Strategies to contain the emergence of antimicrobial resistance: a systematic review of effectiveness and cost-effectiveness

Cost-effectiveness of point-of-care diagnostics for AMR: a systematic review

BACKGROUND

Antimicrobial resistance (AMR) is a major threat to global health. By 2050, it is forecast that AMR will cause 10 million deaths and cost 100 trillion USD annually. Point-of-care tests (POCTs) may represent a cost-effective approach to reduce AMR.

OBJECTIVES

We systematically reviewed which POCTs addressing AMR have undergone economic evaluation in primary and secondary healthcare globally, how these POCTs have been economically evaluated, and which are cost-effective in reducing antimicrobial prescribing or the burden of AMR. Clinical cost-effectiveness was additionally addressed.

METHODS

This systematic review, accordant with PRISMA guidelines, was pre-registered on PROSPERO (CRD42022315192). MEDLINE, PubMed, Embase, Cochrane Library, and Google Scholar were searched from 2000 to 2023 for relevant publications. Quality assessment was performed using the Consensus of Health Economic Criteria.

RESULTS

The search strategy identified 1421 studies, of which 20 met the inclusion criteria. The most common POCTs assessed were for respiratory infections (n = 10), STIs (n = 3), and febrile patients in low- and middle-income countries (n = 3). All studies assessed costs from a healthcare provider perspective; five additionally considered the societal cost of AMR.Eighteen studies identified POCT strategies that reduced antimicrobial prescribing. Of these, 10 identified POCTs that would be considered cost-effective at a willingness-to-pay (WTP) threshold of £33.80 per antibiotic prescription avoided. Most POCT strategies improved clinical outcomes (n = 14); the remainder were clinically neutral.

CONCLUSIONS

There is evidence that some POCTs are cost-effective in reducing antimicrobial prescribing, with potential concomitant clinical benefits. Such interventions-especially CRP POCTs in both high- and low-income settings-merit further, large-scale clinical evaluation.

Costs-effectiveness and cost components of pharmaceutical and non-pharmaceutical interventions affecting antibiotic resistance outcomes in hospital patients: a systematic literature review

INTRODUCTION

Limited information on costs and the cost-effectiveness of hospital interventions to reduce antibiotic resistance (ABR) hinder efficient resource allocation.

METHODS

We conducted a systematic literature review for studies evaluating the costs and cost-effectiveness of pharmaceutical and non-pharmaceutical interventions aimed at reducing, monitoring and controlling ABR in patients. Articles published until 12 December 2023 were explored using EconLit, EMBASE and PubMed. We focused on critical or high-priority bacteria, as defined by the WHO, and intervention costs and incremental cost-effectiveness ratio (ICER). Following Preferred Reporting Items for Systematic review and Meta-Analysis guidelines, we extracted unit costs, ICERs and essential study information including country, intervention, bacteria-drug combination, discount rates, type of model and outcomes. Costs were reported in 2022 US dollars ($), adopting the healthcare system perspective. Country willingness-to-pay (WTP) thresholds from Woods et al 2016 guided cost-effectiveness assessments. We assessed the studies reporting checklist using Drummond's method.

RESULTS

Among 20 958 articles, 59 (32 pharmaceutical and 27 non-pharmaceutical interventions) met the inclusion criteria. Non-pharmaceutical interventions, such as hygiene measures, had unit costs as low as $1 per patient, contrasting with generally higher pharmaceutical intervention costs. Several studies found that linezolid-based treatments for methicillin-resistant Staphylococcus aureus were cost-effective compared with vancomycin (ICER up to $21 488 per treatment success, all 16 studies' ICERs

CONCLUSION

Robust information on ABR interventions is critical for efficient resource allocation. We highlight cost-effective strategies for mitigating ABR in hospitals, emphasising substantial knowledge gaps, especially in low-income and middle-income countries. Our study serves as a resource for guiding future cost-effectiveness study design and analyses.PROSPERO registration number CRD42020341827 and CRD42022340064.

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Key Words

• Control strategies
• Infections, diseases, disorders, injuries
• Prevention strategies
• Public Health
• Systematic review

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MESH Headings

• Humans
• Methicillin-Resistant Staphylococcus aureus
• Checklist
• Drug Resistance, Microbial
• Hospitals
• Pharmaceutical Preparations

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Grants

• FONDECYT
• Asociación Nacional de Investigación y Desarrollo (ANID)
• Agencia Nacional de Investigación y Desarrollo ANID/FONDAP CIGIDEN
• National Institute for Health Research Health Protection Research Unit

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Affiliation(s)

Kasim Allel Disease Control Department, London School of Hygiene & Tropical Medicine, London, UK Institute for Global Health, University College London, London, UK Department of Health and Community Sciences, University of Exeter, Exeter, UK
María José Hernández-Leal Department of Community, Maternity and Paediatric Nursing, University of Navarra, Pamplona, Spain Millennium Nucleus on Sociomedicine, Santiago, Chile
Nichola R Naylor Department of Health Services Research and Policy, London School of Hygiene & Tropical Medicine, London, UK HCAI, Fungal, AMR, AMU & Sepsis Division, UK Health Security Agency, London, UK
Eduardo A Undurraga Escuela de Gobierno, Pontificia Universidad Catolica de Chile, Santiago, Chile CIFAR Azrieli Global Scholars program, Canadian Institute for Advanced Research, Toronto, Ontario, Canada
Gerard Joseph Abou Jaoude Institute for Global Health, University College London, London, UK
Priyanka Bhandari Disease Control Department, London School of Hygiene & Tropical Medicine, London, UK
Ellen Flanagan Disease Control Department, London School of Hygiene & Tropical Medicine, London, UK
Hassan Haghparast-Bidgoli Institute for Global Health, University College London, London, UK
Koen B Pouwels Nuffield Department of Population Health, University of Oxford, Oxford, UK The National Institute for Health Research Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, University of Oxford, Oxford, UK
Laith Yakob Disease Control Department, London School of Hygiene & Tropical Medicine, London, UK

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A systematic literature review of economic evaluation studies of interventions impacting antimicrobial resistance

BACKGROUND

Antimicrobial resistance (AMR) is accelerated by widespread and inappropriate use of antimicrobials. Many countries, including those in low- and middle- income contexts, have started implementing interventions to tackle AMR. However, for many interventions there is little or no economic evidence with respect to their cost-effectiveness. To help better understand the scale of this evidence gap, we conducted a systematic literature review to provide a comprehensive summary on the value for money of different interventions affecting AMR.

METHODS

A systematic literature review was conducted of economic evaluations on interventions addressing AMR. a narrative synthesis of findings was produced. Systematic searches for relevant studies were performed across relevant databases and grey literature sources such as unpublished studies, reports, and other relevant documents. All identified economic evaluation studies were included provided that they reported an economic outcome and stated that the analysed intervention aimed to affect AMR or antimicrobial use in the abstract. Studies that reported clinical endpoints alone were excluded. Selection for final inclusion and data extraction was performed by two independent reviewers. A quality assessment of the evidence used in the included studies was also conducted.

RESULTS

28,597 articles were screened and 35 articles were identified that satisfied the inclusion criteria. The review attempted to answer the following questions: (1) What interventions to address AMR have been the subject of an economic evaluation? (2) In what types of setting (e.g. high-income, low-income, regions etc.) have these economic evaluations been focused? (3) Which interventions have been estimated to be cost-effective, and has this result been replicated in other settings/contexts? (4) What economic evaluation methods or techniques have been used to evaluate these interventions? (5) What kind and quality of data has been used in conducting economic evaluations for these interventions?

DISCUSSION

The review is one of the first of its kind, and the most recent, to systematically review the literature on the cost-effectiveness of AMR interventions. This review addresses an important evidence gap in the economics of AMR and can assist AMR researchers' understanding of the state of the economic evaluation literature, and therefore inform future research. Systematic review registration PROSPERO (CRD42020190310).

The economic burden of antibiotic resistance: A systematic review and meta-analysis

INTRODUCTION

Antibiotic resistance (ABR) has substantial global public health concerns. This systematic review aimed to synthesise recent evidence estimating the economic burden of ABR, characterised by study perspectives, healthcare settings, study design, and income of the countries.

METHODS

This systematic review included peer-reviewed articles from PubMed, Medline, and Scopus databases, and grey literature on the topic of the economic burden of ABR, published between January 2016 and December 2021. The study was reported in line with 'Preferred Reporting Items for Systematic Review and Meta-Analysis' (PRISMA). Two reviewers independently screened papers for inclusion first by title, then abstract, and then the full text. Study quality was assessed using appropriate quality assessment tools. Narrative synthesis and meta-analyses of the included studies were conducted.

RESULTS

A total of 29 studies were included in this review. Out of these studies, 69% (20/29) were conducted in high-income economies and the remainder were conducted in upper-and-middle income economies. Most of the studies were conducted from a healthcare or hospital perspective (89.6%, 26/29) and 44.8% (13/29) studies were conducted in tertiary care settings. The available evidence indicates that the attributable cost of resistant infection ranges from -US$2,371.4 to +US$29,289.1 (adjusted for 2020 price) per patient episode; the mean excess length of stay (LoS) is 7.4 days (95% CI: 3.4-11.4), the odds ratios of mortality for resistant infection is 1.844 (95% CI: 1.187-2.865) and readmission is 1.492 (95% CI: 1.231-1.807).

CONCLUSION

Recent publications show that the burden of ABR is substantial. There is still a lack of studies on the economic burden of ABR from low-income economies, and lower-middle-income economies, from a societal perspective, and in relation to primary care. The findings of this review may be of value to researchers, policymakers, clinicians, and those who are working in the field of ABR and health promotion.

SYSTEMATIC REVIEW REGISTRATION

CRD42020193886.

A protocol for a systematic literature review of economic evaluation studies of interventions to address antimicrobial resistance

BACKGROUND

Antimicrobial resistance (AMR) is accelerated by the widespread and often indiscriminate use of antimicrobials in humans, animals, and the environment. In 2015, the World Health Organization recognised AMR as one of the top ten global health threats, due to its potential to neutralise humanity's advancements in western medicine by enabling the emergence of new strains of existing pathogens, many of which have no available treatments. Over the past decade, several countries, including those in low- and middle-income contexts, have started implementing interventions to tackle AMR. However, economic evidence regarding the cost-effectiveness of these interventions remains weak. To address this evidence gap, we will conduct a systematic literature review to provide a comprehensive summary on the value for money of different AMR interventions.

METHODS

We aim to conduct a systematic literature review of all available economic evaluations on interventions addressing AMR and will provide a narrative synthesis of our findings. Systematic searches for relevant studies will be performed across all suitable databases as well as in grey literature sources such as unpublished studies, reports, and other relevant documents. All economic evaluation studies will be included as long as they report an economic outcome and have stated that the analysed intervention will reduce antimicrobial resistance or antimicrobial use in the abstract. Those studies reporting clinical endpoints alone will be excluded. Selection for final inclusion and data extraction will be performed by two independent reviewers.

DISCUSSION

The review will be one of the first of its kind, and the most recent, to systematically review literature on the cost-effectiveness of AMR interventions, an important evidence gap in the economics of AMR. The findings will enable policy and decision-makers, particularly in resource-constrained settings, to better use available resources when selecting interventions to address AMR burdens, SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020190310.

Quantitatively evaluating the cross-sectoral and One Health impact of interventions: A scoping review and case study of antimicrobial resistance

BACKGROUND

Current frameworks evaluating One Health (OH) interventions focus on intervention-design and -implementation. Cross-sectoral impact evaluations are needed to more effectively tackle OH-issues, such as antimicrobial resistance (AMR). We aimed to describe quantitative evaluation methods for interventions related to OH and cross-sectoral issues, to propose an explicit approach for evaluating such interventions, and to apply this approach to AMR.

METHODS

A scoping review was performed using WebofScience, EconLit, PubMed and gray literature. Quantitative evaluations of interventions that had an impact across two or more of the human, animal and environment sectors were included. Information on the interventions, methods and outcome measures found was narratively summarised. The information from this review informed the construction of a new approach to OH-related intervention evaluation, which then was applied to the field of AMR.

RESULTS

The review included 90 studies: 73 individual evaluations (from 72 papers) and 18 reviews, with a range of statistical modelling (n = 13 studies), mathematical modelling (n = 53) and index-creation/preference-ranking (n = 14) methods discussed. The literature highlighted the need to (I) establish stakeholder objectives, (II) establish quantifiable outcomes that feed into those objectives, (III) establish agents and compartments that affect these outcomes and (IV) select appropriate methods (described in this review) accordingly. Based on this, an evaluation model for AMR was conceptualised; a decision-tree of intervention options, a compartmental-microeconomic model across sectors and a general-equilibrium (macroeconomic) model are linked. The outcomes of this multi-level model (including cost-utility and Gross Domestic Product impact) can then feed into multi-criteria-decision analyses that weigh respective impact estimates alongside other chosen outcome estimates (for example equity or uncertainty).

CONCLUSION

In conclusion, stakeholder objectives are key in establishing which evaluation methods (and associated outcome measures) should be used for OH-related interventions. The stated multi-level approach also allows for sub-systems to be modelled in succession, where resources are constrained.

The healthcare costs of antimicrobial resistance in Lebanon: a multi-centre prospective cohort study from the payer perspective

Background

Our aim was to examine whether the length of stay, hospital charges and in-hospital mortality attributable to healthcare- and community-associated infections due to antimicrobial-resistant bacteria were higher compared with those due to susceptible bacteria in the Lebanese healthcare settings using different methodology of analysis from the payer perspective .

Methods

We performed a multi-centre prospective cohort study in ten hospitals across Lebanon. The sample size consisted of 1289 patients with documented healthcare-associated infection (HAI) or community-associated infection (CAI). We conducted three separate analysis to adjust for confounders and time-dependent bias: (1) Post-HAIs in which we included the excess LOS and hospital charges incurred after infection and (2) Matched cohort, in which we matched the patients based on propensity score estimates (3) The conventional method, in which we considered the entire hospital stay and allocated charges attributable to CAI. The linear regression models accounted for multiple confounders.

Results

HAIs and CAIs with resistant versus susceptible bacteria were associated with a significant excess length of hospital stay (2.69 days [95% CI,1.5–3.9]; p < 0.001) and (2.2 days [95% CI,1.2–3.3]; p < 0.001) and resulted in additional hospital charges ($1807 [95% CI, 1046–2569]; p < 0.001) and ($889 [95% CI, 378–1400]; p = 0.001) respectively. Compared with the post-HAIs analysis, the matched cohort method showed a reduction by 26 and 13% in hospital charges and LOS estimates respectively. Infections with resistant bacteria did not decrease the time to in-hospital mortality, for both healthcare- or community-associated infections. Resistant cases in the post-HAIs analysis showed a significantly higher risk of in-hospital mortality (odds ratio, 0.517 [95% CI, 0.327–0.820]; p = 0.05).

Conclusion

This is the first nationwide study that quantifies the healthcare costs of antimicrobial resistance in Lebanon. For cases with HAIs, matched cohort analysis showed more conservative estimates compared with post-HAIs method. The differences in estimates highlight the need for a unified methodology to estimate the burden of antimicrobial resistance in order to accurately advise health policy makers and prioritize resources expenditure.

Prevalence and Characteristics of Extended-Spectrum-β-Lactamase-Producing and Carbapenemase-Producing Enterobacteriaceae from Freshwater Fish and Pork in Wet Markets of Hong Kong

Extended-spectrum-β-lactamase-producing Enterobacteriaceae (ESBL-E) and carbapenemase-producing Enterobacteriaceae (CPE) are of global health importance, yet there is a paucity of surveillance studies on food animals in Hong Kong. Here, we report a high prevalence of ESBL-E (ranging from 0.5% to 52.4%) and CPE (0% to 9.9%) from various food animal samples procured from wet markets across Hong Kong. All CPE strains were characterized by whole-genome sequencing and possessed NDM-1 and -5 genes and other resistance determinants. Given the increased resistance profile of these strains, this study highlights the emerging threat of ESBL-E and CPE disseminated in farmed animals. Furthermore, our data enriched our understanding of antibiotic resistance reservoirs from a One Health perspective that can widely spread across various niches, beyond health care settings.

This study identified and characterized extended-spectrum-β-lactamase-producing Enterobacteriaceae (ESBL-E) and carbapenemase-producing Enterobacteriaceae (CPE) from farmed freshwater fish and pig offal procured from the wet markets across Hong Kong. During March 2018 to January 2019, 730 food animal samples, namely, 213 snakehead fish, 198 black carp, and 339 pig organs, were examined. ESBL-E and CPE were isolated from the homogenized samples plated on selective media and identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF-MS). All ESBL-E and CPE strains were tested for antimicrobial susceptibilities. ESBL-E and CPE gene groups were detected by multiplex PCR and bla_{CTX-M-1/-2/-9} group strains were Sanger sequenced for CTX-M types. All CPE isolates were whole-genome sequenced. Isolation of ESBL-E from pig small (52.4%) and large (50%) intestines and tongues (25.1%) was significantly (P < 0.05) more frequent than from snakehead (0.94%) and black carp (0.5%) fish. ESBL-E isolates (n = 171) revealed resistance rates of 16.3%, 29.8%, 35.6%, 53.2%, 55.0%, and 100% to piperacillin-tazobactam, amoxicillin-clavulanate, cefepime, gentamicin, ciprofloxacin, and ampicillin, respectively, whereas CPE (n = 28) were resistant to almost all the antibiotics tested except gentamicin, ciprofloxacin, and fosfomycin. The predominant ESBL gene groups in fishes and pig offals were bla_CTX, where bla_CTX-M-55 was the major subtype in the bla_CTX-M-1 group (64.4% of isolates in the group). bla_CTX-M-14/-17 was the major genotype in the bla_CTX-M-9 group (32.2%). All CPE strains possessed bla_NDM genes. High rates of ESBL-E and CPE were identified in food animals from wet markets of Hong Kong, which may serve as a potential reservoir of antimicrobial-resistant genes and increase the challenges in tackling antimicrobial resistance beyond health care settings.

IMPORTANCE Extended-spectrum-β-lactamase-producing Enterobacteriaceae (ESBL-E) and carbapenemase-producing Enterobacteriaceae (CPE) are of global health importance, yet there is a paucity of surveillance studies on food animals in Hong Kong. Here, we report a high prevalence of ESBL-E (ranging from 0.5% to 52.4%) and CPE (0% to 9.9%) from various food animal samples procured from wet markets across Hong Kong. All CPE strains were characterized by whole-genome sequencing and possessed NDM-1 and -5 genes and other resistance determinants. Given the increased resistance profile of these strains, this study highlights the emerging threat of ESBL-E and CPE disseminated in farmed animals. Furthermore, our data enriched our understanding of antibiotic resistance reservoirs from a One Health perspective that can widely spread across various niches, beyond health care settings.

Quantifying the economic cost of antibiotic resistance and the impact of related interventions: rapid methodological review, conceptual framework and recommendations for future studies

BACKGROUND

Antibiotic resistance (ABR) poses a major threat to health and economic wellbeing worldwide. Reducing ABR will require government interventions to incentivise antibiotic development, prudent antibiotic use, infection control and deployment of partial substitutes such as rapid diagnostics and vaccines. The scale of such interventions needs to be calibrated to accurate and comprehensive estimates of the economic cost of ABR.

METHODS

A conceptual framework for estimating costs attributable to ABR was developed based on previous literature highlighting methodological shortcomings in the field and additional deductive epidemiological and economic reasoning. The framework was supplemented by a rapid methodological review.

RESULTS

The review identified 110 articles quantifying ABR costs. Most were based in high-income countries only (91/110), set in hospitals (95/110), used a healthcare provider or payer perspective (97/110), and used matched cohort approaches to compare costs of patients with antibiotic-resistant infections and antibiotic-susceptible infections (or no infection) (87/110). Better use of methods to correct biases and confounding when making this comparison is needed. Findings also need to be extended beyond their limitations in (1) time (projecting present costs into the future), (2) perspective (from the healthcare sector to entire societies and economies), (3) scope (from individuals to communities and ecosystems), and (4) space (from single sites to countries and the world). Analyses of the impact of interventions need to be extended to examine the impact of the intervention on ABR, rather than considering ABR as an exogeneous factor.

CONCLUSIONS

Quantifying the economic cost of resistance will require greater rigour and innovation in the use of existing methods to design studies that accurately collect relevant outcomes and further research into new techniques for capturing broader economic outcomes.

Projected impact and cost-effectiveness of community-based versus targeted azithromycin administration strategies for reducing child mortality in sub-Saharan Africa

BACKGROUND

Trials of mass drug administration (MDA) of azithromycin (AZM) report reductions in child mortality in sub-Saharan Africa (SSA). AZM targeted to high-risk children may preserve benefit while minimizing antibiotic exposure. We modeled the cost-effectiveness of MDA to children 1-59 months of age, MDA to children 1-5 months of age, AZM administered at hospital discharge, and the combination of MDA and post-discharge AZM.

METHODS AND FINDINGS

Models employed a payer perspective with a 1-year time horizon. Cost-effectiveness was presented as cost per DALY averted and death averted, with probabilistic sensitivity analyses. The model included parameters for macrolide resistance, adverse events, hospitalization, and mortality sourced from published data. Assuming a base-case 1.64% mortality risk among children 1-59 months old, 3.1% among children 1-5 months old, 4.4% mortality risk post-discharge, and 13.5% mortality reduction per trial data, post-discharge AZM would avert ~45,000 deaths, at a cost of $2.84/DALY (95% uncertainty interval [UI]: 1.71-5.57) averted. MDA to only children 1-5 months old would avert ~186,000 deaths at a cost of $4.89/DALY averted (95% UI: 2.88-11.42), MDA to all under-5 children would avert ~267,000 deaths a cost of $14.26/DALY averted (95% UI: 8.72-27.08). Cost-effectiveness decreased with presumed diminished efficacy due to macrolide resistance.

CONCLUSIONS

Targeting AZM to children at highest risk of death may be an antibiotic-sparing and cost-effective, or even cost-saving, strategy to reduce child mortality. However, targeted AZM averts fewer absolute deaths and may not reach all children who would benefit. Any AZM administration decision must consider implications for antibiotic resistance.

Antimicrobial stewardship programs; a two-part narrative review of step-wise design and issues of controversy Part I: step-wise design of an antimicrobial stewardship program

Regardless of one's opinion of antimicrobial stewardship programs (ASPs), it is hardly possible to work in hospital care and not be exposed to the term or its practical effects. Despite the term being relatively new, the number of publications in the field is vast, including several excellent reviews of general and specific aspects. Work in antimicrobial stewardship is complex, and includes not only aspects of infectious disease and microbiology, but also of epidemiology, genetics, behavioural psychology, systems science, economics and ethics, to name a few. This review aims to take several of these aspects and the scientific evidence of antimicrobial stewardship studies and merge them into two questions: How should we design ASPs based on what we know today? And which are the most essential unanswered questions regarding antimicrobial stewardship on a broader scale? This narrative review is written in two separate parts aiming to provide answers to the two questions. This first part is written as a step-wise approach to designing a stewardship intervention based on the pillars of unmet need, feasibility, scientific evidence and necessary core elements. It is written mainly as a guide to someone new to the field. It is sorted into five distinct steps: (a) focusing on designing aims; (b) assessing performance and local barriers to rational antimicrobial use; (c) deciding on intervention technique; (d) practical, tailored design including core element inclusion; and (e) evaluation and sustainability. The second part, published separately, formulates ten critical questions on controversies in the field of antimicrobial stewardship. It is aimed at clinicians and researchers with stewardship experience and strives to promote discussion, not to provide answers.

Critical knowledge gaps and research needs related to the environmental dimensions of antibiotic resistance

There is growing understanding that the environment plays an important role both in the transmission of antibiotic resistant pathogens and in their evolution. Accordingly, researchers and stakeholders world-wide seek to further explore the mechanisms and drivers involved, quantify risks and identify suitable interventions. There is a clear value in establishing research needs and coordinating efforts within and across nations in order to best tackle this global challenge. At an international workshop in late September 2017, scientists from 14 countries with expertise on the environmental dimensions of antibiotic resistance gathered to define critical knowledge gaps. Four key areas were identified where research is urgently needed: 1) the relative contributions of different sources of antibiotics and antibiotic resistant bacteria into the environment; 2) the role of the environment, and particularly anthropogenic inputs, in the evolution of resistance; 3) the overall human and animal health impacts caused by exposure to environmental resistant bacteria; and 4) the efficacy and feasibility of different technological, social, economic and behavioral interventions to mitigate environmental antibiotic resistance.1.

Estimating the burden of antimicrobial resistance: a systematic literature review

Background

Accurate estimates of the burden of antimicrobial resistance (AMR) are needed to establish the magnitude of this global threat in terms of both health and cost, and to paramaterise cost-effectiveness evaluations of interventions aiming to tackle the problem. This review aimed to establish the alternative methodologies used in estimating AMR burden in order to appraise the current evidence base.

Methods

MEDLINE, EMBASE, Scopus, EconLit, PubMed and grey literature were searched. English language studies evaluating the impact of AMR (from any microbe) on patient, payer/provider and economic burden published between January 2013 and December 2015 were included. Independent screening of title/abstracts followed by full texts was performed using pre-specified criteria. A study quality score (from zero to one) was derived using Newcastle-Ottawa and Philips checklists. Extracted study data were used to compare study method and resulting burden estimate, according to perspective. Monetary costs were converted into 2013 USD.

Results

Out of 5187 unique retrievals, 214 studies were included. One hundred eighty-seven studies estimated patient health, 75 studies estimated payer/provider and 11 studies estimated economic burden. 64% of included studies were single centre. The majority of studies estimating patient or provider/payer burden used regression techniques. 48% of studies estimating mortality burden found a significant impact from resistance, excess healthcare system costs ranged from non-significance to $1 billion per year, whilst economic burden ranged from $21,832 per case to over $3 trillion in GDP loss. Median quality scores (interquartile range) for patient, payer/provider and economic burden studies were 0.67 (0.56-0.67), 0.56 (0.46-0.67) and 0.53 (0.44-0.60) respectively.

Conclusions

This study highlights what methodological assumptions and biases can occur dependent on chosen outcome and perspective. Currently, there is considerable variability in burden estimates, which can lead in-turn to inaccurate intervention evaluations and poor policy/investment decisions. Future research should utilise the recommendations presented in this review.

Trial registration

This systematic review is registered with PROSPERO (PROSPERO CRD42016037510).

How externalities impact an evaluation of strategies to prevent antimicrobial resistance in health care organizations

Background

The rates of antimicrobial-resistant organisms (ARO) continue to increase for both hospitalized and community patients. Few resources have been allocated to reduce the spread of resistance on global, national and local levels, in part because the broader economic impact of antimicrobial resistance (i.e. the externality) is not fully considered when determining how much to invest to prevent AROs, including strategies to contain antimicrobial resistance, such as antimicrobial stewardship programs. To determine how best to measure and incorporate the impact of externalities associated with the antimicrobial resistance when making resource allocation decisions aimed to reduce antimicrobial resistance within healthcare facilities, we reviewed the literature to identify publications which 1) described the externalities of antimicrobial resistance, 2) described approaches to quantifying the externalities associated with antimicrobial resistance or 3) described macro-level policy options to consider the impact of externalities. Medline was reviewed to identify published studies up to September 2016.

Main body

An externality is a cost or a benefit associated with one person’s activity that impacts others who did not choose to incur that cost or benefit. We did not identify a well-accepted method of accurately quantifying the externality associated with antimicrobial resistance. We did identify three main methods that have gained popularity to try to take into account the externalities of antimicrobial resistance, including regulation, charges or taxes on the use of antimicrobials, and the right to trade permits or licenses for antimicrobial use. To our knowledge, regulating use of antimicrobials is the only strategy currently being used by health care systems to reduce antimicrobial use, and thereby reduce AROs. To justify expenditures on programs that reduce AROs (i.e. to formally incorporate the impact of the negative externality of antimicrobial resistance associated with antimicrobial use), we propose an alternative approach that quantifies the externalities of antimicrobial use, combining the attributable cost of AROs with time-series analyses showing the relationship between antimicrobial utilization and incidence of AROs.

Conclusion

Based on the findings of this review, we propose a methodology that healthcare organizations can use to incorporate the impact of negative externalities when making resource allocation decisions on strategies to reduce AROs.

Electronic supplementary material

The online version of this article (doi:10.1186/s13756-017-0211-2) contains supplementary material, which is available to authorized users.

What Interventions Should Pharmacists Employ to Impact Health Practitioners’ Prescribing Practices?

Objective:

To determine which interventions are effective in influencing health practitioners’ prescribing practices and explore differences in intervention complexity, setting, sustainability, cost effectiveness, and impact on patient outcomes.

Methods:

A systematic search for English-language systematic reviews was performed in MEDLINE, Cumulative Index of Nursing and Allied Health Literature, EMBASE, and the Cochrane Library from the date of inception to July 2005 using search terms in accordance with Cochrane recommendations. Included reviews were required to clearly report a search strategy, inclusion/exclusion criteria, literature assessment criteria, and methods for synthesizing or summarizing information and references. Two reviewers independently identified studies for inclusion, assessed study quality, and extracted relevant information. Interventions were classified as consistently effective, inconsistently effective, and effectiveness uncertain.

Results:

Thirty-four of 4585 titles reviewed met the inclusion criteria. Quality scores ranged from 70% to 100%. Consistently effective interventions included reminders (manual and computerized), audit and feedback, educational outreach visits, organizational strategies, and patient-mediated interventions. Inconsistently effective interventions included computer decision support systems and educational meetings. Multi-faceted interventions were consistently shown to be more efficacious than single interventions. Limited data precluded exploration of the effects of interventions in different settings, sustainability of effect, cost effectiveness, and patient clinical outcomes.

Conclusions:

Interventions that are most effective for impacting prescribing practice include audit and feedback, reminders, educational outreach visits, and patient-mediated interventions. To maximize impact, pharmacists’ efforts to positively impact prescribing practices should focus on these intervention types rather than relying primarily on passive didactics or dissemination of guidelines.

Methods for estimating the burden of antimicrobial resistance: a systematic literature review protocol

BACKGROUND

Estimates of the burden of antimicrobial resistance (AMR) are needed to ascertain AMR impact, to evaluate interventions, and to allocate resources efficiently. Recent studies have estimated health, cost, and economic burden relating to AMR, with outcomes of interest ranging from drug-bug resistance impact on mortality in a hospital setting to total economic impact of AMR on the global economy. However, recent collation of this information has been largely informal, with no formal quality assessment of the current evidence base (e.g. with predefined checklists). This review therefore aims to establish what perspectives and resulting methodologies have been used in establishing the burden of AMR, whilst also ascertaining the quality of these studies.

METHODS

The literature review will identify relevant literature using a systematic review methodology. MEDLINE, EMBASE, Scopus and EconLit will be searched utilising a predefined search string. Grey literature will be identified by searching within a predefined list of organisational websites. Independent screening of retrievals will be performed in a two-stage process (abstracts and full texts), utilising a pre-defined inclusion and exclusion criteria. Data will be extracted into a data extraction table and descriptive examination will be performed. Study quality will be assessed using the Newcastle-Ottawa scales and the Philips checklists where appropriate. A narrative synthesis of the results will be presented.

DISCUSSION

This review will provide an overview of previous health, cost and economic definitions of burden and the resultant impact of these different definitions on the burden of AMR estimated. The review will also explore the methods that have been used to calculate this burden and discuss resulting study quality. This review can therefore act as a guide to methods for future research in this area.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016037510.

Effects of implementation of an online comprehensive antimicrobial-stewardship program in ICUs: A longitudinal study

BACKGROUND/PURPOSE

The long-term effects of antimicrobial-stewardship programs in the intensive care units (ICUs) have not been adequately examined. We evaluated the impact of an online comprehensive antimicrobial stewardship program (OCASP) on the outcomes of patients in 200-bed medical/surgical ICUs over the course of 11 years.

METHODS

We analyzed the records of adult patients admitted to ICUs during the 5 years before (n = 27,499) and the 6 years after (n = 33,834) implementation of an OCASP. Antimicrobial consumption, expenditures, duration of treatment, incidence of healthcare-associated infections (HAIs), prevalence of HAIs caused by antimicrobial-resistant strains, and crude or sepsis-related mortality of patients were analyzed. Segmented regression analyses of interrupted time series were used to assess the significance of changes in antimicrobial use.

RESULTS

Compared to the patients in the pre-OCASP period, the patients in the post-OCASP period were older, had greater disease severity, longer ICU stays, and were more likely to receive antimicrobials, but had lower antimicrobial expenditures and crude and sepsis-related mortality. The trend of overall antimicrobial use [slope of defined daily dose/1000 patient-days vs. time) increased significantly before OCASP implementation (p < 0.001), but decreased significantly after implementation (p < 0.01). The administration duration of all classes of antibiotics were significantly shorter (p < 0.001) and the incidences of HAIs were significantly lower (p < 0.001) after implementation. However, there was an increase in the proportion of HAIs caused by carbapenem-resistant Acinetobacter baumannii relative to all A. baumannii infections.

CONCLUSION

Implementation of an OCASP in the ICUs reduced antimicrobial consumption and expenditures, but did not compromise healthcare quality.

Antimicrobial Use Control Measures to Prevent and Control Antimicrobial Resistance in US Hospitals

Objective.

Clinical practice guidelines and recommended practices to control use of antibiotics have been published, but the effect of these practices on antimicrobial resistance (AMR) rates in hospitals is unknown. The objective of this study was to examine relationships between antimicrobial use control strategies and AMR rates in a national sample of US hospitals.

Design.

Cross-sectional, stratified study of a nationally representative sample of US hospitals.

Methods.

A survey instrument was sent to the person responsible for infection control at a sample of 670 US hospitals. The outcome was current prevalences of 4 epidemiologically important, drug-resistant pathogens, considered concurrently: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, ceftazidime-resistant Klebsiella species, and quinolone (ciprofloxacin)-resistant Escherichia coli Five independent variables regarding hospital practices were selected from the survey: the extent to which hospitals (1) implement practices recommended in clinical practice guidelines and ensure best practices for antimicrobial use, (2) disseminate information on clinical practice guidelines for antimicrobial use, (3) use antimicrobial-related information technology, (4) use decision support tools, and (5) communicate to prescribers about antimicrobial use. Control variables included the hospitals' number of beds, teaching status, Veterans Affairs status, geographic region, and number of long-term care beds; and the presence of an intensive care unit, a burn unit, or transplant services. A generalized estimating equation modeled all resistance rates simultaneously to identify overall predictors of AMR levels at the facility.

Results.

Completed survey instruments were returned by 448 hospitals (67%). Four antimicrobial control measures were associated with higher prevalence of AMR. Implementation of recommended practices for antimicrobial use (P< .01) and optimization of the duration of empirical antibiotic prophylaxis (P<.01) were associated with a lower prevalence of AMR. Use of restrictive formularies (P = .05) and dissemination of clinical practice guideline information (P<.01) were associated with higher prevalence of AMR. Number of beds and Veterans Affairs status were also associated with higher AMR rates overall.

Conclusions.

Implementation of guideline-recommended practices to control antimicrobial use and optimize the duration of empirical therapy appears to help control AMR rates in US hospitals. A longitudinal study would confirm the results of this cross-sectional study. These results highlight the need for systems interventions and reengineering to ensure more-consistent application of guideline-recommended measures for antimicrobial use.

Emergence of Resistance inPseudomonas aeruginosaandAcinetobacterSpecies After the Use of Antimicrobials for Burned Patients

Objectives:

To evaluate the emergence of resistance ofPseudomonas aeruginosaandAcinetobacterspecies to imipenem, ciprofloxacin, or both after the use of these drugs and to compare resistant with susceptible isolates by molecular typing.

Design:

Cohort study.

Setting:

Burn intensive care unit (ICU) with 4 beds in a tertiary-care university hospital.

Methods:

During 16 months, surveillance cultures were performed for all patients admitted to the ICU. Demographic information was obtained for each patient. Molecular typing was done by pulsed-field gel electrophoresis using restriction enzymes for 71 isolates ofP. aeruginosaandAcinetobacterspecies.

Results:

Thirty-four patients were admitted and 22 were colonized by susceptibleP. aeruginosaorAcinetobacterspecies before they used the antimicrobials. Nine (41%) of these patients had a resistant isolate after antimicrobial use: 5 had used imipenem alone, 1 had used ciprofloxacin, and 3 had used both drugs. The interval between isolation of the susceptible and resistant isolates ranged from 4 to 25 days, but was 10 or more days for 6 patients. Molecular typing revealed that susceptible and resistant isolates from each patient were different and that although there were no predominant clones among susceptible isolates, there was a predominant clone among resistant isolatesof P. aeruginosaandof Acinetobacter.

Conclusions:

Resistance was not due to the acquisition of resistance mechanisms by a previously susceptible strain, but rather to cross-transmission. Although various measures involving antimicrobial use have received great attention, it would seem that practices to prevent cross-transmission are more important in controlling resistance.

The role of healthcare strategies in controlling antibiotic resistance

In an interview in March 2013, the Chief Medical Officer described antibiotic resistance as a 'ticking time bomb' and ranked it along with terrorism on a list of threats to the nation. Her report Infections and the Rise of Antimicrobial Resistance (Department of Health, 2011) highlighted that, while a new infectious disease has been discovered nearly every year over the past three decades, there have been very few new antibiotics developed, leaving our armoury nearly empty. Antibiotic resistance is a universal problem that needs to be tackled by a wide variety of strategies and players. Our approach to tackling resistance to antibiotic agents must therefore also be dynamic. As well as reducing environmental use, we also need to lower antibiotic use in the healthcare setting. Healthcare workers have a huge role to play in combating antibiotic resistance. This article focuses on several issues related to antibiotic resistance, including antibiotic modes of action and the properties that confer resistance on bacteria. It includes information on antibiotic usage and describes current healthcare strategies we can adopt to help reduce the development of resistance.

Collective action and individual choice: rethinking how we regulate narcotics and antibiotics

Governments across the globe have squandered treasure and imprisoned millions of their own citizens by criminalising the use and sale of recreational drugs. But use of these drugs has remained relatively constant, and the primary victims are the users themselves. Meanwhile, antimicrobial drugs that once had the power to cure infections are losing their ability to do so, compromising the health of people around the world. The thesis of this essay is that policymakers should stop wasting resources trying to fight an unwinnable and morally dubious war against recreational drug users, and start shifting their attention to the serious threat posed by our collective misuse of antibiotics.

Antimicrobial resistance: action to combat the rising microbial challenges

Antimicrobial therapy transformed medical practice from a merely diagnosis-focused approach 80 years ago to a treatment-focused approach, saving millions of lives in the years to follow. Today, numerous medical advances made possible by effective antibiotics are being threatened by the relentlessly rising rates of bacteria resistant to all currently available antibiotics. This phenomenon is a consequence of antibiotic misuse, which exerts undue selective pressure on micro-organisms, combined with defective infection control practices that accelerate their spread. Its impact on societies worldwide is immense, resulting in loss of human life and money. An alarming pattern of resistance involving multidrug-resistant and sometimes pandrug-resistant Gram-negative bacteria is currently emerging. In response to the global public health threat posed by antimicrobial resistance (AMR), a number of national and international actions and initiatives have been developed in recent years to address this issue. Although the optimally effective and cost-effective strategy to reduce AMR is not known, a multifaceted approach is most likely to be successful. It should include actions aiming at optimising antibiotic use, strengthening surveillance and infection control, and improving healthcare worker and public education with regard to antibiotics. Research efforts to bring new effective antibiotics to patients need to be fostered in order to negate the consequences of the current lack of antimicrobial therapy options. A holistic view of AMR as well as intersectoral collaboration between human and veterinary medicine is required to best address the problem.

Evaluation of the Do Bugs Need Drugs? program in British Columbia: Can we curb antibiotic prescribing?

OBJECTIVE

Antibiotic resistance is accelerated by the overuse of antibiotics. Do Bugs Need Drugs? is an educational program adapted in British Columbia to target both the public and health care professionals, with the aim of reducing unnecessary prescribing. The current article presents a descriptive evaluation of the impact of the program over the first four years.

METHOD

Program implementation was measured by the amount of educational material distributed and the level of participation in educational sessions. The impact of the program was assessed by measuring changes in knowledge and prescribing habits of participating physicians, and by investigating provincial trends in antibiotic use.

RESULTS

A total of 51,367 children, assisted-living residents and health care professionals have participated in the program since its inception in the fall of 2005. Pre- and postcourse assessments of participating physicians indicated significant improvements in clinical knowledge and appropriate antibiotic treatment of upper respiratory tract infections. Overall rates of antibiotic use in the province have stabilized since 2006. The rates of consumption of fluoroquinolones and macrolides have levelled off since 2005. Utilization rates for acute bronchitis are at the same level as when the program was first implemented, but rates for other acute upper respiratory tract infections of interest have declined.

CONCLUSIONS

The Do Bugs Need Drugs? program significantly improves physician antibiotic prescription decisions and is ecologically associated with desirable change in population antibiotic consumption patterns.

The crisis of no new antibiotics--what is the way forward?

Antibiotic use not only underpins modern medicine, but has brought huge changes to the world, especially in expectations of survival of children into adulthood. The theme of World Health Day, 2011, was "antimicrobial resistance: no action today and no cure tomorrow". The demise of antibacterial drug discovery brings the spectre of untreatable infections. To prevent this crisis immediate action is needed and a new initiative, Antibiotic Action, has been launched. By bringing together communities who need these drugs with academia, health-care professionals, and pharmaceutical companies, this initiative aims to strengthen and enhance academic-industrial partnerships, bring about revision of costly and laborious processes of licensing and regulation of new antibiotics, and address the economics of antimicrobial drugs (cost of use vs profit). A global alliance for antibiotic drug discovery and development would provide a platform for these initiatives.

The impact of a nationwide antibiotic restriction program on antibiotic usage and resistance against nosocomial pathogens in Turkey

PURPOSE

Antimicrobial resistance among microorganisms is a global concern. In 2003, a nationwide antibiotic restriction program (NARP) was released in Turkey. In this study we evaluated the effect of NARP on antibiotic consumption, antimicrobial resistance, and cost.

MATERIALS AND METHODS

The data obtained from all of the four university hospitals, and one referral tertiary-care educational state hospital in Ankara. Antimicrobial resistance profiles of 14,233 selected microorganisms all grown in blood cultures and antibiotic consumption from 2001 to 2005 were analyzed retrospectively.

RESULTS

A negative correlation was observed between the ceftriaxone consumption and the prevalence of ceftriaxone resistant E.coli and Klebsiella spp. (rho:-0.395, p:0.332 and rho:-0.627, p:0.037, respectively). The decreased usage of carbapenems was correlated with decreased carbapenems-resistant Pseudomonas spp. and Acinetobacter spp (rho:0.155, p:0.712 and rho:0.180, p:0.668, respectively for imipenem). Methicillin resistance rates of S.aureus were decreased from 44% to 41%. After two years of NARP 5,389,155.82 USD saving occurred.

CONCLUSION

NARP is effective in lowering the costs and antibiotic resistance.

Antibiotic susceptibility of intra-abdominal infection isolates from Indian hospitals during 2008

A total of 542 clinical isolates of aerobic Gram-negative bacilli from intra-abdominal infections were collected during 2008 from seven hospitals in India participating in the Study for Monitoring Antimicrobial Resistance Trends (SMART). Isolates were from various infection sources, the most common being gall bladder (30.1 %) and peritoneal fluid (31.5 %), and were mostly hospital-associated isolates (70.8 %) as compared to community-acquired (26.9 %). The most frequently isolated pathogens were Escherichia coli (62.7 %), Klebsiella pneumoniae (16.7 %) and Pseudomonas aeruginosa (5.3 %). Extended-spectrum beta-lactamase (ESBL) rates in E. coli and K. pneumoniae were very high, at 67 % and 55 %, respectively. Most isolates exhibited resistance to one or more antibiotics. The most active drugs were generally ertapenem, imipenem and amikacin. However, hospital-acquired isolates in general, as well as ESBL-positive isolates, exhibited lower susceptibilities than community-acquired isolates. Further surveillance monitoring of intra-abdominal isolates from India is recommended.

Diagnosis and management of complicated intra-abdominal infection in adults and children: guidelines by the Surgical Infection Society and the Infectious Diseases Society of America

Evidence-based guidelines for managing patients with intra-abdominal infection were prepared by an Expert Panel of the Surgical Infection Society and the Infectious Diseases Society of America. These updated guidelines replace those previously published in 2002 and 2003. The guidelines are intended for treating patients who either have these infections or may be at risk for them. New information, based on publications from the period 2003-2008, is incorporated into this guideline document. The panel has also added recommendations for managing intra-abdominal infection in children, particularly where such management differs from that of adults; for appendicitis in patients of all ages; and for necrotizing enterocolitis in neonates.

Improved susceptibility of Gram-negative bacteria in an intensive care unit following implementation of a computerized antibiotic decision support system

OBJECTIVES

Emergence of multiresistant Gram-negative organisms in intensive care units (ICUs) throughout the world is a concerning problem. Therefore we undertook a study to follow the resistance patterns of the most common clinically isolated Gram-negative organisms within our ICU following an antibiotic stewardship intervention to evaluate whether a reduction in broad-spectrum antibiotics improves local antibiotic resistance patterns.

METHODS

This prospective study was conducted over a 7 year period within an ICU at a tertiary teaching hospital in Melbourne, Australia. All clinically isolated Gram-negative organisms were identified and extracted from the hospital pathology system. Three monthly antibiograms were created. The pre-interventional period occurred between January 2000 and June 2002 (10 quarters) and the post-interventional period was defined from July 2002 to December 2006 (18 quarters). Segmented linear regression was used to analyse for a difference in the rates of change in susceptibility.

RESULTS

A total of 2838 Gram-negative organisms were isolated from clinical sites from ICU patients during the study period. There was significant improvement in susceptibility of Pseudomonas to imipenem 18.3%/year [95% confidence interval (CI): 4.9-31.6; P = 0.009] and gentamicin 11.6%/year (95% CI: 1.8-21.5; P = 0.02) compared with the pre-intervention trend. Significant changes in the rates of gentamicin and ciprofloxacin susceptibility were also observed in the inducible Enterobacteriaceae group although these were less clinically significant.

CONCLUSIONS

This study demonstrates improved antibiotic susceptibility of ICU Gram-negative isolates including Pseudomonas following an intervention aimed at reducing broad-spectrum antibiotics.

Diagnosis and Management of Complicated Intra-abdominal Infection in Adults and Children: Guidelines by the Surgical Infection Society and the Infectious Diseases Society of America

Evidence-based guidelines for managing patients with intra-abdominal infection were prepared by an Expert Panel of the Surgical Infection Society and the Infectious Diseases Society of America. These updated guidelines replace those previously published in 2002 and 2003. The guidelines are intended for treating patients who either have these infections or may be at risk for them. New information, based on publications from the period 2003–2008, is incorporated into this guideline document. The panel has also added recommendations for managing intra-abdominal infection in children, particularly where such management differs from that of adults; for appendicitis in patients of all ages; and for necrotizing enterocolitis in neonates.

Impact of a restrictive antimicrobial policy on the process and timing of antimicrobial administration

BACKGROUND

In-hospital antimicrobial approval policies are designed to curb the indiscriminant use of antimicrobials. These policies usually require written forms and/or direct requests to an Infectious Disease specialist (or surrogate) prior to release of the antimicrobial. We hypothesized that the approval processes at our institution results in delayed antimicrobial administration.

METHODS

We performed a retrospective cohort study examining the time from order to administration for 25 different antimicrobials ordered "stat." Antimicrobials were classified as restricted (required approval) or unrestricted. We compared these 2 classes to each other both during the daytime (8 AM to 10 PM), when approval is required for restricted antimicrobials, and at night when the first dose of all antimicrobials is exempted. We defined a delay in administration when the medication was given >1 hour from time of order. We separately examined delays of >2 hours.

RESULTS

A higher percentage of >1-hour delays occurred when the antimicrobial was restricted (odds ratio [OR] = 1.49; 95% confidence interval [CI] = 1.23-1.82). Similar results were seen for >2-hour delays (OR = 1.78; 95% CI = 1.39-2.21). During the exempt-from-restriction time period (10 PM to 8 AM), there was no difference between these 2 classes of antimicrobials. Results were unchanged by adjustment for service (medicine vs. surgery vs. other), patient characteristics (age, sex, race), or by weekday vs. weekend.

CONCLUSIONS

Statistically significant delays in stat antimicrobial administration occur in our institution when antimicrobials require preapproval. These findings illustrate the importance of considering clinical efficiency when restrictions are put in place for time-sensitive therapies such as antimicrobials.

Surveillance for antimicrobial resistant organisms: potential sources and magnitude of bias

Surveillance has been recognized as a fundamental component in the control of antimicrobial- resistant infections. Although surveillance data have been widely published and utilized by researchers and decision makers, little attention has been paid to assessment of their validity. We conducted this review in order to identify and explore potential types and magnitude of bias that may influence the validity or interpretation of surveillance data. Six main potential areas were assessed. These included bias related to use of inadequate or inappropriate (1) denominator data, (2) case definitions, and (3) case ascertainment; (4) sampling bias; (5) failure to deal with multiple occurrences, and (6) those related to laboratory practice and procedures. The magnitude of these biases varied considerably for the above areas within different study populations. There are a number of potential biases that should be considered in the methodological design and interpretation of antimicrobial-resistant organism surveillance.

Measuring appropriate use of antibiotics in pyelonephritis in Belgian hospitals

Inappropriate use of antibiotics can induce antibiotic resistance, treatment failure, increased costs and even mortality. We developed a methodology for measuring guideline compliance of hospital antibiotic prescriptions in community-acquired acute pyelonephritis in Belgium. The claims and clinical data of all Belgian hospitalizations for community-acquired acute pyelonephritis were extracted from a nationwide administrative database. In a clinically homogeneous subset of patients, the percentage of patients who received a guideline-compliant prescription was calculated according to prescription guidelines disseminated in Belgium. In the group of non-pregnant adult female patients, 31% of the prescriptions were not in strict compliance with the guideline. Interhospital variability ranged from 0% to 100% compliance. We conclude that administrative databases can be used to analyze antibiotic prescription behavior in hospitals for homogeneous and clinically relevant patient groups. The interhospital variability observed in Belgian hospitals indicate that there is a clear room for improvement.

Impact of a multidisciplinary approach on antibiotic consumption, cost and microbial resistance in a Czech hospital

OBJECTIVE

The study objective was to evaluate the impact of a restrictive antibiotic policy, efficacy of inpatient therapeutic and prophylactic antibiotic regimens and susceptibility patterns of infecting bacteria in 2000-2004.

SETTING

A 500-bed general hospital in the Czech Republic.

METHOD

A retrospective computerized survey of antibiotic prescribing practices over a five-year period 2000-2004, using medical records and laboratory data from the hospital information system (HIS).

MAIN OUTCOME MEASURE

Consumption of antibiotics expressed in defined daily doses (DDDs) and Euros per 1,000 bed days. Resistance to antibiotics, average length of hospital stay, rate of inpatients treated with antibiotics, number of nosocomial infections per 1,000 bed days, median length of hospital stay and total mortality.

RESULTS

Due to a restrictive antibiotic policy implemented in 2002, the use of several antibiotics in 2003 was significantly reduced but the consumption of several other antibiotics rose in 2003. In comparison with 2001 the cost of antibiotic agents (in Euro per 1,000 inpatient days) fell significantly by 31% in 2003 Euro 969.07 vs. Euro 671.34). The hospital saved about Euro 29,288 after the first year of implementation of the new antibiotic policy. The use of restricted antibiotics increased by 8%; however, the expenditure decreased by 26%. For non-restricted antibiotics, the use and expenditure decreased by 71% and 41%, respectively. Consequently, a net reduction of 55% Euro 804.36 vs. Euro 359.36) was achieved.

CONCLUSION

The intervention was effective in reducing the use and cost of antibiotics. The HIS is a helpful tool for observing and evaluating the impacts of the measures taken and can be used for assessment of pharmacotherapy outcomes.

Short-term effect of antibiotic control policy on the usage patterns and cost of antimicrobials, mortality, nosocomial infection rates and antibacterial resistance

OBJECTIVES

In 2003 Turkish government released a new budget application instruction for regulating the usage of parenteral antibiotics inside and outside of the hospitals. In this study it was aimed to evaluate the effect of this instruction on the overall usage of restricted antibiotics, their cost, overall mortality, bacterial resistance patterns and nosocomial infection rates in intensive care units (ICUs) of our setting for March-October 2002 and March-October 2003 periods.

METHODS AND RESULTS

Overall daily defined dose/1000 patients/day of restricted drugs decreased, whereas unrestricted drugs increased significantly after the instruction. The cost of all analysed drugs in 2003 period was 540,303USD (-19.6%) less than 2002 period. Nosocomial infection rates in ICUs decreased significantly (p<0.05). When all microbiologically confirmed nosocomial bacteremia cases during the study period were analysed, amoxycilline/clavulanate, ciprofloxacin, cefuroxime, cefotaxime, piperacilline/tazobactam resistance and ESBL rate in Klebsiella pneumoniae decreased significantly (p<0.05). Amikacin resistance in Escherichia coli and Acinetobacter baumannii increased significantly (p<0.05).

CONCLUSION

Antibiotic control is one of the most important and significant ways to save money, and to prevent antibacterial resistance.

A review of antimicrobial control strategies in hospitalized and ambulatory pediatric populations

Antimicrobial resistance is a growing crisis in healthcare. Various antimicrobial stewardship strategies have been used to control antibiotic use in efforts to reduce antibiotic resistance. We conducted a systematic review of antimicrobial stewardship programs in pediatric settings. Twenty-eight published studies met inclusion criteria. The majority (21 of 28) of studies had positive outcomes, but only 6 measured the impact of interventions on antimicrobial resistance. Prescriber education for a specific diagnosis (eg, otitis media) was the most effective intervention in the outpatient setting. Ancillary laboratory tests (eg, rapid diagnostic assays for viral pathogens) were most effective in the inpatient setting. Most studies had moderate to high risk of bias, mainly because of selection bias, inadequate preintervention data for time series analysis, and contamination between treatment groups. To date, there are a limited number of studies assessing antimicrobial stewardship in pediatric settings and these have heterogeneous study designs. Thus, it is difficult to determine the most effective interventions. Future studies should be designed to overcome the biases encountered in current publications.

Relationship of Antimicrobial Control Policies and Hospital and Infection Control Characteristics to Antimicrobial Resistance Rates

• Background Antibiotic misuse and noncompliance with infection control precautions have contributed to increasing levels of antimicrobial resistance in hospitals.

• Objectives To assess the extent to which resistance is monitored in infection control programs and to correlate resistance rates with characteristics of antimicrobial control policies, provider attitudes and practices, and systems-level indicators of implementation of the hand hygiene guideline of the Centers for Disease Control and Prevention.

• MethodsAn on-site survey of intensive care unit staff and infection control directors of 33 hospitals in the United States was conducted. The following data were collected: antimicrobial control policies; rates during the previous 12 months of methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and ceftazidime-resistant Klebsiella pneumoniae; an implementation score of systems-level efforts to implement the guideline; staff attitudes toward practice guidelines; and observations of staff hand hygiene. Variables associated with resistance rates were examined for independent effects by using logistic regression.

• ResultsResistance rates for S aureus, enterococci, and K pneumoniae were 52.5%, 18.2%, and 16.0%, respectively. Ten (30.3%) hospitals had an antibiotic control policy. No statistically significant correlation was observed between staff attitudes toward practice guidelines, observed hand hygiene behavior, or having an antibiotic use policy and resistance rates. In logistic regression analysis, higher scores on measures of systems-level efforts to implement the guideline were associated with lower rates of resistant S aureus and enterococci (P=.046).

• Conclusions Organizational-level factors independent of the practices of individual clinicians may be associated with rates of antimicrobial resistance.

A macroeconomic approach to evaluating policies to contain antimicrobial resistance: a case study of methicillin-resistant Staphylococcus aureus (MRSA)

BACKGROUND

Antimicrobial resistance (AMR) is, at least in part, associated with high antimicrobial usage and causes increased morbidity, mortality and healthcare costs. However, policies to contain AMR focus on 'micro' interventions - typically in one institution (usually a hospital). Furthermore, in evaluating these interventions, economists tend to concentrate on the economic impact to the healthcare sector alone, which may give an incorrect estimation of the social costs and benefits of a disease or intervention.

METHODS

This study outlines and illustrates a macroeconomic approach to tackling AMR through the evaluation of three 'macro' policies: regulation, permits and taxes/charges. In addition to effects on the healthcare sector, the effect of AMR (and these three policies to contain it) on labour productivity, GDP, household income, government transfers, tax revenues, unemployment, inflation and social services are estimated for the UK using the specific context of methicillin-resistant Staphylococcus aureus (MRSA).

RESULTS

AMR is likely to have a far greater impact on the national economy than would be estimated by concentrating on the healthcare sector alone.

CONCLUSION

The permit system appears to offer the most efficient 'solution' to optimising antimicrobial consumption and, hence, reducing the development of resistance.

Assessing the macroeconomic impact of a healthcare problem: the application of computable general equilibrium analysis to antimicrobial resistance

There is a positive relationship between the health of a nation and its economic prosperity. However, in evaluating health care, economists typically concentrate on the economic impact only to the health (care) sector, which may mis-specify the social costs and benefits of a disease or intervention. This paper demonstrates the value of using a macroeconomic approach to modelling a major health problem, using the context of antimicrobial resistance and the application of the computable general equilibrium technique. This approach is described in detail and its 'added value' demonstrated in the case of AMR.

Antimicrobial resistance in developing countries. Part II: strategies for containment

The growing threat from resistant organisms calls for concerted action to prevent the emergence of new resistant strains and the spread of existing ones. Developing countries have experienced unfavourable trends in resistance-as detailed in part I, published last month--and implementation of many of the containment strategies recommended by WHO is complicated by universal, as well as developing country-specific, factors. The control of selective pressure for resistance could potentially be addressed through educational and other interventions for orthodox and unorthodox prescribers, distributors, and consumers of antimicrobials. At national levels, the implementation of drug use strategies--eg, combination therapy or cycling--may prove useful to lengthen the lifespan of existing and future agents. Programmes such as the Integrated Management of Childhood Illnesses (IMCI) and directly observed short-course therapy (DOTS) for tuberculosis are prescriber-focused and patient-focused, respectively, and have both been shown to positively influence factors that contribute to the selective pressure that affects resistance. The institution of interventions to prevent the transmission of infectious diseases could also lead to beneficial effects on the prevalence of resistance, as has vaccination against Haemophilus influenzae type B and Streptococcus pneumoniae. There has been an upsurge in the number of organisations and programmes that directly address issues of resistance, and collaboration could be one way to stem the dire trend. Additional factors such as unregulated drug availability, inadequate antimicrobial drug quality assurance, inadequate surveillance, and cultures of antimicrobial abuse must be addressed to permit a holistic strategy for resistance control.

Controlled Trials to Improve Antibiotic Utilization: A Systematic Review of Experience, 1984–2004

STUDY OBJECTIVES

To review the effectiveness of interventions designed to improve antibiotic prescribing patterns in clinical practice and to draw inferences about the most practical methods for optimizing antibiotic utilization in hospital and ambulatory settings.

METHODS

A literature search using online databases for the years 1975-2004 identified controlled trials of strategies for improving antibiotic utilization. Due to variation in study settings and design, quantitative meta-analysis was not feasible. Therefore, a qualitative literature review was conducted.

RESULTS

Forty-one controlled trials met the search criteria. Interventions consisted of education, peer review and feedback, physician participation, rewards and penalties, administrative methods, and combined approaches. Social marketing directed at patients and prescribers was effective in varying contexts, as was implementation of practice guidelines. Authorization systems with structured order entry, formulary restriction, and mandatory consultation were also effective. Peer review and feedback were more effective when combined with dissemination of relevant information or social marketing than when used alone.

CONCLUSIONS

Several practices were effective in improving antibiotic utilization: social marketing, practice guidelines, authorization systems, and peer review and feedback. Online systems providing clinical information, structured order entry, and decision support may be the most promising approach. Further studies, including economic analyses, are needed to confirm or refute this hypothesis.

Antimicrobial resistance: cost and containment

There is growing evidence that antimicrobial resistance causes serious consequences for individuals as well as leading to increased healthcare costs. The containment of resistance is therefore a policy problem which will impact on all health systems in the next few years. Unfortunately, there is, as yet, no definitive evidence suggesting that particular control measures are successful in containing either the emergence or transmission of antimicrobial resistance. Furthermore, few studies contain information about costs and even where there is such information it is generally inadequate because of the narrow perspectives from which analyses are conducted. In part, this is due to methodological problems associated with the inclusion of cost data: measuring and valuing what are often intangible costs; identifying costs associated with organizational change; and accounting for interaction between costs at levels from the individual to the international. Good quality research, including both economic evaluation and comprehensive economic modelling, is required to determine the most cost-effective combination of strategies to pursue in combating resistance, and to find ways around these methodological difficulties.

Methicillin-resistant Staphylococcus aureus infections in ICU patients

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections in patients admitted to the intensive care unit has dramatically increased in recent years, with an associated increase in morbidity and mortality and the costs of caring for patients with MRSA infections. Although indiscriminate and inappropriate use of antibiotics has contributed to this phenomenon, horizontal transmission of MRSA between patients and health care providers is the principal cause of this observed increase. This article discusses the pathogenesis, epidemiology, treatment, and prevention of MRSA infections in critically ill patients.

A view on antimicrobial resistance in developing countries and responsible risk factors

Antimicrobial resistance is one of the biggest challenges facing global public health. Although antimicrobial drugs have saved many lives and eased the suffering of many millions, poverty, ignorance, poor sanitation, hunger and malnutrition, inadequate access to drugs, poor and inadequate health care systems, civil conflicts and bad governance in developing countries have tremendously limited the benefits of these drugs in controlling infectious diseases. The development of resistance in the responsible pathogens has worsened the situation often with very little resource to investigate and provide reliable susceptibility data on which rational treatments can be based as well as means to optimise the use of antimicrobial agents. The emergence of multi-drug-resistant isolates in tuberculosis, acute respiratory infections and diarrhoea, often referred to as diseases of poverty, has had its greatest toll in developing countries. The epidemic of HIV/AIDS, with over 30 million cases in developing countries, has greatly enlarged the population of immunocompromised patients. The disease has left these patients at great risk of numerous infections and even greater risks of acquiring highly resistant organisms during long periods of hospitalisation. This review discusses antimicrobial resistance in developing countries and the risk factors responsible.