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Pleural effusion is a common problem in our country, and most of these patients need invasive tests as they can't be evaluated by blood tests alone. The simplest of them is diagnostic pleural aspiration, and diagnostic techniques such as medical thoracoscopy are being performed more frequently than ever before. However, most physicians in India treat pleural effusion empirically, leading to delays in diagnosis, misdiagnosis and complications from wrong treatments. This situation must change, and the adoption of evidence-based protocols is urgently needed. Furthermore, the spectrum of pleural disease in India is different from that in the West, and yet Western guidelines and algorithms are used by Indian physicians. Therefore, India-specific consensus guidelines are needed. To fulfil this need, the Indian Chest Society and the National College of Chest Physicians; the premier societies for pulmonary physicians came together to create this National guideline. This document aims to provide evidence based recommendations on basic principles, initial assessment, diagnostic modalities and management of pleural effusions.
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BACKGROUND: Data on mixed mould infection with COVID-19-associated pulmonary aspergillosis (CAPA) and COVID-19-associated pulmonary mucormycosis (CAPM) are sparse. OBJECTIVES: To ascertain the prevalence of co-existent CAPA in CAPM (mixed mould infection) and whether mixed mould infection is associated with early mortality (≤7 days of diagnosis). METHODS: We retrospectively analysed the data collected from 25 centres across India on COVID-19-associated mucormycosis. We included only CAPM and excluded subjects with disseminated or rhino-orbital mucormycosis. We defined co-existent CAPA if a respiratory specimen showed septate hyphae on smear, histopathology or culture grew Aspergillus spp. We also compare the demography, predisposing factors, severity of COVID-19, and management of CAPM patients with and without CAPA. Using a case-control design, we assess whether mixed mould infection (primary exposure) were associated with early mortality in CAPM. RESULTS: We included 105 patients with CAPM. The prevalence of mixed mould infection was 20% (21/105). Patients with mixed mould infection experienced early mortality (9/21 [42.9%] vs. 15/84 [17.9%]; p = 0.02) and poorer survival at 6 weeks (7/21 [33.3] vs. 46/77 [59.7%]; p = 0.03) than CAPM alone. On imaging, consolidation was more commonly encountered with mixed mould infections than CAPM. Co-existent CAPA (odds ratio [95% confidence interval], 19.1 [2.62-139.1]) was independently associated with early mortality in CAPM after adjusting for hypoxemia during COVID-19 and other factors. CONCLUSION: Coinfection of CAPA and CAPM was not uncommon in our CAPM patients and portends a worse prognosis. Prospective studies from different countries are required to know the impact of mixed mould infection.
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COVID-19 , Coinfección , Mucormicosis , Humanos , COVID-19/complicaciones , COVID-19/mortalidad , Mucormicosis/mortalidad , Mucormicosis/epidemiología , Mucormicosis/complicaciones , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Prevalencia , Coinfección/mortalidad , Coinfección/epidemiología , Coinfección/microbiología , India/epidemiología , Adulto , Aspergilosis Pulmonar/complicaciones , Aspergilosis Pulmonar/mortalidad , Aspergilosis Pulmonar/epidemiología , SARS-CoV-2 , Anciano , Estudios de Casos y Controles , Enfermedades Pulmonares Fúngicas/mortalidad , Enfermedades Pulmonares Fúngicas/complicaciones , Enfermedades Pulmonares Fúngicas/epidemiologíaRESUMEN
Importance: Pneumonia is the most common infection requiring hospitalization and is a major reason for overuse of extended-spectrum antibiotics. Despite low risk of multidrug-resistant organism (MDRO) infection, clinical uncertainty often drives initial antibiotic selection. Strategies to limit empiric antibiotic overuse for patients with pneumonia are needed. Objective: To evaluate whether computerized provider order entry (CPOE) prompts providing patient- and pathogen-specific MDRO infection risk estimates could reduce empiric extended-spectrum antibiotics for non-critically ill patients admitted with pneumonia. Design, Setting, and Participants: Cluster-randomized trial in 59 US community hospitals comparing the effect of a CPOE stewardship bundle (education, feedback, and real-time MDRO risk-based CPOE prompts; n = 29 hospitals) vs routine stewardship (n = 30 hospitals) on antibiotic selection during the first 3 hospital days (empiric period) in non-critically ill adults (≥18 years) hospitalized with pneumonia. There was an 18-month baseline period from April 1, 2017, to September 30, 2018, and a 15-month intervention period from April 1, 2019, to June 30, 2020. Intervention: CPOE prompts recommending standard-spectrum antibiotics in patients ordered to receive extended-spectrum antibiotics during the empiric period who have low estimated absolute risk (<10%) of MDRO pneumonia, coupled with feedback and education. Main Outcomes and Measures: The primary outcome was empiric (first 3 days of hospitalization) extended-spectrum antibiotic days of therapy. Secondary outcomes included empiric vancomycin and antipseudomonal days of therapy and safety outcomes included days to intensive care unit (ICU) transfer and hospital length of stay. Outcomes compared differences between baseline and intervention periods across strategies. Results: Among 59 hospitals with 96â¯451 (51â¯671 in the baseline period and 44â¯780 in the intervention period) adult patients admitted with pneumonia, the mean (SD) age of patients was 68.1 (17.0) years, 48.1% were men, and the median (IQR) Elixhauser comorbidity count was 4 (2-6). Compared with routine stewardship, the group using CPOE prompts had a 28.4% reduction in empiric extended-spectrum days of therapy (rate ratio, 0.72 [95% CI, 0.66-0.78]; P < .001). Safety outcomes of mean days to ICU transfer (6.5 vs 7.1 days) and hospital length of stay (6.8 vs 7.1 days) did not differ significantly between the routine and CPOE intervention groups. Conclusions and Relevance: Empiric extended-spectrum antibiotic use was significantly lower among adults admitted with pneumonia to non-ICU settings in hospitals using education, feedback, and CPOE prompts recommending standard-spectrum antibiotics for patients at low risk of MDRO infection, compared with routine stewardship practices. Hospital length of stay and days to ICU transfer were unchanged. Trial Registration: ClinicalTrials.gov Identifier: NCT03697070.
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Antibacterianos , Programas de Optimización del Uso de los Antimicrobianos , Neumonía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Hospitalización , Sistemas de Entrada de Órdenes Médicas , Neumonía/tratamiento farmacológico , Neumonía Bacteriana/tratamiento farmacológico , Estados Unidos , Anciano de 80 o más AñosRESUMEN
Importance: Urinary tract infection (UTI) is the second most common infection leading to hospitalization and is often associated with gram-negative multidrug-resistant organisms (MDROs). Clinicians overuse extended-spectrum antibiotics although most patients are at low risk for MDRO infection. Safe strategies to limit overuse of empiric antibiotics are needed. Objective: To evaluate whether computerized provider order entry (CPOE) prompts providing patient- and pathogen-specific MDRO risk estimates could reduce use of empiric extended-spectrum antibiotics for treatment of UTI. Design, Setting, and Participants: Cluster-randomized trial in 59 US community hospitals comparing the effect of a CPOE stewardship bundle (education, feedback, and real-time and risk-based CPOE prompts; 29 hospitals) vs routine stewardship (n = 30 hospitals) on antibiotic selection during the first 3 hospital days (empiric period) in noncritically ill adults (≥18 years) hospitalized with UTI with an 18-month baseline (April 1, 2017-September 30, 2018) and 15-month intervention period (April 1, 2019-June 30, 2020). Interventions: CPOE prompts recommending empiric standard-spectrum antibiotics in patients ordered to receive extended-spectrum antibiotics who have low estimated absolute risk (<10%) of MDRO UTI, coupled with feedback and education. Main Outcomes and Measures: The primary outcome was empiric (first 3 days of hospitalization) extended-spectrum antibiotic days of therapy. Secondary outcomes included empiric vancomycin and antipseudomonal days of therapy. Safety outcomes included days to intensive care unit (ICU) transfer and hospital length of stay. Outcomes were assessed using generalized linear mixed-effect models to assess differences between the baseline and intervention periods. Results: Among 127â¯403 adult patients (71â¯991 baseline and 55â¯412 intervention period) admitted with UTI in 59 hospitals, the mean (SD) age was 69.4 (17.9) years, 30.5% were male, and the median Elixhauser Comorbidity Index count was 4 (IQR, 2-5). Compared with routine stewardship, the group using CPOE prompts had a 17.4% (95% CI, 11.2%-23.2%) reduction in empiric extended-spectrum days of therapy (rate ratio, 0.83 [95% CI, 0.77-0.89]; P < .001). The safety outcomes of mean days to ICU transfer (6.6 vs 7.0 days) and hospital length of stay (6.3 vs 6.5 days) did not differ significantly between the routine and intervention groups, respectively. Conclusions and Relevance: Compared with routine stewardship, CPOE prompts providing real-time recommendations for standard-spectrum antibiotics for patients with low MDRO risk coupled with feedback and education significantly reduced empiric extended-spectrum antibiotic use among noncritically ill adults admitted with UTI without changing hospital length of stay or days to ICU transfers. Trial Registration: ClinicalTrials.gov Identifier: NCT03697096.
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Antibacterianos , Programas de Optimización del Uso de los Antimicrobianos , Sistemas de Entrada de Órdenes Médicas , Infecciones Urinarias , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Hospitales Comunitarios , Tiempo de Internación , Infecciones Urinarias/tratamiento farmacológico , Anciano de 80 o más AñosRESUMEN
Background: In 2014, the Centers for Disease Control and Prevention (CDC) released the Core Elements of Hospital Antibiotic Stewardship Programs (ASPs) and began monitoring uptake through the National Healthcare Safety Network (NHSN) Annual Hospital Survey. In 2019, CDC updated the Core Elements and in 2022 released the Priorities for Hospital Core Element Implementation. We describe Core Element uptake from 2014 to 2021, provide a snapshot of specific ASP practices in acute care hospitals in 2021, and describe how we plan to monitor stewardship moving forward. Methods: We used the NHSN Annual Hospital Survey to summarize facility demographics and ASP practices and to monitor uptake of Core Elements. Questions have been updated over time, so not all data could be compared across years. Results: Uptake of all 7 Core Elements increased from 41% in 2014 to 95% in 2021. Uptake of all 6 Priority Elements was 10% in 2021, though 46% of hospitals met 4 or 5 of the possible 6 elements. Antibiotic stewardship was specifically listed in a contract or job description for about 60% of program leaders. The percentage of physician-pharmacist co-led programs rose from 23% to 64%. Seventy-six percent of hospitals reported implementing audit with feedback interventions. Conclusions: With nearly all acute care hospitals reporting uptake of the 7 Core Elements in 2021, and with more evidence for which ASP practices are most effective, the Priorities for Hospital Core Element Implementation were released in 2022 to help enhance the quality and impact of existing ASPs.
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From December 2020 through March 2023, the COVID-19 vaccination efforts in long-term care (LTC) settings, identified many gaps and opportunities to improve public health capacity to support vaccine distribution, education, and documentation of COVID-19 vaccines administered to LTC residents and staff. Partner engagement at the local, state, and federal levels helped establish pathways for dissemination of information, improve access and delivery of vaccines, and expand reporting of vaccine administration data to monitor the impact of COVID-19 vaccination in LTC settings. Sustaining the improvements to the vaccine infrastructure in LTC settings that were created or enhanced during the COVID-19 vaccination efforts is critical for the protection of residents and staff against COVID-19 and other vaccine preventable respiratory outbreaks in the future.
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Antimicrobial use data reported to the National Healthcare Safety Network's Antimicrobial Use and Resistance Module between January 2019 and July 2022 were analyzed to assess the impact of the COVID-19 pandemic on inpatient antimicrobial use.
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Antiinfecciosos , COVID-19 , Estados Unidos/epidemiología , Humanos , Antibacterianos/uso terapéutico , Pacientes Internos , PandemiasRESUMEN
Antimicrobial resistance remains a significant global public health threat. Although development of novel antibiotics can be challenging, several new antibiotics with improved activity against multidrug-resistant Gram-negative organisms have recently been commercialised. Expanding access to these antibiotics is a global public health priority that should be coupled with improving access to quality diagnostics, health care with adequately trained professionals, and functional antimicrobial stewardship programmes. This comprehensive approach is essential to ensure responsible use of these new antibiotics.
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Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias Gramnegativas , Instituciones de SaludRESUMEN
OBJECTIVES: To compare COVID-19-associated pulmonary mucormycosis (CAPM) with COVID-19-associated rhino-orbital mucormycosis (CAROM), ascertain factors associated with CAPM among patients with COVID-19, and identify factors associated with 12-week mortality in CAPM. METHODS: We performed a retrospective multicentre cohort study. All study participants had COVID-19. We enrolled CAPM, CAROM, and COVID-19 subjects without mucormycosis (controls; age-matched). We collected information on demography, predisposing factors, and details of COVID-19 illness. Univariable analysis was used to compare CAPM and CAROM. We used multivariable logistic regression to evaluate factors associated with CAPM (with hypoxemia during COVID-19 as the primary exposure) and at 12-week mortality. RESULTS: We included 1724 cases (CAPM [n = 122], CAROM [n = 1602]) and 3911 controls. Male sex, renal transplantation, multimorbidity, neutrophil-lymphocyte ratio, intensive care admission, and cumulative glucocorticoid dose for COVID-19 were significantly higher in CAPM than in CAROM. On multivariable analysis, COVID-19-related hypoxemia (aOR, 2.384; 95% CI, 1.209-4.700), male sex, rural residence, diabetes mellitus, serum C-reactive protein, glucocorticoid, and zinc use during COVID-19 were independently associated with CAPM. CAPM reported a higher 12-week mortality than CAROM (56 of the 107 [52.3%] vs. 413 of the 1356 [30.5%]; p = 0.0001). Hypoxemia during COVID-19 (aOR [95% CI], 3.70 [1.34-10.25]) and Aspergillus co-infection (aOR [95% CI], 5.40 [1.23-23.64]) were independently associated with mortality in CAPM, whereas surgery was associated with better survival. DISCUSSION: CAPM is a distinct entity with a higher mortality than CAROM. Hypoxemia during COVID-19 illness is associated with CAPM. COVID-19 hypoxemia and Aspergillus co-infection were associated with higher mortality in CAPM.
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Aspergilosis , COVID-19 , Coinfección , Mucormicosis , Humanos , Masculino , Mucormicosis/complicaciones , Mucormicosis/epidemiología , Estudios Retrospectivos , Estudios de Cohortes , Glucocorticoides , COVID-19/complicaciones , COVID-19/terapia , Factores de Riesgo , India/epidemiología , Hipoxia/complicacionesRESUMEN
Nursing home residents are at risk for becoming infected with and experiencing severe complications from respiratory viruses, including SARS-CoV-2, influenza, and respiratory syncytial virus (RSV). Fall 2023 is the first season during which vaccines are simultaneously available to protect older adults in the United States against all three of these respiratory viruses. Nursing homes are required to report COVID-19 vaccination coverage and can voluntarily report influenza and RSV vaccination coverage among residents to CDC's National Healthcare Safety Network. The purpose of this study was to assess COVID-19, influenza, and RSV vaccination coverage among nursing home residents during the current 2023-24 respiratory virus season. As of December 10, 2023, 33.1% of nursing home residents were up to date with vaccination against COVID-19. Among residents at 20.2% and 19.4% of facilities that elected to report, coverage with influenza and RSV vaccines was 72.0% and 9.8%, respectively. Vaccination varied by U.S. Department of Health and Human Services region, social vulnerability index level, and facility size. There is an urgent need to protect nursing home residents against severe outcomes of respiratory illnesses by continuing efforts to increase vaccination against COVID-19 and influenza and discussing vaccination against RSV with eligible residents during the ongoing 2023-24 respiratory virus season.
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COVID-19 , Vacunas contra la Influenza , Gripe Humana , Virus Sincitial Respiratorio Humano , Humanos , Estados Unidos/epidemiología , Anciano , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Vacunas contra la COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Casas de Salud , Vacunación , Atención a la SaludRESUMEN
Through the Centers for Medicare and Medicaid Services Promoting Interoperability Program, more hospitals will be reporting to the National Healthcare Safety Network Antimicrobial Use (AU) Option. We highlight the next steps and opportunities for measurement of AU to optimize prescribing.
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Sepsis, life-threatening organ dysfunction secondary to infection, contributes to at least 1.7 million adult hospitalizations and at least 350,000 deaths annually in the United States. Sepsis care is complex, requiring the coordination of multiple hospital departments and disciplines. Sepsis programs can coordinate these efforts to optimize patient outcomes. The 2022 National Healthcare Safety Network (NHSN) annual survey evaluated the prevalence and characteristics of sepsis programs in acute care hospitals. Among 5,221 hospitals, 3,787 (73%) reported having a committee that monitors and reviews sepsis care. Prevalence of these committees varied by hospital size, ranging from 53% among hospitals with 0-25 beds to 95% among hospitals with >500 beds. Fifty-five percent of all hospitals provided dedicated time (including assigned protected time or job description requirements) for leaders of these committees to manage a program and conduct daily activities, and 55% of committees reported involvement with antibiotic stewardship programs. These data highlight opportunities, particularly in smaller hospitals, to improve the care and outcomes of patients with sepsis in the United States by ensuring that all hospitals have sepsis programs with protected time for program leaders, engagement of medical specialists, and integration with antimicrobial stewardship programs. CDC's Hospital Sepsis Program Core Elements provides a guide to assist hospitals in developing and implementing effective sepsis programs that complement and facilitate the implementation of existing clinical guidelines and improve patient care. Future NHSN annual surveys will monitor uptake of these sepsis core elements.
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Instituciones de Salud , Sepsis , Estados Unidos/epidemiología , Adulto , Humanos , Hospitales , Sepsis/epidemiología , Sepsis/terapia , Centers for Disease Control and Prevention, U.S. , Atención a la SaludRESUMEN
Antibiotic stewardship has seen transformative change over the past decade. Antibiotic stewardship infrastructure has grown significantly across the spectrum of health care in hospitals, nursing homes, and ambulatory settings, and issues related to improving antibiotic use have become central to high-level policy discussions, regulations, and legislation. Herein we review important events and developments in stewardship across the spectrum of care with a focus on (1) infrastructure and implementation, (2) requirement and regulation, and (3) measurement of antibiotic use and other outcomes.
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INTRODUCTION: Racial and ethnic minorities are disproportionately affected by end-stage kidney disease (ESKD). ESKD patients on dialysis are at increased risk for Staphylococcus aureus bloodstream infections, but racial, ethnic, and socioeconomic disparities associated with this outcome are not well described. METHODS: Surveillance data from the 2020 National Healthcare Safety Network (NHSN) and the 2017-2020 Emerging Infections Program (EIP) were used to describe bloodstream infections among patients on hemodialysis (hemodialysis patients) and were linked to population-based data sources (CDC/Agency for Toxic Substances and Disease Registry [ATSDR] Social Vulnerability Index [SVI], United States Renal Data System [USRDS], and U.S. Census Bureau) to examine associations with race, ethnicity, and social determinants of health. RESULTS: In 2020, 4,840 dialysis facilities reported 14,822 bloodstream infections to NHSN; 34.2% were attributable to S. aureus . Among seven EIP sites, the S. aureus bloodstream infection rate during 2017-2020 was 100 times higher among hemodialysis patients (4,248 of 100,000 person-years) than among adults not on hemodialysis (42 of 100,000 person-years). Unadjusted S. aureus bloodstream infection rates were highest among non-Hispanic Black or African American (Black) and Hispanic or Latino (Hispanic) hemodialysis patients. Vascular access via central venous catheter was strongly associated with S. aureus bloodstream infections (NHSN: adjusted rate ratio [aRR] = 6.2; 95% CI = 5.7-6.7 versus fistula; EIP: aRR = 4.3; 95% CI = 3.9-4.8 versus fistula or graft). Adjusting for EIP site of residence, sex, and vascular access type, S. aureus bloodstream infection risk in EIP was highest in Hispanic patients (aRR = 1.4; 95% CI = 1.2-1.7 versus non-Hispanic White [White] patients), and patients aged 18-49 years (aRR = 1.7; 95% CI = 1.5-1.9 versus patients aged ≥65 years). Areas with higher poverty levels, crowding, and lower education levels accounted for disproportionately higher proportions of hemodialysis-associated S. aureus bloodstream infections. CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Disparities exist in hemodialysis-associated S. aureus infections. Health care providers and public health professionals should prioritize prevention and optimized treatment of ESKD, identify and address barriers to lower-risk vascular access placement, and implement established best practices to prevent bloodstream infections.
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Fallo Renal Crónico , Sepsis , Adulto , Humanos , Estados Unidos/epidemiología , Staphylococcus aureus , Diálisis Renal/efectos adversos , Etnicidad , Fallo Renal Crónico/terapia , Fallo Renal Crónico/etiología , Sepsis/etiología , Signos Vitales , Disparidades en Atención de SaludRESUMEN
Introduction: Racial and ethnic minorities are disproportionately affected by end-stage kidney disease (ESKD). ESKD patients on dialysis are at increased risk for Staphylococcus aureus bloodstream infections, but racial, ethnic, and socioeconomic disparities associated with this outcome are not well described. Methods: Surveillance data from the 2020 National Healthcare Safety Network (NHSN) and the 2017-2020 Emerging Infections Program (EIP) were used to describe bloodstream infections among patients on hemodialysis (hemodialysis patients) and were linked to population-based data sources (CDC/Agency for Toxic Substances and Disease Registry [ATSDR] Social Vulnerability Index [SVI], United States Renal Data System [USRDS], and U.S. Census Bureau) to examine associations with race, ethnicity, and social determinants of health. Results: In 2020, 4,840 dialysis facilities reported 14,822 bloodstream infections to NHSN; 34.2% were attributable to S. aureus. Among seven EIP sites, the S. aureus bloodstream infection rate during 2017-2020 was 100 times higher among hemodialysis patients (4,248 of 100,000 person-years) than among adults not on hemodialysis (42 of 100,000 person-years). Unadjusted S. aureus bloodstream infection rates were highest among non-Hispanic Black or African American (Black) and Hispanic or Latino (Hispanic) hemodialysis patients. Vascular access via central venous catheter was strongly associated with S. aureus bloodstream infections (NHSN: adjusted rate ratio [aRR] = 6.2; 95% CI = 5.7-6.7 versus fistula; EIP: aRR = 4.3; 95% CI = 3.9-4.8 versus fistula or graft). Adjusting for EIP site of residence, sex, and vascular access type, S. aureus bloodstream infection risk in EIP was highest in Hispanic patients (aRR = 1.4; 95% CI = 1.2-1.7 versus non-Hispanic White [White] patients), and patients aged 18-49 years (aRR = 1.7; 95% CI = 1.5-1.9 versus patients aged ≥65 years). Areas with higher poverty levels, crowding, and lower education levels accounted for disproportionately higher proportions of hemodialysis-associated S. aureus bloodstream infections. Conclusions and implications for public health practice: Disparities exist in hemodialysis-associated S. aureus infections. Health care providers and public health professionals should prioritize prevention and optimized treatment of ESKD, identify and address barriers to lower-risk vascular access placement, and implement established best practices to prevent bloodstream infections.
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Fallo Renal Crónico , Sepsis , Infecciones Estafilocócicas , Adulto , Humanos , Estados Unidos/epidemiología , Diálisis Renal/efectos adversos , Staphylococcus aureus , Etnicidad , Infecciones Estafilocócicas/epidemiología , Fallo Renal Crónico/epidemiología , Fallo Renal Crónico/terapia , Fallo Renal Crónico/etiología , Sepsis/etiología , Signos Vitales , Disparidades en Atención de SaludRESUMEN
The language for expressing comparisons is often complex and nuanced, making supporting natural language-based visual comparison a non-trivial task. To better understand how people reason about comparisons in natural language, we explore a design space of utterances for comparing data entities. We identified different parameters of comparison utterances that indicate what is being compared (i.e., data variables and attributes) as well as how these parameters are specified (i.e., explicitly or implicitly). We conducted a user study with sixteen data visualization experts and non-experts to investigate how they designed visualizations for comparisons in our design space. Based on the rich set of visualization techniques observed, we extracted key design features from the visualizations and synthesized them into a subset of sixteen representative visualization designs. We then conducted a follow-up study to validate user preferences for the sixteen representative visualizations corresponding to utterances in our design space. Findings from these studies suggest guidelines and future directions for designing natural language interfaces and recommendation tools to better support natural language comparisons in visual analytics.