Emerging methods for measuring physical activity using accelerometry in children and adolescents with neuromotor disorders: a narrative review

BACKGROUND

Children and adolescents with neuromotor disorders need regular physical activity to maintain optimal health and functional independence throughout their development. To this end, reliable measures of physical activity are integral to both assessing habitual physical activity and testing the efficacy of the many interventions designed to increase physical activity in these children. Wearable accelerometers have been used for children with neuromotor disorders for decades; however, studies most often use disorder-specific cut points to categorize physical activity intensity, which lack generalizability to a free-living environment. No reviews of accelerometer data processing methods have discussed the novel use of machine learning techniques for monitoring physical activity in children with neuromotor disorders.

METHODS

In this narrative review, we discuss traditional measures of physical activity (including questionnaires and objective accelerometry measures), the limitations of standard analysis for accelerometry in this unique population, and the potential benefits of applying machine learning approaches. We also provide recommendations for using machine learning approaches to monitor physical activity.

CONCLUSIONS

While wearable accelerometers provided a much-needed method to quantify physical activity, standard cut point analyses have limitations in children with neuromotor disorders. Machine learning models are a more robust method of analyzing accelerometer data in pediatric neuromotor disorders and using these methods over disorder-specific cut points is likely to improve accuracy of classifying both type and intensity of physical activity. Notably, there remains a critical need for further development of classifiers for children with more severe motor impairments, preschool aged children, and children in hospital settings.

Patient-report and caregiver-report measures of rehabilitation service use following acquired brain injury: a systematic review

OBJECTIVE

To review patient-report/caregiver-report measures of rehabilitation service use following acquired brain injury (ABI).

DATA SOURCES

Medline, APA PsycINFO, Embase and CINAHL were searched on November 2021 and November 2022. Authors were contacted if measures were not included in manuscripts/appendices.

STUDY SELECTION

Included articles were empirical research or a research protocol, available in English and described measures of patient report/caregiver report of rehabilitation service use post-ABI via quantitative or qualitative methods. Two reviewers independently screened 5290 records using DistillerSR. Discrepancies were resolved by team adjudication.

DATA EXTRACTION

Data extraction was piloted with high levels of agreement (k=.94). Data were extracted by a single member with team meetings to seek guidance as needed. Data included administration characteristics (reporter, mode of administration, recall period), psychometric evidence and dimensions assessed (types of services, setting, frequency, duration, intensity, qualitative aspects).

DATA SYNTHESIS

One hundred and fifty-two measures were identified from 85 quantitative, 56 qualitative and 3 psychometric studies. Psychometric properties were reported for four measures, all of which focused on satisfaction. Most measures inquired about the type of rehabilitation services used, with more than half assessing functional (eg, physical therapy) and behavioural health rehabilitation services, but fewer than half assessing community and academic reintegration (eg, special education, vocational rehabilitation) or cognitive (eg, neuropsychology) services. Fewer than half assessed qualitative aspects (eg, satisfaction). Recall periods ranged from 1 month to 'since the ABI event' or focused on current use. Of measures that could be accessed (n=71), many included a limited checklist of types of services used. Very few measures assessed setting, frequency, intensity or duration.

CONCLUSIONS

Despite widespread interest, the vast majority of measures have not been validated and are limited in scope. Use of gold-standard psychometric methods to develop and validate a comprehensive patient-report/caregiver-report measure of rehabilitation service use would have wide-ranging implications for improving rehabilitation research in ABI.

Brain-Derived Neurotrophic Factor in Pediatric Acquired Brain Injury and Recovery

We review emerging preclinical and clinical evidence regarding brain-derived neurotrophic factor (BDNF) protein, genotype, and DNA methylation (DNAm) as biomarkers of outcomes in three important etiologies of pediatric acquired brain injury (ABI), traumatic brain injury, global cerebral ischemia, and stroke. We also summarize evidence suggesting that BDNF is (1) involved in the biological embedding of the psychosocial environment, (2) responsive to rehabilitative therapies, and (3) potentially modifiable. BDNF's unique potential as a biomarker of neuroplasticity and neural repair that is reflective of and responsive to both pre- and post-injury environmental influences separates it from traditional protein biomarkers of structural brain injury with exciting potential to advance pediatric ABI management by increasing the accuracy of prognostic tools and informing clinical decision making through the monitoring of therapeutic effects.

Effects of inpatient rehabilitation after acute care on motor, neuropsychological and behavioral outcomes in children with severe traumatic brain injury

PURPOSE

An observational study of children with severe traumatic brain injury (TBI) (Approaches and Decisions in Acute Pediatric TBI [ADAPT] Trial) demonstrated the benefits of inpatient rehabilitation on functional outcomes for those with more severely impaired consciousness when medically stable. We conducted a secondary analysis to assess whether using an inpatient rehabilitation or skilled nursing facility after acute hospitalization was associated with better motor, neuropsychological, and behavioral outcomes compared to receiving only non-inpatient rehabilitation among children with severe TBI.

MATERIALS AND METHODS

We included 180 children who used an inpatient rehabilitation or skilled nursing facility and 74 children who only received non-inpatient rehabilitation from the ADAPT trial. At 12 months post-injury, children underwent tests of motor skills, intellectual functioning, verbal learning, memory, processing speed, and cognitive flexibility. Parents/guardians rated children's executive function and behaviors. We performed inverse probability weighting to adjust for potential confounders.

RESULTS

No significant differences were found in any motor, neuropsychological, or behavioral measures between children receiving inpatient rehabilitation and children receiving only non-inpatient rehabilitation.

CONCLUSIONS

Analyses of comprehensive outcomes did not show differences between children receiving inpatient rehabilitation and children receiving only non-inpatient rehabilitation, suggesting a need for more research on specific components of the rehabilitation process.

Barriers to Care and Perceived Need for Mental Health Services Among Adolescent and Emerging Adult Survivors of Pediatric Brain Tumors

Purpose: Pediatric brain tumor survivors (PBTS) commonly experience mental health challenges, which can be exacerbated during adolescence and emerging adulthood (AEA). We examined survivors and caregivers' perceived need for mental health services and barriers to receiving mental health care. Methods: Families completed surveys to assess perceived need for mental health services, socioemotional impairment, and barriers to mental health services. Survivors were between 13 and 25 years of age and were at least 5 years from diagnosis. Results: Sixty-nine caregiver-PBTS dyads participated, as well as 18 survivors and 20 caregivers who participated individually. Approximately half of survivors were male (n = 57, 52.3%), 85% (n = 93) were White, and their average age was 19.31. Most caregivers (n = 63, 70.8%) and survivors (n = 55, 63.2%) endorsed need for services for the survivors. Adolescents endorsed more barriers related to perceived helpfulness, t(18) = 2.3, p = 0.03, d = 0.54, and effects of services, t(18) = 3.8, p < 0.001, d = 0.88, than their caregivers. Emerging adults, t(34) = 2.4, p = 0.02, d = 0.41, endorsed more content barriers than their caregivers.. Discussion: Both survivors and their caregivers reported obstacles to accessing mental health services such as perceived lack of need, concerns regarding the effectiveness and usefulness of services, and limited knowledge about the content of services. Psychoeducation and psychosocial screening can support families in understanding survivors' need for mental health services.

Assessment of Brain Magnetic Resonance and Spectroscopy Imaging Findings and Outcomes After Pediatric Cardiac Arrest

Importance

Morbidity and mortality after pediatric cardiac arrest are chiefly due to hypoxic-ischemic brain injury. Brain features seen on magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) after arrest may identify injury and aid in outcome assessments.

Objective

To analyze the association of brain lesions seen on T2-weighted MRI and diffusion-weighted imaging and N-acetylaspartate (NAA) and lactate concentrations seen on MRS with 1-year outcomes after pediatric cardiac arrest.

Design, Setting, and Participants

This multicenter cohort study took place in pediatric intensive care units at 14 US hospitals between May 16, 2017, and August 19, 2020. Children aged 48 hours to 17 years who were resuscitated from in-hospital or out-of-hospital cardiac arrest and who had a clinical brain MRI or MRS performed within 14 days postarrest were included in the study. Data were analyzed from January 2022 to February 2023.

Exposure

Brain MRI or MRS.

Main Outcomes and Measures

The primary outcome was an unfavorable outcome (either death or survival with a Vineland Adaptive Behavior Scales, Third Edition, score of <70) at 1 year after cardiac arrest. MRI brain lesions were scored according to region and severity (0 = none, 1 = mild, 2 = moderate, 3 = severe) by 2 blinded pediatric neuroradiologists. MRI Injury Score was a sum of T2-weighted and diffusion-weighted imaging lesions in gray and white matter (maximum score, 34). MRS lactate and NAA concentrations in the basal ganglia, thalamus, and occipital-parietal white and gray matter were quantified. Logistic regression was performed to determine the association of MRI and MRS features with patient outcomes.

Results

A total of 98 children, including 66 children who underwent brain MRI (median [IQR] age, 1.0 [0.0-3.0] years; 28 girls [42.4%]; 46 White children [69.7%]) and 32 children who underwent brain MRS (median [IQR] age, 1.0 [0.0-9.5] years; 13 girls [40.6%]; 21 White children [65.6%]) were included in the study. In the MRI group, 23 children (34.8%) had an unfavorable outcome, and in the MRS group, 12 children (37.5%) had an unfavorable outcome. MRI Injury Scores were higher among children with an unfavorable outcome (median [IQR] score, 22 [7-32]) than children with a favorable outcome (median [IQR] score, 1 [0-8]). Increased lactate and decreased NAA in all 4 regions of interest were associated with an unfavorable outcome. In a multivariable logistic regression adjusted for clinical characteristics, increased MRI Injury Score (odds ratio, 1.12; 95% CI, 1.04-1.20) was associated with an unfavorable outcome.

Conclusions and Relevance

In this cohort study of children with cardiac arrest, brain features seen on MRI and MRS performed within 2 weeks after arrest were associated with 1-year outcomes, suggesting the utility of these imaging modalities to identify injury and assess outcomes.

Brain-derived neurotrophic factor (BDNF) epigenomic modifications and brain-related phenotypes in humans: A systematic review

Epigenomic modifications of the brain-derived neurotrophic factor (BDNF) gene have been postulated to underlie the pathogenesis of neurodevelopmental, psychiatric, and neurological conditions. This systematic review summarizes current evidence investigating the association of BDNF epigenomic modifications (DNA methylation, non-coding RNA, histone modifications) with brain-related phenotypes in humans. A novel contribution is our creation of an open access web-based application, the BDNF DNA Methylation Map, to interactively visualize specific positions of CpG sites investigated across all studies for which relevant data were available. Our literature search of four databases through September 27, 2021 returned 1701 articles, of which 153 met inclusion criteria. Our review revealed exceptional heterogeneity in methodological approaches, hindering the identification of clear patterns of robust and/or replicated results. We summarize key findings and provide recommendations for future epigenomic research. The existing literature appears to remain in its infancy and requires additional rigorous research to fulfill its potential to explain BDNF-linked risk for brain-related conditions and improve our understanding of the molecular mechanisms underlying their pathogenesis.

Effects of inpatient rehabilitation after acute care on functional and quality-of-life outcomes in children with severe traumatic brain injury

OBJECTIVE

Few studies have assessed the effectiveness of the rehabilitation process in children surviving severe traumatic brain injury (TBI). We evaluated whether receiving inpatient rehabilitation after acute hospitalization was associated with better functional outcomes compared to receiving only non-inpatient rehabilitation in children with severe TBI and explored an effect modification for Glasgow Coma Scale (GCS) score at hospital discharge.

METHODS

We included 254 children who received rehabilitation following severe TBI from a multinational observational study. The Pediatric Glasgow Outcome Scale - Extended (GOS-E Peds), parent/guardian-reported and child-reported Pediatric Quality of Life Inventory (PedsQL) at 12 months post-injury were assessed and described using summary statistics. Unadjusted and propensity score-weighted linear/ordinal logistic regression modeling were also performed.

RESULTS

180 children received inpatient rehabilitation and 74 children received only non-inpatient rehabilitation after acute hospitalization. Among children with a GCS<13 at discharge, those receiving inpatient rehabilitation had a more favorable GOS-E Peds score (OR = 0.12, p = 0.045). However, no such association was observed in children with a higher GCS. We found no differences in PedsQL scores between rehabilitation groups.

CONCLUSIONS

Future studies are warranted to confirm the benefits of inpatient rehabilitation for children with more severely impaired consciousness when medically stable.

Association of Blood-Based Brain Injury Biomarker Concentrations With Outcomes After Pediatric Cardiac Arrest

IMPORTANCE

Families and clinicians have limited validated tools available to assist in estimating long-term outcomes early after pediatric cardiac arrest. Blood-based brain-specific biomarkers may be helpful tools to aid in outcome assessment.

OBJECTIVE

To analyze the association of blood-based brain injury biomarker concentrations with outcomes 1 year after pediatric cardiac arrest.

DESIGN, SETTING, AND PARTICIPANTS

The Personalizing Outcomes After Child Cardiac Arrest multicenter prospective cohort study was conducted in pediatric intensive care units at 14 academic referral centers in the US between May 16, 2017, and August 19, 2020, with the primary investigators blinded to 1-year outcomes. The study included 120 children aged 48 hours to 17 years who were resuscitated after cardiac arrest, had pre-cardiac arrest Pediatric Cerebral Performance Category scores of 1 to 3 points, and were admitted to an intensive care unit after cardiac arrest.

EXPOSURE

Cardiac arrest.

MAIN OUTCOMES AND MEASURES

The primary outcome was an unfavorable outcome (death or survival with a Vineland Adaptive Behavior Scales, third edition, score of <70 points) at 1 year after cardiac arrest. Glial fibrillary acidic protein (GFAP), ubiquitin carboxyl-terminal esterase L1 (UCH-L1), neurofilament light (NfL), and tau concentrations were measured in blood samples from days 1 to 3 after cardiac arrest. Multivariate logistic regression and area under the receiver operating characteristic curve (AUROC) analyses were performed to examine the association of each biomarker with outcomes on days 1 to 3.

RESULTS

Among 120 children with primary outcome data available, the median (IQR) age was 1.0 (0-8.5) year; 71 children (59.2%) were male. A total of 5 children (4.2%) were Asian, 19 (15.8%) were Black, 81 (67.5%) were White, and 15 (12.5%) were of unknown race; among 110 children with data on ethnicity, 11 (10.0%) were Hispanic, and 99 (90.0%) were non-Hispanic. Overall, 70 children (58.3%) had a favorable outcome, and 50 children (41.7%) had an unfavorable outcome, including 43 deaths. On days 1 to 3 after cardiac arrest, concentrations of all 4 measured biomarkers were higher in children with an unfavorable vs a favorable outcome at 1 year. After covariate adjustment, NfL concentrations on day 1 (adjusted odds ratio [aOR], 5.91; 95% CI, 1.82-19.19), day 2 (aOR, 11.88; 95% CI, 3.82-36.92), and day 3 (aOR, 10.22; 95% CI, 3.14-33.33); UCH-L1 concentrations on day 2 (aOR, 11.27; 95% CI, 3.00-42.36) and day 3 (aOR, 7.56; 95% CI, 2.11-27.09); GFAP concentrations on day 2 (aOR, 2.31; 95% CI, 1.19-4.48) and day 3 (aOR, 2.19; 95% CI, 1.19-4.03); and tau concentrations on day 1 (aOR, 2.44; 95% CI, 1.14-5.25), day 2 (aOR, 2.28; 95% CI, 1.31-3.97), and day 3 (aOR, 2.04; 95% CI, 1.16-3.57) were associated with an unfavorable outcome. The AUROC models were significantly higher with vs without the addition of NfL on day 2 (AUROC, 0.932 [95% CI, 0.877-0.987] vs 0.871 [95% CI, 0.793-0.949]; P = .02) and day 3 (AUROC, 0.921 [95% CI, 0.857-0.986] vs 0.870 [95% CI, 0.786-0.953]; P = .03).

CONCLUSIONS AND RELEVANCE

In this cohort study, blood-based brain injury biomarkers, especially NfL, were associated with an unfavorable outcome at 1 year after pediatric cardiac arrest. Additional evaluation of the accuracy of the association between biomarkers and neurodevelopmental outcomes beyond 1 year is needed.

Brain-Derived Neurotrophic Factor Val66Met and Behavioral Adjustment after Early Childhood Traumatic Brain Injury

The present study examined the differential effect of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism on behavioral adjustment in children with traumatic brain injury (TBI) relative to children with orthopedic injury (OI). Participants were drawn from a prospective, longitudinal study of children who sustained a TBI (n = 69) or OI (n = 72) between 3 and 7 years of age. Parents completed the Child Behavior Checklist (CBCL) at the immediate post-acute period, 6, 12, and 18 months after injury, and an average of 3.5 and 7 years after injury. Longitudinal mixed models examined the BDNF Val66Met allele status (Met carriers vs. Val/Val homozygotes) × injury group (TBI vs. OI) interaction in association with behavioral adjustment. After adjusting for continental ancestry, socioeconomic status, time post-injury, and pre-injury functioning, the allele status × injury group interaction was statistically significant for Internalizing, Externalizing, and Total Behavior problems. Post hoc within-group analysis suggested a consistent trend of poorer behavioral adjustment in Met carriers relative to Val/Val homozygotes in the TBI group; in contrast, the opposite trend was observed in the OI group. These within-group differences, however, did not reach statistical significance. The results support a differential effect of the BDNF Val66Met polymorphism on behavioral adjustment in children with early TBI relative to OI, and suggest that the Met allele associated with reduced activity-dependent secretion of BDNF may impart risk for poorer long-term behavioral adjustment in children with TBI.

Association of ethnicity and adaptive functioning with health-related quality of life in pediatric myelomeningocele

PURPOSE

The purpose of this study was to evaluate associations of ethnicity and adaptive function with health-related quality of life (HRQOL) in youths with spina bifida myelomeningocele (SBM).

METHODS

Participants included Hispanic (n = 75) and non-Hispanic White (n = 86) children and adolescents with SBM. Participants completed ratings of adaptive function and SBM-specific HRQOL. A series of linear multiple regression models was computed to investigate whether ethnicity moderates the relation between adaptive function and HRQOL.

RESULTS

Results showed that greater adaptive function was associated with higher HRQOL. While no relations were found between ethnicity and HRQOL, a significant interaction was observed between adaptive function and ethnicity over and above other terms. Although groups did not differ on HRQOL at lower levels of adaptive function, Hispanic participants rated higher HRQOL relative to non-Hispanic White participants at higher levels of adaptive function. Further analysis showed this was true of both nonmotor and motor aspects of adaptive function.

CONCLUSION

Results suggested complex relations between ethnicity and adaptive function with HRQOL, highlighting the importance of optimizing adaptive functioning in youth with SBM.

A-5 Brain-Derived Neurotrophic Factor Val66Met and Neuropsychological Functioning Following Early Childhood Traumatic Brain Injury

Objective

The present study examined the differential effect of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism on neuropsychological functioning in children with traumatic brain injury (TBI) relative to children with orthopedic injury (OI).

Method

Participants were drawn from a prospective, longitudinal study of children who sustained a TBI (n = 69) or OI (n = 72) between 3 and 7 years of age. Children completed a battery of neuropsychological measures targeting attention, memory, and executive functions at four time points spanning the immediate post-acute period to 18 months post-injury. Children also completed a comparable age-appropriate battery of measures approximately 7 years post-injury. Parents rated children’s executive functioning at all time points.

Results

Longitudinal mixed models revealed a significant allele status x injury group interaction for verbal fluency (p = 0.007) and a non-significant trend for parent-rated dysexecutive behaviors (p = 0.069), and cross-sectional models at 7 years post-injury revealed a non-significant trend for the allele status x injury group interaction for fluid reasoning skills (p = 0.074). Post hoc analyses suggested a consistent pattern of poorer neuropsychological functioning in Met carriers relative to Val/Val homozygotes in the TBI group; in contrast, the opposite trend was observed in the OI group.

Conclusions

The results suggest a differential effect of the BDNF Val66Met polymorphism on verbal fluency, dysexecutive behaviors, and fluid reasoning skills in children with early TBI relative to OI, and that the Met allele—associated with reduced activity-dependent secretion of BDNF—confers risk for poorer neuropsychological functioning in children with TBI.

Acute Brain-Derived Neurotrophic Factor DNA Methylation Trajectories in Cerebrospinal Fluid and Associations With Outcomes Following Severe Traumatic Brain Injury in Adults

Background. Epigenetic biomarkers have the potential to explain outcome heterogeneity following traumatic brain injury (TBI) but are largely unexplored. Objective. This exploratory pilot study characterized brain-derived neurotrophic factor (BDNF) DNA methylation trajectories following severe TBI. Methods. Brain-derived neurotrophic factor DNA methylation trajectories in cerebrospinal fluid (CSF) over the first 5 days following severe TBI in 112 adults were examined in association with 3- and 12-month outcomes. Results. Group-based trajectory analysis revealed low and high DNA methylation groups at two BDNF cytosine-phosphate-guanine (CpG) targets that showed suggestive associations (P < .05) with outcomes. Membership in the high DNA methylation groups was associated with better outcomes after controlling for age, sex, and injury severity. Associations of age × trajectory group interactions with outcomes at a third CpG site revealed a pattern of the same or better outcomes with higher ages in the high DNA methylation group and worse outcomes with higher ages in the low DNA methylation group. Conclusions. Although no observed associations met the empirical significance threshold after correcting for multiple comparisons, suggestive associations of the main effect models were consistent in their direction of effect and were observed across two CpG sites and two outcome time points. Results suggest that higher acute CSF BDNF DNA methylation may promote recovery following severe TBI in adults, and this effect may be more robust with higher age. While the results require replication in larger and racially diverse independent samples, BDNF DNA methylation may serve as an early postinjury biomarker helping to explain outcome heterogeneity following TBI.

Paths to Successful Translation of New Therapies for Severe Traumatic Brain Injury in the Golden Age of Traumatic Brain Injury Research: A Pittsburgh Vision

New neuroprotective therapies for severe traumatic brain injury (TBI) have not translated from pre-clinical to clinical success. Numerous explanations have been suggested in both the pre-clinical and clinical arenas. Coverage of TBI in the lay press has reinvigorated interest, creating a golden age of TBI research with innovative strategies to circumvent roadblocks. We discuss the need for more robust therapies. We present concepts for traditional and novel approaches to defining therapeutic targets. We review lessons learned from the ongoing work of the pre-clinical drug and biomarker screening consortium Operation Brain Trauma Therapy and suggest ways to further enhance pre-clinical consortia. Biomarkers have emerged that empower choice and assessment of target engagement by candidate therapies. Drug combinations may be needed, and it may require moving beyond conventional drug therapies. Precision medicine may also link the right therapy to the right patient, including new approaches to TBI classification beyond the Glasgow Coma Scale or anatomical phenotyping-incorporating new genetic and physiologic approaches. Therapeutic breakthroughs may also come from alternative approaches in clinical investigation (comparative effectiveness, adaptive trial design, use of the electronic medical record, and big data). The full continuum of care must also be represented in translational studies, given the important clinical role of pre-hospital events, extracerebral insults in the intensive care unit, and rehabilitation. TBI research from concussion to coma can cross-pollinate and further advancement of new therapies. Misconceptions can stifle/misdirect TBI research and deserve special attention. Finally, we synthesize an approach to deliver therapeutic breakthroughs in this golden age of TBI research.

Cumulative Influence of Inflammatory Response Genetic Variation on Long-Term Neurobehavioral Outcomes after Pediatric Traumatic Brain Injury Relative to Orthopedic Injury: An Exploratory Polygenic Risk Score

The addition of genetic factors to prognostic models of neurobehavioral recovery following pediatric traumatic brain injury (TBI) may account for unexplained heterogeneity in outcomes. The present study examined the cumulative influence of candidate genes involved in the inflammatory response on long-term neurobehavioral recovery in children with early childhood TBI relative to children with orthopedic injuries (OI). Participants were drawn from a prospective, longitudinal study evaluating outcomes of children who sustained TBI (n = 67) or OI (n = 68) between the ages of 3 and 7 years. Parents completed ratings of child executive function and behavior at an average of 6.8 years after injury. Exploratory unweighted and weighted polygenic risk scores (PRS) were constructed from single nucleotide polymorphisms (SNPs) across candidate inflammatory response genes (i.e., angiotensin converting enzyme [ACE], brain-derived neurotrophic factor [BDNF], interleukin-1 receptor antagonist [IL1RN], and 5'-ectonucleotidase [NT5E]) that showed nominal (p ≤ 0.20) associations with outcomes in the TBI group. Linear regression models tested the PRS × injury group (TBI vs. OI) interaction term and post-hoc analyses examined the effect of PRS within each injury group. Higher inflammatory response PRS were associated with more executive dysfunction and behavior problems in children with TBI but not in children with OI. The cumulative influence of inflammatory response genes as measured by PRS explained additional variance in long-term neurobehavioral outcomes, over and above well-established predictors and single candidate SNPs tested individually. The results suggest that some of the unexplained heterogeneity in long-term neurobehavioral outcomes following pediatric TBI may be attributable to a child's genetic predisposition to a greater or lesser inflammatory response to TBI.

Epigenetic Effects on Pediatric Traumatic Brain Injury Recovery (EETR): An Observational, Prospective, Longitudinal Concurrent Cohort Study Protocol

Introduction: Unexplained heterogeneity in outcomes following pediatric traumatic brain injury (TBI) is one of the most critical barriers to the development of effective prognostic tools and therapeutics. The addition of personal biological factors to our prediction models may account for a significant portion of unexplained variance and advance the field toward precision rehabilitation medicine. The overarching goal of the Epigenetic Effects on Pediatric Traumatic Brain Injury Recovery (EETR) study is to investigate an epigenetic biomarker involved in both childhood adversity and postinjury neuroplasticity to better understand heterogeneity in neurobehavioral outcomes following pediatric TBI. Our primary hypothesis is that childhood adversity will be associated with worse neurobehavioral recovery in part through an epigenetically mediated reduction in brain-derived neurotrophic factor (BDNF) expression in response to TBI. Methods and analysis: EETR is an observational, prospective, longitudinal concurrent cohort study of children aged 3-18 years with either TBI (n = 200) or orthopedic injury (n = 100), recruited from the UPMC Children's Hospital of Pittsburgh. Participants complete study visits acutely and at 6 and 12 months postinjury. Blood and saliva biosamples are collected at all time points-and cerebrospinal fluid (CSF) when available acutely-for epigenetic and proteomic analysis of BDNF. Additional measures assess injury characteristics, pre- and postinjury child neurobehavioral functioning, childhood adversity, and potential covariates/confounders. Recruitment began in July 2017 and will occur for ~6 years, with data collection complete by mid-2023. Analyses will characterize BDNF DNA methylation and protein levels over the recovery period and investigate this novel biomarker as a potential biological mechanism underlying the known association between childhood adversity and worse neurobehavioral outcomes following pediatric TBI. Ethics and dissemination: The study received ethics approval from the University of Pittsburgh Institutional Review Board. Participants and their parents provide informed consent/assent. Research findings will be disseminated via local and international conference presentations and manuscripts submitted to peer-reviewed journals. Trial Registration: The study is registered with clinicaltrials.org (ClinicalTrials.gov Identifier: NCT04186429).

Parenting Behaviors after Moderate - Severe Traumatic Injury in Early Childhood

Purpose: Examine the impact of traumatic brain injury (TBI) on parenting behavior over time. Method: Included 206 children (3-7 years old) with moderate to severe TBI or orthopedic injury, using a prospective longitudinal cohort study design. Assessments completed at baseline, 6-months, 12-months, 18-months, 3.5 years, and 6.8 years after injury. Dependent variables included authoritative, permissive, and authoritarian parenting. Results: Injury characteristics had limited impact on parenting behaviors over time. Levels of authoritative parenting remained stable over time; however, levels of warmth and involvement declined over time for those with TBI. Levels of permissive and authoritarian parenting declined for all participants by 3.5 years post injury. SES and stressors impacted parenting behaviors. Conclusions: While there was limited effect of TBI on parenting behavior over time, it remains unclear how individuals respond to these parenting behaviors years after injury. Clinicians should monitor family and parenting behaviors to foster an environment to promote positive recovery.

PICU-Based Rehabilitation and Outcomes Assessment: A Survey of Pediatric Critical Care Physicians

OBJECTIVES

Characterize current practices for PICU-based rehabilitation, and physician perceptions and attitudes, barriers, resources, and outcome assessment in contemporary PICU settings.

DESIGN

International, self-administered, quantitative, cross-sectional survey.

SETTING

Online survey distributed from March 2017 to April 2017.

PATIENTS OR SUBJECTS

Pediatric critical care physicians who subscribed to email distribution lists of the Pediatric Acute Lung Injury and Sepsis Investigators, the Pediatric Neurocritical Care Research Group, or the Prevalence of Acute Critical Neurological Disease in Children: A Global Epidemiological Assessment study group, and visitors to the World Federation of Pediatric Intensive and Critical Care Societies website.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 170 subjects who began the survey, 148 completed it. Of those who completed the optional respondent information, most reported working in an academic medical setting and were located in the United States. The main findings were 1) a large majority of PICU physicians reported working in institutions with no guidelines for PICU-based rehabilitation, but expressed interest in developing and implementing such guidelines; 2) despite this lack of guidelines, an overwhelming majority of respondents reported that their current practices would involve consultation of multiple rehabilitation services for each case example provided; 3) PICU physicians believed that additional research evidence is needed to determine efficacy and optimal implementation of PICU-based rehabilitation; 4) PICU physicians reported significant barriers to implementation of PICU-based rehabilitation across centers; and 5) low routine assessment of long-term functional outcomes of PICU patients, although some centers have developed multidisciplinary follow-up programs.

CONCLUSIONS

Physicians lack PICU-based rehabilitation guidelines despite great interest and current practices involving a high degree of PICU-based rehabilitation consultation. Data are needed to identify best practices and necessary resources in the delivery of ICU-based multidisciplinary rehabilitation and long-term functional outcomes assessment to optimize recovery of children and families affected by critical illness.

Genetic Influences on Behavioral Outcomes After Childhood TBI: A Novel Systems Biology-Informed Approach

Objectives: To test whether genetic associations with behavioral outcomes after early childhood traumatic brain injury (TBI) are enriched for biologic pathways underpinning neurocognitive and behavioral networks.

Design: Cross-sectional evaluation of the association of genetic factors with early (~ 6 months) and long-term (~ 7 years) post-TBI behavioral outcomes. We combined systems biology and genetic association testing methodologies to identify biologic pathways associated with neurocognitive and behavior outcomes after TBI. We then evaluated whether genes/single nucleotide polymorphism (SNPs) associated with these biologic pathways were more likely to demonstrate a relationship (i.e., enrichment) with short and long-term behavioral outcomes after early childhood TBI compared to genes/SNPs not associated with these biologic pathways.

Setting: Outpatient research setting.

Participants:140 children, ages 3–6:11 years at time of injury, admitted for a TBI or orthopedic injury (OI).

Interventions: Not Applicable.

Main Outcome Measures: Child behavior checklist total problems T score.

Results: Systems biology methodology identified neuronal systems and neurotransmitter signaling (Glutamate receptor, dopamine, serotonin, and calcium signaling), inflammatory response, cell death, immune systems, and brain development as important biologic pathways to neurocognitive and behavioral outcomes after TBI. At 6 months post injury, the group (TBI versus OI) by polymorphism interaction was significant when the aggregate signal from the highest ranked 40% of case gene associations was compared to the control set of genes. At ~ 7 years post injury, the selected polymorphisms had a significant main effect after controlling for injury type when the aggregate signal from the highest ranked 10% of the case genes were compared to the control set of genes

Conclusions: Findings demonstrate the promise of applying a genomics approach, informed by systems biology, to understanding behavioral recovery after pediatric TBI. A mixture of biologic pathways and processes are associated with behavioral recovery, specifically genes associated with cell death, inflammatory response, neurotransmitter signaling, and brain development. These results provide insights into the complex biology of TBI recovery.

The Moderating Effect of the Ankyrin Repeat and Kinase Domain Containing One Gene on the Association of Family Environment with Longitudinal Executive Function following Traumatic Brain Injury in Early Childhood: A Preliminary Study

This study examined whether the ankyrin repeat and kinase domain containing 1 gene (ANKK1) C/T single-nucleotide polymorphism (SNP) rs1800497 moderated the association of family environment with long-term executive function (EF) following traumatic injury in early childhood. Caregivers of children with traumatic brain injury (TBI) and children with orthopedic injury completed the Behavior Rating Inventory of Executive Function (BRIEF) at post-injury visits. DNA was collected to identify the rs1800497 genotype in the ANKK1 gene. General linear models examined gene-environment interactions as moderators of the effects of TBI on EF at two times post-injury (12 months and 7 years). At 12 months post-injury, analyses revealed a significant three-way interaction of genotype with level of permissive parenting and injury type. Post hoc analyses showed genetic effects were more pronounced for children with TBI from more positive family environments, such that children with TBI who were carriers of the risk allele (T-allele) had significantly poorer EF compared with non-carriers only when they were from more advantaged environments. At 7 years post-injury, analyses revealed a significant two-way interaction of genotype with level of authoritarian parenting. Post hoc analyses found that carriers of the risk allele had significantly poorer EF compared with non-carriers only when they were from more advantaged environments. These results suggest a gene-environment interaction involving the ANKK1 gene as a predictor of EF in a pediatric injury population. The findings highlight the importance of considering environmental influences in future genetic studies on recovery following TBI and other traumatic injuries in childhood.

Recovery Trajectories of Executive Functioning After Pediatric TBI: A Latent Class Growth Modeling Analysis

OBJECTIVE

To identify latent trajectories of executive functioning (EF) recovery overtime after childhood traumatic brain injury (TBI) and examine the predictive value of known risk factors within and across recovery trajectories using latent class growth modeling (LCGM).

METHOD

A total of 206 children between the ages of 3 and 7 years with a moderate to severe TBI or orthopedic injury (OI) were included. LCGM was applied to identify longitudinal trajectories of postinjury EF as assessed by the Behavior Rating Inventory of Executive Functioning General Executive Composite (GEC). Separate models were estimated for the TBI and OI groups.

RESULTS

Two TBI trajectories-normal limits (70.8%) and clinically elevated (29.2%)-and 3 OI trajectories-normal limits (20.9%), subclinical (49.0%), and clinically elevated (30.17%)-were identified. Baseline GEC was the only predictor of class membership for all models. Both TBI trajectories demonstrated an increase in GEC over time, whereas only 1 of the 3 OI classes demonstrated this pattern. Family variables were associated with GEC across trajectories.

CONCLUSION

The lack of association of injury characteristics with trajectory class membership highlights the heterogeneity in recovery after pediatric TBI. Associations of EF trajectories with family factors underscore the importance of involving the family in interventions for children with traumatic injuries.

Long-term classroom functioning and its association with neuropsychological and academic performance following traumatic brain injury during early childhood

OBJECTIVE

The present study utilized ecobehavioral assessment to examine classroom functioning several years following early childhood traumatic brain injury (TBI) or orthopedic injury (OI) and its association with injury factors, neuropsychological abilities, and academic performance.

METHOD

Participants included 39 children with moderate to severe TBI and 51 children with OI sustained between ages 3 and 7 years. At 7.2 (± 1.3) years post injury, ecobehavioral assessment was used to examine classroom functioning. Additional outcomes included neuropsychological tests, parent and teacher ratings of dysexecutive behavior, and teacher ratings of academic performance. Groups were compared on measures controlling for demographic characteristics, and associations among outcomes were examined using linear regression.

RESULTS

Children with TBI showed lower academic engagement relative to children with OI, as well as more frequent individual teacher attention for children with more severe injuries. For children with TBI, difficulties in classroom functioning were associated with lower cognitive flexibility and higher parent and teacher ratings of dysexecutive behavior. Lower scores on a test of fluid reasoning and a greater frequency of individual teacher attention were also associated with lower academic performance in children with TBI.

CONCLUSIONS

Difficulties in classroom functioning are evident several years after early childhood TBI and were associated with greater injury severity, neuropsychological weaknesses, and poorer academic performance. Children with impaired cognitive flexibility and fluid reasoning skills were at greatest risk for these difficulties and associated weaknesses in academic performance. Instructional interactions may be a potential target for intervention to promote academic progress in at-risk children. (PsycINFO Database Record

Observed parent behaviors as time-varying moderators of problem behaviors following traumatic brain injury in young children

Parent behaviors moderate the adverse consequences of pediatric traumatic brain injury (TBI); however, it is unknown how these moderating effects change over time. This study examined the moderating effect of observed parent behaviors over time since injury on the relation between TBI and behavioral outcomes. Participants included children, ages 3-7 years, hospitalized for moderate (n = 52) or severe (n = 20) TBI or orthopedic injury (OI; n = 95). Parent-child dyads were videotaped during structured task and free play conditions, and parents completed child behavior ratings. Linear mixed models using a lagged, time-varying moderator analysis examined the relationship of observed parent behaviors at the baseline, 6-month, and 12-month assessments to child behavior problems at 6 months, 12 months, and 18 months postinjury, after controlling for preinjury levels of child behavior problems. The effect of TBI on behavior was exacerbated by less favorable parent behaviors, and buffered by more favorable parent behaviors, in children with severe TBI over the first 12 months postinjury. By 18 months postinjury, however, the moderating effect of parent behaviors diminished, such that children with severe TBI showed more behavior problems relative to children with moderate TBI or OI regardless of parent behaviors or in response to parent behaviors that were initially protective. The results suggest that the moderating effects of the family environment are complex and likely vary in relation to both recovery and developmental factors, with potentially important implications for targets and timing of intervention. (PsycINFO Database Record

Applying Systems Biology Methodology To Identify Genetic Factors Possibly Associated with Recovery after Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality worldwide. It is linked with a number of medical, neurological, cognitive, and behavioral sequelae. The influence of genetic factors on the biology and related recovery after TBI is poorly understood. Studies that seek to elucidate the impact of genetic influences on neurorecovery after TBI will lead to better individualization of prognosis and inform development of novel treatments, which are considerably lacking. Current genetic studies related to TBI have focused on specific candidate genes. The objectives of this study were to use a system biology-based approach to identify biologic processes over-represented with genetic variants previously implicated in clinical outcomes after TBI and identify unique genes potentially related to recovery after TBI. After performing a systematic review to identify genes in the literature associated with clinical outcomes, we used the genes identified to perform a systems biology-based integrative computational analysis to ascertain the interactions between molecular components and to develop models for regulation and function of genes involved in TBI recovery. The analysis identified over-representation of genetic variants primarily in two biologic processes: response to injury (cell proliferation, cell death, inflammatory response, and cellular metabolism) and neurocognitive and behavioral reserve (brain development, cognition, and behavior). Overall, this study demonstrates the use of a systems biology-based approach to identify unique/novel genes or sets of genes important to the recovery process. Findings from this systems biology-based approach provide additional insight into the potential impact of genetic variants on the underlying complex biological processes important to TBI recovery and may inform the development of empirical genetic-related studies for TBI. Future studies that combine systems biology methodology and genomic, proteomic, and epigenetic approaches are needed in TBI.

Influence of Dopamine-Related Genes on Neurobehavioral Recovery after Traumatic Brain Injury during Early Childhood

The present study examined the association of dopamine-related genes with short- and long-term neurobehavioral recovery, as well as neurobehavioral recovery trajectories over time, in children who had sustained early childhood traumatic brain injuries (TBI) relative to children who had sustained orthopedic injuries (OI). Participants were recruited from a prospective, longitudinal study evaluating outcomes of children who sustained a TBI (n = 68) or OI (n = 72) between the ages of 3 and 7 years. Parents completed ratings of child executive function and behavior at the immediate post-acute period (0-3 months after injury); 6, 12, and 18 months after injury; and an average of 3.5 and 7 years after injury. Thirty-two single nucleotide polymorphisms (SNPs) in dopamine-related genes (dopamine receptor D2 [DRD2], solute carrier family 6 member 3 [SLC6A3], solute carrier family 18 member A2 [SLC18A2], catechol-o-methyltransferase [COMT], and ankyrin repeat and kinase domain containing 1 [ANKK1]) were examined in association with short- and long-term executive function and behavioral adjustment, as well as their trajectories over time. After controlling for premorbid child functioning, genetic variation within the SLC6A3 (rs464049 and rs460000) gene was differentially associated with neurobehavioral recovery trajectories over time following TBI relative to OI, with rs464049 surviving multiple testing corrections. In addition, genetic variation within the ANKK1 (rs1800497 and rs2734849) and SLC6A3 (rs464049, rs460000, and rs1042098) genes was differentially associated with short- and long-term neurobehavioral recovery following TBI, with rs460000 and rs464049 surviving multiple testing corrections. The findings provide preliminary evidence that genetic variation in genes involved in DRD2 expression and density (ANKK1) and dopamine transport (SLC6A3) plays a role in neurobehavioral recovery following pediatric TBI.

Changes in Structural Connectivity Following a Cognitive Intervention in Children With Traumatic Brain Injury

OBJECTIVE

Structural connectivity analysis based on graph theory and diffusion tensor imaging tractography is a novel method that quantifies the topological characteristics in the brain network. This study aimed to examine structural connectivity changes following the Attention Intervention and Management (AIM) program designed to improve attention and executive function (EF) in children with traumatic brain injury (TBI).

METHODS

Seventeen children with complicated mild to severe TBI (13.66 ± 2.68 years; >12 months postinjury) completed magnetic resonance imaging (MRI) and neurobehavioral measures at time 1, 10 of whom completed AIM and assessment at time 2. Eleven matched healthy comparison (HC) children (13.37 ± 2.08 years) completed MRI and neurobehavioral assessment at both time points, but did not complete AIM. Network characteristics were analyzed to quantify the structural connectivity before and after the intervention.

RESULTS

Mixed model analyses showed that small-worldness was significantly higher in the TBI group than the HC group at time 1, and both small-worldness and normalized clustering coefficient decreased significantly at time 2 in the TBI group whereas the HC group remained relatively unchanged. Reductions in mean local efficiency were significantly correlated with improvements in verbal inhibition and both parent- and child-reported EF. Increased normalized characteristic path length was significantly correlated with improved sustained attention.

CONCLUSION

The results provide preliminary evidence suggesting that graph theoretical analysis may be a sensitive tool in pediatric TBI for detecting ( a) abnormalities of structural connectivity in brain network and ( b) structural neuroplasticity associated with neurobehavioral improvement following a short-term intervention for attention and EF.

Long-Term Neuropsychological Profiles and Their Role as Mediators of Adaptive Functioning after Traumatic Brain Injury in Early Childhood

The objectives of the study were to characterize long-term neuropsychological outcomes following traumatic brain injury (TBI) sustained during early childhood, and determine whether identified neuropsychological impairments mediated the effect of TBI on long-term adaptive functioning. Participants included 16 children with severe TBI, 42 children with moderate TBI, and 72 children with orthopedic injuries (OI) sustained between ages 3 and 7 years. Children completed neuropsychological tests and caregivers completed a structured interview of child adaptive functioning at 6.9 (±1.10) years post-injury. Profile analysis and multiple mediator modeling were employed. Children with severe TBI demonstrated poorer fluid reasoning and inhibitory control than both children with moderate TBI and OI, as well as slower processing speed than the OI group. Both fluid reasoning and processing speed were significant independent mediators of the effect of severe TBI on adaptive functioning. No neuropsychological measure significantly mediated the effect of moderate TBI on adaptive functioning. Children sustaining early severe TBI demonstrate persisting neuropsychological impairments into adolescence and young adulthood. The impact of severe TBI on children's long-term adaptive functioning is mediated in part by its effects on fluid reasoning and processing speed.

Attention in spina bifida myelomeningocele: Relations with brain volume and integrity

This study investigated the relations of tectal volume and superior parietal cortex, as well as alterations in tectocortical white matter connectivity, with the orienting and executive control attention networks in individuals with spina bifida myelomeningocele (SBM). Probabilistic diffusion tractography and quantification of tectal and superior parietal cortical volume were performed on 74 individuals aged 8–29 with SBM and a history of hydrocephalus. Behavioral assessments measured posterior (covert orienting) and anterior (conflict resolution, attentional control) attention network functions. Reduced tectal volume was associated with slower covert orienting; reduced superior parietal cortical volume was associated with slower conflict resolution; and increased axial diffusivity and radial diffusivity along both frontal and parietal tectocortical pathways were associated with reduced attentional control. Results suggest that components of both the orienting and executive control attention networks are impaired in SBM. Neuroanatomical disruption to the orienting network appears more robust and a direct consequence of characteristic midbrain dysmorphology; whereas, executive control difficulties may emerge from parietal cortical anomalies and reduced frontal and parietal cortical–subcortical white matter pathways susceptible to the pathophysiological effects of congenital hydrocephalus.

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We use robust correlations to model structure–function relations.

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We use a large sample of individuals with spina bifida myelomeningocele.

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Reduced tectal volume is associated with slower covert orienting.

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Reduced superior parietal cortical volume is associated with slower conflict resolution.

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Tectocortical pathways are associated with reduced attentional control.

Prospective and episodic memory in relation to hippocampal volume in adults with spina bifida myelomeningocele

The present study examined prospective and episodic memory in relation to age, functional independence, and hippocampal volume in younger to middle-aged adults with spina bifida myelomeningocele (SBM) and typically developing (TD) adults. Prospective and episodic memory, as well as hippocampal volume, was reduced in adults with SBM relative to TD adults. Neither memory performance nor hippocampal volume showed greater decrements in older adults. Lower hippocampal volume was associated with reduced prospective memory in adults with SBM, and this relation was specific to the hippocampus and not to a contrast structure, the amygdala. Prospective memory mediated the relation between hippocampal volume and functional independence in adults with SBM. The results add to emerging evidence for reduced memory function in adults with SBM and provide quantitative evidence for compromised hippocampal macrostructure as a neural correlate of reduced memory in this population.