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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.

Pediatric neurocritical care survivorship is frequently accompanied by functional impairments. Lack of prognostic biomarkers is a barrier to early identification and management of impairment. We explored the association between blood biomarkers and functional impairment in children with acute acquired brain injury. This study is a secondary analysis of a randomized control trial evaluating early versus usual care rehabilitation in the pediatric intensive care unit (PICU). Forty-four children (17 [39%] female, median age 11 [interquartile range 6–13] years) with acute acquired brain injury admitted to the PICU were studied. A single center obtained serum samples on admission days 0, 1, 3, 5, and the day closest to hospital discharge. Biomarkers relevant to brain injury (neuron specific enolase [NSE], S100b), inflammation (interleukin [IL-6], C-reactive protein), and regeneration (brain-derived neurotrophic factor [BDNF], vascular endothelial growth factor [VEGF]) were collected. Biomarkers were analyzed using a Luminex® bioassay. Functional status scale (FSS) scores were abstracted from the medical record. New functional impairment was defined as a (worse) FSS score at hospital discharge compared to pre-PICU (baseline). Individual biomarker fluorescence index (FI) values for each sample collection day were correlated with new functional impairment using Spearman rank correlation coefficient (ρ). Trends in repeated measures of biomarker FI over time were explored graphically, and the association between repeated measures of biomarker FI and new functional impairment was analyzed using covariate adjusted linear mixed-effect models. Functional impairment was inversely correlated with markers of regeneration and plasticity including BDNF at day 3 (ρ = − 0.404, p = .015), day 5 (ρ = − 0.549, p = 0.005) and hospital discharge (ρ = − 0.420, p = 0.026) and VEGF at day 1 (ρ = − 0.282, p = 0.008) and hospital discharge (ρ = − 0.378, p = 0.047), such that lower levels of both markers at each time point were associated with greater impairment. Similarly, repeated measures of BDNF and VEGF were inversely correlated with new functional impairment (B = − 0.001, p = 0.001 and B = − 0.001, p = 0.003, respectively). NSE, a biomarker of acute brain injury, showed a positive correlation between day 0 levels and new functional impairment (ρ = 0.320, p = 0.044). Blood-based biomarkers of regeneration and plasticity may hold prognostic utility for functional impairment among pediatric patients with neurocritical illness and warrant further investigation.

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.

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.

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.

s: Few feasibility, safety, and efficacy data exist regarding ICU-based rehabilitative services for children. We hypothesized that early protocolized assessment and therapy would be feasible and safe versus usual care in pediatric neurocritical care patients.Randomized controlled trial.Three tertiary care PICUs in the United States.Fifty-eight children between the ages of 3-17 years with new traumatic or nontraumatic brain insult and expected ICU admission greater than 48 hours.Early protocolized (consultation of physical therapy, occupational therapy, and speech and language therapy within 72 hr ICU admission, n = 26) or usual care (consultation per treating team, n = 32).Primary outcomes were consultation timing, treatment type, and frequency of deferrals and safety events. Secondary outcomes included patient and family functional and quality of life outcomes at 6 months. Comparing early protocolized (n = 26) and usual care groups (n = 32), physical therapy was consulted during the hospital admission in 26 of 26 versus 28 of 32 subjects (p = 0.062) on day 2.4 ± 0.8 versus 7.7 ± 4.8 (p = 0.001); occupational therapy in 26 of 26 versus 23 of 32 (p = 0.003), on day 2.3 ± 0.6 versus 6.9 ± 4.8 (p = 0.001); and speech and language therapy in 26 of 26 versus 17 of 32 (p = 0.011) on day 2.3 ± 0.7 versus 13.0 ± 10.8 (p = 0.026). More children in the early protocolized group had consults and treatments occur in the ICU versus ward for all three services (all p0.001). Eleven sessions were discontinued early: nine during physical therapy and two during occupational therapy, none impacting patient outcome. There were no group differences in functional or quality of life outcomes.A protocol for early personalized rehabilitation by physical therapy, occupational therapy, and speech and language therapy in pediatric neurocritical care patients could be safely implemented and led to more ICU-based treatment sessions, accelerating the temporal profile and changing composition of interventions versus usual care, but not altering the total dose of rehabilitation.

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).

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. Language: en

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.

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.

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.

OBJECTIVE: To test the effectiveness of the Attention Improvement and Management (AIM) program, a cognitive intervention for improving impairments in attention and executive functions (EFs) after pediatric traumatic brain injury (TBI). SETTING: Tertiary care children's hospital. PARTICIPANTS: A total of 13 children with complicated mild-to-severe TBI (average of 5 years postinjury) and 11 healthy comparison children aged 9 to 15 years completed the study. DESIGN: Open-label pilot study with a nontreated control group. MAIN MEASURES: Subtests from the Test of Everyday Attention-for Children (TEA-Ch) and the Delis-Kaplan Executive Function System (D-KEFS), the self- and parent-report from the Behavior Rating Inventory of Executive Function (BRIEF), and the Goal Attainment Scale (GAS). RESULTS: Relative to the healthy comparison group, children with TBI demonstrated significant improvement postintervention on a neuropsychological measure of sustained attention, as well as on parent-reported EFs. The majority of families also reported expected or more-than-expected personalized goal attainment. CONCLUSIONS: The study provides preliminary evidence for the effectiveness of AIM in improving parent-reported EFs and personalized real-world goal attainment in children with TBI. Language: en

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.

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.

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

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.

OBJECTIVES To examine catechol-O-methyltransferase (COMT) rs4680 genotypes as moderators of the effects of parenting style on postinjury changes in parent behavior ratings of executive dysfunction following moderate to severe early childhood traumatic brain injury. SETTING Research was conducted in an outpatient setting. PARTICIPANTS Participants included children admitted to hospital with moderate to severe traumatic brain injury (n = 55) or orthopedic injuries (n = 70) between ages 3 and 7 years. DESIGN Prospective cohort followed over 7 years postinjury. MAIN MEASURES Parenting Practices Questionnaire and the Behavior Rating Inventory of Executive Functioning obtained at baseline, 6, 12, and 18 months, and 3.5 and 6.8 years postinjury. DNA was collected from saliva samples, purified using the Oragene (DNA Genotek, Ottawa, Ontario, Canada) OG-500 self-collection tubes, and analyzed using TaqMan (Applied Biosystems, Thermo Fisher Scientific, Waltham, Massachusetts) assay protocols to identify the COMT rs4680 polymorphism. RESULTS Linear mixed models revealed a significant genotype × parenting style × time interaction (F = 5.72, P = .02), which suggested that the adverse effects of authoritarian parenting on postinjury development of executive functioning were buffered by the presence of the COMT AA genotype (lower enzyme activity, higher dopamine levels). There were no significant associations of executive functioning with the interaction between genotype and authoritative or permissive parenting ratings. CONCLUSION The lower activity COMT rs4680 genotype may buffer the negative effect of authoritarian parenting on long-term executive functioning following injury in early childhood. The findings provide preliminary evidence for associations of parenting style with executive dysfunction in children and for a complex interplay of genetic and environmental factors as contributors to decreases in these problems after traumatic injuries in children. Further investigation is warranted to understand the interplay among genetic and environmental factors related to recovery after traumatic brain injury in 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(c) 2016 APA, all rights reserved). Language: en

Objectives:To examine whether apolipoprotein e4 (APOE) status moderates the association of family environment with child functioning following early traumatic brain injury (TBI).Methods:Sixty-five children with moderate to severe TBI and 70 children with orthopedic injury (OI) completed assessments 6, 12, 18 months, and 3.5 and 6.8 years post injury. DNA was extracted from saliva samples and genotyped for APOE e4 status. Linear mixed models examined moderating effects of APOE e4 status on associations between two family environment factors (parenting style, home environment) and three child outcomes (executive functioning, behavioral adjustment, adaptive functioning).Results:Children with TBI who were carriers of the e4 allele showed poorer adaptive functioning relative to non-carriers with TBI and children with OI in the context of low authoritarianism. At high levels of authoritarianism, non-carriers with TBI showed the poorest adaptive functioning among groups. There were no main effects or interactions involving APOE and executive functioning or behavioral adjustment.Conclusions:The APOE e4 allele was detrimental for long-term adaptive functioning in the context of positive parenting, whereas in less optimal parenting contexts, being a non-carrier was detrimental. We provide preliminary evidence for an interaction of APOE e4 status and parenting style in predicting long-term outcomes following early TBI. (JINS, 2016,22, 859–864)