Early mild traumatic brain injury (mTBI or concussion sustained between 0 and 5 years old) can lead to post-concussive symptoms, behavioral changes, and cognitive difficulties. Although school-age children (6–17 years old) experience similar consequences, severe neuropsychological deficits are not common, and the majority have no persisting symptoms after one month. Thus, there may be value in focusing on what characterizes optimal functioning (or wellness) after mTBI, but this has not been explored in young children. This study documents the evolution and predictors of optimal functioning after early mTBI.

Participants were 190 children aged 18 – 60 months with mTBI (n = 69), orthopedic injury (OI; n = 50), or typical development (TDC; n = 71). Optimal functioning was defined as: (1) no clinically significant behavioral problems; (2) no cognitive difficulties; (3) no persisting post-concussive symptoms; (4) average quality of life or better. Predictors related to sociodemographic, injury, child, and caregiver characteristics included number of acute symptoms, child sex, age, temperament, maternal education, parent-child attachment and interaction quality, and parenting stress.

Fewer children with mTBI had optimal functioning over 6 and 18-months post-injury compared to those with OI and TDC. Higher parent-child interaction quality and lower child negative affectivity temperament independently predicted optimal functioning.

Children who sustain early mTBI are less likely to exhibit optimal functioning than their peers in the long-term. Parent-child interaction quality could be a potential intervention target for promoting optimal function.

Symptoms and cognition are both utilized as indicators of recovery following pediatric concussion, yet their interrelationship is not well understood. This study aimed to investigate: 1) the association of post-concussion symptom burden and cognitive outcomes (processing speed and executive functioning [EF]) at 4 and 12 weeks after pediatric concussion, and 2) the moderating effect of sex on this association.

This prospective, multicenter cohort study included participants aged 5.00–17.99 years with acute concussion presenting to four Emergency Departments of the Pediatric Emergency Research Canada network. Five processing speed and EF tasks and the Post-Concussion Symptom Inventory (PCSI; symptom burden, defined as the difference between post-injury and retrospective [pre-injury] scores) were administered at 4 and 12 weeks post-concussion. Generalized least squares models were conducted with task performances as dependent variables and PCSI and PCSI*sex interaction as the main predictors, with important pre-injury demographic and injury characteristics as covariates.

311 children (65.0% males; median age = 11.92 [IQR = 9.14–14.21 years]) were included in the analysis. After adjusting for covariates, higher symptom burden was associated with lower Backward Digit Span (χ2 = 9.85, p = .043) and Verbal Fluency scores (χ2 = 10.48, p = .033) across time points; these associations were not moderated by sex, ps ≥ .20. Symptom burden was not associated with performance on the Coding, Continuous Performance Test, and Color-Word Interference scores, ps ≥ .17.

Higher symptom burden is associated with lower working memory and cognitive flexibility following pediatric concussion, yet these associations were not moderated by sex. Findings may inform concussion management by emphasizing the importance of multifaceted assessments of EF.

Despite a well-established link between childhood traumatic brain injury (TBI) and elevated secondary attention-deficit/hyperactivity disorder (s-ADHD) symptomology, the neurostructural correlates of these symptoms are largely unknown. Based on the influential ‘triple-network model’ of ADHD, this prospective longitudinal investigation aimed to (i) assess the effect of childhood TBI on brain morphometry of higher-order cognitive networks proposed to play a key role in ADHD pathophysiology, including the default-mode network (DMN), salience network (SN) and central executive network (CEN); and (ii) assess the independent prognostic value of DMN, SN and CEN morphometry in predicting s-ADHD symptom severity after childhood TBI.

The study sample comprised 155 participants, including 112 children with medically confirmed mild-severe TBI ascertained from consecutive hospital admissions, and 43 typically developing (TD) children matched for age, sex and socio-economic status. High-resolution structural brain magnetic resonance imaging (MRI) sequences were acquired sub-acutely in a subset of 103 children with TBI and 34 TD children. Parents completed well-validated measures of ADHD symptom severity at 12-months post injury.

Relative to TD children and those with milder levels of TBI severity (mild, complicated mild, moderate), children with severe TBI showed altered brain morphometry within large-scale, higher-order cognitive networks, including significantly diminished grey matter volumes within the DMN, SN and CEN. When compared with the TD group, the TBI group showed significantly higher ADHD symptomatology and higher rates of clinically elevated symptoms. In multivariable models adjusted for other well-established risk factors, altered DMN morphometry independently predicted higher s-ADHD symptomatology at 12-months post-injury, whilst SN and CEN morphometry were not significant independent predictors.

Our prospective study findings suggest that neurostructural alterations within higher-order cognitive circuitry may represent a prospective risk factor for s-ADHD symptomatology at 12-months post-injury in children with TBI. High-resolution structural brain MRI has potential to provide early prognostic biomarkers that may help early identification of high-risk children with TBI who are likely to benefit from early surveillance and preventive measures to optimise long-term neuropsychiatric outcomes.

To validate the two-factor structure (i.e., cognitive and somatic) of the Health and Behaviour Inventory (HBI), a widely used post-concussive symptom (PCS) rating scale, through factor analyses using bifactor and correlated factor models and by examining measurement invariance (MI).

PCS ratings were obtained from children aged 8–16.99 years, who presented to the emergency department with concussion (n = 565) or orthopedic injury (OI) (n = 289), and their parents, at 10-days, 3-months, and 6-months post-injury. Item-level HBI ratings were analyzed separately for parents and children using exploratory and confirmatory factor analyses (CFAs). Bifactor and correlated models were compared using various fit indices and tested for MI across time post-injury, raters (parent vs. child), and groups (concussion vs. OI).

CFAs showed good fit for both a three-factor bifactor model, consisting of a general factor with two subfactors (i.e., cognitive and somatic), and a correlated two-factor model with cognitive and somatic factors, at all time points for both raters. Some results suggested the possibility of a third factor involving fatigue. All models demonstrated strict invariance across raters and time. Group comparisons showed at least strong or strict invariance.

The findings support the two symptom dimensions measured by the HBI. The three-factor bifactor model showed the best fit, suggesting that ratings on the HBI also can be captured by a general factor. Both correlated and bifactor models showed substantial MI. The results provide further validation of the HBI, supporting its use in childhood concussion research and clinical practice.

Psychosocial deficits, such as emotional, behavioral and social problems, reflect the most common and disabling consequences of pediatric traumatic brain injury (TBI). Their causes and recovery likely differ from physical and cognitive skills, due to disruption to developing brain networks and the influence of the child's environment. Despite increasing recognition of post-injury behavioral and social problems, there exists a paucity of research regarding the incidence of social impairment, and factors predicting risk and resilience in the social domain over time since injury.

Using a prospective, longitudinal design, and a bio-psychosocial framework, we studied children with TBI (n = 107) at baseline (pre-injury function), 6 months, 1 and 2-years post-injury. We assessed intellectual ability, attention/executive function, social cognition, social communication and socio-emotional function. Children underwent structural magnetic resonance imaging (MRI) at 2–8 weeks post-injury. Parents rated their child's socio-emotional function and their own mental health, family function and perceived burden.

We distinguished five social recovery profiles, characterized by a complex interplay between environment and pre- and post-TBI factors, with injury factors playing a lesser role. Resilience in social competence was linked to intact family and parent function, intact pre-injury adaptive abilities, post-TBI cognition and social participation. Vulnerability in the social domain was related to poor pre- and post-injury adaptive abilities, greater behavioral concerns, and poorer pre- and post-injury parent health and family function.

We identified five distinct social recovery trajectories post-child-TBI, each characterized by a unique biopsychosocial profile, highlighting the importance of comprehensive social assessment and understanding of factors contributing to social impairment, to target resources and interventions to children at highest risk.

Ondansetron is increasingly administered to children suffering from concussion-associated nausea/vomiting. We examined the association between ondansetron administration and post-concussion symptoms in children at 1 week and 1 month following the concussion.

This was a secondary analysis of data collected prospectively in a cohort study conducted in nine pediatric emergency departments (EDs) (5P study). Participants were children ages between 5 and 17.99 years who sustained a concussion in the previous 48 hours. For the current study, only 5P participants who reported nausea and/or vomiting in the ED were eligible. The exposure of interest was ondansetron administration; the comparison group included all other participants. The primary outcome was an increase in at least three symptoms of the Post-Concussion Symptom Inventory score at 1 week and 1 month following trauma.

Among the 3,063 children included in the 5P study, 1805 (59%) reported nausea and provided data at 1 week and/or 1 month. Among them, 132 (7%) received ondansetron. Multivariable logistic regression adjusted for confounders did not show an association between ondansetron use and the risk of persistent post-concussion symptoms at 1 week (OR: 1.13 [95% CI: 0.86-1.49]), but it was associated with a higher risk at 1 month (OR: 1.33 [95% CI: 1.05-1.97]).

In children presenting to the ED with an acute concussion, ondansetron use was associated with a higher risk of persistent post-concussion symptoms at 1 month. Although this may be related to the limitations of the design, it highlights the importance of evaluating this association using a randomized clinical trial.

Pediatric traumatic brain injury (TBI) is a leading cause of long-term disability in children and adolescents worldwide. Amongst the wide array of consequences known to occur after pediatric TBI, behavioral impairments are among the most widespread and may particularly affect children who sustain injury early in the course of development. The aim of this study was to investigate the presence of internalizing and externalizing behavioral problems 6 months after preschool (i.e. 18–60 months old) mild TBI.

This work is part of a prospective, longitudinal cohort study of preschool TBI. Participants (N = 229) were recruited to one of three groups: children with mild TBI, typically developing children and orthopedic injured (OI) children. Mothers of children in all three groups completed the Child Behavior Checklist as a measure of behavioral outcomes 6-month post-injury. Demographics, injury-related characteristics, level of parental distress, and estimates of pre-injury behavioral problems were also documented.

The three groups did not differ on baseline characteristics (e.g. demographics and pre-injury behavioral problems for the mild TBI and OI groups) and level of parental distress. Mothers’ ratings of internalizing and externalizing behaviors were higher in the mild TBI group compared with the two control groups. Pre-injury behavioral problems and maternal distress were found to be significant predictors of outcome.

Our results show that even in its mildest form, preschool TBI may cause disruption to the immature brain serious enough to result in behavioral changes, which persist for several months post-injury.

Assess the feasibility of a study evaluating one dose of oral ondansetron to decrease post-concussion symptoms at one week and one month following concussion in children aged 8 to 17 years old.

This was a pilot study for a randomized, triple-blind controlled trial of one dose of either ondansetron or placebo performed in a tertiary care pediatric emergency department. Participants were children aged 8 to 17 years who sustained a concussion in the previous 24 hours and visited a single emergency department. The outcome of interest was an increase from pre-concussion baseline of at least 3 symptoms from the Post-Concussion Symptom Inventory, measured at one week and at one month following concussion. The primary outcome was to determine the proportion of children who completed the assessment at one week following the intervention. Secondary outcome was the proportion of children who completed the assessment at one month following the intervention. All children, care givers, and those assessing the outcomes were blinded to the group assignment.

Of the 218 children presenting with a concussion during the study period, we screened 108 and found 36/108 (33%) eligible to participate and 16/108 (14.8%) agreed to participate. All enrolled patients were compliant with the intervention and follow-up.

In our study population, approximately one-third of the screened concussion patients were eligible to participate and approximately one half of those eligible agreed to participate. Our study found that most enrolled patients preferred electronic follow-up; the noncompliance rate was minimal.