Higher vs lower doses of dexamethasone in patients with COVID-19 and severe hypoxia (COVID STEROID 2) trial: Protocol and statistical analysis plan.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has resulted in millions of deaths and overburdened healthcare systems worldwide. Systemic low-dose corticosteroids have proven clinical benefit in patients with severe COVID-19. Higher doses of corticosteroids are used in other inflammatory lung diseases and may offer additional clinical benefits in COVID-19. At present, the balance between benefits and harms of higher vs. lower doses of corticosteroids for patients with COVID-19 is unclear. METHODS: The COVID STEROID 2 trial is an investigator-initiated, international, parallel-grouped, blinded, centrally randomised and stratified clinical trial assessing higher (12 mg) vs. lower (6 mg) doses of dexamethasone for adults with COVID-19 and severe hypoxia. We plan to enrol 1,000 patients in Denmark, Sweden, Switzerland and India. The primary outcome is days alive without life support (invasive mechanical ventilation, circulatory support or renal replacement therapy) at day 28. Secondary outcomes include serious adverse reactions at day 28; all-cause mortality at day 28, 90 and 180; days alive without life support at day 90; days alive and out of hospital at day 90; and health-related quality of life at day 180. The primary outcome will be analysed using the Kryger Jensen and Lange test adjusted for stratification variables and reported as adjusted mean differences and median differences. The full statistical analysis plan is outlined in this protocol. DISCUSSION: The COVID STEROID 2 trial will provide evidence on the optimal dosing of systemic corticosteroids for COVID-19 patients with severe hypoxia with important implications for patients, their relatives and society.

Recovery after acute illness after hospital discharge - a prospective cohort study.

BACKGROUND: Long-term outcomes after acute medical and surgical illness are largely unknown. AIM: To describe cognitive and physical function, health-related quality of life and risk of anxiety and depression after acute illness. DESIGN: Prospective cohort study. METHODS: Home visit at three and twelve months measuring: Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Chelsea Critical Care Physical Assessment tool, Short Form Health Survey, Hospital Anxiety and Depression Scale and Trail Making Test. RESULTS: Of 101 included patients, 60 were visited at three and 36 at twelve months. The RBANS value was 84 (69-96) at three months and 88 (69-101) at twelve months. CONCLUSIONS: We found a moderately reduced cognitive function three and twelve months after acute illness.

Intensive care doctors' preferences for arterial oxygen tension levels in mechanically ventilated patients.

BACKGROUND: Oxygen is liberally administered in intensive care units (ICUs). Nevertheless, ICU doctors' preferences for supplementing oxygen are inadequately described. The aim was to identify ICU doctors' preferences for arterial oxygenation levels in mechanically ventilated adult ICU patients. METHODS: In April to August 2016, an online multiple-choice 17-part-questionnaire was distributed to 1080 ICU doctors in seven Northern European countries. Repeated reminder e-mails were sent. The study ended in October 2016. RESULTS: The response rate was 63%. When evaluating oxygenation 52% of respondents rated arterial oxygen tension (PaO2 ) the most important parameter; 24% a combination of PaO2 and arterial oxygen saturation (SaO2 ); and 23% preferred SaO2 . Increasing, decreasing or not changing a default fraction of inspired oxygen of 0.50 showed preferences for a PaO2 around 8 kPa in patients with chronic obstructive pulmonary disease, a PaO2 around 10 kPa in patients with healthy lungs, acute respiratory distress syndrome or sepsis, and a PaO2 around 12 kPa in patients with cardiac or cerebral ischaemia. Eighty per cent would accept a PaO2 of 8 kPa or lower and 77% would accept a PaO2 of 12 kPa or higher in a clinical trial of oxygenation targets. CONCLUSION: Intensive care unit doctors preferred PaO2 to SaO2 in monitoring oxygen treatment when peripheral oxygen saturation was not included in the question. The identification of PaO2 as the preferred target and the thorough clarification of preferences are important when ascertaining optimal oxygenation targets. In particular when designing future clinical trials of higher vs lower oxygenation targets in ICU patients.

Delirium and effect of circadian light in the intensive care unit: a retrospective cohort study.

BACKGROUND: Delirium is a serious condition often experienced by critically ill patients in intensive care units (ICUs). The role of circadian light for this condition is unclear. The aim of this study was to describe incidence of delirium, risk factors for delirium, and the association between delirium and circadian light for patients in the ICU. METHODS: This is a retrospective cohort study of all patients at a Danish ICU from 1 August 2015 to 31 January 2016. Exclusion criteria were heavy sedation, no Confusion Assessment Method for the ICU (CAM-ICU) scores, or inability to communicate in Danish. Delirium was defined as at least one positive CAM-ICU score or treatment with haloperidol. Three of nine beds at the ICU had a circadian light installation. Allocation to ICU beds with or without circadian light depended on availability at admission. Risk factors for development of delirium were analyzed by simple and multiple logistic regression. RESULTS: We included 183 patients in the study. The incidence of delirium was 28% (95% CI 22, 35). Allocation to beds with or without circadian lighting was not associated with delirium incidence (OR 1.14; 95% CI 0.55, 2.37; P = 0.73). We found that Simplified Acute Physiology Score II (SAPS II) (OR 1.03; 95% CI 1.01, 1.06; P = 0.002), and dexmedetomidine was associated with delirium (OR 4.14; 95% CI 1.72, 10.03; P = 0.002). CONCLUSION: In this population of patients admitted to an ICU during 6 months, the incidence of delirium was 28%. We did not find an association between circadian light and development of delirium.

Follow-up after intensive care treatment: a questionnaire survey of intensive care aftercare in Denmark.

BACKGROUND: Rehabilitation efforts after treatment in the intensive care unit (ICU) are termed intensive care aftercare. It includes both early in-hospital follow-up after ICU-discharge and late follow-up after hospital discharge. This study aims to investigate the current ICU-aftercare activities in Denmark. METHODS: We conducted an electronic questionnaire survey, which was distributed by e-mail to the heads of all 31 general ICUs in Denmark. Specialized ICUs were not included. The questionnaire was divided into the following sections: early ICU-aftercare, late ICU-aftercare, future development and demographics. RESULTS: Thirty-one ICUs were invited to participate. The response rate was 100%. Overall, 26 of 31 ICUs (84%) offered ICU-aftercare, with the following distribution: early ICU-aftercare (58%), late ICU-aftercare (57%) and both (29%). There were no significant associations between hospital size and provision of ICU-aftercare. For early ICU-aftercare, the most common eligibility criteria were based on ICU length of stay (LOS) (44%) and a decision based upon doctors' discretion (22%). Incidence of guidelines for early ICU-aftercare (44%) and checklists at patient contact (35%) were sparse. The most common early ICU-aftercare items were as follows: respiratory care (82%), tracheostomy care (59%) and nutritional care (59%). For late ICU-aftercare, the most common eligibility criterion was LOS (41%). Guidelines (71%), but not checklist at patient contact (35%), were more common. Most frequent late ICU-aftercare interventions were review of ICU-diaries (59%) and patient charts (53%). CONCLUSION: Eighty-four per cent of Danish ICUs offered ICU-aftercare to their patients. There was an abundant heterogeneity of eligibility criteria and ICU-aftercare interventions.

Identification of cytotoxic T cell epitopes within Epstein-Barr virus (EBV) oncogene latent membrane protein 1 (LMP1): evidence for HLA A2 supertype-restricted immune recognition of EBV-infected cells by LMP1-specific cytotoxic T lymphocytes.

Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) and latent membrane proteins (LMP) are the only antigens consistently expressed in malignancies such as nasopharyngeal carcinoma (NPC) and Hodgkin's disease (HD). Since EBNA1 is not recognized by EBV-specific cytotoxic T lymphocytes (CTL), there is increasing interest in the identification of the potential target epitopes within LMP1. Although LMP1-specific CTL have been isolated from seropositive individuals, earlier attempts to identify the peptide epitopes recognized by these T cells have been unsuccessful. In the present report we used a novel protocol to identify CTL epitopes within LMP1 which can be recognized by both polyclonal and clonal CTL. Firstly, a computer-based program was employed to identify the potential HLA-binding peptides within LMP1. Polyclonal CD8+ CTL were then isolated from seropositive donors that recognized the peptide epitopes YLLEMLWRL and YLQQNWWTL from LMP1 in association with HLA A2. Limiting dilution analysis of the memory CTL response revealed that the LMP1-specific CTL response constitutes a minor component of the CTL response in healthy virus carriers. Interestingly, analysis of YLLEMLWRL-specific CTL revealed that these CTL were able to lyse EBV-infected B cells expressing different HLA A2 supertype alleles including A*0201, A*0202, A*0203, A*0204, A*0206, A*6802 and A*6901. These data strongly support the notion that HLA class I supertype-restricted CTL may be of significant use in the development of peptide-based immunotherapeutics against EBV-associated malignancies in different ethnic populations.

Class I processing-defective Burkitt's lymphoma cells are recognized efficiently by CD4+ EBV-specific CTLs.

In the present study, we have isolated CD4+ CTLs that recognize an epitope from EBV nuclear Ag 2 in association with two different HLA-DQ Ags, DQA1*0501/DQB1*0201 (DQ2) or DQA1*0501/DQB1*0301 (DQ7). Both the HLA-DQ2 and HLA-DQ7 alleles displayed a similar efficiency in the endogenous and exogenous presentation of this epitope. Since earlier studies have shown that the EBV-associated malignancy, Burkitt's lymphoma (BL), escapes class I-restricted immune recognition by down-regulating the expression of peptide transporter genes, we have explored the possibility that these tumor cells can process class II-restricted CTL epitopes. The data presented in this study clearly demonstrate that BL cells were recognized efficiently by CD4+, MHC class II-restricted EBV-specific CTLs following infection with recombinant vaccinia encoding EBV nuclear Ag 2. Analysis of surface MHC class II expression on BL cells revealed high levels of HLA-DR and HLA-DQ molecules, and most of these molecules were negative for the invariant chain peptide, referred to as CLIP. Moreover, these tumor cells also showed normal levels of HLA-DMB gene expression, which has been shown previously to be an essential component of the class II processing pathway. The present finding of efficient processing function through the class II pathway in BL cells provides a novel mechanism for immune targeting of EBV-positive malignancies.

Cytotoxic T-lymphocyte clones specific for an immunodominant epitope display discerning antagonistic response to naturally occurring Epstein-Barr virus variants.

In the present study we have identified Epstein-Barr virus isolates which encode variant sequences within an HLA B35-restricted immunodominant cytotoxic T-lymphocyte (CTL) epitope that act as natural antagonists and can inhibit CTL activity on the wild-type epitope. This effect can be demonstrated if the wild-type epitope is presented as a synthetic peptide or when processed from a full-length Epstein-Barr virus protein expressed by recombinant vaccinia constructs. However, this antagonistic effect was only selectively seen with some CTL clones, while a strong agonistic effect was evident for other clones in the presence of the same variant peptide. The data presented in this study strongly suggest that it is unlikely that the variant viruses can completely antagonize a virus-specific CTL response by this mechanism since the host immune response is capable of generating CTLs expressing a diverse array of T-cell receptors. Moreover, many of these CTLs can recognize the variant sequences as efficiently as wild-type epitope.

Unusually high frequency of Epstein-Barr virus genetic variants in Papua New Guinea that can escape cytotoxic T-cell recognition: implications for virus evolution.

Cytotoxic T lymphocytes (CTLs) which recognize viral antigens in association with human leukocyte antigens (HLAs) play an important role in controlling persistent virus infections. These viruses use several mechanisms to evade the immune response, including mutations that affect either T-cell receptor recognition or binding of viral epitopes to the HLA. It has recently been proposed that the distribution of HLA frequencies and the specific CTL response may influence the long-term evolution of Epstein-Barr virus (EBV) by selecting variants which lack immunodominant CTL epitopes. To test this hypothesis, we have studied EBV isolates from two genetically distinct Papua New Guinea (PNG) populations, residing in coastal and highland regions, for polymorphism within seven viral CTL epitope sequences restricted through several class I HLAs. Surprisingly, all EBV isolates analyzed displayed identical amino acid substitutions within HLA A11-, B35- and B8-restricted CTL epitope sequences which completely abrogated CTL recognition and binding of synthetic peptides to HLA molecules. Furthermore, these substitutions revealed no correlation with the contemporary distribution of HLAs in the different PNG populations, which argues for a minimal influence of immune pressure. The sequence homology between EBV isolates from coastal and highland PNG suggests that the virus may have had a single origin and, more importantly, that these isolates are genetically distinct from those present in a Caucasian population.