Gut Symptoms, Gut Dysbiosis and Gut-Derived Toxins in ALS

Many pathogenetic mechanisms have been proposed for amyotrophic lateral sclerosis (ALS). Recently, there have been emerging suggestions of a possible role for the gut microbiota. Gut microbiota have a range of functions and could influence ALS by several mechanisms. Here, we review the possible role of gut-derived neurotoxins/excitotoxins. We review the evidence of gut symptoms and gut dysbiosis in ALS. We then examine a possible role for gut-derived toxins by reviewing the evidence that these molecules are toxic to the central nervous system, evidence of their association with ALS, the existence of biochemical pathways by which these molecules could be produced by the gut microbiota and existence of mechanisms of transport from the gut to the blood and brain. We then present evidence that there are increased levels of these toxins in the blood of some ALS patients. We review the effects of therapies that attempt to alter the gut microbiota or ameliorate the biochemical effects of gut toxins. It is possible that gut dysbiosis contributes to elevated levels of toxins and that these could potentially contribute to ALS pathogenesis, but more work is required.

Clinician perceptions of research priorities for the management of noncritically ill patients admitted to hospital with SARS-CoV-2 infection

The changing phenotype of coronarvirus disease 2019 (COVID-19) may quickly render guideline-recommended interventions obsolete. We developed a 40-question clinician survey in consultation with the Australasian COVID-19 Trial site investigators. The survey was designed to assess clinician perceptions of the current treatment strategies and future research priorities in the management of non-critically ill patients admitted to hospital with SARS-CoV-2 infection. There were 84 complete responses from predominantly Australian and New Zealand clinicians. The perceived prevalence of patients with incidental COVID-19, nosocomial infection, underlying illness exacerbated by COVID-19, and/or immunocompromised status suggests new populations to target. The results highlighted clinician interest in antiviral therapies for future research in both immunocompetent and immunocompromised cohorts. These survey results underscore the need for ongoing surveillance of COVID-19 disease phenotypes and clinician and patient priorities for future research.

A physiotherapy group exercise and self-management approach to improve physical activity in people with mild-moderate Parkinson's disease: a randomized controlled trial

BACKGROUND

Physical activity levels are low in people with Parkinson's disease (PD) and have proved difficult to increase with exercise programs alone. Intervention approaches that address both the capacity to engage in physical activity and self-management strategies to change and maintain exercise behaviours are needed to address this intractable issue.

METHODS

This will be an assessor-blinded, randomized controlled trial performed in Brisbane, Australia. Ninety-two people with mild-moderate PD will be randomly allocated to two groups: usual care, and a physiotherapy-led group exercise program combined with self-management strategies. In the intervention group, twelve, 80-min sessions will be conducted over 4 weeks in groups of up to 4 participants. The intervention will consist of circuit training including treadmill walking to target aerobic fitness, and activities targeting strength, balance, and gait performance. In addition, each session will also incorporate strategies focusing on self-management and behaviour change, augmented by the provision of a fitness activity tracker. Outcome measures will be collected at baseline (T1), immediately post intervention (T2) and at 6 months follow-up (T3). The primary outcome measure is free-living physical activity (average daily step count over 7 days) at pre (T1) and post (T2) intervention measured using an activPAL™ device. Secondary outcome measures captured at all time points include time spent walking, sedentary and in moderate intensity exercise over 7 days; spatiotemporal gait performance (step length, gait speed, endurance); health-related quality of life; and outcome expectations and self-efficacy for exercise.

DISCUSSION

Sustainability of gains in physical activity following exercise interventions is a challenge for most populations. Our incorporation of a chronic disease self-management approach into the exercise program including fitness tracking extends previous trials and has potential to significantly improve free-living physical activity in people with PD.

TRIAL REGISTRATION

This study has been prospectively registered in Australian and New Zealand Clinical Trial Registry (ACTRN12617001057370), registered on 19/07/2017. Available from www.anzctr.org.au/ACTRN12617001057370.aspx .

Hydroxychloroquine plus personal protective equipment versus personal protective equipment alone for the prevention of laboratory-confirmed COVID-19 infections among healthcare workers: a multicentre, parallel-group randomised controlled trial from India

OBJECTIVES

To determine whether hydroxychloroquine when used with personal protective equipment reduces the proportion of laboratory-confirmed COVID-19 among healthcare workers in comparison to the use of personal protective equipment alone.

DESIGN

Multicentre, parallel-group, open-label randomised trial. Enrolment started on 29 June 2020 and stopped on 4 February 2021. Participants randomised in HydrOxychloroquine Prophylaxis Evaluation were followed for 6 months.

SETTING

9 hospitals across India.

PARTICIPANTS

Healthcare workers in an environment with exposure to COVID-19 were randomised in a 1:1 ratio to hydroxychloroquine plus use of personal protective equipment or personal protective equipment alone. 886 participants were screened and 416 randomised (213 hydroxychloroquine arm and 203 personal protective equipment).

INTERVENTION

Participants in intervention arm received 800 mg of hydroxychloroquine on day of randomisation and then 400 mg once a week for 12 weeks in addition to the use of personal protective equipment. In the control arm, participants continued to use personal protective equipment alone.

MAIN OUTCOME

Proportion of laboratory-confirmed COVID-19 in the 6 months after randomisation.

RESULTS

Participants were young (mean age 32.1 years, SD 9.1 years) with low-comorbid burden. 47.4% were female. In the 6 months after randomisation (primary analysis population=413), 11 participants assigned to the hydroxychloroquine group and 12 participants assigned to the standard practice group met the primary endpoint (5.2% vs 5.9%; OR 0.85, 95% CI 0.35 to 2.07, p=0.72). There was no heterogeneity of treatment effect in any prespecified subgroup. There were no significant differences in the secondary outcomes. The adverse event rates were 9.9% and 6.9% in the hydroxychloroquine and standard practice arms, respectively. There were no serious adverse events in either group.

CONCLUSIONS AND RELEVANCE

Hydroxychloroquine along with personal protective equipment was not superior to personal protective equipment alone on the proportion of laboratory-confirmed COVID-19. Definitive conclusions are precluded as the trial stopped early for futility, and hence was underpowered.

TRIAL REGISTRATION NUMBER

CTRI/2020/05/025067.

Early short course of neuromuscular blocking agents in patients with COVID-19 ARDS: a propensity score analysis

BACKGROUND

The role of neuromuscular blocking agents (NMBAs) in coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) is not fully elucidated. Therefore, we aimed to investigate in COVID-19 patients with moderate-to-severe ARDS the impact of early use of NMBAs on 90-day mortality, through propensity score (PS) matching analysis.

METHODS

We analyzed a convenience sample of patients with COVID-19 and moderate-to-severe ARDS, admitted to 244 intensive care units within the COVID-19 Critical Care Consortium, from February 1, 2020, through October 31, 2021. Patients undergoing at least 2 days and up to 3 consecutive days of NMBAs (NMBA treatment), within 48 h from commencement of IMV were compared with subjects who did not receive NMBAs or only upon commencement of IMV (control). The primary objective in the PS-matched cohort was comparison between groups in 90-day in-hospital mortality, assessed through Cox proportional hazard modeling. Secondary objectives were comparisons in the numbers of ventilator-free days (VFD) between day 1 and day 28 and between day 1 and 90 through competing risk regression.

RESULTS

Data from 1953 patients were included. After propensity score matching, 210 cases from each group were well matched. In the PS-matched cohort, mean (± SD) age was 60.3 ± 13.2 years and 296 (70.5%) were male and the most common comorbidities were hypertension (56.9%), obesity (41.1%), and diabetes (30.0%). The unadjusted hazard ratio (HR) for death at 90 days in the NMBA treatment vs control group was 1.12 (95% CI 0.79, 1.59, p = 0.534). After adjustment for smoking habit and critical therapeutic covariates, the HR was 1.07 (95% CI 0.72, 1.61, p = 0.729). At 28 days, VFD were 16 (IQR 0-25) and 25 (IQR 7-26) in the NMBA treatment and control groups, respectively (sub-hazard ratio 0.82, 95% CI 0.67, 1.00, p = 0.055). At 90 days, VFD were 77 (IQR 0-87) and 87 (IQR 0-88) (sub-hazard ratio 0.86 (95% CI 0.69, 1.07; p = 0.177).

CONCLUSIONS

In patients with COVID-19 and moderate-to-severe ARDS, short course of NMBA treatment, applied early, did not significantly improve 90-day mortality and VFD. In the absence of definitive data from clinical trials, NMBAs should be indicated cautiously in this setting.

An appraisal of respiratory system compliance in mechanically ventilated covid-19 patients

BACKGROUND

Heterogeneous respiratory system static compliance (CRS) values and levels of hypoxemia in patients with novel coronavirus disease (COVID-19) requiring mechanical ventilation have been reported in previous small-case series or studies conducted at a national level.

METHODS

We designed a retrospective observational cohort study with rapid data gathering from the international COVID-19 Critical Care Consortium study to comprehensively describe CRS-calculated as: tidal volume/[airway plateau pressure-positive end-expiratory pressure (PEEP)]-and its association with ventilatory management and outcomes of COVID-19 patients on mechanical ventilation (MV), admitted to intensive care units (ICU) worldwide.

RESULTS

We studied 745 patients from 22 countries, who required admission to the ICU and MV from January 14 to December 31, 2020, and presented at least one value of CRS within the first seven days of MV. Median (IQR) age was 62 (52-71), patients were predominantly males (68%) and from Europe/North and South America (88%). CRS, within 48 h from endotracheal intubation, was available in 649 patients and was neither associated with the duration from onset of symptoms to commencement of MV (p = 0.417) nor with PaO2/FiO2 (p = 0.100). Females presented lower CRS than males (95% CI of CRS difference between females-males: - 11.8 to - 7.4 mL/cmH2O p < 0.001), and although females presented higher body mass index (BMI), association of BMI with CRS was marginal (p = 0.139). Ventilatory management varied across CRS range, resulting in a significant association between CRS and driving pressure (estimated decrease - 0.31 cmH2O/L per mL/cmH20 of CRS, 95% CI - 0.48 to - 0.14, p < 0.001). Overall, 28-day ICU mortality, accounting for the competing risk of being discharged within the period, was 35.6% (SE 1.7). Cox proportional hazard analysis demonstrated that CRS (+ 10 mL/cm H2O) was only associated with being discharge from the ICU within 28 days (HR 1.14, 95% CI 1.02-1.28, p = 0.018).

CONCLUSIONS

This multicentre report provides a comprehensive account of CRS in COVID-19 patients on MV. CRS measured within 48 h from commencement of MV has marginal predictive value for 28-day mortality, but was associated with being discharged from ICU within the same period. Trial documentation: Available at https://www.covid-critical.com/study .

TRIAL REGISTRATION

ACTRN12620000421932.

Incremental role of CT coronary angiography in the assessment of left ventricular diastolic function

OBJECTIVE

To determine whether Computed Tomography (CT) coronary angiography (CTCA) has clinical value for the assessment of left ventricular (LV) diastolic dysfunction (DD) beyond traditional information on coronary artery anatomy.

METHOD

In this retrospective study, a consecutive group of 72 patients (mean age 59±13 years)-who met the eligibility criteria of sinus rhythm, no significant valvular abnormalities, and who had transthoracic echocardiogram (TTE)-were analysed. The CTCA was prospectively triggered during diastole. Outcomes of interest were CTCA derived LV and left atrial (LA) volumes, diastolic expansion (DE) index: LV volume÷LA volume and DE fraction (DEF): [(LV volume-LA volume)÷LV volume]×100. TTE-LA volume was measured as maximum, minimum and pre-A. Studied patients were divided according to the current classification of LVDD as a reference standard. A small subgroup of nine patients underwent further invasive cardiac catheterisation.

RESULTS

CTCA-LV and LA volumes were larger compared with TTE, 37%±20% and 11%±21%, respectively. CTCA-LA volume correlated well with all TTE-LA volumes (maximum: R2=0.58; pre-A wave: R2=0.39; minimum: R2=0.26; p<0.0001) with the smallest differences in maximum LA volume (9±32 mL; mean±2 SD). The DE and DEF correlated with both LA function and LVDD. DE >1.65 and DE <1.40 have good specificity (85% and 88%, respectively), and positive predictive value to differentiate LVDD. DE and DEF were dependent on the patients' age but independent of other variables.

CONCLUSIONS

CTCA derived diastasis volume indices can provide additional quantifiable information on LVDD.

Design and rationale of the COVID-19 Critical Care Consortium international, multicentre, observational study

INTRODUCTION

There is a paucity of data that can be used to guide the management of critically ill patients with COVID-19. In response, a research and data-sharing collaborative-The COVID-19 Critical Care Consortium-has been assembled to harness the cumulative experience of intensive care units (ICUs) worldwide. The resulting observational study provides a platform to rapidly disseminate detailed data and insights crucial to improving outcomes.

METHODS AND ANALYSIS

This is an international, multicentre, observational study of patients with confirmed or suspected SARS-CoV-2 infection admitted to ICUs. This is an evolving, open-ended study that commenced on 1 January 2020 and currently includes >350 sites in over 48 countries. The study enrols patients at the time of ICU admission and follows them to the time of death, hospital discharge or 28 days post-ICU admission, whichever occurs last. Key data, collected via an electronic case report form devised in collaboration with the International Severe Acute Respiratory and Emerging Infection Consortium/Short Period Incidence Study of Severe Acute Respiratory Illness networks, include: patient demographic data and risk factors, clinical features, severity of illness and respiratory failure, need for non-invasive and/or mechanical ventilation and/or extracorporeal membrane oxygenation and associated complications, as well as data on adjunctive therapies.

ETHICS AND DISSEMINATION

Local principal investigators will ensure that the study adheres to all relevant national regulations, and that the necessary approvals are in place before a site may contribute data. In jurisdictions where a waiver of consent is deemed insufficient, prospective, representative or retrospective consent will be obtained, as appropriate. A web-based dashboard has been developed to provide relevant data and descriptive statistics to international collaborators in real-time. It is anticipated that, following study completion, all de-identified data will be made open access.

TRIAL REGISTRATION NUMBER

ACTRN12620000421932 (http://anzctr.org.au/ACTRN12620000421932.aspx).

Hydroxychloroquine plus personal protective equipment versus standard personal protective equipment alone for the prevention of COVID-19 infections among frontline healthcare workers: the HydrOxychloroquine Prophylaxis Evaluation(HOPE) trial: A structured summary of a study protocol for a randomized controlled trial

OBJECTIVES

To evaluate the effect of the combination of hydroxychloroquine (HCQ) and standard personal protective equipment (PPE) compared to the use of standard personal protective equipment alone on the proportion of laboratory confirmed COVID-19 infections among frontline healthcare workers(HCWs) in India TRIAL DESIGN: HOPE is an investigator initiated multi-centre open-label parallel group randomized controlled trial.

PARTICIPANTS

All HCWs currently working in an environment with direct exposure to patients with confirmed COVID-19 infection are eligible to participate in the trial. The trial aims to be conducted across 20-30 centres (public and private hospitals) in India. HCWs who decline consent, who have a confirmed COVID-19 infection, those who are already on chloroquine/HCQ for any indication, or if pregnant or breast-feeding, or have known QT prolongation or are on medications that when taken with HCQ can prolong the QTc will be excluded.

INTERVENTION AND COMPARATOR

The interventions to be compared in this trial are standard practice (use of recommended PPE) and HCQ plus standard practice. In the standard practice arm, HCWs will use recommended PPE as per institutional guidelines and based on their roles. They will be discouraged from taking HCQ to prevent contamination and contacted every week for the duration of the study to ascertain if they have taken any HCQ. Any such use will be reported as a protocol violation. In the intervention arm, HCWs will be administered 800mg of HCQ as a loading dose on the day of randomization (as two 400mg doses 12hrs apart) and subsequently continued on 400mg once a week for 12 weeks. This will be in addition to the use of recommended PPE as per institutional guidelines and based on their roles. HCWs will collect the drug once every week from designated research and pharmacy staff at site. A weekly phone reminder will be provided to participants in this arm to ensure compliance. An ECG will be performed between 4-6 weeks in this arm and if the QTc is prolonged (greater than 450milliseconds), the drug will be stopped. Follow-up will however continue. Participants in both arms will receive a weekly phone call for evaluation of the primary outcome, to monitor protocol compliance and development of any adverse events (in the HCQ group).

MAIN OUTCOMES

Participants will be followed on a weekly basis. The primary outcome is the proportion of HCWs developing laboratory confirmed COVID-19 infection within 6 months of randomization. We will also evaluate a number of secondary outcomes, including hospitalization related to suspected/confirmed COVID-19 infection, intensive care unit or high-dependency unit admission due to suspected/confirmed COVID-19 infection, all-cause mortality, need for organ support ( non-invasive or invasive ventilation, vasopressors and renal replacement therapy), ICU and hospital length of stay, readmission, days off work and treatment-related adverse events.

RANDOMISATION

Randomisation will be conducted through a password-protected, secure website using a central, computer-based randomisation program. Randomisation will be stratified by participating institutions and by the role of HCW - nursing, medical and other. Participants will be randomised 1:1 to either standard practice only or HCQ plus standard practice. Allocation concealment is maintained by central web-based randomisation BLINDING (MASKING): This is an unblinded study: study assigned treatment will be known to the research team and participant. Bias will be mitigated through an objective end point (laboratory confirmed COVID-19 infection).

NUMBERS TO BE RANDOMISED (SAMPLE SIZE)

A total of 6,950 HCWs will be enrolled (3475 to the intervention) and (3475 to the standard practice group) to detect a 25% relative reduction, or 2.5% absolute reduction, in the infection rate from an estimated baseline infection rate of 10%, with 80% statistical power using a two-sided test at 5% level of significance. Available data from China and Italy indicate that the rate of infection among frontline healthcare workers varies between 4% to 12%. We therefore assumed a baseline infection rate of 10% among HCWs. This sample size allows for a potential loss to follow-up rate of 10% and a potential non-compliance rate of 10% in both the treatment and control arms.

TRIAL STATUS

HOPE protocol version 3.0 dated June 3rd 2020. Recruitment started on 29th June 2020 and currently 56 participants have been enrolled. Planned completion of enrolment is January 31st 2021.

TRIAL REGISTRATION

Clinical Trials Registry of India: CTRI/2020/05/025067 (prospectively registered) Date of registration: 6th May 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expedited dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

Effect of High-Intensity Interval Training on Visceral and Liver Fat in Cardiac Rehabilitation: A Randomized Controlled Trial

OBJECTIVE

This study aimed to investigate the effect of exercise intensity on visceral adipose tissue (VAT) and liver fat reduction in patients with coronary artery disease (CAD) over 3 months and the maintenance of improvements over 12 months.

METHODS

Forty-two participants with CAD were randomized to three sessions/week of either 4 × 4-minute high-intensity interval training (HIIT) or 40 minutes of usual care moderate-intensity continuous training (MICT) for a 4-week supervised cardiac rehabilitation program, followed by three home-based sessions/week for 11 months. Liver fat (as intrahepatic lipid) and VAT were measured via magnetic resonance techniques. Data are mean change (95% CI).

RESULTS

HIIT and MICT significantly reduced VAT over 3 months (-350 [-548 to -153] cm³ vs. -456 [-634 to -278] cm³ ; time × group effect: P = 0.421), with further improvement over 12 months (-545 [-818 to -271] cm³ vs. -521 [-784 to -258] cm³ ; time × group effect: P = 0.577) and no differences between groups. Both groups improved liver fat over 3 months, with HIIT tending to show greater reduction than MICT (-2.8% [-4.0% to -1.6%] vs. -1.4% [-2.4% to -0.4%]; time × group effect: P = 0.077). After 12 months, improvements were maintained to a similar degree. Higher exercise intensity predicted liver fat reduction (β = -0.3 [-0.7 to 0.0]; P = 0.042).

CONCLUSIONS

HIIT and MICT reduced VAT over 3 and 12 months. For liver fat, HIIT tended to provide a slightly greater reduction compared with MICT. These findings support HIIT as a beneficial adjunct or alternative to MICT for reducing visceral and liver fat in patients with CAD.

High flow nasal oxygen after bariatric surgery (OXYBAR), prophylactic post-operative high flow nasal oxygen versus conventional oxygen therapy in obese patients undergoing bariatric surgery: study protocol for a randomised controlled pilot trial

BACKGROUND

The incidence of obesity is increasing worldwide. In selected individuals, bariatric surgery may offer a means of achieving long-term weight loss, improved health, and healthcare cost reduction. Physiological changes that occur because of obesity and general anaesthesia predispose to respiratory complications following bariatric surgery. The aim of this study is to determine whether post-operative high flow nasal oxygen therapy (HFNO2) improves respiratory function and reduces the incidence of post-operative pulmonary complications (PPCs) in comparison to conventional oxygen therapy in these patients.

METHOD

The OXYBAR study is a prospective, un-blinded, single centre, randomised, controlled pilot study. Patients with body mass index (BMI) > 30 kg/m2, undergoing laparoscopic bariatric surgery, will be randomised to receive either standard low flow oxygen therapy or HFNO2 in the post-operative period. The primary outcome measure is the change in end expiratory lung impedance (∆EELI) as measured by electrical impedance tomography (EIT). Secondary outcome measures include change in tidal volume (∆Vt), partial arterial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio, incidence of PPCs, hospital length of stay and measures of patient comfort.

DISCUSSION

We hypothesise that the post-operative administration of HFNO2 will increase EELI and therefore end expiratory lung volume (EELV) in obese patients. To our knowledge this is the first trial designed to assess the effects of HFNO2 on EELV in this population. We anticipate that data collected during this pilot study will inform a larger multicentre trial.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617000694314 . Registered on 15 May 2017.