Editorial Commentary: A Chance to Change the Paradigm of Outcome Assessment of Antimicrobial Stewardship Programs

A desirability of outcome ranking (DOOR) for periprosthetic joint infection - a Delphi analysis

Background: Treatment outcomes in studies on prosthetic joint infection are generally assessed using a dichotomous outcome relating to treatment success or failure. These outcome measures neither include patient-centred outcome measures including joint function and quality of life, nor do they account for adverse effects of treatment. A desirability of outcome ranking (DOOR) measure can include these factors and has previously been proposed and validated for other serious infections. We aimed to develop a novel DOOR for prosthetic joint infections (PJIs). Methods: The Delphi method was used to develop a DOOR for PJI research. An international working group of 18 clinicians (orthopaedic surgeons and infectious disease specialists) completed the Delphi process. The final DOOR comprised the dimensions established to be most important by consensus with > 75  % of participant agreement. Results: The consensus DOOR comprised four main dimensions. The primary dimension was patient-reported joint function. The secondary dimensions were infection cure and mortality. The final dimension of quality of life was selected as a tie-breaker. Discussion: A desirability of outcome ranking for periprosthetic joint infection has been proposed. It focuses on patient-centric outcome measures of joint function, cure and quality of life. This DOOR provides a multidimensional assessment to comprehensively rank outcomes when comparing treatments for prosthetic joint infection.

Seven-versus 14-day course of antibiotics for the treatment of bloodstream infections by Enterobacterales: a randomized, controlled trial

OBJECTIVE

To prove that 7-day courses of antibiotics for bloodstream infections caused by members of the Enterobacterales (eBSIs) allow a reduction in patients' exposure to antibiotics while achieving clinical outcomes similar to those of 14-day schemes.

METHODS

A randomized trial was performed. Adult patients developing eBSI with appropriate source control were assigned to 7 or 14 days of treatment, and followed 28 days after treatment cessation; treatments could be resumed whenever necessary. The primary endpoint was days of treatment at the end of follow-up. Clinical outcomes included clinical cure, relapse of eBSI and relapse of fever. A superiority margin of 3 days was set for the primary endpoint, and a non-inferiority margin of 10% was set for clinical outcomes. Efficacy and safety were assessed together with a DOOR/RADAR (desirability of outcome ranking and response adjusted for duration of antibiotic risk) analysis.

RESULTS

248 patients were assigned to 7 (n = 119) or 14 (n = 129) days of treatment. In the intention-to-treat analysis, median days of treatment at the end of follow-up were 7 and 14 days (difference 7, 95%CI 7-7). The non-inferiority margin was also met for clinical outcomes, except for relapse of fever (-0.2%, 95%CI -10.4 to 10.1). The DOOR/RADAR showed that 7-day schemes had a 77.7% probability of achieving better results than 14-day treatments.

CONCLUSIONS

7-day schemes allowed a reduction in antibiotic exposure of patients with eBSI while achieving outcomes similar to those of 14-day schemes. The possibility of relapsing fever in a limited number of patients, without relevance to final outcomes, may not be excluded, but was overcome by the benefits of shortening treatments.

Impact of unit-specific metrics and prescribing tools on a family medicine ward

Objective:

Prescribing metrics, cost, and surrogate markers are often used to describe the value of antimicrobial stewardship (AMS) programs. However, process measures are only indirectly related to clinical outcomes and may not represent the total effect of an intervention. We determined the global impact of a multifaceted AMS initiative for hospitalized adults with common infections.

Design:

Single center, quasi-experimental study.

Methods:

Hospitalized adults with urinary, skin, and respiratory tract infections discharged from family medicine and internal medicine wards before (January 2017–June 2017) and after (January 2018–June 2018) an AMS initiative on a family medicine ward were included. A series of AMS-focused initiatives comprised the development and dissemination of: handheld prescribing tools, AMS positive feedback cases, and academic modules. We compared the effect on an ordinal end point consisting of clinical resolution, adverse drug events, and antimicrobial optimization between the preintervention and postintervention periods.

Results:

In total, 256 subjects were included before and after an AMS intervention. Excessive durations of therapy were reduced from 40.3% to 22% (P < .001). Patients without an optimized antimicrobial course were more likely to experience clinical failure (OR, 2.35; 95% CI, 1.17–4.72). The likelihood of a better global outcome was greater in the family medicine intervention arm (62.0%, 95% CI, 59.6–67.1) than in the preintervention family medicine arm.

Conclusion:

Collaborative, targeted feedback with prescribing metrics, AMS cases, and education improved global outcomes for hospitalized adults on a family medicine ward.

Optimizing design of research to evaluate antibiotic stewardship interventions: consensus recommendations of a multinational working group

BACKGROUND

Antimicrobial stewardship interventions and programmes aim to ensure effective treatment while minimizing antimicrobial-associated harms including resistance. Practice in this vital area is undermined by the poor quality of research addressing both what specific antimicrobial use interventions are effective and how antimicrobial use improvement strategies can be implemented into practice. In 2016 we established a working party to identify the key design features that limit translation of existing research into practice and then to make recommendations for how future studies in this field should be optimally designed. The first part of this work has been published as a systematic review. Here we present the working group's final recommendations.

METHODS

An international working group for design of antimicrobial stewardship intervention evaluations was convened in response to the fourth call for leading expert network proposals by the Joint Programming Initiative on Antimicrobial Resistance (JPIAMR). The group comprised clinical and academic specialists in antimicrobial stewardship and clinical trial design from six European countries. Group members completed a structured questionnaire to establish the scope of work and key issues to develop ahead of a first face-to-face meeting that (a) identified the need for a comprehensive systematic review of study designs in the literature and (b) prioritized key areas where research design considerations restrict translation of findings into practice. The working group's initial outputs were reviewed by independent advisors and additional expertise was sought in specific clinical areas. At a second face-to-face meeting the working group developed a theoretical framework and specific recommendations to support optimal study design. These were finalized by the working group co-ordinators and agreed by all working group members.

RESULTS

We propose a theoretical framework in which consideration of the intervention rationale the intervention setting, intervention features and the intervention aims inform selection and prioritization of outcome measures, whether the research sets out to determine superiority or non-inferiority of the intervention measured by its primary outcome(s), the most appropriate study design (e.g. experimental or quasi- experimental) and the detailed design features. We make 18 specific recommendation in three domains: outcomes, objectives and study design.

CONCLUSIONS

Researchers, funders and practitioners will be able to draw on our recommendations to most efficiently evaluate antimicrobial stewardship interventions.

The quality of studies evaluating antimicrobial stewardship interventions: a systematic review

BACKGROUND

Antimicrobial stewardship aims to optimize antibiotic use and minimize selection of antimicrobial resistance. The methodological quality of published studies in this field is unknown.

AIMS

Our objective was to perform a comprehensive systematic review of antimicrobial stewardship research design and identify features which limit validity and translation of research findings into clinical practice.

SOURCES

The following online database was searched: PubMed.

STUDY ELIGIBILITY CRITERIA

Studies published between January 1950 and January 2017, evaluating any antimicrobial stewardship intervention in the community or hospital setting, without restriction on study design or outcome.

CONTENT

We extracted data on pre-specified design quality features and factors that may influence design choices including (1) clinical setting, (2) age group studied, (3) when the study was conducted, (4) geographical region, and (5) financial support received. The initial search yielded 17 382 articles; 1008 were selected for full-text screening, of which 825 were included. Most studies (675/825, 82%) were non-experimental; 104 (15%) used interrupted time series analysis, 41 (6%) used external controls, and 19 (3%) used both. Studies in the community setting fulfilled a median of five out of 10 quality features (IQR 3-7) and 3 (IQR 2-4) in the hospital setting. Community setting studies (25%, 205/825) were significantly more likely to use randomization (OR 5.9; 95% CI 3.8-9.2), external controls (OR 5.6; 95% CI 3.6-8.5), and multiple centres (OR 10.5; 95% CI 7.1-15.7). From all studies, only 48% (398/825) reported clinical and 23% (190/825) reported microbiological outcomes. Quality did not improve over time.

IMPLICATIONS

Overall quality of antimicrobial stewardship studies is low and has not improved over time. Most studies do not report clinical and microbiological outcome data. Studies conducted in the community setting were associated with better quality. These limitations should inform the design of future stewardship evaluations so that a robust evidence base can be built to guide clinical practice.

Expanding Existing Antimicrobial Stewardship Programs in Pediatrics: What Comes Next

The prevalence of pediatric antimicrobial stewardship programs (ASPs) is increasing in acute care facilities across the United States. Over the past several years, the evidence base used to inform effective stewardship practices has expanded, and regulatory interest in stewardship programs has increased. Here, we review approaches for established, hospital-based pediatric ASPs to adapt and report standardized metrics, broaden their reach to specialized populations, expand to undertake novel stewardship initiatives, and implement rapid diagnostics to continue their evolution in improving antimicrobial use and patient outcomes.

Fundamentals and Catalytic Innovation: The Statistical and Data Management Center of the Antibacterial Resistance Leadership Group

The Statistical and Data Management Center (SDMC) provides the Antibacterial Resistance Leadership Group (ARLG) with statistical and data management expertise to advance the ARLG research agenda. The SDMC is active at all stages of a study, including design; data collection and monitoring; data analyses and archival; and publication of study results. The SDMC enhances the scientific integrity of ARLG studies through the development and implementation of innovative and practical statistical methodologies and by educating research colleagues regarding the application of clinical trial fundamentals. This article summarizes the challenges and roles, as well as the innovative contributions in the design, monitoring, and analyses of clinical trials and diagnostic studies, of the ARLG SDMC.

Clinical research in critical care. Difficulties and perspectives

In the field of Intensive Care Medicine, improved survival has resulted from better patient care, the early detection of clinical deterioration, and the prevention of iatrogenic complications, while research on new treatments has been followed by an overwhelming number of disappointments. The origins of these fiascos must be sought in the conjunction of methodological problems - common to other disciplines - and the particularities of critically ill patients. The present article discusses both aspects and suggests some options for progress.

The 2016 Garrod Lecture: The role of the healthcare epidemiologist in antimicrobial chemotherapy-a view from the USA

Antimicrobial chemotherapy now spans 80 years and four generations. The healthcare epidemiologist has an important role to play in this field. Efforts focus in three areas: (i) minimizing the transmission of antimicrobial-resistant bacteria in healthcare settings (infection control); (ii) optimizing use of currently available antibacterial drugs (antibiotic stewardship); and (iii) recognizing and responding to opportunities for new drug development. For each area, the epidemiologist provides data that address four practical questions-'What is the problem?', 'What should be done?', 'Is it being done?' and 'Is it working?'. A team approach is crucial to acting on the epidemiological data. Examples are presented to illustrate different roles of the epidemiologist, and tools and measures that have been developed to address some problems of current importance. Monitoring of quality, integrity and security of data remains a major focus. The epidemiologist will continue to have a key role in antimicrobial chemotherapy.

Appropriate endpoints for evaluation of new antibiotic therapies for severe infections: a perspective from COMBACTE's STAT-Net

PURPOSE

In this era of rising antimicrobial resistance, slowly refilling antibiotic development pipelines, and an aging population, we need to ensure that randomized clinical trials (RCTs) determine the added benefit of new antibiotic agents effectively and in a valid way, especially for severely ill patients. Unfortunately, universally accepted endpoints for the evaluation of new drugs in severe infections are lacking.

METHODS

We review and discuss the current practices and challenges regarding endpoints in RCTs in this field and propose novel approaches.

RESULTS

Usual endpoints actually recommended for drug development suffer from important flaws. Mortality requires large sample size and only partly related to the infectious process. Clinical cure rate is highly subjective in critically ill patients where symptoms may be related to other intercurrent events. Currently, composite endpoints, hierarchical nested designs, and competing risks analysis seem to be the most promising new tools for designing and analyzing clinical trials in this area, although they require further validation.

CONCLUSION

Regulatory authorities, pharmaceutical companies, and clinicians need to agree on the most appropriate clinical endpoints for severe infections to ensure efficient approval of new, effective antibiotic agents.

Good epidemiological practice: a narrative review of appropriate scientific methods to evaluate the impact of antimicrobial stewardship interventions

AIMS

In this narrative review, we provide a framework for assessing the quality of evidence provided by studies investigating antimicrobial stewardship (AMS) interventions, and inform the design and planning stage for future AMS evaluation studies to determine the best strategies to keep antimicrobial resistance at bay.

SOURCES

Cochrane/Pubmed.

CONTENT

As AMS is mostly applied in a complex, real-world setting, bias and random time effects can jeopardize the validity of causal inference. The most important risks include simultaneously implemented infection prevention strategies and regression to the mean. Inclusion of homogeneous intervention and control arms, through randomization of the intervention, can limit these risks. However, contamination can play an important role for AMS; therefore, randomization at cluster-level, instead of randomization at individual-level, is recommended. It can be challenging to identify enough representative clusters, and implementation of a cluster-RCT (cRCT) can be costly. Controlled interrupted time series (ITS) design has a high validity as well, and is relatively straightforward to implement, although time-varying confounding should be considered. Independent of the study design, it is crucial to include multiple process, clinical outcome, microbiological and financial measures, to be able to detect possible, unintended consequences.

IMPLICATIONS

Future studies assessing the impact of new AMS strategies should produce compelling evidence by opting for cRCTs, or ITS including a control arm. Furthermore, a holistic view of intended and unintended consequences should be reported, and a detailed process evaluation should be provided to adequately inform implementation of successful AMS strategies to battle the rising burden of AMR.

Response Adjusted for Days of Antibiotic Risk (RADAR): evaluation of a novel method to compare strategies to optimize antibiotic use

OBJECTIVES

The Response Adjusted for Days of Antibiotic Risk (RADAR) statistic was proposed to improve the efficiency of trials comparing antibiotic stewardship strategies to optimize antibiotic use. We studied the behaviour of RADAR in a non-inferiority trial in which a β-lactam monotherapy strategy (n = 656) was non-inferior to fluoroquinolone monotherapy (n = 888) for patients with moderately severe community-acquired pneumonia.

METHODS

Patients were ranked according to clinical outcome, using five or eight categories, and antibiotic use. RADAR was calculated as the probability that the β-lactam group had a more favourable ranking than the fluoroquinolone group. To investigate the sensitivity of RADAR to detrimental clinical outcome we simulated increasing rates of 90-day mortality in the β-lactam group and performed the RADAR and non-inferiority analysis.

RESULTS

The RADAR of the β-lactam group compared with the fluoroquinolone group was 60.3% (95% CI 57.9%-62.7%) using five and 58.4% (95% CI 56.0%-60.9%) using eight clinical outcome categories, all in favour of β-lactam. Sample sizes for RADAR were 38% (250/653) and 89% (580/653) of the non-inferiority sample size calculation, using five or eight clinical outcome categories, respectively. With simulated mortality rates, loss of non-inferiority of the β-lactam group occurred at a relative risk of 1.125 in the conventional analysis, whereas using RADAR the β-lactam group lost superiority at a relative risk of mortality of 1.25 and 1.5, with eight and five clinical outcome categories, respectively.

CONCLUSIONS

RADAR favoured β-lactam over fluoroquinolone therapy for community-acquired pneumonia. Although RADAR required fewer patients than conventional non-inferiority analysis, the statistic was less sensitive to detrimental outcomes.

Using Outcomes to Analyze Patients Rather than Patients to Analyze Outcomes: A Step toward Pragmatism in Benefit:risk Evaluation

In the future, clinical trials will have an increased emphasis on pragmatism, providing a practical description of the effects of new treatments in realistic clinical settings. Accomplishing pragmatism requires better summaries of the totality of the evidence in ways that clinical trials consumers---patients, physicians, insurers---find transparent and allow for informed benefit:risk decision-making. The current approach to the analysis of clinical trials is to analyze efficacy and safety separately and then combine these analyses into a benefit:risk assessment. Many assume that this will effectively describe the impact on patients. But this approach is suboptimal for evaluating the totality of effects on patients. We discuss methods for benefit:risk assessment that have greater pragmatism than methods that separately analyze efficacy and safety. These include the concepts of within-patient analyses and composite benefit:risk endpoints with a goal of understanding how to analyze one patient before trying to figure out how to analyze many. We discuss the desirability of outcome ranking (DOOR) and introduce the partial credit strategy using an example in a clinical trial evaluating the effects of a new antibiotic. As part of the example we introduce a strategy to engage patients as a resource to inform benefit:risk analyses consistent with the goal of measuring and weighing outcomes that are most important from the patient's perspective. We describe a broad vision for the future of clinical trials consistent with increased pragmatism. Greater focus on using endpoints to analyze patients rather than patients to analyze endpoints particularly in late-phase/stage clinical trials is an important part of this vision.