29 research outputs found
The distinct category of healthcare associated bloodstream infections
<p>Abstract</p> <p>Background</p> <p>Bloodstream infections (BSI) have been traditionally classified as either community acquired (CA) or hospital acquired (HA) in origin. However, a third category of healthcare-associated (HCA) community onset disease has been increasingly recognized. The objective of this study was to compare and contrast characteristics of HCA-BSI with CA-BSI and HA-BSI.</p> <p>Methods</p> <p>All first episodes of BSI occurring among adults admitted to hospitals in a large health region in Canada during 2000-2007 were identified from regional databases. Cases were classified using a series of validated algorithms into one of HA-BSI, HCA-BSI, or CA-BSI and compared on a number of epidemiologic, microbiologic, and outcome characteristics.</p> <p>Results</p> <p>A total of 7,712 patients were included; 2,132 (28%) had HA-BSI, 2,492 (32%) HCA-BSI, and 3,088 (40%) had CA-BSI. Patients with CA-BSI were significantly younger and less likely to have co-morbid medical illnesses than patients with HCA-BSI or HA-BSI (p < 0.001). The proportion of cases in males was higher for HA-BSI (60%; p < 0.001 vs. others) as compared to HCA-BSI or CA-BSI (52% and 54%; p = 0.13). The proportion of cases that had a poly-microbial etiology was significantly lower for CA-BSI (5.5%; p < 0.001) compared to both HA and HCA (8.6 vs. 8.3%). The median length of stay following BSI diagnosis 15 days for HA, 9 days for HCA, and 8 days for CA (p < 0.001). Overall the most common species causing bloodstream infection were <it>Escherichia coli, Staphylococcus aureus</it>, and <it>Streptococcus pneumoniae</it>. The distribution and relative rank of importance of these species varied according to classification of acquisition. Twenty eight day all cause case-fatality rates were 26%, 19%, and 10% for HA-BSI, HCA-BSI, and CA-BSI, respectively (p < 0.001).</p> <p>Conclusion</p> <p>Healthcare-associated community onset infections are distinctly different from CA and HA infections based on a number of epidemiologic, microbiologic, and outcome characteristics. This study adds further support for the classification of community onset BSI into separate CA and HCA categories.</p
Development of machine learning models for the detection of surgical site infections following total hip and knee arthroplasty: a multicenter cohort study
Abstract
Background
Population based surveillance of surgical site infections (SSIs) requires precise case-finding strategies. We sought to develop and validate machine learning models to automate the process of complex (deep incisional/organ space) SSIs case detection.
Methods
This retrospective cohort study included adult patients (age ≥ 18 years) admitted to Calgary, Canada acute care hospitals who underwent primary total elective hip (THA) or knee (TKA) arthroplasty between Jan 1st, 2013 and Aug 31st, 2020. True SSI conditions were judged by the Alberta Health Services Infection Prevention and Control (IPC) program staff. Using the IPC cases as labels, we developed and validated nine XGBoost models to identify deep incisional SSIs, organ space SSIs and complex SSIs using administrative data, electronic medical records (EMR) free text data, and both. The performance of machine learning models was assessed by sensitivity, specificity, positive predictive value, negative predictive value, F1 score, the area under the receiver operating characteristic curve (ROC AUC) and the area under the precision–recall curve (PR AUC). In addition, a bootstrap 95% confidence interval (95% CI) was calculated.
Results
There were 22,059 unique patients with 27,360 hospital admissions resulting in 88,351 days of hospital stay. This included 16,561 (60.5%) TKA and 10,799 (39.5%) THA procedures. There were 235 ascertained SSIs. Of them, 77 (32.8%) were superficial incisional SSIs, 57 (24.3%) were deep incisional SSIs, and 101 (42.9%) were organ space SSIs. The incidence rates were 0.37 for superficial incisional SSIs, 0.21 for deep incisional SSIs, 0.37 for organ space and 0.58 for complex SSIs per 100 surgical procedures, respectively. The optimal XGBoost models using administrative data and text data combined achieved a ROC AUC of 0.906 (95% CI 0.835–0.978), PR AUC of 0.637 (95% CI 0.528–0.746), and F1 score of 0.79 (0.67–0.90).
Conclusions
Our findings suggest machine learning models derived from administrative data and EMR text data achieved high performance and can be used to automate the detection of complex SSIs.Highlights
The incidence rates of surgical site infections following total hip and knee arthroplasty were 0.5 and 0.52 per 100 surgical procedures.
The incidence of SSIs varied significantly between care facilities (ranging from 0.53 to 1.71 per 100 procedures).
The optimal machine learning model achieved a ROC AUC of 0.906 (95% CI 0.835–0.978), PR AUC of 0.637 (95% CI 0.528–0.746), and F1 score of 0.79 (0.67–0.90)
Lessons learned from the Alberta Border Testing Pilot Program
BackgroundDuring the Coronavirus disease (COVID-19) pandemic, countries implemented border control and quarantine measures to reduce transmission. The Alberta Border Testing Pilot Program (ABTPP) allowed international travellers entering Alberta to reduce their quarantine period following two negative COVID-19 tests. We evaluated participant experiences with the ABTPP and implementation.MethodWe used a parallel convergent mixed-methods design to explore participant experiences through electronic web-based questionnaires (n = 21,089; n = 13,839) and semi-structured telephone interviews (n = 30). We evaluated implementation through three staff focus groups (n = 11). We analysed questionnaires using descriptive statistics and analysed interviews using inductive and deductive thematic analysis. We deductively coded focus group data using the 2009 Consolidated Framework for Implementation Research (CFIR).ResultsQuestionnaires indicated minimal issues with registration forms (91.7%), symptom reports (95.5%), and COVID-19 testing (95.7%). Most respondents (95.1%) expressed willingness to participate in the ABTPP again. Interviews revealed three themes related to participant experience: program efficiency, clarity of information, and requisite effort. Focus groups identified key implementation facilitators including the single health information system, strong stakeholder partnerships, and good communication across partnerships. Barriers included program complexity, implementation timeline, and evolving external context.DiscussionParticipants reported high satisfaction with the ABTPP. Border testing programs should have high efficiency, require low effort, and use messaging that is clear and consistent. The effective implementation of border testing programs may be facilitated by strong leadership, adaptability, automated components, good communication, and simple technology. Learnings from participants and staff may help improve the implementation of border control programs for future pandemics or other emergencies.ConclusionsThe ABTTP was a novel border control measure during the COVID-19 pandemic. Our evaluation of both participant and staff experiences demonstrated high levels of traveller satisfaction and identified areas for improvement that can inform the development of future border control measures
The Cost-Effectiveness of a Prevention Strategy for Clostridioides difficile Infections in Alberta Health Services
The clinical and economic burden of hospital-acquired Clostridioides difficile infection (HA-CDI) is significant, however there is uncertainty in the cost-effectiveness of implementing probiotics for the primary prevention of HA-CDI among hospitalized patients prescribed antibiotics. In this thesis we examined the predictors of mortality and length of stay among this patient population in Alberta. We determined the attributable cost of HA-CDI and applied these estimates in a cost-effectiveness analysis of probiotics for the primary prevention of HA-CDI in Alberta from the perspective of a publicly-funded healthcare system. We conducted three studies: a population-based, retrospective cohort study using clinical surveillance, administrative and laboratory databases to determine the predictors of 30-day all-cause and attributable mortality and length of stay; a propensity score-matched study to compare patients with HA-CDI to patients without CDI to determine the attributable cost of HA-CDI in Alberta; and a cost-effectiveness analysis using decision analytic modelling to evaluate the costs and consequences related to probiotic use for the primary prevention of CDI. We found that the incidence and mortality rates of HA-CDI are declining, though the latter was not statistically significant. Advancing age was associated with all outcomes after adjusting for a number of baseline factors. Increased baseline white blood cell counts were associated with a lower risk of mortality. Hospital-acquired CDI total adjusted costs were 27% higher and length of stay was 13% higher than non-cases of CDI. Oral probiotics as a preventive strategy for CDI resulted in a lower risk of CDI and cost-savings. Previous studies on the burden of HA-CDI have been limited in their size and scope. Our first study was the largest population-based cohort study evaluating predictors of mortality; while our second study was the first to use propensity score-matching and a micro-costing approach for the estimation of costs associated with HA-CDI. We were the first to conduct an economic evaluation of probiotics for the primary prevention of CDI. This work will be presented to Alberta Health Services to support the evaluation of probiotics as a preventive strategy against CDI and whether to scale up probiotics to all provincial hospitals
The Validation of a Novel Surveillance System for Monitoring of Bloodstream Infections in the Calgary Health Region
Bibliography: p. 160-181Includes copies of ethics approval and copyright permission. Original copies with original Partial Copyright Licence
How externalities impact an evaluation of strategies to prevent antimicrobial resistance in health care organizations
Abstract 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
Economic evaluations and their use in infection prevention and control: a narrative review
Abstract Background The objective of this review is to provide a comprehensive overview of the different types of economic evaluations that can be utilized by Infection Prevention and Control practitioners with a particular focus on the use of the quality adjusted life year, and its associated challenges. We also highlight existing economic evaluations published within Infection Prevention and Control, research gaps and future directions. Design Narrative Review. Conclusions To date the majority of economic evaluations within Infection Prevention and Control are considered partial economic evaluations. Acknowledging the challenges, which include variable utilities within infection prevention and control, a lack of randomized controlled trials, and difficulty in modelling infectious diseases in general, future economic evaluation studies should strive to be consistent with published guidelines for economic evaluations. This includes the use of quality adjusted life years. Further research is required to estimate utility scores of relevance within Infection Prevention and Control
Additional file 1: of How externalities impact an evaluation of strategies to prevent antimicrobial resistance in health care organizations
Medline (OVID)/Embase Search Strategy. Table with detailed online database search strategy. (DOCX 13 kb
Clinical Features and Outcomes of Serotype 19A Invasive Pneumococcal Disease in Calgary, Alberta
BACKGROUND: Streptoccocus pneumoniae serotype 19A (ST19A) became an important cause of invasive pneumococcal disease (IPD) after the introduction of the conjugate vaccine.OBJECTIVE: To examine the severity and outcome of ST19A IPD compared with non-ST19A IPD.METHODS: The Calgary Area Streptococcus pneumoniae Epidemiology Research (CASPER) study collects clinical and laboratory data on all IPD cases in Calgary, Alberta. Analysis was performed on data from 2000 to 2010 comparing ST19A and non-ST19A IPD cases. Adjusted linear and logistic regression models were used to examine outcomes of duration of appropriate intravenous antibiotic therapy and intensive care unit admission, respectively.RESULTS: ST19A tended to cause disease in younger patients. ST19A isolates were more often multidrug resistant (19% versus 0.3%; Pud_less_than0.001). Adjusted logistic regression showed no difference in intensive care unit admission between ST19A and non-ST19A IPD cases (OR 1.4 [95% CI 0.8 to 2.7]). An adjusted linear regression model showed patients ud_less_than18 years of age with a diagnosis of bacteremia and no risk factors infected with ST19A were, on average, treated with antibiotics 1.4 times (95% CI 1.1 to 1.9) as long as patients with non-19A IPD and the same baseline characteristics.DISCUSSION: ST19A IPD was associated with an increase in average time on antibiotics. Although many of the infecting strains of ST19A were within the threshold for susceptibility, they may be sufficiently resilient to require a longer duration of antibiotic therapy or higher dose to clear the infection.CONCLUSIONS: ST19A is more common in younger individuals, is more antibiotic resistant and may require longer average treatment duration.Peer Reviewe