Selection bias in clinical stroke trials depending on ability to consent

Improving the inclusion of an under-served group in trials: development and implementation of the INCLUDE Impaired Capacity to Consent Framework

BACKGROUND

For the potential benefits of trials to reach all that they should, trials must be designed to ensure that those taking part reflect the population who will receive the intervention. However, adults with impaired capacity to consent are frequently excluded from trials - partly because researchers are unfamiliar with the legal and ethical frameworks and lack the necessary methodological expertise. Researchers identified a need for guidance on designing more inclusive trials. Building on the NIHR INCLUDE initiative, we developed the INCLUDE Impaired Capacity to Consent Framework to help researchers design inclusive trials.

METHODS

The framework was developed over five phases: (1) establishing the scope and content of the framework and adapting the INCLUDE Ethnicity Framework for this population; (2) scoping the relevance of the framework to different populations and piloting in a range of trials; (3) consulting people living with impairing conditions and carers to explore their views about the framework and identify missing content areas; (4) refining the framework; and (5) the development of an implementation toolkit of resources to support researchers using the framework.

RESULTS

The framework has two parts: a set of four key questions to help researchers identify who should be included in their trial, and a series of worksheets covering intervention design, recruitment and consent processes, data collection and analysis, and public involvement and dissemination. It is supported by a summary of the ethical and legal frameworks and a website of resources on capacity and consent. Implementation resources include infographics and animations, a library of completed frameworks, and facilitated workshops for researchers. The framework and toolkit were launched at a webinar (November 2022), with polling demonstrating an increase in attendees' awareness about research involving adults lacking capacity. A post-webinar survey found that stakeholders viewed the framework and toolkit as valuable tools to facilitate greater inclusion of this under-served population in trials. The framework is available online: https://www.capacityconsentresearch.com/include-impaired-capacity-to-consent-framework.html .

CONCLUSIONS

The INCLUDE Impaired Capacity to Consent Framework and implementation toolkit can support researchers to design more inclusive trials and other types of research studies. Further engagement, including with funders who are key to ensuring uptake, and evaluation is needed.

A scoping review of the use of visual tools and adapted easy-read approaches in Quality-of-Life instruments for adults

PURPOSE

Self-Reporting using traditional text-based Quality-of-Life (QoL) instruments can be difficult for people living with sensory impairments, communication challenges or changes to their cognitive capacity. Adapted communication techniques, such as Easy-Read techniques, or use of pictures could remove barriers to participation for a wide range of people. This review aimed to identify published studies reporting adapted communication approaches for measuring QoL, the methodology used in their development and validation among adult populations.

METHODS

A scoping review of the literature using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews checklist was undertaken.

RESULTS

The initial search strategy identified 13,275 articles for screening, with 264 articles identified for full text review. Of these 243 articles were excluded resulting in 21 studies for inclusion. The majority focused on the development of an instrument (12 studies) or a combination of development with some aspect of validation or psychometric testing (7 studies). Nineteen different instruments were identified by the review, thirteen were developed from previously developed generic or condition-specific quality of life instruments, predominantly aphasia (7 studies) and disability (4 studies). Most modified instruments included adaptations to both the original questions, as well as the response categories.

CONCLUSIONS

Studies identified in this scoping review demonstrate that several methods have been successfully applied e.g. with people living with aphasia post-stroke and people living with a disability, which potentially could be adapted for application with more diverse populations. A cohesive and interdisciplinary approach to the development and validation of communication accessible versions of QOL instruments, is needed to support widespread application, thereby reducing reliance on proxy assessors and promoting self-assessment of QOL across multiple consumer groups and sectors.

The effect of repeated remote ischemic postconditioning after an ischemic stroke (REPOST): A randomized controlled trial

BACKGROUND AND AIMS

A potential strategy to treat ischemic stroke may be the application of repeated remote ischemic postconditioning (rIPostC). This consists of several cycles of brief periods of limb ischemia followed by reperfusion, which can be applied by inflating a simple blood pressure cuff and subsequently could result in neuroprotection after stroke.

METHODS

Adult patients admitted with an ischemic stroke in the past 24 h were randomized 1:1 to repeated rIPostC or sham-conditioning. Repeated rIPostC was performed by inflating a blood pressure cuff around the upper arm (4 × 5 min at 200 mm Hg), which was repeated twice daily during hospitalization with a maximum of 4 days. Primary outcome was infarct size after 4 days or at discharge. Secondary outcomes included the modified Rankin Scale (mRS)-score after 12 weeks and the National Institutes of Health Stroke Scale (NIHSS) at discharge.

RESULTS

The trial was preliminarily stopped after we included 88 of the scheduled 180 patients (average age: 70 years, 68% male) into rIPostC (n = 40) and sham-conditioning (n = 48). Median infarct volume was 2.19 mL in rIPostC group and 5.90 mL in sham-conditioning, which was not significantly different between the two groups (median difference: 3.71; 95% CI: -0.56 to 6.09; p = 0.31). We found no significant shift in the mRS score distribution between groups. The adjusted common odds ratio was 2.09 (95% CI: 0.88-5.00). We found no significant difference in the NIHSS score between groups (median difference: 1.00; 95% CI: -0.99 to 1.40; p = 0.51).

CONCLUSION

This study found no significant improvement in infarct size or clinical outcome in patients with an acute ischemic stroke who were treated with repeated remote ischemic postconditioning. However, due to a lower-than-expected inclusion rate, no definitive conclusions about the effectiveness of rIPostC can be drawn.

Intracerebral haemorrhage expansion: definitions, predictors, and prevention

Haematoma expansion affects a fifth of patients within 24 h of the onset of acute intracerebral haemorrhage and is associated with death and disability, which makes it an appealing therapeutic target. The time in which active intervention can be done is short as expansion occurs mostly within the first 3 h after onset. Baseline haemorrhage volume, antithrombotic treatment, and CT angiography spot signs are each associated with increased risk of haematoma expansion. Non-contrast CT features are promising predictors of haematoma expansion, but their potential contribution to current models is under investigation. Blood pressure lowering and haemostatic treatment minimise haematoma expansion but have not led to improved functional outcomes in randomised clinical trials. Ultra-early enrolment and selection of participants on the basis of non-contrast CT imaging markers could focus future clinical trials to show clinical benefit in people at high risk of expansion or investigate heterogeneity of treatment effects in clinical trials with broad inclusion criteria.

Cardiac dysfunction and high-sensitive C-reactive protein are associated with troponin T elevation in ischemic stroke: insights from the SICFAIL study

BACKGROUND

Troponin elevation is common in ischemic stroke (IS) patients. The pathomechanisms involved are incompletely understood and comprise coronary and non-coronary causes, e.g. autonomic dysfunction. We investigated determinants of troponin elevation in acute IS patients including markers of autonomic dysfunction, assessed by heart rate variability (HRV) time domain variables.

METHODS

Data were collected within the Stroke Induced Cardiac FAILure (SICFAIL) cohort study. IS patients admitted to the Department of Neurology, Würzburg University Hospital, underwent baseline investigation including cardiac history, physical examination, echocardiography, and blood sampling. Four HRV time domain variables were calculated in patients undergoing electrocardiographic Holter monitoring. Multivariable logistic regression with corresponding odds ratios (OR) and 95% confidence intervals (CI) was used to investigate the determinants of high-sensitive troponin T (hs-TnT) levels ≥14 ng/L.

RESULTS

We report results from 543 IS patients recruited between 01/2014-02/2017. Of those, 203 (37%) had hs-TnT ≥14 ng/L, which was independently associated with older age (OR per year 1.05; 95% CI 1.02-1.08), male sex (OR 2.65; 95% CI 1.54-4.58), decreasing estimated glomerular filtration rate (OR per 10 mL/min/1.73 m² 0.71; 95% CI 0.61-0.84), systolic dysfunction (OR 2.79; 95% CI 1.22-6.37), diastolic dysfunction (OR 2.29; 95% CI 1.29-4.02), atrial fibrillation (OR 2.30; 95% CI 1.25-4.23), and increasing levels of C-reactive protein (OR 1.48 per log unit; 95% CI 1.22-1.79). We did not identify an independent association of troponin elevation with the investigated HRV variables.

CONCLUSION

Cardiac dysfunction and elevated C-reactive protein, but not a reduced HRV as surrogate of autonomic dysfunction, were associated with increased hs-TnT levels in IS patients independent of established cardiovascular risk factors. Registration-URL: https://www.drks.de/drks_web/; Unique identifier: DRKS00011615.

Advancing brain network models to reconcile functional neuroimaging and clinical research

Functional magnetic resonance imaging (fMRI) captures information on brain function beyond the anatomical alterations that are traditionally visually examined by neuroradiologists. However, the fMRI signals are complex in addition to being noisy, so fMRI still faces limitations for clinical applications. Here we review methods that have been proposed as potential solutions so far, namely statistical, biophysical and decoding models, with their strengths and weaknesses. We especially evaluate the ability of these models to directly predict clinical variables from their parameters (predictability) and to extract clinically relevant information regarding biological mechanisms and relevant features for classification and prediction (interpretability). We then provide guidelines for useful applications and pitfalls of such fMRI-based models in a clinical research context, looking beyond the current state of the art. In particular, we argue that the clinical relevance of fMRI calls for a new generation of models for fMRI data, which combine the strengths of both biophysical and decoding models. This leads to reliable and biologically meaningful model parameters, which thus fulfills the need for simultaneous interpretability and predictability. In our view, this synergy is fundamental for the discovery of new pharmacological and interventional targets, as well as the use of models as biomarkers in neurology and psychiatry.

Towards the consistent inclusion of people with aphasia in stroke research irrespective of discipline

People with aphasia have been systematically excluded from stroke research or included without the necessary modifications, threatening external study validity. In this paper, we propose that 1) the inclusion of people with aphasia should be considered as standard in stroke research irrespective of discipline and that 2) modifications should be made to stroke research procedures to support people with aphasia to achieve meaningful and valid inclusion. We argue that outright exclusion of this heterogenous population from stroke research based purely on a diagnosis of aphasia is rarely required and present a rationale for deliberate inclusion of people with aphasia in stroke research. The purpose of this paper is fourfold; 1) to highlight the issue and implications of excluding people with aphasia from stroke research; 2) to acknowledge the current barriers to including people with aphasia in stroke research; 3) to provide stroke researchers with methods to enable inclusion, including recommendations, resources, and guidance; and 4) to consider research needed to develop aphasia inclusive practices in stroke research.

Development of a patient-oriented navigation model for patients with lung cancer and stroke in Germany

Background

The concept of patient navigation was first established in the USA to support vulnerable patient groups in receiving timely and comprehensive access to cancer care. It has recently gained increasing interest in Germany to support patients with chronic diseases in a fragmented healthcare system. The aim of this paper is to present the development of such a model adapted to the German context based on the results of mixed-methods studies investigating the need for and barriers to patient-oriented care.

Methods

In a process adapted from Delphi rounds, we conducted regular structured workshops with investigators of the project to discuss results of their studies and identify content and structure of the model based on the data. Workshop discussions were structured along seven core components of a navigation model including target patient groups, navigator tasks, occupational background and education of navigators, and patient-navigator interaction mode.

Results

Using an approach based on empirical data of current care practices with special focus on patients’ perspectives, we developed a patient-oriented navigation model for patients who have experienced stroke and lung cancer in the German healthcare context. Patients without personal social support were viewed as struggling most with the healthcare system, as well as multimorbid and elderly patients. Navigators should serve as a longer-term contact person with a flexible contact mode and timing based on the individual situation and preferences of patients. Navigator tasks include the provision of administrative and organizational support as well as referral and guidance to available resources and beneficial health programs with special forms of knowledge. Implementation of the navigator should be flexibly located to ensure a reliable outreach to vulnerable patients for first contact in settings like specialized in-patient and out-patient settings, while navigation itself focuses on care coordination in the out-patient setting.

Conclusion

Flexibility of navigator tasks needed to be a core characteristic of a navigation model to be perceived as supportive from patients’ perspectives. In a subsequent feasibility study, an intervention based on the model will be evaluated according to its acceptance, demand, and practicality.

Challenges Encountered in Surgical Traumatic Brain Injury Research: A Need for Methodological Improvement of Future Studies

BACKGROUND

Investigating neurosurgical interventions for traumatic brain injury (TBI) involves complex methodological and practical challenges. In the present report, we have provided an overview of the current state of neurosurgical TBI research and discussed the key challenges and possible solutions.

METHODS

The content of our report was based on an extensive literature review and personal knowledge and expert opinions of senior neurosurgeon researchers and epidemiologists.

RESULTS

Current best practice research strategies include randomized controlled trials (RCTs) and comparative effectiveness research. The performance of RCTs has been complicated by the heterogeneity of TBI patient populations with the associated sample size requirements, the traditional eminence-based neurosurgical culture, inadequate research budgets, and the often acutely life-threatening setting of severe TBI. Statistical corrections can mitigate the effects of heterogeneity, and increasing awareness of clinical equipoise and informed consent alternatives can improve trial efficiency. The substantial confounding by indication, which limits the interpretability of observational research, can be circumvented by using an instrumental variable analysis. Traditional TBI outcome measures remain relevant but do not adequately capture the subtleties of well-being, suggesting a need for multidimensional approaches to outcome assessments.

CONCLUSIONS

In settings in which traditional RCTs are difficult to conduct and substantial confounding by indication can be present, observational studies using an instrumental variable analysis and "pragmatic" RCTs are promising alternatives. Embedding TBI research into standard clinical practice should be more frequently considered but will require fundamental modifications to the current health care system. Finally, multimodality outcome assessment will be key to improving future surgical and nonsurgical TBI research.

Guideline adherence in speech and language therapy in stroke aftercare. A health insurance claims data analysis

Background

Impairments to comprehension and production of speech (aphasia, dysarthria) and swallowing disorders (dysphagia) are common sequelae of stroke, reducing patients’ quality of life and social participation. Treatment oriented on evidence-based guidelines seems likely to improve outcomes. Currently, little is known about guideline adherence in stroke aftercare for the above-mentioned sequelae. This study aims to analyse guideline adherence in the treatment of aphasia, dysarthria and dysphagia after stroke, based on suitable test parameters, and to determine factors that influence the implementation of recommended therapies.

Methods

Six test parameters were defined, based on systematic study of guidelines for the treatment of speech impairments and swallowing disorders (e.g. comprehensive diagnostics, early initiation and continuity). Guideline adherence in treatment was tested using claims data from four statutory health insurance companies. Multivariate logistic and linear regression analyses were performed in order to test the outcomes.

Results

4,486 stroke patients who were diagnosed with specific disorders or received speech therapy were included in the study. The median age was 78 years; the proportion of women was 55.9%. Within the first year after the stroke, 90.3% of patients were diagnosed with speech impairments and swallowing disorders. Overall, 44.1% of patients received outpatient speech and language therapy aftercare. Women were less frequently diagnosed with specific disorders (OR 0.70 [95%CI:0.55/0.88], p = 0.003) and less frequently received longer therapy sessions (OR 0.64 [95%CI:0.43/0.94], p = 0.022). Older age and longer hospitalization duration increased the likelihood of guideline recommendations being implemented and of earlier initiation of stroke aftercare measures.

Conclusions

Our observations indicate deficits in the implementation of guideline recommendations in stroke aftercare. At the same time, they underscore the need for regular monitoring of implementation measures in stroke aftercare to address group-based disparities in care.

Translational Block in Stroke: A Constructive and "Out-of-the-Box" Reappraisal

Why can we still not translate preclinical research to clinical treatments for acute strokes? Despite > 1000 successful preclinical studies, drugs, and concepts for acute stroke, only two have reached clinical translation. This is the translational block. Yet, we continue to routinely model strokes using almost the same concepts we have used for over 30 years. Methodological improvements and criteria from the last decade have shed some light but have not solved the problem. In this conceptual analysis, we review the current status and reappraise it by thinking "out-of-the-box" and over the edges. As such, we query why other scientific fields have also faced the same translational failures, to find common denominators. In parallel, we query how migraine, multiple sclerosis, and hypothermia in hypoxic encephalopathy have achieved significant translation successes. Should we view ischemic stroke as a "chronic, relapsing, vascular" disease, then secondary prevention strategies are also a successful translation. Finally, based on the lessons learned, we propose how stroke should be modeled, and how preclinical and clinical scientists, editors, grant reviewers, and industry should reconsider their routine way of conducting research. Translational success for stroke treatments may eventually require a bold change with solutions that are outside of the box.

Prevalence and correlates of post-traumatic stress disorder after ischaemic stroke

Although most often considered a consequence of traumatic event, post-traumatic stress disorder (PTSD) also occurs after illness. The aim of this study was to establish prevalence of PTSD in patients with ischaemic stroke (IS) and its correlation to lesion location, degree of disability, age, gender and marital status. The study included 85 patients with IS. PTSD was diagnosed using a modified version of the PTSD Checklist Specific for a stressor (PCL-S). Depression and anxiety were assessed using Hospital Anxiety and Depression Scale (HADS). We defined stroke localisation as right cerebral hemisphere, left cerebral hemisphere, brainstem and cerebellum. Stroke severity was measured using the modified Rankin scale (mRS). Demographic information including age, gender and marital status was collected from medical history. Of the 85 patients with IS, 11 (12.9%) fulfilled PCL-S criteria for PTSD. We found a positive correlation between PTSD and higher degree of disability, P < 0.001. Patients with PTSD had lesions more frequently localised in the right cerebral hemisphere and the brainstem. We found no statistically significant correlation of PTSD with age, gender and marital status. Our results show that a significant number of IS patients develop PTSD after IS. Determining correlates of post-stroke PTSD can help to identify those at higher risk for its development. If proven by additional large sample studies, more patients can benefit from screening for the PTSD symptoms.

Informed consent procedures for emergency interventional research in patients with traumatic brain injury and ischaemic stroke

Health-care professionals and researchers have a legal and ethical responsibility to inform patients before carrying out diagnostic tests or treatment interventions as part of a clinical study. Interventional research in emergency situations can involve patients with some degree of acute cognitive impairment, as is regularly the case in traumatic brain injury and ischaemic stroke. These patients or their proxies are often unable to provide informed consent within narrow therapeutic time windows. International regulations and national laws are criticised for being inconclusive or restrictive in providing solutions. Currently accepted consent alternatives are deferred consent, exception from consent, or waiver of consent. However, these alternatives appear under-utilised despite being ethically permissible, socially acceptable, and regulatorily compliant. We anticipate that, when the requirements for medical urgency are properly balanced with legal and ethical conduct, the increased use of these alternatives has the potential to improve the efficiency and quality of future emergency interventional studies in patients with an inability to provide informed consent.

Burden of Premature Atrial Complexes and Risk of Recurrent Stroke and Death in Patients with Mild to Moderate Ischemic Stroke

BACKGROUND

Premature atrial complexes (PACs) meet increased attention as a potential intermediary between sinus rhythm and atrial fibrillation (AF). Patients with even high numbers of PACs do not fulfill current guidelines for oral anticoagulation treatment though an associated stroke risk is suspected.

OBJECTIVE

We aimed to determine whether a high number of PACs or runs of AF less than 30 seconds in 2-day continuous electrocardiogram (ECG) recording was associated with risk of recurrent ischemic stroke/transient ischemic attack (TIA) or death in a large cohort of patients with acute ischemic stroke or TIA and no prior AF.

METHODS

We performed 48 hours continuous ECG recording within 1 week after ischemic stroke/TIA. PACs were reported as mean number of PACs per hour. Patients were followed in Danish Stroke Registry, Danish Civil Registration System, and Danish National Patient Registry. Cox Regression analysis was used to calculate hazard ratios.

RESULTS

We included 1507 patients with TIA (40%) or ischemic stroke (60%), of which 98.7% had mild to moderate strokes. Mean age was 72.9 (7.8) years, 43.4% were females. Follow-up was 2.3 (1.3) years. Hazard ratio for recurrent stroke/TIA or death did not differ between quartiles of PAC burden, nor did any of the 2 components of this composite endpoint. Nonsustained AF less than 30 seconds was not associated with higher risk of recurrent stroke/TIA or death.

CONCLUSIONS

In a large cohort of patients with recent ischemic stroke or TIA, burden of PACs or nonsustained AF less than 30 seconds were not associated to higher risk of recurrent stroke/TIA or death.

Neurological Deficits in Stroke Patients that May Impede the Capacity to Provide Informed Consent for Endovascular Treatment Trials

BACKGROUND

We assessed the occurrence of neurological deficits that may impede the capacity to provide consent for trial participation in patients with an acute stroke, who are eligible for endovascular treatment (EVT).

METHODS

We used data from the Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry, a prospective observational cohort study. We included 1526 patients with an anterior large vessel occlusion, undergoing EVT between March 2014 and June 2016. We based our assessment of decision-making capacity for trial participation on neurological symptoms influencing conditions concerning informed consent as stated in the declaration of Helsinki. We formulated a strict and a mild capacity assessment rule, using 2 different cut points in item scores on the National Institutes of Health Stroke Scale (NIHSS).

RESULTS

Applying the strict and mild rule, respectively 1469 (96%) and 1220 (80%) patients deemed not capable of decision-making for trial participation on admission, and 1077 (79%) and 825 (60%) patients at 24-48 hours after admission. Highest frequencies of predefined scores suggesting incapacity based on the strict rule were on the NIHSS items "Level of Consciousness Questions" (59%), "Best Gaze" (68%), and "Best Language" (58%). Patients who were considered incapable were older (median 71 versus 66 years, P = .043), had higher NIHSS scores (median 16 versus 8, P < .001), and had more often left hemisphere strokes (55% versus 28%, P < .001) than patients who were presumably capable.

CONCLUSIONS

In the majority of patients with an anterior circulation stroke who are eligible for EVT, neurological deficits are present that may impede the capacity to provide informed consent for trial participation.