Hospital-Acquired Methicillin-Resistant Staphylococcus aureus Bloodstream Infections in Québec: Impact of Guidelines

The Prevalence, Risk, and Management of Methicillin-Resistant Staphylococcus aureus Infection in Diverse Populations across Canada: A Systematic Review

Methicillin-resistant Staphylococcus aureus (MRSA) first emerged after methicillin was introduced to combat penicillin resistance, and its prevalence in Canada has increased since the first MRSA outbreak in the early 1980s. We reviewed the existing literature on MRSA prevalence in Canada over time and in diverse populations across the country. MRSA prevalence increased steadily in the 1990s and 2000s and remains a public health concern in Canada, especially among vulnerable populations, such as rural, remote, and Indigenous communities. Antibiotic resistance patterns and risk factors for MRSA infection were also reported. All studies reported high susceptibility (>85%) to trimethoprim-sulfamethoxazole, with no significant resistance reported for vancomycin, linezolid, or rifampin. While MRSA continues to have susceptibility to several antibiotics, the high and sometimes variable resistance rates to other drugs underscores the importance of antimicrobial stewardship. Risk factors for high MRSA infection rates related to infection control measures, low socioeconomic status, and personal demographic characteristics were also reported. Additional surveillance, infection control measures, enhanced anti-microbial stewardship, and community education programs are necessary to decrease MRSA prevalence and minimize the public health risk posed by this pathogen.

Use of interrupted time series methods in the evaluation of health system quality improvement interventions: a methodological systematic review

BACKGROUND

When randomisation is not possible, interrupted time series (ITS) design has increasingly been advocated as a more robust design to evaluating health system quality improvement (QI) interventions given its ability to control for common biases in healthcare QI. However, there is a potential risk of producing misleading results when this rather robust design is not used appropriately. We performed a methodological systematic review of the literature to investigate the extent to which the use of ITS has followed best practice standards and recommendations in the evaluation of QI interventions.

METHODS

We searched multiple databases from inception to June 2018 to identify QI intervention studies that were evaluated using ITS. There was no restriction on date, language and participants. Data were synthesised narratively using appropriate descriptive statistics. The risk of bias for ITS studies was assessed using the Cochrane Effective Practice and Organisation of Care standard criteria. The systematic review protocol was registered in PROSPERO (registration number: CRD42018094427).

RESULTS

Of 4061 potential studies and 2028 unique records screened for inclusion, 120 eligible studies assessed eight QI strategies and were from 25 countries. Most studies were published since 2010 (86.7%), reported data using monthly interval (71.4%), used ITS without a control (81%) and modelled data using segmented regression (62.5%). Autocorrelation was considered in 55% of studies, seasonality in 20.8% and non-stationarity in 8.3%. Only 49.2% of studies specified the ITS impact model. The risk of bias was high or very high in 72.5% of included studies and did not change significantly over time.

CONCLUSIONS

The use of ITS in the evaluation of health system QI interventions has increased considerably over the past decade. However, variations in methodological considerations and reporting of ITS in QI remain a concern, warranting a need to develop and reinforce formal reporting guidelines to improve its application in the evaluation of health system QI interventions.

Printed educational materials: effects on professional practice and healthcare outcomes

BACKGROUND

Printed educational materials are widely used dissemination strategies to improve the quality of healthcare professionals' practice and patient health outcomes. Traditionally they are presented in paper formats such as monographs, publication in peer-reviewed journals and clinical guidelines. This is the fourth update of the review.

OBJECTIVES

To assess the effect of printed educational materials (PEMs) on the practice of healthcare professionals and patient health outcomes. To explore the influence of some of the characteristics of the printed educational materials (e.g. source, content, format) on their effect on healthcare professionals' practice and patient health outcomes.

SEARCH METHODS

We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), HealthStar, CINAHL, ERIC, CAB Abstracts, Global Health, and EPOC Register from their inception to 6 February 2019. We checked the reference lists of all included studies and relevant systematic reviews.

SELECTION CRITERIA

We included randomised trials (RTs), controlled before-after studies (CBAs) and interrupted time series studies (ITSs) that evaluated the impact of PEMs on healthcare professionals' practice or patient health outcomes. We included three types of comparisons: (1) PEM versus no intervention, (2) PEM versus single intervention, (3) multifaceted intervention where PEM is included versus multifaceted intervention without PEM. Any objective measure of professional practice (e.g. prescriptions for a particular drug), or patient health outcomes (e.g. blood pressure) were included.

DATA COLLECTION AND ANALYSIS

Two reviewers undertook data extraction independently. Disagreements were resolved by discussion. For analyses, we grouped the included studies according to study design, type of outcome and type of comparison. For controlled trials, we reported the median effect size for each outcome within each study, the median effect size across outcomes for each study and the median of these effect sizes across studies. Where data were available, we re-analysed the ITS studies by converting all data to a monthly basis and estimating the effect size from the change in the slope of the regression line between before and after implementation of the PEM. We reported median changes in slope for each outcome, for each study, and then across studies. We standardised all changes in slopes by their standard error, allowing comparisons and combination of different outcomes. We categorised each PEM according to potential effects modifiers related to the source of the PEMs, the channel used for their delivery, their content, and their format. We assessed the risks of bias of all the included studies.

MAIN RESULTS

We included 84 studies: 32 RTs, two CBAs and 50 ITS studies. Of the 32 RTs, 19 were cluster RTs that used various units of randomisation, such as practices, health centres, towns, or areas. The majority of the included studies (82/84) compared the effectiveness of PEMs to no intervention. Based on the RTs that provided moderate-certainty evidence, we found that PEMs distributed to healthcare professionals probably improve their practice, as measured with dichotomous variables, compared to no intervention (median absolute risk difference (ARD): 0.04; interquartile range (IQR): 0.01 to 0.09; 3,963 healthcare professionals randomised within 3073 units). We could not confirm this finding using the evidence gathered from continuous variables (standardised mean difference (SMD): 0.11; IQR: -0.16 to 0.52; 1631 healthcare professionals randomised within 1373 units ), from the ITS studies (standardised median change in slope = 0.69; 35 studies), or from the CBA study because the certainty of this evidence was very low. We also found, based on RTs that provided moderate-certainty evidence, that PEMs distributed to healthcare professionals probably make little or no difference to patient health as measured using dichotomous variables, compared to no intervention (ARD: 0.02; IQR: -0.005 to 0.09; 935,015 patients randomised within 959 units). The evidence gathered from continuous variables (SMD: 0.05; IQR: -0.12 to 0.09; 6,737 patients randomised within 594 units) or from ITS study results (standardised median change in slope = 1.12; 8 studies) do not strengthen these findings because the certainty of this evidence was very low. Two studies (a randomised trial and a CBA) compared a paper-based version to a computerised version of the same PEM. From the RT that provided evidence of low certainty, we found that PEM in computerised versions may make little or no difference to professionals' practice compared to PEM in printed versions (ARD: -0.02; IQR: -0.03 to 0.00; 139 healthcare professionals randomised individually). This finding was not strengthened by the CBA study that provided very low certainty evidence (SMD: 0.44; 32 healthcare professionals). The data gathered did not allow us to conclude which PEM characteristics influenced their effectiveness. The methodological quality of the included studies was variable. Half of the included RTs were at risk of selection bias. Most of the ITS studies were conducted retrospectively, without prespecifying the expected effect of the intervention, or acknowledging the presence of a secular trend.

AUTHORS' CONCLUSIONS

The results of this review suggest that, when used alone and compared to no intervention, PEMs may slightly improve healthcare professionals' practice outcomes and patient health outcomes. The effectiveness of PEMs compared to other interventions, or of PEMs as part of a multifaceted intervention, is uncertain.

Pathogens causing central-line-associated bloodstream infections in acute-care hospitals-United States, 2011-2017

OBJECTIVE

To describe pathogen distribution and rates for central-line-associated bloodstream infections (CLABSIs) from different acute-care locations during 2011-2017 to inform prevention efforts.

METHODS

CLABSI data from the Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) were analyzed. Percentages and pooled mean incidence density rates were calculated for a variety of pathogens and stratified by acute-care location groups (adult intensive care units [ICUs], pediatric ICUs [PICUs], adult wards, pediatric wards, and oncology wards).

RESULTS

From 2011 to 2017, 136,264 CLABSIs were reported to the NHSN by adult and pediatric acute-care locations; adult ICUs and wards reported the most CLABSIs: 59,461 (44%) and 40,763 (30%), respectively. In 2017, the most common pathogens were Candida spp/yeast in adult ICUs (27%) and Enterobacteriaceae in adult wards, pediatric wards, oncology wards, and PICUs (23%-31%). Most pathogen-specific CLABSI rates decreased over time, excepting Candida spp/yeast in adult ICUs and Enterobacteriaceae in oncology wards, which increased, and Staphylococcus aureus rates in pediatric locations, which did not change.

CONCLUSIONS

The pathogens associated with CLABSIs differ across acute-care location groups. Learning how pathogen-targeted prevention efforts could augment current prevention strategies, such as strategies aimed at preventing Candida spp/yeast and Enterobacteriaceae CLABSIs, might further reduce national rates.

The challenge of converting Gram-positive-only compounds into broad-spectrum antibiotics

Multidrug resistant Gram-negative bacterial infections are on the rise, and there is a lack of new classes of drugs to treat these pathogens. This drug shortage is largely due to the challenge of finding antibiotics that can permeate and persist inside Gram-negative species. Efforts to understand the molecular properties that enable certain compounds to accumulate in Gram-negative bacteria based on retrospective studies of known antibiotics have not been generally actionable in the development of new antibiotics. A recent assessment of the ability of >180 diverse small molecules to accumulate in Escherichia coli led to predictive guidelines for compound accumulation in E. coli. These "eNTRy rules" state that compounds are most likely to accumulate if they contain a nonsterically encumbered ionizable Nitrogen (primary amines are the best), have low Three-dimensionality (globularity ≤ 0.25), and are relatively Rigid (rotatable bonds ≤ 5). In this review, we look back through 50+ years of antibacterial research and 1000s of derivatives and assess this historical data set through the lens of these predictive guidelines. The results are consistent with the eNTRy rules, suggesting that the eNTRy rules may provide an actionable and general roadmap for the conversion of Gram-positive-only compounds into broad-spectrum antibiotics.