Diagnosis of Acute Aortic Syndrome in the Emergency Department (DAShED) study: an observational cohort study of people attending the emergency department with symptoms consistent with acute aortic syndrome.

BACKGROUND: The diagnosis of acute aortic syndrome (AAS) is commonly delayed or missed in the ED. We describe characteristics of ED attendances with symptoms potentially associated with AAS, diagnostic performance of clinical decision tools (CDTs) and physicians and yield of CT aorta angiogram (CTA). METHODS: This was a multicentre observational cohort study of adults attending 27 UK EDs between 26 September 2022 and 30 November 2022, with potential AAS symptoms: chest, back or abdominal pain, syncope or symptoms related to malperfusion. Patients were preferably identified prospectively, but retrospective recruitment was also permitted. Anonymised, routinely collected patient data including components of CDTs, was abstracted. Clinicians treating prospectively identified patients were asked to record their perceived likelihood of AAS, prior to any confirmatory testing. Reference standard was radiological or operative confirmation of AAS. 30-day electronic patient record follow-up evaluated whether a subsequent diagnosis of AAS had been made and mortality. RESULTS: 5548 patients presented, with a median age of 55 years (IQR 37-72; n=5539). 14 (0.3%; n=5353) had confirmed AAS. 10/1046 (1.0%) patients in whom the ED clinician thought AAS was possible had AAS. 5/147 (3.4%) patients in whom AAS was considered the most likely diagnosis had AAS. 2/3319 (0.06%) patients in whom AAS was considered not possible did have AAS. 540 (10%; n=5446) patients underwent CT, of which 407 were CTA (7%). 30-day follow-up did not reveal any missed AAS diagnoses. AUROC (area under the receiver operating characteristic) curve for ED clinician AAS likelihood rating was 0.958 (95% CI 0.933 to 0.983, n=4006) and for individual CDTs were: Aortic Dissection Detection Risk Score (ADD-RS) 0.674 (95% CI 0.508 to 0.839, n=4989), AORTAs 0.689 (95% CI 0.527 to 0.852, n=5132), Canadian 0.818 (95% CI 0.686 to 0.951, n=5180) and Sheffield 0.628 (95% CI 0.467 to 0.788, n=5092). CONCLUSION: Only 0.3% of patients presenting with potential AAS symptoms had AAS but 7% underwent CTA. CDTs incorporating clinician gestalt appear to be most promising, but further prospective work is needed, including evaluation of the role of D-dimer. TRIAL REGISTRATION NUMBER: NCT05582967; NCT05582967.

A mixed method evaluation of a theory based intervention to reduce sedentary behaviour in contact centres- the stand up for health stepped wedge feasibility study.

INTRODUCTION: Contact centres have higher levels of sedentary behaviour than other office-based workplaces. Stand Up for Health (SUH) is a theory-based intervention developed using the 6SQuID framework to reduce sedentary behaviour in contact centre workers. The aim of this study was to test acceptability and feasibility of implementing SUH in UK contact centres. METHODS: The study was conducted in 2020-2022 (pre COVID and during lockdown) and used a stepped-wedge cluster randomised trial design including a process evaluation. The intervention included working with contact centre managers to develop and implement a customised action plan aligning with SUH's theory of change. Workplace sedentary time, measured using activPAL™ devices, was the primary outcome. Secondary outcomes included productivity, mental wellbeing, musculoskeletal health and physical activity. Empirical estimates of between-centre standard deviation and within-centre standard deviation of outcomes from pre-lockdown data were calculated to inform sample size calculations for future trials. The process evaluation adopted the RE-AIM framework to understand acceptability and feasibility of implementing the intervention. Interviews and focus groups were conducted with contact centre employees and managers, and activity preferences were collected using a questionnaire. RESULTS: A total of 11 contact centres participated: 155 employees from 6 centres in the pre-lockdown data collection, and 54 employees from 5 centres post-lockdown. Interviews and focus groups were conducted with 33 employees and managers, and 96 participants completed an intervention activity preference questionnaire. Overall, the intervention was perceived as acceptable and feasible to deliver. Most centres implemented several intervention activities aligned with SUH's theory of change and over 50% of staff participated in at least one activity (pre-lockdown period). Perceived benefits including reduced sedentary behaviour, increased physical activity, and improved staff morale and mood were reported by contact centre employees and managers. CONCLUSIONS: SUH demonstrates potential as an appealing and acceptable intervention, impacting several wellbeing outcomes. TRIAL REGISTRATION: The trial has been registered on the ISRCTNdatabase: http://www.isrctn.com/ISRCTN11580369.

AF and in-hospital mortality in COVID-19 patients.

Background: There are conflicting data on whether new-onset atrial fibrillation (AF) is independently associated with poor outcomes in COVID-19 patients. This study represents the largest dataset curated by manual chart review comparing clinical outcomes between patients with sinus rhythm, pre-existing AF, and new-onset AF. Objective: The primary aim of this study was to assess patient outcomes in COVID-19 patients with sinus rhythm, pre-existing AF, and new-onset AF. The secondary aim was to evaluate predictors of new-onset AF in patients with COVID-19 infection. Methods: This was a single-center retrospective study of patients with a confirmed diagnosis of COVID-19 admitted between March and September 2020. Patient demographic data, medical history, and clinical outcome data were manually collected. Adjusted comparisons were performed following propensity score matching between those with pre-existing or new-onset AF and those without AF. Results: The study population comprised of 1241 patients. A total of 94 (7.6%) patients had pre-existing AF and 42 (3.4%) patients developed new-onset AF. New-onset AF was associated with increased in-hospital mortality before (odds ratio [OR] 3.58, 95% confidence interval [CI] 1.78-7.06, P < .005) and after (OR 2.80, 95% CI 1.01-7.77, P < .005) propensity score matching compared with the no-AF group. However, pre-existing AF was not independently associated with in-hospital mortality compared with patients with no AF (postmatching OR: 1.13, 95% CI 0.57-2.21, P = .732). Conclusion: New-onset AF, but not pre-existing AF, was independently associated with elevated mortality in patients hospitalised with COVID-19. This observation highlights the need for careful monitoring of COVID-19 patients with new-onset AF. Further research is needed to explain the mechanistic relationship between new-onset AF and clinical outcomes in COVID-19 patients.

Longitudinal Metabolite Changes in Progressive Multiple Sclerosis: A Study of 3 Potential Neuroprotective Treatments.

BACKGROUND: 1 H-magnetic resonance spectroscopy (1 H-MRS) may provide a direct index for the testing of medicines for neuroprotection and drug mechanisms in multiple sclerosis (MS) through measures of total N-acetyl-aspartate (tNAA), total creatine (tCr), myo-inositol (mIns), total-choline (tCho), and glutamate + glutamine (Glx). Neurometabolites may be associated with clinical disability with evidence that baseline neuroaxonal integrity is associated with upper limb function and processing speed in secondary progressive MS (SPMS). PURPOSE: To assess the effect on neurometabolites from three candidate drugs after 96-weeks as seen by 1 H-MRS and their association with clinical disability in SPMS. STUDY-TYPE: Longitudinal. POPULATION: 108 participants with SPMS randomized to receive neuroprotective drugs amiloride [mean age 55.4 (SD 7.4), 61% female], fluoxetine [55.6 (6.6), 71%], riluzole [54.6 (6.3), 68%], or placebo [54.8 (7.9), 67%]. FIELD STRENGTH/SEQUENCE: 3-Tesla. Chemical-shift-imaging 2D-point-resolved-spectroscopy (PRESS), 3DT1. ASSESSMENT: Brain metabolites in normal appearing white matter (NAWM) and gray matter (GM), brain volume, lesion load, nine-hole peg test (9HPT), and paced auditory serial addition test were measured at baseline and at 96-weeks. STATISTICAL TESTS: Paired t-test was used to analyze metabolite changes in the placebo arm over 96-weeks. Metabolite differences between treatment arms and placebo; and associations between baseline metabolites and upper limb function/information processing speed at 96-weeks assessed using multiple linear regression models. P-value<0.05 was considered statistically significant. RESULTS: In the placebo arm, tCho increased in GM (mean difference = -0.32 IU) but decreased in NAWM (mean difference = 0.13 IU). Compared to placebo, in the fluoxetine arm, mIns/tCr was lower (ß = -0.21); in the riluzole arm, GM Glx (ß = -0.25) and Glx/tCr (ß = -0.29) were reduced. Baseline tNAA(ß = 0.22) and tNAA/tCr (ß = 0.23) in NAWM were associated with 9HPT scores at 96-weeks. DATA CONCLUSION: 1 H-MRS demonstrated altered membrane turnover over 96-weeks in the placebo group. It also distinguished changes in neuro-metabolites related to gliosis and glutaminergic transmission, due to fluoxetine and riluzole, respectively. Data show tNAA is a potential marker for upper limb function. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 4.

The unblinding of statisticians in clinical trials: commentary on Iflaifel et al., Trials 2023.

Recently, the Blinding of Trial Statisticians research team, Iflaifel and colleagues, have produced detailed guidance regarding the blinding or unblinding of statisticians in clinical trials, based on substantial mixed-methods work. I wish to comment on the research findings. In particular, I argue that open-label trials, non-drug trials, or non-inferiority trials should not be treated any differently from blinded superiority trials with regards to the risk of bias assessment. Prevention of bias should be the priority for definitive randomised controlled trials, regardless of the precise study design.

The importance of clinical importance when determining the target difference in sample size calculations.

Recently, it was argued that clinically important differences should play no role in sample size calculations. Instead, it was proposed that sample size calculations should focus on setting realistic estimates of treatment benefit. We disagree, and argue in this article that considering the importance of a target difference is necessary in the context of randomised controlled trials of effectiveness, particularly definitive phase III trials. Ignoring clinical importance could have serious ethical and practical consequences.

Asthma control and care among six public health clinic attenders in Malaysia: A cross-sectional study.

Background and Aims: Asthma is common in Malaysia but neglected. Achieving optimal asthma control and care is a challenge in the primary care setting. In this study, we aimed to identify the risk factors for poor asthma control and pattern of care among adults and children (5-17 years old) with asthma attending six public health clinics in Klang District, Malaysia. Methods: We conducted a cross-sectional study collecting patients' sociodemographic characteristics, asthma control, trigger factors, healthcare use, asthma treatment, and monitoring and use of asthma action plan. Descriptive statistics and stepwise logistic regression were used in data analysis. Results: A total of 1280 patients were recruited; 85.3% adults and 14.7% children aged 5-17 years old. Only 34.1% of adults had well-controlled asthma, 36.5% had partly controlled asthma, and 29.4% had uncontrolled asthma. In children, 54.3% had well-controlled asthma, 31.9% had partly controlled, and 13.8% had uncontrolled asthma. More than half had experienced one or more exacerbations in the last 1 year, with a mean of six exacerbations in adults and three in children. Main triggers for poor control in adults were haze (odds ratio [OR] 1.51; 95% confidence interval [CI] 1.13-2.01); cold food (OR 1.54; 95% CI 1.15-2.07), extreme emotion (OR 1.90; 95% CI 1.26-2.89); air-conditioning (OR 1.63; 95% CI 1.20-2.22); and physical activity (OR 2.85; 95% CI 2.13-3.82). In children, hot weather (OR 3.14; 95% CI 1.22-8.11), and allergic rhinitis (OR 2.57; 95% CI 1.13-5.82) contributed to poor control. The majority (81.7% of adults and 64.4% of children) were prescribed controller medications, but only 42.4% and 29.8% of the respective groups were compliant with the treatment. The importance of an asthma action plan was reported less emphasized in asthma education. Conclusion: Asthma control remains suboptimal. Several triggers, compliance to controller medications, and asthma action plan use require attention during asthma reviews for better asthma outcomes.

Statistical analysis plan for the motor neuron disease systematic multi-arm adaptive randomised trial (MND-SMART).

BACKGROUND: MND-SMART is a platform, multi-arm, multi-stage, multi-centre, randomised controlled trial recruiting people with motor neuron disease. Initially, the treatments memantine and trazodone will each be compared against placebo, but other investigational treatments will be introduced into the trial later. The co-primary outcomes are the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALS-FRS-R) functional outcome, which is assessed longitudinally, and overall survival. METHODS: Initially in MND-SMART, participants are randomised 1:1:1 via a minimisation algorithm to receive placebo or one of the two investigational treatments with up to 531 to be randomised in total. The comparisons between each research arm and placebo will be conducted in four stages, with the opportunity to cease further randomisations to poorly performing research arms at the end of stages 1 or 2. The final ALS-FRS-R analysis will be at the end of stage 3 and final survival analysis at the end of stage 4. The estimands for the co-primary outcomes are described in detail. The primary analysis of ALS-FRS-R at the end of stages 1 to 3 will involve fitting a normal linear mixed model to the data to calculate a mean difference in rate of ALS-FRS-R change between each research treatment and placebo. The pairwise type 1 error rate will be controlled, because each treatment comparison will generate its own distinct and separate interpretation. This publication is based on a formal statistical analysis plan document that was finalised and signed on 18 May 2022. DISCUSSION: In developing the statistical analysis plan, we had to carefully consider several issues such as multiple testing, estimand specification, interim analyses, and statistical analysis of the repeated measurements of ALS-FRS-R. This analysis plan attempts to balance multiple factors, including minimisation of bias, maximising power and precision, and deriving clinically interpretable summaries of treatment effects. TRIAL REGISTRATION: EudraCT Number, 2019-000099-41. Registered 2 October 2019, https://www.clinicaltrialsregister.eu/ctr-search/search?query=mnd-smart ClinicalTrials.gov, NCT04302870 . Registered 10 March 2020.

An Inhaled Galectin-3 Inhibitor in COVID-19 Pneumonitis: A Phase Ib/IIa Randomized Controlled Clinical Trial (DEFINE).

Rationale: High circulating galectin-3 is associated with poor outcomes in patients with coronavirus disease (COVID-19). We hypothesized that GB0139, a potent inhaled thiodigalactoside galectin-3 inhibitor with antiinflammatory and antifibrotic actions, would be safely and effectively delivered in COVID-19 pneumonitis. Objectives: Primary outcomes were safety and tolerability of inhaled GB0139 as an add-on therapy for patients hospitalized with COVID-19 pneumonitis. Methods: We present the findings of two arms of a phase Ib/IIa randomized controlled platform trial in hospitalized patients with confirmed COVID-19 pneumonitis. Patients received standard of care (SoC) or SoC plus 10 mg inhaled GB0139 twice daily for 48 hours, then once daily for up to 14 days or discharge. Measurements and Main Results: Data are reported from 41 patients, 20 of which were assigned randomly to receive GB0139. Primary outcomes: the GB0139 group experienced no treatment-related serious adverse events. Incidences of adverse events were similar between treatment arms (40 with GB0139 + SoC vs. 35 with SoC). Secondary outcomes: plasma GB0139 was measurable in all patients after inhaled exposure and demonstrated target engagement with decreased circulating galectin (overall treatment effect post-hoc analysis of covariance [ANCOVA] over days 2-7; P = 0.0099 vs. SoC). Plasma biomarkers associated with inflammation, fibrosis, coagulopathy, and major organ function were evaluated. Conclusions: In COVID-19 pneumonitis, inhaled GB0139 was well-tolerated and achieved clinically relevant plasma concentrations with target engagement. The data support larger clinical trials to determine clinical efficacy. Clinical trial registered with ClinicalTrials.gov (NCT04473053) and EudraCT (2020-002230-32).

Feasibility of supported self-management with a pictorial action plan to improve asthma control.

Supported self-management reduces asthma-related morbidity and mortality. This paper is on a feasibility study, and observing the change in clinical and cost outcomes of pictorial action plan use is part of assessing feasibility as it will help us decide on outcome measures for a fully powered RCT. We conducted a pre-post feasibility study among adults with physician-diagnosed asthma on inhaled corticosteroids at a public primary-care clinic in Malaysia. We adapted an existing pictorial asthma action plan. The primary outcome was asthma control, assessed at 1, 3 and 6 months. Secondary outcomes included reliever use, controller medication adherence, asthma exacerbations, emergency visits, hospitalisations, days lost from work/daily activities and action plan use. We estimated potential cost savings on asthma-related care following plan use. About 84% (n = 59/70) completed the 6-months follow-up. The proportion achieving good asthma control increased from 18 (30.4%) at baseline to 38 (64.4%) at 6-month follow-up. The proportion of at least one acute exacerbation (3 months: % difference -19.7; 95% CI -34.7 to -3.1; 6 months: % difference -20.3; 95% CI -5.8 to -3.2), one or more emergency visit (1 month: % difference -28.6; 95% CI -41.2 to -15.5; 3 months: % difference -18.0; 95% CI -32.2 to -3.0; 6 months: % difference -20.3; 95% CI -34.9 to -4.6), and one or more asthma admission (1 month: % difference -14.3; 95% CI -25.2 to -5.3; 6 months: % difference -11.9; 95% CI -23.2 to -1.8) improved over time. Estimated savings for the 59 patients at 6-months follow-up and for each patient over the 6 months were RM 15,866.22 (USD3755.36) and RM268.92 (USD63.65), respectively. Supported self-management with a pictorial asthma action plan was associated with an improvement in asthma control and potential cost savings in Malaysian primary-care patients.Trial registration number: ISRCTN87128530; prospectively registered: September 5, 2019, http://www.isrctn.com/ISRCTN87128530 .

Divergent confidence intervals among pre-specified analyses in the HiSTORIC stepped wedge trial: An exploratory post-hoc investigation.

BACKGROUND: The high-sensitivity cardiac troponin on presentation to rule out myocardial infarction (HiSTORIC) study was a stepped-wedge cluster randomised trial with long before-and-after periods, involving seven hospitals across Scotland. Results were divergent for the binary safety endpoint (type 1 or type 4b myocardial infarction or cardiac death) across certain pre-specified analyses, which warranted further investigation. In particular, the calendar-matched analysis produced an odds ratio in the opposite direction to the primary logistic mixed-effects model analysis. METHODS: Several post-hoc statistical models were fitted to each of the co-primary outcomes of length of hospital stay and safety events, which included adjusting for exposure time, incorporating splines, and fitting a random time effect. We improved control of patient characteristics over time by adjusting for multiple additional covariates using different methods: direct inclusion, regression adjustment for propensity score, and weighting. A data augmentation approach was also conducted aiming to reduce the effect of sparse data bias. Finally, the raw data was examined. RESULTS: The new statistical models confirmed the results of the pre-specified trial analysis. In particular, the observed divergence between the calendar-matched and other analyses remained, even after performing the covariate adjustment methods, and after using data augmentation. Divergence was particularly acute for the safety endpoint, which had an event rate of 0.36% overall. Examining the raw data was particularly helpful to assess the sensitivity of the results to small changes in event rates and identify patterns in the data. CONCLUSIONS: Our experience reveals the importance of conducting multiple pre-specified sensitivity analyses and examining the raw data, particularly for stepped wedge trials with low event rates or with a small number of sites. Before-and-after analytical approaches that adjust for differences in patient populations but avoid direct modelling of the time trend should be considered in future stepped wedge trials with similar designs.

Efficacy of Fluoxetine, Riluzole and Amiloride in treating neuropathic pain associated with secondary progressive multiple sclerosis. Pre-specified analysis of the MS-SMART double-blind randomised placebo-controlled trial.

BACKGROUND: Evidence-based treatment of pain in people with MS presents a major unmet need. OBJECTIVE: We aimed to establish if use of Fluoxetine, Riluzole or Amiloride improved neuropathic pain outcomes in comparison to placebo, in adults with secondary progressive MS participating in a trial of these putative neuroprotectants. METHODS: In pre-specified secondary analyses of the MS SMART phase-2b double-blind randomised controlled trial (NCT01910259), we analyzed reports of neuropathic pain, overall pain, and pain interference. Multivariate analyses included adjustment for baseline pain severity. Additionally, we explored associations of pain severity with clinical and MRI brain imaging variables. RESULTS: 445 Participants were recruited from 13 UK neuroscience centres. We found no statistically significant benefit of active intervention on any rating of neuropathic pain, or pain overall. Compared to placebo, adjusted mean difference in pain intensity was 0.38 (positive values favouring placebo, 95%CI -0.30 to 1.07, p = 0.27) for Amiloride; 0.52 (-0.17 to 1.22, p = 0.14) for Fluoxetine; and 0.40 (-0.30 to 1.10, p = 0.26) for Riluzole. Pain severity was positively correlated with depressive symptoms (Spearman correlation 0.19, 95%CI 0.10-0.28) and fatigue (Rho 0.30, 95%CI 0.20-0.39). CONCLUSION: Use of Fluoxetine, Riluzole or Amiloride was not associated with improvement in neuropathic pain symptoms, in comparison to placebo.

Randomised controlled trial of intravenous nafamostat mesylate in COVID pneumonitis: Phase 1b/2a experimental study to investigate safety, Pharmacokinetics and Pharmacodynamics.

BACKGROUND: Many repurposed drugs have progressed rapidly to Phase 2 and 3 trials in COVID19 without characterisation of Pharmacokinetics /Pharmacodynamics including safety data. One such drug is nafamostat mesylate. METHODS: We present the findings of a phase Ib/IIa open label, platform randomised controlled trial of intravenous nafamostat in hospitalised patients with confirmed COVID-19 pneumonitis. Patients were assigned randomly to standard of care (SoC), nafamostat or an alternative therapy. Nafamostat was administered as an intravenous infusion at a dose of 0.2 mg/kg/h for a maximum of seven days. The analysis population included those who received any dose of the trial drug and all patients randomised to SoC. The primary outcomes of our trial were the safety and tolerability of intravenous nafamostat as an add on therapy for patients hospitalised with COVID-19 pneumonitis. FINDINGS: Data is reported from 42 patients, 21 of which were randomly assigned to receive intravenous nafamostat. 86% of nafamostat-treated patients experienced at least one AE compared to 57% of the SoC group. The nafamostat group were significantly more likely to experience at least one AE (posterior mean odds ratio 5.17, 95% credible interval (CI) 1.10 - 26.05) and developed significantly higher plasma creatinine levels (posterior mean difference 10.57 micromol/L, 95% CI 2.43-18.92). An average longer hospital stay was observed in nafamostat patients, alongside a lower rate of oxygen free days (rate ratio 0.55-95% CI 0.31-0.99, respectively). There were no other statistically significant differences in endpoints between nafamostat and SoC. PK data demonstrated that intravenous nafamostat was rapidly broken down to inactive metabolites. We observed no significant anticoagulant effects in thromboelastometry. INTERPRETATION: In hospitalised patients with COVID-19, we did not observe evidence of anti-inflammatory, anticoagulant or antiviral activity with intravenous nafamostat, and there were additional adverse events. FUNDING: DEFINE was funded by LifeArc (an independent medical research charity) under the STOPCOVID award to the University of Edinburgh. We also thank the Oxford University COVID-19 Research Response Fund (BRD00230).

Multiple secondary outcome analyses: precise interpretation is important.

Analysis of multiple secondary outcomes in a clinical trial leads to an increased probability of at least one false significant result among all secondary outcomes studied. In this paper, we question the notion that that if no multiplicity adjustment has been applied to multiple secondary outcome analyses in a clinical trial, then they must necessarily be regarded as exploratory. Instead, we argue that if individual secondary outcome results are interpreted carefully and precisely, there is no need to downgrade our interpretation to exploratory. This is because the probability of a false significant result for each comparison, the per-comparison wise error rate, does not increase with multiple testing. Strong effects on secondary outcomes should always be taken seriously and must not be dismissed purely on the basis of multiplicity concerns.

Bayesian methods in palliative care research: cancer-induced bone pain.

OBJECTIVE: To show how a simple Bayesian analysis method can be used to improve the evidence base in patient populations where recruitment and retention are challenging. METHODS: A Bayesian conjugate analysis method was applied to binary data from the Thermal testing in Bone Pain (TiBoP) study: a prospective diagnostic accuracy/predictive study in patients with cancer-induced bone pain (CIBP). This study aimed to evaluate the clinical utility of a simple bedside tool to identify who was most likely to benefit from palliative radiotherapy (XRT) for CIBP. RESULTS: Recruitment and retention of patients were challenging due to the frail population, with only 27 patients available for the primary analysis. The Bayesian method allowed us to make use of prior work done in this area and combine it with the TiBoP data to maximise the informativeness of the results. Positive and negative predictive values were estimated with greater precision, and interpretation of results was facilitated by use of direct probability statements. In particular, there was only 7% probability that the true positive predictive value was above 80%. CONCLUSIONS: Several advantages of using Bayesian analysis are illustrated in this article. The Bayesian method allowed us to gain greater confidence in our interpretation of the results despite the small sample size by allowing us to incorporate data from a previous similar study. We suggest that this method is likely to be useful for the analysis of small diagnostic or predictive studies when prior information is available.

Clinical trials in amyotrophic lateral sclerosis: a systematic review and perspective.

Amyotrophic lateral sclerosis is a progressive and devastating neurodegenerative disease. Despite decades of clinical trials, effective disease-modifying drugs remain scarce. To understand the challenges of trial design and delivery, we performed a systematic review of Phase II, Phase II/III and Phase III amyotrophic lateral sclerosis clinical drug trials on trial registries and PubMed between 2008 and 2019. We identified 125 trials, investigating 76 drugs and recruiting more than 15 000 people with amyotrophic lateral sclerosis. About 90% of trials used traditional fixed designs. The limitations in understanding of disease biology, outcome measures, resources and barriers to trial participation in a rapidly progressive, disabling and heterogenous disease hindered timely and definitive evaluation of drugs in two-arm trials. Innovative trial designs, especially adaptive platform trials may offer significant efficiency gains to this end. We propose a flexible and scalable multi-arm, multi-stage trial platform where opportunities to participate in a clinical trial can become the default for people with amyotrophic lateral sclerosis.

Predictors for detecting chronic respiratory diseases in community surveys: A pilot cross-sectional survey in four South and South East Asian low- and middle-income countries.

BACKGROUND: Our previous scoping review revealed limitations and inconsistencies in population surveys of chronic respiratory disease. Informed by this review, we piloted a cross-sectional survey of adults in four South/South-East Asian low-and middle-income countries (LMICs) to assess survey feasibility and identify variables that predicted asthma or chronic obstructive pulmonary disease (COPD). METHODS: We administered relevant translations of the BOLD-1 questionnaire with additional questions from ECRHS-II, performed spirometry and arranged specialist clinical review for a sub-group to confirm the diagnosis. Using random sampling, we piloted a community-based survey at five sites in four LMICs and noted any practical barriers to conducting the survey. Three clinicians independently used information from questionnaires, spirometry and specialist reviews, and reached consensus on a clinical diagnosis. We used lasso regression to identify variables that predicted the clinical diagnoses and attempted to develop an algorithm for detecting asthma and COPD. RESULTS: Of 508 participants, 55.9% reported one or more chronic respiratory symptoms. The prevalence of asthma was 16.3%; COPD 4.5%; and 'other chronic respiratory disease' 3.0%. Based on consensus categorisation (n = 483 complete records), "Wheezing in last 12 months" and "Waking up with a feeling of tightness" were the strongest predictors for asthma. For COPD, age and spirometry results were the strongest predictors. Practical challenges included logistics (participant recruitment; researcher safety); misinterpretation of questions due to local dialects; and assuring quality spirometry in the field. CONCLUSION: Detecting asthma in population surveys relies on symptoms and history. In contrast, spirometry and age were the best predictors of COPD. Logistical, language and spirometry-related challenges need to be addressed.

Robust and flexible inference for the covariate-specific receiver operating characteristic curve.

Diagnostic tests are of critical importance in health care and medical research. Motivated by the impact that atypical and outlying test outcomes might have on the assessment of the discriminatory ability of a diagnostic test, we develop a robust and flexible model for conducting inference about the covariate-specific receiver operating characteristic (ROC) curve that safeguards against outlying test results while also accommodating for possible nonlinear effects of the covariates. Specifically, we postulate a location-scale regression model for the test outcomes in both the diseased and nondiseased populations, combining additive regression B-splines and M-estimation for the regression function, while the distribution of the error term is estimated via a weighted empirical distribution function of the standardized residuals. The results of the simulation study show that our approach successfully recovers the true covariate-specific area under the ROC curve on a variety of conceivable test outcomes contamination scenarios. Our method is applied to a dataset derived from a prostate cancer study where we seek to assess the ability of the Prostate Health Index to discriminate between men with and without Gleason 7 or above prostate cancer, and if and how such discriminatory capacity changes with age.

High-Sensitivity Cardiac Troponin on Presentation to Rule Out Myocardial Infarction: A Stepped-Wedge Cluster Randomized Controlled Trial.

BACKGROUND: High-sensitivity cardiac troponin assays enable myocardial infarction to be ruled out earlier, but the safety and efficacy of this approach is uncertain. We investigated whether an early rule-out pathway is safe and effective for patients with suspected acute coronary syndrome. METHODS: We performed a stepped-wedge cluster randomized controlled trial in the emergency departments of 7 acute care hospitals in Scotland. Consecutive patients presenting with suspected acute coronary syndrome between December 2014 and December 2016 were included. Sites were randomized to implement an early rule-out pathway where myocardial infarction was excluded if high-sensitivity cardiac troponin I concentrations were <5 ng/L at presentation. During a previous validation phase, myocardial infarction was ruled out when troponin concentrations were <99th percentile at 6 to 12 hours after symptom onset. The coprimary outcome was length of stay (efficacy) and myocardial infarction or cardiac death after discharge at 30 days (safety). Patients were followed for 1 year to evaluate safety and other secondary outcomes. RESULTS: We enrolled 31 492 patients (59±17 years of age [mean±SD]; 45% women) with troponin concentrations <99th percentile at presentation. Length of stay was reduced from 10.1±4.1 to 6.8±3.9 hours (adjusted geometric mean ratio, 0.78 [95% CI, 0.73-0.83]; P<0.001) after implementation and the proportion of patients discharged increased from 50% to 71% (adjusted odds ratio, 1.59 [95% CI, 1.45-1.75]). Noninferiority was not demonstrated for the 30-day safety outcome (upper limit of 1-sided 95% CI for adjusted risk difference, 0.70% [noninferiority margin 0.50%]; P=0.068), but the observed differences favored the early rule-out pathway (0.4% [57/14 700] versus 0.3% [56/16 792]). At 1 year, the safety outcome occurred in 2.7% (396/14 700) and 1.8% (307/16 792) of patients before and after implementation (adjusted odds ratio, 1.02 [95% CI, 0.74-1.40]; P=0.894), and there were no differences in hospital reattendance or all-cause mortality. CONCLUSIONS: Implementation of an early rule-out pathway for myocardial infarction reduced length of stay and hospital admission. Although noninferiority for the safety outcome was not demonstrated at 30 days, there was no increase in cardiac events at 1 year. Adoption of this pathway would have major benefits for patients and health care providers. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03005158.