Services (PARiHS) framework, this study aimed to identify organizational factors that may facilitate ASP design, development and implementation. Methods:Among 130 Veterans Affairs facilities that offered acute care, we classified organizational variables supporting antimicrobial stewardship activities into three PARiHS domains: evidence to encompass sources of knowledge; contexts to translate evidence into practice; and facilitation to enhance the implementation process. We conducted a series of exploratory factor analyses to identify conceptually linked factor scales. Cronbach's alphas were calculated. Variables with large uniqueness values were left as single factors. Results:We identified 32 factors, including six constructs derived from factor analyses under the three PARiHS domains. In the evidence domain, four factors described guidelines and clinical pathways. The context domain was broken into three main categories: (i) receptive context (15 factors describing resources, affiliations/networks, formalized policies/practices, decision-making, receptiveness to change); (ii) team functioning (1 factor); and (iii) evaluation/feedback (5 factors). Within facilitation, two factors described facilitator roles and tasks and five captured skills and training. Conclusions:We mapped survey data onto PARiHS domains to identify factors that may be adapted to facilitate ASP uptake. Our model encompasses mostly mutable factors whose relationships with performance outcomes may be explored to optimize antimicrobial use. Our framework also provides an analytical model for determining whether leveraging existing organizational processes can potentially optimize ASP performance.

Objectives

To assess rates of starting or stopping antibiotics across different hospitals.

Methods

We used barcode medication administration data to measure antibiotic use on acute-care wards in 128 Veterans Affairs medical centres (VAMCs) in 2010. A treatment day (TD) was defined as the administration of any antibiotic on a given day. A treatment period (TP) was defined as an interval of inpatient antimicrobial therapy with gaps of ≤1 day in TDs. The rate of starting antibiotics was calculated for inpatients who had not yet started antibiotics, as the number of start events divided by the 'person-time at risk'. The rate of stopping antibiotics was calculated analogously for inpatients that were on antibiotics. Once individuals had stopped antibiotics they were removed from further analysis. Per-day start and stop rates were also calculated for each day of hospitalization.

Results

The hospital mean rate of starting the first TP was 18.1 start events/100 days at risk (range 8.4-25.6/100 days at risk). The mean hospital stopping rate was 21.1 stop events/100 days at risk (range 13.3-29.5/100 days at risk). The ratio of a facility's starting and stopping rates was highly correlated with overall antibiotic use in TDs/1000 patient-days (rs=0.92, P<0.001), while starting and stopping rates individually were only moderately correlated (rs=0.39, P<0.001).

Conclusions

VAMCs with similar antibiotic use showed marked differences in their starting and stopping rates of antibiotics. It may be useful to target empirical therapy when starting rates are high and definitive therapy when stopping rates are low.

Background

Antibiotics are overprescribed for acute respiratory tract infections (ARIs). Guidelines provide criteria to determine which patients should receive antibiotics. We assessed congruence between documentation of ARI diagnostic and treatment practices with guideline recommendations, treatment appropriateness, and outcomes.

Methods

A multicenter quality improvement evaluation was conducted in 28 Veterans Affairs facilities. We included visits for pharyngitis, rhinosinusitis, bronchitis, and upper respiratory tract infections (URI-NOS) that occurred during the 2015-2016 winter season. A manual record review identified complicated cases, which were excluded. Data were extracted for visits meeting criteria, followed by analysis of practice patterns, guideline congruence, and outcomes.

Results

Of 5,740 visits, 4,305 met our inclusion criteria: pharyngitis (n = 558), rhinosinusitis (n = 715), bronchitis (n = 1,155), URI-NOS (n = 1,475), or mixed diagnoses (>1 ARI diagnosis) (n = 402). Antibiotics were prescribed in 68% of visits: pharyngitis (69%), rhinosinusitis (89%), bronchitis (86%), URI-NOS (37%), and mixed diagnosis (86%). Streptococcal diagnostic testing was performed in 33% of pharyngitis visits; group A Streptococcus was identified in 3% of visits. Streptococcal tests were ordered less frequently for patients who received antibiotics (28%) than those who did not receive antibiotics 44%; P < .01). Although 68% of visits for rhinosinusitis had documentation of symptoms, only 32% met diagnostic criteria for antibiotics. Overall, 39% of patients with uncomplicated ARIs received appropriate antibiotic management. The proportion of 30-day return visits for ARI care was similar for appropriate (11%) or inappropriate (10%) antibiotic management (P = .22).

Conclusions

Antibiotics were prescribed in most uncomplicated ARI visits, indicating substantial overuse. Practice was frequently discordant with guideline diagnostic and treatment recommendations.

Background

Antimicrobial stewardship programs (ASPs) have been advocated to improve antimicrobial utilization, but program implementation is variable. Antimicrobial stewardship programs (ASPs) have been advocated to improve antimicrobial utilization, but program implementation is variable.

Objective

To determine associations between ASPs and facility characteristics, and inpatient antimicrobial utilization measures in the Veterans Affairs (VA) system in 2012.

Design

In 2012, VA administered a survey on antimicrobial stewardship practices to designated ASP contacts at VA acute care hospitals. From the survey, we identified 34 variables across 3 domains (evidence, organizational context, and facilitation) that were assessed using multivariable least absolute shrinkage and selection operator regression against 4 antimicrobial utilization measures from 2012: aggregate acute care antimicrobial use, antimicrobial use in patients with non-infectious primary discharge diagnoses, missed opportunities to convert from parenteral to oral antimicrobial therapy, and double anaerobic coverage.

Setting

All 130 VA facilities with acute care services.

Results

Variables associated with at least 3 favorable changes in antimicrobial utilization included presence of postgraduate physician/pharmacy training programs, number of antimicrobial-specific order sets, frequency of systematic de-escalation review, presence of pharmacists and/or infectious diseases (ID) attendings on acute care ward teams, and formal ID training of the lead ASP pharmacist. Variables associated with 2 unfavorable measures included bed size, the level of engagement with VA Antimicrobial Stewardship Task Force online resources, and utilization of antimicrobial stop orders.

Conclusions

Formalization of ASP processes and presence of pharmacy and ID expertise are associated with favorable utilization. Systematic de-escalation review and order set establishment may be high-yield interventions. Journal of Hospital Medicine 2017;12:301-309.

BACKGROUND Antimicrobial stewardship programs (ASPs) are variably implemented. OBJECTIVE To characterize variations of antimicrobial stewardship structure and practices across all inpatient Veterans Affairs facilities in 2012 and correlate key characteristics with antimicrobial usage. DESIGN A web-based survey regarding stewardship activities was administered to each facility's designated contact. Bivariate associations between facility characteristics and inpatient antimicrobial use during 2012 were determined. SETTING Total of 130 Veterans Affairs facilities with inpatient services. RESULTS Of 130 responding facilities, 29 (22%) had a formal policy establishing an ASP, and 12 (9%) had an approved ASP business plan. Antimicrobial stewardship teams were present in 49 facilities (38%); 34 teams included a clinical pharmacist with formal infectious diseases (ID) training. Stewardship activities varied across facilities, including development of yearly antibiograms (122 [94%]), formulary restrictions (120 [92%]), stop orders for antimicrobial duration (98 [75%]), and written clinical pathways for specific conditions (96 [74%]). Decreased antimicrobial usage was associated with having at least 1 full-time ID physician (P=.03), an ID fellowship program (P=.003), and a clinical pharmacist with formal ID training (P=.006) as well as frequency of systematic patient-level reviews of antimicrobial use (P=.01) and having a policy to address antimicrobial use in the context of Clostridium difficile infection (P=.01). Stop orders for antimicrobial duration were associated with increased use (P=.03). CONCLUSIONS ASP-related activities varied considerably. Decreased antibiotic use appeared related to ID presence and certain select practices. Further statistical assessments may help optimize antimicrobial practices. Infect Control Hosp Epidemiol 2016;37:647-654.

Objectives

After the implementation of an active surveillance programme for MRSA in US Veterans Affairs (VA) Medical Centers, there was an increase in vancomycin use. We investigated whether positive MRSA admission surveillance tests were associated with MRSA-positive clinical admission cultures and whether the availability of surveillance tests influenced prescribers' ability to match initial anti-MRSA antibiotic use with anticipated MRSA results from clinical admission cultures.

Methods

Analyses were based on barcode medication administration data, microbiology data and laboratory data from 129 hospitals between January 2005 and September 2010. Hospitalized patient admissions were included if clinical cultures were obtained and antibiotics started within 2 days of admission. Mixed-effects logistic regression was used to examine associations between positive MRSA admission cultures and (i) admission MRSA surveillance test results and (ii) initial anti-MRSA therapy.

Results

Among 569,815 included admissions, positive MRSA surveillance tests were strong predictors of MRSA-positive admission cultures (OR 8.5; 95% CI 8.2-8.8). The negative predictive value of MRSA surveillance tests was 97.6% (95% CI 97.5%-97.6%). The diagnostic OR between initial anti-MRSA antibiotics and MRSA-positive admission cultures was 3.2 (95% CI 3.1-3.4) for patients without surveillance tests and was not significantly different for admissions with surveillance tests.

Conclusions

The availability of nasal MRSA surveillance tests in VA hospitals did not seem to improve the ability of prescribers to predict the necessity of initial anti-MRSA treatment despite the high negative predictive value of MRSA surveillance tests. Prospective trials are needed to establish the safety and effectiveness of using MRSA surveillance tests to guide antibiotic therapy.

OBJECTIVE To examine variation in antibiotic coverage and detection of resistant pathogens in community-onset pneumonia. DESIGN Cross-sectional study. SETTING A total of 128 hospitals in the Veterans Affairs health system. PARTICIPANTS Hospitalizations with a principal diagnosis of pneumonia from 2009 through 2010. METHODS We examined proportions of hospitalizations with empiric antibiotic coverage for methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PAER) and with initial detection in blood or respiratory cultures. We compared lowest- versus highest-decile hospitals, and we estimated adjusted probabilities (AP) for patient- and hospital-level factors predicting coverage and detection using hierarchical regression modeling. RESULTS Among 38,473 hospitalizations, empiric coverage varied widely across hospitals (MRSA lowest vs highest, 8.2% vs 42.0%; PAER lowest vs highest, 13.9% vs 44.4%). Detection rates also varied (MRSA lowest vs highest, 0.5% vs 3.6%; PAER lowest vs highest, 0.6% vs 3.7%). Whereas coverage was greatest among patients with recent hospitalizations (AP for anti-MRSA, 54%; AP for anti-PAER, 59%) and long-term care (AP for anti-MRSA, 60%; AP for anti-PAER, 66%), detection was greatest in patients with a previous history of a positive culture (AP for MRSA, 7.9%; AP for PAER, 11.9%) and in hospitals with a high prevalence of the organism in pneumonia (AP for MRSA, 3.9%; AP for PAER, 3.2%). Low hospital complexity and rural setting were strong negative predictors of coverage but not of detection. CONCLUSIONS Hospitals demonstrated widespread variation in both coverage and detection of MRSA and PAER, but probability of coverage correlated poorly with probability of detection. Factors associated with empiric coverage (eg, healthcare exposure) were different from those associated with detection (eg, microbiology history). Providing microbiology data during empiric antibiotic decision making could better align coverage to risk for resistant pathogens and could promote more judicious use of broad-spectrum antibiotics. Infect Control Hosp Epidemiol 2017;38:937-944.

Objective

To examine how individual steward characteristics (eg, steward role, sex, and specialized training) are associated with their views of antimicrobial stewardship program (ASP) implementation at their institution.

Design

Descriptive survey from a mixed-methods study.

Setting

Two large national healthcare systems; the Veterans' Health Administration (VA) (n = 134 hospitals) and Intermountain Healthcare (IHC; n = 20 hospitals).

Participants

We sent the survey to 329 antibiotic stewards serving in 154 hospitals; 152 were physicians and 177 were pharmacists. In total, 118 pharmacists and 64 physicians from 126 hospitals responded.

Methods

The survey was grounded in constructs of the Consolidated Framework for Implementation Research, and it assessed stewards' views on the development and implementation of antibiotic stewardship programs (ASPs) at their institutions We then examined differences in stewards' views by demographic factors.

Results

Regardless of individual factors, stewards agreed that the ASP added value to their institution and was advantageous to patient care. Stewards also reported high levels of collegiality and self-efficacy. Stewards who had specialized training or those volunteered for the role were less likely to think that the ASP was implemented due to a mandate. Similarly volunteers and those with specialized training felt that they had authority in the antibiotic decisions made in their facility.

Conclusions

Given the importance of ASPs, it may be beneficial for healthcare institutions to recruit and train individuals with a true interest in stewardship.

OBJECTIVE To detail the activities of the Veterans Health Administration (VHA) Antimicrobial Stewardship Initiative and evaluate outcomes of the program. DESIGN Observational analysis. SETTING The VHA is a large integrated healthcare system serving approximately 6 million individuals annually at more than 140 medical facilities. METHODS Utilization of nationally developed resources, proportional distribution of antibiotics, changes in stewardship practices and patient safety measures were reported. In addition, inpatient antimicrobial use was evaluated before and after implementation of national stewardship activities. RESULTS Nationally developed stewardship resources were well utilized, and many stewardship practices significantly increased, including development of written stewardship policies at 92% of facilities by 2015 (P<.05). While the proportional distribution of antibiotics did not change, inpatient antibiotic use significantly decreased after VHA Antimicrobial Stewardship Initiative activities began (P<.0001). A 12% decrease in antibiotic use was noted overall. The VHA has also noted significantly declining use of antimicrobials prescribed for resistant Gram-negative organisms, including carbapenems, as well as declining hospital readmission and mortality rates. Concurrently, the VHA reported decreasing rates of Clostridium difficile infection. CONCLUSIONS The VHA National Antimicrobial Stewardship Initiative includes continuing education, disease-specific guidelines, and development of example policies in addition to other highly utilized resources. While no specific ideal level of antimicrobial utilization has been established, the VHA has shown that improving antimicrobial usage in a large healthcare system may be achieved through national guidance and resources with local implementation of antimicrobial stewardship programs. Infect Control Hosp Epidemiol 2017;38:513-520.