Introduction: Mild traumatic brain injury (mTBI) is a serious public health issue and as much as one third of mTBI patients could be affected by persistent post-concussion symptoms (PPCS) three months after their injury. Even though a significant proportion of all mTBIs are sports-related (SR), little is known on the recovery process of SR mTBI patients and the potential differences between SR mTBI and patients who suffered non-sports-related mTBI. The objective of this study was to describe the evolution of PPCS among patients who sustained a SR mTBI compared to those who sustained non sport-related mTBI. Methods: This Canadian multicenter prospective cohort study included patients aged ≥ 14 who had a documented mTBI that occurred within 24 hours of Emergency Department (ED) visit, with a Glasgow Coma Scale score of 13-15. Patients who were hospitalized following their ED visit or unable to consent were excluded. Clinical and sociodemographic information was collected during the initial ED visit. Three follow-up phone interviews were conducted by a research nurse at 7, 30 and 90 days post-injury to assess symptom evolution using the validated Rivermead Post-concussion Symptoms Questionnaire (RPQ). Adjusted risk ratios (RR) were calculated to demonstrate the impact of the mechanism of injury (sports vs non-sports) on the presence and severity of PPCS. Results: A total of 1676 mTBI patients were included, 358 (21.4%) of which sustained a SR mTBI. At 90 days post-injury, patients who suffered a SR mTBI seemed to be significantly less affected by fatigue (RR: 0.70 (95% CI: 0.50-0.97)) and irritability (RR: 0.60 (95% CI: 0.38-0.94)). However, no difference was observed between the two groups regarding each other symptom evaluated in the RPQ. Moreover, the proportion of patients with three symptoms or more, a score ≥21 on the RPQ and those who did return to their normal activities were also comparable. Conclusion: Although persistent post-concussion symptoms are slightly different depending on the mechanism of trauma, our results show that patients who sustained SR-mTBI could be at lower risk of experiencing some types of symptoms 90 days post-injury, in particular, fatigue and irritability.

Objective: To identify the systems available to sub-classify mild traumatic brain injury (TBI) and to determine their utility in predicting 1-year outcome.

Methods: A systematic review to identify mild-TBI sub-classification systems was conducted until March 2016. The identified systems were applied to a cohort of N = 290 adults who had experienced a mild-TBI, and who had been assessed for post-concussion symptoms 1-year post injury. ANOVAs and regression models were used to determine whether each sub-classification system could distinguish between outcomes and to explore their contribution to explaining variance in post-concussion symptoms 1-year post injury.

Results: Nineteen sub-classification systems for mild-TBI met the inclusion criteria for this review. The Saal (1991) classification system significantly differentiated the experience of post-concussion symptoms in our cohort 1-year post injury (F = 2.39, p = 0.05). However, the findings did not remain significant following correction for multiple comparisons and inclusion of socio-demographic and contextual factors in the regression model.

Conclusions: Current sub-classification systems fail to explain much of the variance in post-concussion symptoms 1 year following mild-TBI. Further research is needed to identify the factors (including socio-demographic and contextual factors) to determine, who may be at risk of developing persistent post-concussion symptoms.

Objectives: The aim of this study was to demonstrate the utility of an evidence-based assessment (EBA) model to establish a multimodal set of tools for identifying students at risk for perceived post-injury academic problems. Methods: Participants included 142 students diagnosed with concussion (age: M=14.95; SD=1.80; 59% male), evaluated within 4 weeks of injury (median=16 days). Demographics, pre-injury history, self- and parent-report measures assessing symptom severity and executive functions, and cognitive test performance were examined as predictors of self-reported post-injury academic problems. Results: Latent class analysis categorized participants into “high” (44%) and “low” (56%) levels of self-reported academic problems. Receiver operating characteristic analyses revealed significant discriminative validity for self- and parent-reported symptom severity and executive dysfunction and self-reported exertional response for identifying students reporting low versus high academic problems. Parent-reported symptom ratings [area under the receiver operating characteristic curve (AUC)=.79] and executive dysfunction (AUC=.74), and self-reported ratings of executive dysfunction (AUC=.84), symptoms (AUC=.80), and exertional response (AUC=.70) each classified students significantly better than chance (ps<.001). Hierarchical logistic regression indicated that, of the above, self-reported symptoms and executive dysfunction accounted for the most variance in the prediction of self-reported academic problems. Conclusions: Post-concussion symptom severity and executive dysfunction significantly predict perceived post-injury academic problems. EBA modeling identified the strongest set of predictors of academic challenges, offering an important perspective in the management of concussion by applying traditional strengths of neuropsychological assessment to clinical decision making. (JINS, 2016, 22, 1038–1049)

Exploring the relationship between genetic factors and outcome following brain injury has received increased attention in recent years. However, few studies have evaluated the influence of genes on specific sequelae of concussion. The purpose of this study was to determine how the ϵ4 allele of the apolipoprotein E (APOE) gene influences symptom expression following sports-related concussion. Participants included 42 collegiate athletes who underwent neuropsychological testing, including completion of the Post-Concussion Symptom Scale (PCSS), within 3 months after sustaining a concussion (73.8% were evaluated within 1 week). Athletes provided buccal samples that were analyzed to determine the make-up of their APOE genotype. Dependent variables included a total symptom score and four symptom clusters derived from the PCSS. Mann-Whitney U tests showed higher scores reported by athletes with the ϵ4 allele compared to those without it on the total symptom score and the physical and cognitive symptom clusters. Furthermore, logistic regression showed that the ϵ4 allele independently predicted those athletes who reported physical and cognitive symptoms following concussion. These findings illustrate that ϵ4+ athletes report greater symptomatology post-concussion than ϵ4- athletes, suggesting that the ϵ4 genotype may confer risk for poorer post-concussion outcome. (JINS, 2016, 22, 89–94)

Background: Persistent post-concussion symptoms (PCS) are associated with adverse psychosocial outcomes, including psychological distress and poorer health-related quality of life (HRQOL). Research has found that the occurrence of persistent PCS can be lowered via paper-based psychoeducation. Unfortunately, these resources have mostly been evaluated in adult populations. Studies in children have failed to address the role of parents in the development and maintenance of PCS, and unfortunately fail to reach a large proportion of the mild traumatic brain injury (mTBI) population who do not attend hospital. This study aimed to describe and evaluate a parent information booklet and child information website, for the prevention of paediatric PCS.

Methods: Children with uncomplicated mTBI were randomly assigned to either the Intervention (n = 29) or Usual Care condition (n = 20). Families completed pre-treatment, post-treatment (3 month) and follow-up (6 month) assessments of children's PCS, cognitive and psychosocial functioning, and parent's psychosocial functioning. Families also provided feedback on the psychoeducation resources.

Results: The Intervention programme, compared to Usual Care, was not associated with significant reductions in children's PCS or HRQOL, parent or child psychological distress, or parent or child knowledge of mTBI.

Conclusions: Psychoeducation resources do not appear to be superior to usual care in promotion of both child and parent psychosocial outcomes following mTBI.

The utility of injury characteristics for predicting the severity of post-concussion outcomes remains equivocal. The purpose of this meta-analysis was to quantify the predictive relationship between these variables to inform classification of acute injury severity. Thirty-one empirical samples of concussed athletes, for which rates of loss of consciousness and/or amnesia were reported, were included in a meta-analysis evaluating acute outcomes following sports-related concussion. Outcome measures of interest were neuropsychological tests first administered 1–10 days post-injury. Loss of consciousness and anterograde amnesia significantly predicted more severe neuropsychological deficits within 10 days of concussion in studies using pre-injury baseline, but not control group, comparisons. Retrograde amnesia significantly predicted acute neuropsychological dysfunction (d = -1.03) irrespective of comparison group. Although small sample sizes require conservative interpretation and future replication, the evidence suggests that retrograde amnesia, rather than loss of consciousness, may be used to classify the acute severity of concussion. (JINS, 2014, 20, 81–87)

This study examines rates of reporting of new or worse post-traumatic symptoms for patients with a broad range of injury severity at 1 month and 1 year after traumatic brain injury (TBI), as compared with those whose injury spared the head, and assesses variables related to symptom reporting at 1 year post-injury. Seven hundred thirty two TBI subjects and 120 general trauma comparison (TC) subjects provided new or worse symptom information at 1 month and/or 1 year post-injury. Symptom reporting at 1 year post-injury was compared in subgroups based on basic demographics, preexisting conditions, and severity of brain injury. The TBI group reported significantly more symptoms at 1 month and 1 year after injury than TCs (each p < .001). Although symptom endorsement declined from 1 month to 1 year, 53% of people with TBI and 24% of TC continued to report 3 or more symptoms at 1 year post-injury. Symptom reporting in the TBI group was significantly related to age, gender, preinjury alcohol abuse, pre-injury psychiatric history, and severity of TBI. Symptom reporting is common following a traumatic injury and continues to be experienced by a substantial number of TBI subjects of all severity levels at 1 year post-injury. (JINS, 2010, 16, 401–411.)