Language and cognitive outcomes after childhood stroke: Theoretical implications for hemispheric specialization

Predictors of neurocognitive outcome in pediatric ischemic and hemorrhagic stroke

This clinical study examined the impact of eight predictors (age at stroke, stroke type, lesion size, lesion location, time since stroke, neurologic severity, seizures post-stroke, and socioeconomic status) on neurocognitive functioning following pediatric stroke. Youth with a history of pediatric ischemic or hemorrhagic stroke (n = 92, ages six to 25) underwent neuropsychological testing and caregivers completed parent-report questionnaires. Hospital records were accessed for medical history. Spline regressions, likelihood ratios, one-way analysis of variance, Welch's t-tests, and simple linear regressions examined associations between predictors and neuropsychological outcome measures. Large lesions and lower socioeconomic status were associated with worse neurocognitive outcomes across most neurocognitive domains. Ischemic stroke was associated with worse outcome in attention and executive functioning compared to hemorrhagic stroke. Participants with seizures had more severe executive functioning impairments than participants without seizures. Youth with cortical-subcortical lesions scored lower on a few measures than youth with cortical or subcortical lesions. Neurologic severity predicted scores on few measures. No differences were found based on time since stroke, lesion laterality, or supra- versus infratentorial lesion. In conclusion, lesion size and socioeconomic status predict neurocognitive outcome following pediatric stroke. An improved understanding of predictors is valuable to clinicians who have responsibilities related to neuropsychological assessment and treatments for this population. Findings should inform clinical practice through enhanced appraisals of prognosis and the use of a biopsychosocial approach when conceptualizing neurocognitive outcome and setting up support services aimed at fostering optimal development for youth with stroke.

Against cortical reorganisation

Neurological insults, such as congenital blindness, deafness, amputation, and stroke, often result in surprising and impressive behavioural changes. Cortical reorganisation, which refers to preserved brain tissue taking on a new functional role, is often invoked to account for these behavioural changes. Here, we revisit many of the classical animal and patient cortical remapping studies that spawned this notion of reorganisation. We highlight empirical, methodological, and conceptual problems that call this notion into doubt. We argue that appeal to the idea of reorganisation is attributable in part to the way that cortical maps are empirically derived. Specifically, cortical maps are often defined based on oversimplified assumptions of 'winner-takes-all', which in turn leads to an erroneous interpretation of what it means when these maps appear to change. Conceptually, remapping is interpreted as a circuit receiving novel input and processing it in a way unrelated to its original function. This implies that neurons are either pluripotent enough to change what they are tuned to or that a circuit can change what it computes. Instead of reorganisation, we argue that remapping is more likely to occur due to potentiation of pre-existing architecture that already has the requisite representational and computational capacity pre-injury. This architecture can be facilitated via Hebbian and homeostatic plasticity mechanisms. Crucially, our revised framework proposes that opportunities for functional change are constrained throughout the lifespan by the underlying structural 'blueprint'. At no period, including early in development, does the cortex offer structural opportunities for functional pluripotency. We conclude that reorganisation as a distinct form of cortical plasticity, ubiquitously evoked with words such as 'take-over'' and 'rewiring', does not exist.

Autism Spectrum Disorder in Children With Perinatal Ischemic Stroke Varies by Stroke Type

Background and Objectives: Perinatal stroke leads to significant morbidity over a child's lifetime, including diagnosis of various neurodevelopmental disorders. Specific studies examining the prevalence of autism spectrum disorder in children with perinatal stroke are scarce. Following the clinical observation of autism spectrum disorder in a pediatric referral stroke center, we evaluated the rate of autism spectrum disorder diagnosis after perinatal ischemic stroke, including analysis by subtypes of perinatal ischemic stroke. Methods: We retrospectively examined all children diagnosed with perinatal ischemic stroke, who were ≥18 months old at the time of last follow-up at a single institution from 2008 through 2021. We classified patients as having autism spectrum disorder if they were diagnosed by a neurologist, neuropsychologist, clinical psychologist, or developmental pediatrician. Multivariable logistic regression was performed to examine the association between ischemic stroke subtype and autism spectrum disorder. Results: Among 260 children with perinatal stroke, 19 children (7.3%) also had autism spectrum disorder. Children with perinatal venous stroke had 3-fold higher odds of autism spectrum disorder compared to those with perinatal arterial ischemic stroke (adjusted odds ratio: 3.01, 95% confidence interval: 1.07-8.47). Conclusion: In our perinatal ischemic stroke population, children with venous stroke had higher odds of autism spectrum disorder compared to those with arterial ischemic stroke alone. Prospective studies are needed to further investigate the role of perinatal stroke in autism spectrum disorder development.

Implications of age at lesion onset for neuropsychological outcomes: A systematic review focusing on focal brain lesions

Theories of the relation between age at lesion onset and outcomes posit different views of the young brain: resilient and plastic (i.e., the so-called "Kennard Principle"), or vulnerable (i.e., the Early Vulnerability Hypothesis). There is support for both perspectives in previous research and questions about the "best" or "worst" times to sustain brain injury remain. Here, we present a systematic review investigating the influence of age at focal brain lesion onset on cognitive functioning. This systematic review identifies and qualitatively synthesizes empirical studies from 1985 to 2021 that investigated age at lesion onset as a variable of interest associated with neuropsychological outcomes. A total of 45 studies were identified from PubMed, PsycINFO, and CINAHL databases. Almost all studies indicated that brain injury earlier in the developmental period predicts worse cognitive outcomes when compared to onset either later in the developmental period or in adulthood. More specifically, the overwhelming majority of studies support an "earlier is worse" model for domains of intellect, processing speed, attention and working memory, visuospatial and perceptual skills, and learning and memory. Relatively more variability in outcomes exists for domains of language and executive functioning. Outcomes for all domains are influenced by various other age and injury variables (e.g., lesion size, lesion laterality, chronicity, a history of epilepsy). Continued interdisciplinary understanding and communication about the influence of age at lesion onset on neuropsychological outcomes will aid in promoting the best possible outcomes for patients.

Heart rate monitoring to detect acute pain in non-verbal patients: a study protocol for a randomized controlled clinical trial

BACKGROUND

Autism entails reduced communicative abilities. Approximately 30% of individuals with autism have intellectual disability (ID). Some people with autism and ID are virtually non-communicative and unable to notify their caregivers when they are in pain. In a pilot study, we showed that heart rate (HR) monitoring may identify painful situations in this patient group, as HR increases in acutely painful situations.

OBJECTIVES

This study aims to generate knowledge to reduce the number of painful episodes in non-communicative patients' everyday lives. We will 1) assess the effectiveness of HR as a tool for identifying potentially painful care procedures, 2) test the effect of HR-informed changes in potentially painful care procedures on biomarkers of pain, and 3) assess how six weeks of communication through HR affects the quality of communication between patient and caregiver.

METHODS

We will recruit 38 non-communicative patients with autism and ID residing in care homes.

ASSESSMENTS

HR is measured continuously to identify acutely painful situations. HR variability and pain-related cytokines (MCP-1, IL-1RA, IL-8, TGFβ1, and IL-17) are collected as measures of long-term pain. Caregivers will be asked to what degree they observe pain in their patients and how well they believe they understand their patient's expressions of emotion and pain. Pre-intervention: HR is measured 8 h/day over 2 weeks to identify potentially painful situations across four settings: physiotherapy, cast use, lifting, and personal hygiene.

INTERVENTION

Changes in procedures for identified painful situations are in the form of changes in 1) physiotherapy techniques, 2) preparations for putting on casts, 3) lifting techniques or 4) personal hygiene procedures.

DESIGN

Nineteen patients will start intervention in week 3 while 19 patients will continue data collection for another 2 weeks before procedure changes are introduced. This is done to distinguish between specific effects of changes in procedures and non-specific effects, such as caregivers increased attention.

DISCUSSION

This study will advance the field of wearable physiological sensor use in patient care.

TRIAL REGISTRATION

Registered prospectively at ClinicalTrials.gov (NCT05738278).

The roles and mechanisms of gut microbiome and metabolome in patients with cerebral infarction

As the most common type of stroke, ischemic stroke, also known as cerebral infarction (CI), with its high mortality and disability rate, has placed a huge burden on social economy and public health. Treatment methods for CI mainly include thrombectomy, thrombolysis, drug therapy, and so on. However, these treatments have certain timeliness and different side effects. In recent years, the gut-brain axis has become a hot topic, and its role in nervous system diseases has been confirmed by increasing evidences. The intestinal microbiota, as an important part of the gut-brain axis, has a non-negligible impact on the progression of CI through mechanisms such as inflammatory response and damage-associated molecular patterns, and changes in the composition of intestinal microbiota can also serve as the basis for predicting CI. At the same time, the diagnosis of CI requires more high-throughput techniques, and the analysis method of metabolomics just fits this demand. This paper reviewed the changes of intestinal microbiota in patients within CI and the effects of the intestinal microbiota on the course of CI, and summarized the therapeutic methods of the intervention with the intestinal microbiota. Furthermore, metabolic changes of CI patients were also discussed to reveal the molecular characteristics of CI and to elucidate the potential pathologic pathway of its interference.

The influential factors and non-pharmacological interventions of cognitive impairment in children with ischemic stroke

Background

The prevalence of pediatric ischemic stroke rose by 35% between 1990 and 2013. Affected patients can experience the gradual onset of cognitive impairment in the form of impaired language, memory, intelligence, attention, and processing speed, which affect 20-50% of these patients. Only few evidence-based treatments are available due to significant heterogeneity in age, pathological characteristics, and the combined epilepsy status of the affected children.

Methods

We searched the literature published by Web of Science, Scopus, and PubMed, which researched non-pharmacological rehabilitation interventions for cognitive impairment following pediatric ischemic stroke. The search period is from the establishment of the database to January 2022.

Results

The incidence of such impairment is influenced by patient age, pathological characteristics, combined epilepsy status, and environmental factors. Non-pharmacological treatments for cognitive impairment that have been explored to date mainly include exercise training, psychological intervention, neuromodulation strategies, computer-assisted cognitive training, brain-computer interfaces (BCI), virtual reality, music therapy, and acupuncture. In childhood stroke, the only interventions that can be retrieved are psychological intervention and neuromodulation strategies.

Conclusion

However, evidence regarding the efficacy of these interventions is relatively weak. In future studies, the active application of a variety of interventions to improve pediatric cognitive function will be necessary, and neuroimaging and electrophysiological measurement techniques will be of great value in this context. Larger multi-center prospective longitudinal studies are also required to offer more accurate evidence-based guidance for the treatment of patients with pediatric stroke.

Rehabilitation in Pediatric Stroke: Cognition and Behavior

Pediatric stroke is associated with a range of maladaptive cognitive and behavioral outcomes that often require targeted intervention. Despite increasing research on neuropsychological outcomes over the past decade, evidence for effective therapies and interventions for the most commonly reported cognitive and behavioral challenges is still limited. The most widely prescribed interventions address more overt deficits in sensorimotor and speech/language functions, yet interventions for higher-order cognitive, linguistic and behavioral deficits are notably less defined. Moreover, concepts of rehabilitation in adult stroke cannot be easily translated directly to pediatric populations because the effect of stroke and recovery in the developing brain takes a very different course than in the mature brain. In pediatric stroke, neuropsychological deficits often emerge gradually over time necessitating a long-term approach to intervention. Furthermore, family and school context often play a much larger role. The goal of this review is to describe cognitive and behavioral interventions for perinatal and childhood stroke, as motor rehabilitation is covered elsewhere in this issue. We also discuss cognitive aspects of current rehabilitative therapies and technology. Acknowledging the current limited state of stroke-specific rehabilitation research in children, findings from pediatric acquired brain injury intervention and use of transdiagnostic approaches lend important insights. Because there is limited support for single domain (cognitive) trainings and translation of research rehabilitation programs to clinical practice can be challenging, the value of holistic multidisciplinary approaches to improve everyday function in children and adolescents following stroke is emphasized.

Closing the Gap in Pediatric Hemorrhagic Stroke: A Systematic Review

Pediatric hemorrhagic stroke (HS) accounts for a large proportion of childhood strokes, 1 of the top 10 causes of pediatric deaths. Morbidity and mortality lead to significant socio-economic and psychosocial burdens. To understand published data on recognizing and managing children with HS, we conducted a systematic review of the literature presented here. We searched PubMed, Embase, CINAHL and the Cochrane Library databases limited to English language and included 174 studies, most conducted in the USA (52%). Terminology used interchangeably for HS included intraparenchymal/intracranial hemorrhage, spontaneous ICH, and cerebrovascular accident (CVA). Key assessments informing prognosis and management included clinical scoring (Glasgow coma scale), and neuroimaging. HS etiologies reported were systemic coagulopathy (genetic, acquired pathologic, or iatrogenic), or focal cerebrovascular lesions (brain arteriovenous malformations, cavernous malformations, aneurysms, or tumor vascularity). Several scales were used to measure outcome: Glasgow outcome score (GOS), Kings outcome score for head injury (KOSCHI), modified Rankin scale (mRS) and pediatric stroke outcome measure (PSOM). Most studies described treatments of at-risk lesions. Few studies described neurocritical care management including raised ICP, seizures, vasospasm, or blood pressure. Predictors of poor outcome included ethnicity, comorbidity, location of bleed, and hematoma >2% of total brain volume. Motor and cognitive outcomes followed independent patterns. Few studies reported on cognitive outcomes, rehabilitation, and transition of care models. Interdisciplinary approach to managing HS is urgently needed, informed by larger cohort studies targeting key clinical question (eg development of a field-guide for the clinician managing patients with HS that is reproducible internationally).

Causes and Risk Factors of Pediatric Spontaneous Intracranial Hemorrhage—A Systematic Review

Previous studies suggest that the most common cause of spontaneous intracerebral hemorrhage in children and adolescents is arteriovenous malformations (AVMs). However, an update containing recently published data on pediatric spontaneous intracranial hemorrhages is lacking. The aim of this study is to systematically analyze the published data on the etiologies and risk factors of pediatric spontaneous intracranial hemorrhage. This systematic review was performed in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A search in PubMed, Embase, Scopus, Web of Science and Cochrane Library was conducted aiming for articles published in year 2000 and later, containing data on etiology and risk factors of spontaneous intracranial hemorrhages in unselected cohorts of patients aged between 1 month and 18 years. As a result, forty studies were eligible for data extraction and final analysis. These included 7931 children and adolescents with 4009 reported etiologies and risk factors. A marked variety of reported etiologies and risk factors among studies was observed. Vascular etiologies were the most frequently reported cause of pediatric spontaneous intracranial hemorrhages (n = 1727, 43.08% of all identified etiologies or risk factors), with AVMs being the most common vascular cause (n = 1226, 70.99% of all vascular causes). Hematological and systemic causes, brain tumors, intracranial infections and cardiac causes were less commonly encountered risk factors and etiologies.

Long-Term Neurological Sequelae and Disease Burden of Japanese Encephalitis in Gansu Province, China

Background and objects:

The study aimed to evaluate the long-term neurological sequelae and the disease burden of JE in Gansu, China.

Methods:

JE patients were included as study population from 2005–2011 in Gansu, and a follow-up survey was conducted in 2007–2014. Pair-matched healthy individuals were selected as controls. All subjects underwent a neurological examination and intelligence quotient (IQ) and memory quotient (MQ) assessments. Then, the disability-adjusted life years (DALYs), and direct and indirect medical expenses were systematic assessed.

Results:

Forty-four point seven percent of the JE patients had objective neurological deficits, compared with 2.4% of controls. Subnormal intelligence was found in 21.2% of JE subjects, compared with 1.2% control who exhibited a mildly reduced IQ. Abnormal MQ scores were noted in 56.3% JE subjects, compared with only 12.7% controls. Prevalence of each sequelae caused by JE were significantly higher in adults than in younger subjects. Furthermore, median DALY lost due to JE was 9.2 per subject. Median economic cost of JE was approximately $2776.6 per subject and significantly higher in adults than in younger subjects.

Findings and Conclusions:

JE patients suffered from severe neurological sequelae and high disease burden, resulting in a significant downstream burden for both the patients (especially adults) and the healthcare system.

Increased heart rate functions as a signal of acute distress in non-communicating persons with intellectual disability

Intellectual disability (ID) affects approximately 1% of the population. Some patients with severe or profound ID are essentially non-communicating and therefore risk experiencing pain and distress without being able to notify their caregivers, which is a major health issue. This real-world proof of concept study aimed to see if heart rate (HR) monitoring could reveal whether non-communicating persons with ID experience acute pain or distress in their daily lives. We monitored HR in 14 non-communicating participants with ID in their daily environment to see if specific situations were associated with increased HR. We defined increased HR as being > 1 standard deviation above the daily mean and lasting > 5 s. In 11 out of 14 participants, increased HR indicated pain or distress in situations that were not previously suspected to be stressful, e.g. passive stretching of spastic limbs or being transported in patient lifts. Increased HR suggesting joy was detected in three participants (during car rides, movies). In some situations that were previously suspected to be stressful, absence of HR increase suggested absence of pain or distress. We conclude that HR monitoring may identify acute pain and distress in non-communicating persons with ID, allowing for improved health care for this patient group.

Pediatric traumatic brain injury and abusive head trauma

Childhood traumatic brain injury (TBI) commonly occurs during brain development and can have direct, immediately observable neurologic, cognitive, and behavioral consequences. However, it can also disrupt subsequent brain development, and long-term outcomes are a combination of preinjury development and abilities, consequences of brain injury, as well as delayed impaired development of skills that were immature at the time of injury. There is a growing number of studies on mild TBI/sport-related concussions, describing initial symptoms and their evolution over time and providing guidelines for effective management of symptoms and return to activity/school/sports. Mild TBI usually does not lead to long-term cognitive or academic consequences, despite reports of behavioral/psychologic issues postinjury. Regarding moderate to severe TBI, injury to the brain is more severe, with evidence of a number of detrimental consequences in various domains. Patients can display neurologic impairments (e.g., motor deficits, signs of cerebellar disorder, posttraumatic epilepsy), medical problems (e.g., endocrine pituitary deficits, sleep-wake abnormalities), or sensory deficits (e.g., visual, olfactory deficits). The most commonly reported deficits are in the cognitive-behavioral field, which tend to be significantly disabling in the long-term, impacting the development of autonomy, socialization and academic achievement, participation, quality of life, and later, independence and ability to enter the workforce (e.g., intellectual deficits, slow processing speed, attention, memory, executive functions deficits, impulsivity, intolerance to frustration). A number of factors influence outcomes following pediatric TBI, including preinjury stage of development and abilities, brain injury severity, age at injury (with younger age at injury most often associated with worse outcomes), and a number of family/environment factors (e.g., parental education and occupation, family functioning, parenting style, warmth and responsiveness, access to rehabilitation and care). Interventions should identify and target these specific factors, given their major role in postinjury outcomes. Abusive head trauma (AHT) occurs in very young children (most often <6 months) and is a form of severe TBI, usually associated with delay before appropriate care is sought. Outcomes are systematically worse following AHT than following accidental TBI, even when controlling for age at injury and injury severity. Children with moderate to severe TBI and AHT usually require specific, coordinated, multidisciplinary, and long-term rehabilitation interventions and school adaptations, until transition to adult services. Interventions should be patient- and family-centered, focusing on specific goals, comprising education about TBI, and promoting optimal parenting, communication, and collaborative problem-solving.