Safety and tolerability of a low glycemic load dietary intervention in adults with cystic fibrosis: a pilot study.

Introduction: To achieve and maintain adequate weight, people with cystic fibrosis (CF) May often consume energy-dense, nutrient-poor foods high in added sugars and refined carbohydrates; however, little is known about the glycemic and metabolic effects of dietary composition in this patient population. The objective of this pilot study was to investigate the safety and tolerability of a low glycemic load (LGL) diet in adults with CF and abnormal glucose tolerance (AGT). Methods: Ten adults with CF and AGT completed this prospective, open-label pilot study. Mean age was 27.0 ± 2.1 years, 64% were female, and all had pancreatic insufficiency. Each participant followed his/her typical diet for 2 weeks, then transitioned to a LGL diet via meal delivery service for 8 weeks. The primary outcome was change in weight from baseline to study completion, with safety established if no significant decline was noted. Other key safety outcomes included change in hypoglycemia measured by patient report and continuous glucose monitoring (CGM). Exploratory outcomes included changes in other CGM measures, body composition by dual energy X-ray absorptiometry (DXA), and patient reported outcomes. Results: There were no significant changes in weight or in subjectively-reported or objectively-measured hypoglycemia. Favorable non-significant changes were noted in CGM measures of hyperglycemia and glycemic variability, DXA measures of fat mass, and gastrointestinal symptom surveys. Discussion: A LGL dietary intervention was safe and well tolerated in adults with CF and AGT. These results lay the groundwork for future trials investigating the impact of low-glycemic dietary interventions on metabolic outcomes in the CF population.

Using multi-level regression to determine associations and estimate causes and effects in clinical anesthesia due to patient, practitioner and hospital or health system practice variability.

In this research methods tutorial of clinical anesthesia, we will explore techniques to estimate the influence of a myriad of factors on patient outcomes. Big data that contain information on patients, treated by individual anesthesiologists and surgical teams, at different hospitals, have an inherent multi-level data structure (Fig. 1). While researchers often attempt to determine the association between patient factors and outcomes, that does not provide clinicians with the whole story. Patient care is clustered together according to clinicians and hospitals where they receive treatment. Therefore, multi-level regression models are needed to validly estimate the influence of each factor at each level. In addition, we will explore how to estimate the influence that variability-for example, one anesthesiologist deciding to do one thing, while another takes a different approach-has on outcomes for patients, using the intra-class correlation coefficient for continuous outcomes and the median odds ratio for binary outcomes. From this tutorial, you should acquire a clearer understanding of how to perform and interpret multi-level regression modeling and estimate the influence of variable clinical practices on patient outcomes in order to answer common but complex clinical questions. Fig. 1 Infographics.

Trends in characteristics, interventions, and outcomes of hospitalized patients with COVID-19 in Canada: a multicentre prospective cohort study.

PURPOSE: Our objective was to investigate the temporal trends in baseline characteristics, interventions, and clinical outcomes in patients hospitalized with COVID-19 in Canada over five pandemic waves. METHODS: We conducted a multicentre prospective cohort study enrolling adults and children admitted with COVID-19 from 47 Canadian hospitals. We compared characteristics, interventions, and outcomes of patients across five distinct pandemic waves. RESULTS: We enrolled 5,285 patients between 2 January 2020 and 8 February 2022. The mean (standard deviation) age was 62.6 (21.0) yr; 41.2% (n = 2,176) were female, and 48% (n = 2,539) required admission to an intensive care unit (ICU), of whom 60.3% (n = 1,530) underwent invasive mechanical ventilation. The proportion of vaccinated patients increased over time. The proportion of vaccinated hospitalized patients progressing to require ICU admission fell over pandemic waves while the proportion of unvaccinated hospitalized patients progressing to require ICU admission did not. Patients were most commonly treated with corticosteroids (48.7%; n = 2,575); use of corticosteroids and other evidence-based treatments increased over time. Hospital mortality was 22.1% (n = 1,166) among all patients, 30.2% (n = 766) among those admitted to an ICU, and 37.9% (n = 580) among those requiring invasive mechanical ventilation. Younger age, absence of chronic cardiac or pulmonary disease, severity of illness at admission, and prior vaccination was associated with a lower mortality; however, pandemic wave itself was not. CONCLUSION: Among patients hospitalized in Canada with COVID-19, several clinical factors including prior vaccination were associated with lower mortality, but pandemic wave was not.

RéSUMé: OBJECTIF: Notre objectif était d'étudier les tendances temporelles des caractéristiques de base, des interventions et des issues cliniques chez la patientèle hospitalisée pour cause de COVID-19 au Canada au cours de cinq vagues de la pandémie. MéTHODE: Nous avons mené une étude de cohorte prospective multicentrique auprès d'adultes et d'enfants admis·es avec la COVID-19 dans 47 hôpitaux canadiens. Nous avons comparé les caractéristiques, les interventions et les issues des patient·es sur cinq vagues pandémiques distinctes. RéSULTATS: Nous avons recruté 5285 patient·es entre le 2 janvier 2020 et le 8 février 2022. L'âge moyen (écart type) était de 62,6 (21,0) ans; 41,2 % (n = 2176) étaient des femmes, et 48 % (n = 2539) ont dû être admis·es à une unité de soins intensifs (USI), dont 60,3 % (n = 1530) ont bénéficié de ventilation mécanique invasive. La proportion de patient·es vacciné·es a augmenté au fil du temps. La proportion de patient·es hospitalisé·es vacciné·es nécessitant une admission aux soins intensifs a diminué au cours des vagues pandémiques, tandis que la proportion de patient·es hospitalisé·es non vacciné·es nécessitant une admission aux soins intensifs n'a pas diminué. Les patient·es étaient le plus souvent traité·es par corticostéroïdes (48,7 %; n = 2575); l'utilisation de corticostéroïdes et d'autres traitements fondés sur des données probantes a augmenté au fil du temps. La mortalité hospitalière était de 22,1 % (n = 1166) parmi l'ensemble des patient·es, 30,2 % (n = 766) chez les personnes admises à l'unité de soins intensifs, et 37,9 % (n = 580) parmi les personnes nécessitant une ventilation mécanique invasive. Le jeune âge, l'absence de maladie cardiaque ou pulmonaire chronique, la gravité de la maladie à l'admission et la vaccination antérieure étaient associés à une mortalité plus faible; cependant, la vague pandémique elle-même ne l'était pas. CONCLUSION: Parmi les personnes hospitalisées au Canada en raison de la COVID-19, plusieurs facteurs cliniques, y compris la vaccination antérieure, étaient associés à une mortalité plus faible, mais pas la vague pandémique.

Effects of Losartan on Patients Hospitalized for Acute COVID-19: A Randomized Controlled Trial.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) down-regulates angiotensin-converting enzyme 2, potentially increasing angiotensin II. We hypothesized that losartan compared to usual care decreases mortality and is safe in patients hospitalized with coronavirus disease 2019 (COVID-19). We aimed to evaluate the effect of losartan versus usual care on 28-day mortality in patients hospitalized for acute COVID-19. METHODS: Eligibility criteria included adults admitted for acute COVID-19. Exclusion criteria were hypotension, hyperkalemia, acute kidney injury, and use of angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors within 7 days. Participants were randomized to losartan 25-100 mg/day orally for the hospital duration or 3 months or the control arm (usual care) in 29 hospitals in Canada and France. The primary outcome was 28-day mortality. Secondary outcomes were hospital mortality, organ support, and serious adverse events (SAEs). RESULTS: The trial was stopped early because of a serious safety concern with losartan. In 341 patients, any SAE and hypotension were significantly higher in the losartan versus usual care groups (any SAE: 39.8% vs 27.2%, respectively, P = .01; hypotension: 30.4% vs 15.3%, respectively, P < .001) in both ward and intensive care patients. The 28-day mortality did not differ between losartan (6.5%) versus usual care (5.9%) (odds ratio, 1.11 [95% confidence interval, .47-2.64]; P = .81), nor did organ dysfunction or secondary outcomes. CONCLUSIONS: Caution is needed in deciding which patients to start or continue using ARBs in patients hospitalized with pneumonia to mitigate risk of hypotension, acute kidney injury, and other side effects. ARBs should not be added to care of patients hospitalized for acute COVID-19. CLINICAL TRIALS REGISTRATION: NCT04606563.

What Is the Potential Value of a Randomized Trial of Different Thresholds to Initiate Invasive Ventilation? A Health Economic Analysis.

OBJECTIVES: To estimate the expected value of undertaking a future randomized controlled trial of thresholds used to initiate invasive ventilation compared with usual care in hypoxemic respiratory failure. PERSPECTIVE: Publicly funded healthcare payer. SETTING: Critical care units capable of providing invasive ventilation and unconstrained by resource limitations during usual (nonpandemic) practice. METHODS: We performed a model-based cost-utility estimation with individual-level simulation and value-of-information analysis focused on adults, admitted to critical care, receiving noninvasive oxygen. In the primary scenario, we compared hypothetical threshold A to usual care, where threshold A resulted in increased use of invasive ventilation and improved survival compared with usual care. In the secondary scenario, we compared hypothetical threshold B to usual care, where threshold B resulted in decreased use of invasive ventilation and similar survival compared with usual care. We assumed a willingness-to-pay of 100,000 Canadian dollars (CADs) per quality-adjusted life year. RESULTS: In the primary scenario, threshold A was cost-effective compared with usual care due to improved hospital survival (78.1% vs. 75.1%), despite more use of invasive ventilation (62% vs. 30%) and higher lifetime costs (86,900 vs. 75,500 CAD). In the secondary scenario, threshold B was cost-effective compared with usual care due to similar survival (74.5% vs. 74.6%) with less use of invasive ventilation (20.2% vs. 27.6%) and lower lifetime costs (71,700 vs. 74,700 CAD). Value-of-information analysis showed that the expected value to Canadian society over 10 years of a 400-person randomized trial comparing a threshold for invasive ventilation to usual care in hypoxemic respiratory failure was 1.35 billion CAD or more in both scenarios. CONCLUSIONS: It would be highly valuable to society to identify thresholds that, in comparison to usual care, either increase survival or reduce invasive ventilation without reducing survival.

The response of Canada's clinical health research ecosystem to the COVID-19 pandemic.

BACKGROUND: The response of Canada's research community to the COVID-19 pandemic provides a unique opportunity to examine the country's clinical health research ecosystem. We sought to describe patterns of enrolment across Canadian Institutes of Health Research (CIHR)-funded studies on COVID-19. METHODS: We identified COVID-19 studies funded by the CIHR and that enrolled participants from Canadian acute care hospitals between January 2020 and April 2023. We collected information on study-and site-level variables from study leads, site investigators, and public domain sources. We described and evaluated factors associated with cumulative enrolment. RESULTS: We obtained information for 23 out of 26 (88%) eligible CIHR-funded studies (16 randomized controlled trials [RCTs] and 7 cohort studies). The 23 studies were managed by 12 Canadian and 3 international coordinating centres. Of 419 Canadian hospitals, 97 (23%) enrolled a total of 28 973 participants - 3876 in RCTs across 78 hospitals (median cumulative enrolment per hospital 30, interquartile range [IQR] 10-61), and 25 097 in cohort studies across 62 hospitals (median cumulative enrolment per hospital 158, IQR 6-348). Of 78 hospitals recruiting participants in RCTs, 13 (17%) enrolled 50% of all RCT participants, whereas 6 of 62 hospitals (9.7%) recruited 54% of participants in cohort studies. INTERPRETATION: A minority of Canadian hospitals enrolled the majority of participants in CIHR-funded studies on COVID-19. This analysis sheds light on the Canadian health research ecosystem and provides information for multiple key partners to consider ways to realize the full research potential of Canada's health systems.

Barriers to participation in biosampling-based translational research: A cross-sectional survey of Canadian critical care researchers.

BACKGROUND AND OBJECTIVE: Collection of biosamples for translational research studies is vital for understanding biological pathways, discovering disease-related biomarkers, and identifying novel therapeutic targets. However, a lack of infrastructure for sample procurement, processing, storage, and shipping may hinder the ability of clinical research units to effectively engage in translational research. The purpose of this study was to identify the barriers to biosampling-based translational research in the critical care setting in Canada. METHODS: We administered an online survey to members of the Canadian Critical Care Trials Group (CCCTG), the Canadian Critical Care Translational Biology Group (CCCTBG), and the Canadian Critical Care Research Coordinators Group (CCCRCG). The survey focused on participants' personal experience of biosampling research, research infrastructure, motivating factors, and perceived barriers. RESULTS: We received 59 responses from 31 sites, including 6 community intensive care unit (ICU) sites. The overall response rate was 11.3%. The majority of respondents were research coordinators (44%), followed by clinician-investigators (33.8%), graduate students (10.2%), and PhD-investigators (8.5%). Although most (63.8%) respondents reported an interest in participating in translational research, they also reported that their ICUs were currently contributing to a third of the number of translational studies compared to clinical studies. For respondents with experience in participating in translational research studies, the most common barriers were lack of funding, lack of time, and insufficient research staff. For respondents without previous experience, the perceived facilitators were more interest from their research group, improved training/mentorship, increased funding, and better access to laboratory equipment. CONCLUSIONS: Our survey found that the majority of participants were interested in and recognize the value of participating in biosampling-based translational research but lacked funding, time, and research personnel trained in biosampling protocols. Our survey also identified factors that might encourage participation at new sites. Addressing these barriers will be a key step towards increasing translational research capacity across Canada.

ICU Staffing in the United States.

BACKGROUND: The last national estimates of US ICU physician staffing are 25 years old and lack information about interprofessional teams. RESEARCH QUESTION: How are US adult ICUs currently staffed? STUDY DESIGN AND METHODS: We conducted a cross-sectional survey (May 4, 2022-February 2, 2023) of adult ICU clinicians (targeting nurse/physician leadership) contacted using 2020 American Hospital Association (AHA) database information and, secondarily, through professional organizations. The survey included questions about interprofessional ICU staffing availability and roles at steady state (pre-COVID-19). We linked survey data to hospital data in the AHA database to create weighted national estimates by extrapolating ICU staffing data to nonrespondent hospitals based on hospital characteristics. RESULTS: The cohort consisted of 596 adult ICUs (response rates: AHA contacts: 2.1%; professional organizations: unknown) with geographic diversity and size variability (median, 20 beds; interquartile range, 12-25); most cared for mixed populations (414 [69.5%]), yet medical (55 [9.2%]), surgical (70 [11.7%]), and specialty (57 [9.6%]) ICUs were well represented. A total of 554 (93.0%) had intensivists available, with intensivists covering all patients in 75.6% of these and onsite 24 h/d in one-half (53.3% weekdays; 51.8% weekends). Of all ICUs, 69.8% had physicians-in-training and 77.7% had nurse practitioners/physician assistants. For patients on mechanical ventilation, nurse to patient ratios were 1:2 in 89.6% of ICUs. Clinical pharmacists were available in 92.6%, and respiratory therapists were available in 98.8%. We estimated 85.1% (95% CI, 85.7%-84.5%) of hospitals nationally had ICUs with intensivists, 51.6% (95% CI, 50.6%-52.5%) had physicians-in-training, 72.1% (95% CI, 71.3%-72.9%) had nurse practitioners/physician assistants, 98.5% (95% CI, 98.4%-98.7%) had respiratory therapists, and 86.9% (95% CI, 86.4%-87.4%) had clinical pharmacists. For patients on mechanical ventilation, 86.4% (95% CI, 85.8%-87.0%) used 1:2 nurses/patients. INTERPRETATION: We found that intensivist presence in adult US ICUs has greatly increased over 25 years. Intensivists, respiratory therapists, and clinical pharmacists are commonly available, and each nurse usually provides care for two patients on mechanical ventilation. However, team composition and workload vary.

COVID-19 Immunologic Antiviral Therapy With Omalizumab (CIAO)-a Randomized Controlled Clinical Trial.

Background: Omalizumab is an anti-immunoglobulin E monoclonal antibody used to treat moderate to severe chronic idiopathic urticaria, asthma, and nasal polyps. Recent research suggested that omalizumab may enhance the innate antiviral response and have anti-inflammatory properties. Objective: We aimed to investigate the efficacy and safety of omalizumab in adults hospitalized for coronavirus disease 2019 (COVID-19) pneumonia. Methods: This was a phase II randomized, double blind, placebo-controlled trial comparing omalizumab with placebo (in addition to standard of care) in hospitalized patients with COVID-19. The primary endpoint was the composite of mechanical ventilation and/or death at day 14. Secondary endpoints included all-cause mortality at day 28, time to clinical improvement, and duration of hospitalization. Results: Of 41 patients recruited, 40 were randomized (20 received the study drug and 20 placebo). The median age of the patients was 74 years and 55.0% were male. Omalizumab was associated with a 92.6% posterior probability of a reduction in mechanical ventilation and death on day 14 with an adjusted odds ratio of 0.11 (95% credible interval 0.002-2.05). Omalizumab was also associated with a 75.9% posterior probability of reduced all-cause mortality on day 28 with an adjusted odds ratio of 0.49 (95% credible interval, 0.06-3.90). No statistically significant differences were found for the time to clinical improvement and duration of hospitalization. Numerically fewer adverse events were reported in the omalizumab group and there were no drug-related serious adverse events. Conclusions: These results suggest that omalizumab could prove protective against death and mechanical ventilation in hospitalized patients with COVID-19. This study could also support the development of a phase III trial program investigating the antiviral and anti-inflammatory effect of omalizumab for severe respiratory viral illnesses requiring hospital admission. ClinicalTrials.gov ID: NCT04720612.

Navigating the Landscape of Translational Geroscience in Canada: A Comprehensive Evaluation of Current Progress and Future Directions.

The inaugural Canadian Conferences on Translational Geroscience were held as 2 complementary sessions in October and November 2023. The conferences explored the profound interplay between the biology of aging, social determinants of health, the potential societal impact of geroscience, and the maintenance of health in aging individuals. Although topics such as cellular senescence, molecular and genetic determinants of aging, and prevention of chronic disease were addressed, the conferences went on to emphasize practical applications for enhancing older people's quality of life. This article summarizes the proceeding and underscores the synergy between clinical and fundamental studies. Future directions highlight national and global collaborations and the crucial integration of early-career investigators. This work charts a course for a national framework for continued innovation and advancement in translational geroscience in Canada.

Using a targeted metabolomics approach to explore differences in ARDS associated with COVID-19 compared to ARDS caused by H1N1 influenza and bacterial pneumonia.

RATIONALE: Acute respiratory distress syndrome (ARDS) is a life-threatening critical care syndrome commonly associated with infections such as COVID-19, influenza, and bacterial pneumonia. Ongoing research aims to improve our understanding of ARDS, including its molecular mechanisms, individualized treatment options, and potential interventions to reduce inflammation and promote lung repair. OBJECTIVE: To map and compare metabolic phenotypes of different infectious causes of ARDS to better understand the metabolic pathways involved in the underlying pathogenesis. METHODS: We analyzed metabolic phenotypes of 3 ARDS cohorts caused by COVID-19, H1N1 influenza, and bacterial pneumonia compared to non-ARDS COVID-19-infected patients and ICU-ventilated controls. Targeted metabolomics was performed on plasma samples from a total of 150 patients using quantitative LC-MS/MS and DI-MS/MS analytical platforms. RESULTS: Distinct metabolic phenotypes were detected between different infectious causes of ARDS. There were metabolomics differences between ARDSs associated with COVID-19 and H1N1, which include metabolic pathways involving taurine and hypotaurine, pyruvate, TCA cycle metabolites, lysine, and glycerophospholipids. ARDSs associated with bacterial pneumonia and COVID-19 differed in the metabolism of D-glutamine and D-glutamate, arginine, proline, histidine, and pyruvate. The metabolic profile of COVID-19 ARDS (C19/A) patients admitted to the ICU differed from COVID-19 pneumonia (C19/P) patients who were not admitted to the ICU in metabolisms of phenylalanine, tryptophan, lysine, and tyrosine. Metabolomics analysis revealed significant differences between C19/A, H1N1/A, and PNA/A vs ICU-ventilated controls, reflecting potentially different disease mechanisms. CONCLUSION: Different metabolic phenotypes characterize ARDS associated with different viral and bacterial infections.

Socioeconomic Status, Palliative Care, and Death at Home Among Patients With Cancer Before and During COVID-19.

Importance: The COVID-19 pandemic had a profound impact on the delivery of cancer care, but less is known about its association with place of death and delivery of specialized palliative care (SPC) and potential disparities in these outcomes. Objective: To evaluate the association of the COVID-19 pandemic with death at home and SPC delivery at the end of life and to examine whether disparities in socioeconomic status exist for these outcomes. Design, Setting, and Participants: In this cohort study, an interrupted time series analysis was conducted using Ontario Cancer Registry data comprising adult patients aged 18 years or older who died with cancer between the pre-COVID-19 (March 16, 2015, to March 15, 2020) and COVID-19 (March 16, 2020, to March 15, 2021) periods. The data analysis was performed between March and November 2023. Exposure: COVID-19-related hospital restrictions starting March 16, 2020. Main Outcomes and Measures: Outcomes were death at home and SPC delivery at the end of life (last 30 days before death). Socioeconomic status was measured using Ontario Marginalization Index area-based material deprivation quintiles, with quintile 1 (Q1) indicating the least deprivation; Q3, intermediate deprivation; and Q5, the most deprivation. Segmented linear regression was used to estimate monthly trends in outcomes before, at the start of, and in the first year of the COVID-19 pandemic. Results: Of 173 915 patients in the study cohort (mean [SD] age, 72.1 [12.5] years; males, 54.1% [95% CI, 53.8%-54.3%]), 83.7% (95% CI, 83.6%-83.9%) died in the pre-COVID-19 period and 16.3% (95% CI, 16.1%-16.4%) died in the COVID-19 period, 54.5% (95% CI, 54.2%-54.7%) died at home during the entire study period, and 57.8% (95% CI, 57.5%-58.0%) received SPC at the end of life. In March 2020, home deaths increased by 8.3% (95% CI, 7.4%-9.1%); however, this increase was less marked in Q5 (6.1%; 95% CI, 4.4%-7.8%) than in Q1 (11.4%; 95% CI, 9.6%-13.2%) and Q3 (10.0%; 95% CI, 9.0%-11.1%). There was a simultaneous decrease of 5.3% (95% CI, -6.3% to -4.4%) in the rate of SPC at the end of life, with no significant difference among quintiles. Patients who received SPC at the end of life (vs no SPC) were more likely to die at home before and during the pandemic. However, there was a larger immediate increase in home deaths among those who received no SPC at the end of life vs those who received SPC (Q1, 17.5% [95% CI, 15.2%-19.8%] vs 7.6% [95% CI, 5.4%-9.7%]; Q3, 12.7% [95% CI, 10.8%-14.5%] vs 9.0% [95% CI, 7.2%-10.7%]). For Q5, the increase in home deaths was significant only for patients who did not receive SPC (13.9% [95% CI, 11.9%-15.8%] vs 1.2% [95% CI, -1.0% to 3.5%]). Conclusions and Relevance: These findings suggest that the COVID-19 pandemic was associated with amplified socioeconomic disparities in death at home and SPC delivery at the end of life. Future research should focus on the mechanisms of these disparities and on developing interventions to ensure equitable and consistent SPC access.

Evaluating the impact of a SIMPlified LaYered consent process on recruitment of potential participants to the Staphylococcus aureus Network Adaptive Platform trial: study protocol for a multicentre pragmatic nested randomised clinical trial (SIMPLY-SNAP trial).

INTRODUCTION: Informed consent forms (ICFs) for randomised clinical trials (RCTs) can be onerous and lengthy. The process has the potential to overwhelm patients with information, leading them to miss elements of the study that are critical for an informed decision. Specifically, overly long and complicated ICFs have the potential to increase barriers to trial participation for patients with mild cognitive impairment, those who do not speak English as a first language or among those with lower medical literacy. In turn, this can influence trial recruitment, completion and external validity. METHODS AND ANALYSIS: SIMPLY-SNAP is a pragmatic, multicentre, open-label, two-arm parallel-group superiority RCT, nested within a larger trial, the Staphylococcus aureus Network Adaptive Platform (SNAP) trial. We will randomise potentially eligible participants of the SNAP trial 1:1 to a full-length ICF or a SIMPlified LaYered (SIMPLY) consent process where basic information is summarised with embedded hyperlinks to supplemental information and videos. The primary outcome is recruitment into the SNAP trial. Secondary outcomes include patient understanding of the clinical trial, patient and research staff satisfaction with the consent process, and time taken for consent. As an exploratory outcome, we will also compare measures of diversity (eg, gender, ethnicity), according to the consent process randomised to. The planned sample size will be 346 participants. ETHICS AND DISSEMINATION: The study has been approved by the ethics review board (Sunnybrook Health Sciences Research Ethics Board) at sites in Ontario. We will disseminate study results via the SNAP trial group and other collaborating clinical trial networks. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT06168474; www. CLINICALTRIALS: gov).

Association of delayed adequate antimicrobial treatment and organ dysfunction in pediatric bloodstream infections.

BACKGROUND: Bloodstream infections (BSIs) are associated with significant mortality and morbidity, including multiple organ dysfunction. We explored if delayed adequate antimicrobial treatment for children with BSIs is associated with change in organ dysfunction as measured by PELOD-2 scores. METHODS: We conducted a multicenter, retrospective cohort study of critically ill children <18 years old with BSIs. The primary outcome was change in PELOD-2 score between days 1 (index blood culture) and 5. The exposure variable was delayed administration of adequate antimicrobial therapy by ≥3 h from blood culture collection. We compared PELOD-2 score changes between those who received early and delayed treatment. RESULTS: Among 202 children, the median (interquartile range) time to adequate antimicrobial therapy was 7 (0.8-20.1) hours; 124 (61%) received delayed antimicrobial therapy. Patients who received early and delayed treatment had similar baseline characteristics. There was no significant difference in PELOD-2 score changes from days 1 and 5 between groups (PELOD-2 score difference -0.07, 95% CI -0.92 to 0.79, p = 0.88). CONCLUSIONS: We did not find an association between delayed adequate antimicrobial therapy and PELOD-2 score changes between days 1 and 5 from detection of BSI. PELOD-2 score was not sensitive for clinical effects of delayed antimicrobial treatment. IMPACT: In critically ill children with bloodstream infections, there was no significant change in organ dysfunction as measured by PELOD-2 scores between patients who received adequate antimicrobial therapy within 3 h of their initial positive blood culture and those who started after 3 h. Higher PELOD-2 scores on day 1 were associated with larger differences in PELOD-2 scores between days 1 and 5 from index positive blood cultures. Further study is required to determine if PELOD-2 or alternative measures of organ dysfunction could be used as primary outcome measures in trials of antimicrobial interventions in pediatric critical care research.

Proteomic Evolution from Acute to Post-COVID-19 Conditions.

Many COVID-19 survivors have post-COVID-19 conditions, and females are at a higher risk. We sought to determine (1) how protein levels change from acute to post-COVID-19 conditions, (2) whether females have a plasma protein signature different from that of males, and (3) which biological pathways are associated with COVID-19 when compared to restrictive lung disease. We measured protein levels in 74 patients on the day of admission and at 3 and 6 months after diagnosis. We determined protein concentrations by multiple reaction monitoring (MRM) using a panel of 269 heavy-labeled peptides. The predicted forced vital capacity (FVC) and diffusing capacity of the lungs for carbon monoxide (DLCO) were measured by routine pulmonary function testing. Proteins associated with six key lipid-related pathways increased from admission to 3 and 6 months; conversely, proteins related to innate immune responses and vasoconstriction-related proteins decreased. Multiple biological functions were regulated differentially between females and males. Concentrations of eight proteins were associated with FVC, %, and they together had c-statistics of 0.751 (CI:0.732-0.779); similarly, concentrations of five proteins had c-statistics of 0.707 (CI:0.676-0.737) for DLCO, %. Lipid biology may drive evolution from acute to post-COVID-19 conditions, while activation of innate immunity and vascular regulation pathways decreased over that period. (ProteomeXchange identifiers: PXD041762, PXD029437).

Randomized trial of the safety and efficacy of anti-SARS-CoV-2 mAb in the treatment of patients with nosocomial COVID-19 (CATCO-NOS).

Background: Patients with nosocomial acquisition of COVID-19 have poor outcomes but have not been included in therapeutic trials to date. Methods: A pragmatic open-label randomized controlled trial of anti-SARS-CoV-2 monoclonal antibodies (mAb) was performed in hospitalized patients with nosocomial COVID-19 infection in acute care hospitals spanning a provincial health care network. Participants within 5 days of first positive test or symptom onset were randomized to standard of care (SOC) plus a single dose intravenous mAb treatment (bamlanivimab or casirivimab/imdevimab) or SOC alone on a 2:1 basis. The primary study endpoint was the need for invasive mechanical ventilation (IMV) or inpatient mortality by day 60 after randomization. Results: Forty-six participants were enrolled from 13 hospitals between February 14 and October 8, 2021: 31 in the mAb and 15 in the SOC arm. IMV or inpatient mortality up to day 60 occurred in 4 (12.9%) participants in the mAb versus 3 in the SOC arm (20.0%), difference of -7.1% (95% CI -22.5 to 13.4, p = 0.67). The study was terminated early due to lack of equipoise as effectiveness of anti-viral therapies and mAb was published in similar high-risk patient populations. Conclusions: The trial was underpowered to detect meaningful differences given its early termination. The study does highlight the feasibility of undertaking trials in this patient population using a pragmatic approach allowing for trial participation and treatment access across a large health care network and may serve as a template for future designs.

Historique: Les patients qui contractent une COVID-19 nosocomiale ont de mauvais résultats cliniques, mais n'ont pas fait partie des études thérapeutiques jusqu'à présent. Méthodologie: Les chercheurs ont mené une étude randomisée et contrôlée ouverte et pragmatique des anticorps monoclonaux (AcM) anti-SRAS-CoV-2 auprès de patients hospitalisés qui ont contracté une COVID-19 nosocomiale dans les hôpitaux de soins aigus d'un réseau de santé provincial. Dans les cinq jours suivant un premier test positif ou l'apparition des symptômes, les participants ont été divisés de manière randomisée entre la norme des soins (NdS) combinée à une monodose de traitement aux AcM par voie intraveineuse (bamlanivimab ou casirivimab-imdevimab) ou la NdS seule sur une base de deux pour un. Le critère d'évaluation primaire de l'étude était la ventilation mécanique invasive (VMI) ou la mortalité en milieu hospitalier le 60e jour après la randomisation. Résultats: Au total, 46 participants de 13 hôpitaux ont été inclus entre le 14 février et le 8 octobre 2021, soit 31 patients du volet des AcM et 15 du volet de la NdS. La VMI ou la mortalité en milieu hospitalier jusqu'au 60e jour a été observée chez quatre participants au volet des AcM (12,9 %) et trois participants du volet de la NdS (20,0 %), soit une différence de −7,1 % (IC à 95 %, −22,5 à 13,4, p = 0,67). L'étude a été interrompue précocement à cause de l'absence d'équilibre clinique, car des données sur l'efficacité des traitements antiviraux et des AcM ont été publiées au sujet de populations semblables de patients à haut risque. Conclusions: L'échantillon à l'étude était insuffisant pour déceler des différences significatives compte tenu de son interruption précoce. Cette recherche fait ressortir la faisabilité d'études auprès de cette population de patients au moyen d'une approche pragmatique pour y inclure des participants et accéder au traitement dans un vaste réseau de soins et pourrait servir de modèle pour concevoir d'autres études.

Persistent post-COVID headache is associated with suppression of scale-free functional brain dynamics in non-hospitalized individuals.

INTRODUCTION: Post-acute coronavirus disease 2019 (COVID-19) syndrome (PACS) is a growing concern, with headache being a particularly debilitating symptom with high prevalence. The long-term effects of COVID-19 and post-COVID headache on brain function remain poorly understood, particularly among non-hospitalized individuals. This study focused on the power-law scaling behavior of functional brain dynamics, indexed by the Hurst exponent (H). This measure is suppressed during physiological and psychological distress and was thus hypothesized to be reduced in individuals with post-COVID syndrome, with greatest reductions among those with persistent headache. METHODS: Resting-state blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging data were collected for 57 individuals who had COVID-19 (32 with no headache, 14 with ongoing headache, 11 recovered) and 17 controls who had cold and flu-like symptoms but  tested negative for COVID-19. Individuals were assessed an average of 4-5 months after COVID testing, in a cross-sectional, observational study design. RESULTS: No significant differences in H values were found between non-headache COVID-19 and control groups., while those with ongoing headache had significantly reduced H values, and those who had recovered from headache had elevated H values, relative to non-headache groups. Effects were greatest in temporal, sensorimotor, and insular brain regions. Reduced H in these regions was also associated with decreased BOLD activity and local functional connectivity. CONCLUSIONS: These findings provide new insights into the neurophysiological mechanisms that underlie persistent post-COVID headache, with reduced BOLD scaling as a potential biomarker that is specific to this debilitating condition.

Outcomes and characteristics of patients hospitalized for COVID-19 in British Columbia, Ontario and Quebec during the Omicron wave.

BACKGROUND: Omicron is the current predominant variant of concern of SARS-CoV-2. We hypothesized that vaccination alters outcomes of patients hospitalized with COVID-19 during the Omicron wave and that these patients have different characteristics and outcomes than in previous waves. METHODS: This is a substudy of the Host Response Mediators in Coronavirus (COVID-19) Infection (ARBs CORONA I) trial, which included adults admitted to hospital with acute COVID-19 up to July 2022 from 9 hospitals in British Columbia, Ontario and Quebec. We excluded emergency department visits without hospital admission, readmissions and admissions for another reason. Using adjusted regression analysis, we compared mortality and organ dysfunction between vaccinated (≥ 2 doses) and unvaccinated patients during the Omicron wave, as well as between all patients in the Omicron and first 3 waves of the COVID-19 pandemic. RESULTS: During the Omicron wave, 28-day mortality was significantly lower in vaccinated (n = 19/237) than unvaccinated hospitalized patients (n = 12/127) (adjusted odds ratio [OR] 0.36, 95% confidence interval [CI] 0.15-0.89); vaccinated patients had lower risk of admission to the intensive care unit, invasive ventilation and acute respiratory distress syndrome and shorter hospital length of stay. Patients hospitalized during the Omicron wave had more comorbidities than in previous waves, and lower 28-day mortality than in waves 1 and 2 (adjusted OR 0.38, 95% CI 0.24-0.59; and 0.42, 95% CI 0.26-0.65) but not wave 3 (adjusted OR 0.81, 95% CI 0.43-1.51) and had less organ dysfunction than in the first 2 waves. INTERPRETATION: Patients who were at least double vaccinated had lower mortality than unvaccinated patients hospitalized during the Omicron wave. Patients hospitalized during the Omicron wave had more chronic disease and lower mortality than in the first 2 waves, but not wave 3. Changes in vaccination, treatments and predominant SARS-CoV-2 variant may have decreased mortality in patients hospitalized during the Omicron wave.

Fixed versus individualized treatment for five common bacterial infectious syndromes: a survey of the perspectives and practices of clinicians.

Background: Traditionally, bacterial infections have been treated with fixed-duration antibiotic courses; however, some have advocated for individualized durations. It is not known which approach currently predominates. Methods: We conducted a multinational clinical practice survey asking prescribers their approach to treating skin and soft tissue infection (SSTI), community-acquired pneumonia (CAP), pyelonephritis, cholangitis and bloodstream infection (BSI) of an unknown source. The primary outcome was self-reported treatment approach as being fully fixed duration, fixed minimum, fixed maximum, fixed minimum and maximum, or fully individualized durations. Secondary questions explored factors influencing duration of therapy. Multivariable logistic regression with generalized estimating equations was used to examine predictors of use of fully fixed durations. Results: Among 221 respondents, 170 (76.9%) completed the full survey; infectious diseases physicians accounted for 60.6%. Use of a fully fixed duration was least common for SSTI (8.5%) and more common for CAP (28.3%), BSI (29.9%), cholangitis (35.7%) and pyelonephritis (36.3%). Fully individualized therapy, with no fixed minimum or maximum, was used by only a minority: CAP (4.9%), pyelonephritis (5.0%), cholangitis (9.9%), BSI (13.6%) and SSTI (19.5%). In multivariable analyses, a fully fixed duration approach was more common among Canadian respondents [adjusted OR (aOR) 1.76 (95% CI 1.12-2.76)] and for CAP (aOR 4.25, 95% CI 2.53-7.13), cholangitis (aOR 6.01, 95% CI 3.49-10.36), pyelonephritis (aOR 6.08, 95% CI 3.56-10.39) and BSI (aOR 4.49, 95% CI 2.50-8.09) compared with SSTI. Conclusions: There is extensive practice heterogeneity in fixed versus individualized treatment; clinical trials would be helpful to compare these approaches.