Paul Comper

A systematic review of treatments for mild traumatic brain injury.

Objectives: To assess the effectiveness of interventions for mild traumatic brain injury (MTBI) in adults as found in the literature. Research design: Systematic review of the literature. Methods: Six electronic databases and 18 journals within the brain injury field were manually searched between the years 1980–2003. References from articles were scanned for further literature. Studies that met broad inclusion criteria were subjected to a formal test of relevance. Those found to be relevant were qualitatively tested for their methodological soundness. Results: One thousand and fifty-five studies were initially identified and 163 were assessed using the relevance tool, yielding 20 studies for review. Four categories of interventions were identified: Pharmacotherapy, Cognitive Rehabilitation, Patient Education and Other. The majority of studies were weak, however there is evidence to support the effectiveness of patient education interventions. Conclusions: There are few rigorous studies evaluating treatment of MTBI. Limitations of the current literature are presented.

A systematic review of the rehabilitation of moderate to severe acquired brain injuries

Objective: To conduct a systematic review of the rehabilitation literature of moderate to severe acquired brain injuries (ABI) from traumatic and non-traumatic causes. Methods: A review of the literature was conducted for studies looking at interventions in ABI rehabilitation. The methodological quality of each study was determined using the Downs and Black scale for randomized controlled trials (RCTs) and non-RCTs as well as the Physiotherapy Evidence Database (PEDro) scale for RCTs only. Results: Almost 14 000 references were screened from which 1312 abstracts were selected. A total of 303 articles were chosen for careful review of which 275 were found to be interventional studies but only 76 of these interventional studies were RCTs. From this, 5 levels of evidence were determined with 177 conclusions drawn; however of the 177 conclusions only 7 were supported by two or more RCTs and 41 were supported by one RCT. Conclusion: Only 28% of the interventional studies were RCTs. Over half of the 275 interventional studies were single group interventions, pointing to the need for studies of improved methodological quality into ABI rehabilitation.

Emotional response to sport concussion compared to ACL injury

Primary objectives: To ascertain and compare the nature of emotional response of athletes to concussion and to anterior cruciate ligament (ACL) injury. Research design: Pre-injury, post-injury and longitudinal emotional functioning of athletes with concussion (n = 16), athletes with ACL injuries (n = 7) and uninjured athletes (n = 28) were compared in a prospective repeated-measures design. Methods and procedures: Participants completed the short version of the Profile of Mood States (POMS). ANOVAs and trend analysis were used to examine between and within group differences across time on two sub-scales, Total Mood Disturbance and Depression. Main outcomes and results: Athletes with ACL injury reported higher levels of depression for a longer duration than athletes with concussion. Relative to un-injured controls, athletes with concussion reported significant changes in Total Mood Disturbance and Depression post-injury, whereas athletes with ACL injuries reported significant changes in Depression scores only. Different patterns of post-injury emotional disturbance for the injured groups were observed by trend analyses. Conclusions: Concussed athletes do not report as much emotional disturbance as athletes with ACL injuries. Differential patterns of emotional disturbance were detected between injured groups. The authors recommended that clinical protocols and educational programmes address emotional sequelae associated with sport concussion and ACL injury.

Differential emotional responses of varsity athletes to concussion and musculoskeletal injuries.

Objective: To determine if athletes with concussion and those with minor musculoskeletal injuries experienced differential emotional response to injury. Design: A prospective longitudinal cohort study. Setting: University of Toronto, Ontario, Canada. Participants: Thirty-four injured athletes from Canadian Interuniversity Sport (CIS) and 19 healthy, physically active undergraduate students participated in the study. Intervention: All participants completed the Profile of Mood States (POMS; short version) on 3 nonconsecutive days during a 2-week period after a baseline test. Main Outcome Measures: Emotional responses were assessed using the POMS. The 7 main outcome measures assessed by POMS were tension, depression, anger, vigor, fatigue, confusion, and total mood disturbance. Results: After injury, concussion produced an emotional profile characterized by significantly elevated fatigue and decreased vigor. In contrast, athletes with musculoskeletal injuries displayed a significant increase in anger that resolved to a pre-injury level within 2 weeks. Conclusions: The results revealed that both injured groups experienced emotional disturbance after injury. More importantly, the findings strongly suggest that the emotional reaction after concussion is different from that of musculoskeletal injury. Therefore, we concluded that assessing emotional reactions to concussion is particularly important and recommend that sports medicine professionals assess and monitor emotional functioning as well as somatic complaints and neurocognitive changes during recovery.

Does the Apolipoprotein e4 Allele Predispose Varsity Athletes to Concussion? A Prospective Cohort Study

Objective:To determine the association between the apolipoprotein ϵ4 allele and concussion. We hypothesized that apolipoprotein ϵ4 carriers may be more likely to sustain a concussion. Design:Prospective cohort study. Setting:University of Toronto varsity athletics. Participants:Included 318 of 822 collegiate student athletes who participated in University of Toronto varsity sports from September 2002 to April 2006. Assessment of Risk Factors:The presence of apolipoprotein ϵ4 was described dichotomously after genotyping blood samples collected from participants. Main Outcome Measurements:Concussions were identified by sport-medicine professionals present on the sidelines using on-field assessment forms. All concussion diagnoses were verified by a sports medicine physician. Survival analysis was used to determine the association between apolipoprotein ϵ4 and first concussion. Results:The unadjusted hazard ratio for concussion in the apolipoprotein ϵ4 carriers was 1.18 (95% CI: 0.52, 2.69) compared to noncarriers. Adjustment for sex, weight, height, and team type resulted in a hazard ratio of 1.06 (95% CI: 0.41, 2.72), indicating little effect from confounding factors. Conclusions:There is no important association between carrying the apolipoprotein ϵ4 allele and sustaining a concussion. At this time, we do not recommend preseason genetic testing for varsity athletes as a mechanism for targeting prevention strategies.

Advances in neuropsychological assessment of sport-related concussion

Objective To critically review the literature from the past 12 years regarding the following key issues in sports-related neuropsychological assessment: (1) the advantages and disadvantages of different neuropsychological assessment modalities; (2) the evidence for and against the current paradigm of baseline/postinjury testing; (3) the role of psychological factors in the evaluation and management of concussion; (4) advances in the neuropsychological assessment of children; (5) multi-modal assessment paradigms; (6) the role of the neuropsychologist as part of the sports healthcare team and (6) the appropriate administration and interpretation of neuropsychological tests. Design Targeted computerised literature review (MEDLINE, PubMed, CINAHL and PsychInfo) from 2000 to the present using key words: neuropsychological, neurocognitive, assessment, testing, concussion and sports. Results More than 2600 articles were identified using key word searches of the databases, including many duplicates. Several books were also reviewed. The articles were pared down for review if they specifically addressed the key areas noted above. Conclusions Traditional and computerised neuropsychological tests are useful in the evaluation and management of concussion. Brief cognitive evaluation tools are not substitutes for formal neuropsychological assessment. At present, there is insufficient evidence to recommend the widespread routine use of baseline neuropsychological testing. Although scant, research suggests that psychological factors may complicate and prolong recovery from concussion in some athletes. Age-appropriate symptom scales for children have been developed but research into age-appropriate tests of cognitive functions lags behind. Neuropsychologists are uniquely qualified to interpret neuropsychological tests and can play an important role within the context of a multifaceted-multimodal approach to manage sports-related concussions.

A systematic video analysis of National Hockey League (NHL) concussions, part I: who, when, where and what?

Background Although there is a growing understanding of the consequences of concussions in hockey, very little is known about the precipitating factors associated with this type of injury. Aim To describe player characteristics and situational factors associated with concussions in the National Hockey League (NHL). Methods Case series of medically diagnosed concussions for regular season games over a 3.5-year period during the 2006–2010 seasons using an inclusive cohort of professional hockey players. Digital video records were coded and analysed using the Heads Up Checklist. Results Of 197 medically diagnosed concussions, 88% involved contact with an opponent. Forwards accounted for more concussions than expected compared with on-ice proportional representation (95% CI 60 to 73; p=0.04). Significantly more concussions occurred in the first period (47%) compared with the second and third periods (p=0.047), with the majority of concussions occurring in the defensive zone (45%). Approximately 47% of the concussions occurred in open ice, 53% occurred in the perimeter. Finally, 37% of the concussions involved injured players’ heads contacting the boards or glass. Conclusions This study describes several specific factors associated with concussions in the NHL, including period of the game, player position, body size, and specific locations on the ice and particular situations based on a players position.

Concussions and heading in soccer: a review of the evidence of incidence, mechanisms, biomarkers and neurocognitive outcomes.

Abstract Background: Soccer is currently the most popular and fastest-growing sport worldwide. Similar to many sports, soccer carries an inherent risk of injury, including concussion. Soccer is also unique in the use of ‘heading’. The present paper provides a comprehensive review of the research examining the incidence, mechanisms, biomarkers of injury and neurocognitive outcomes of concussions and heading in soccer. Methods: Seven databases were searched for articles from 1806 to 24 May 2013. Articles obtained by the electronic search were reviewed for relevance, with 229 selected for review. Ultimately, 49 articles met criteria for inclusion in the present review. Results: Female soccer players have a higher incidence of concussions than males. The most frequent injury mechanism is player-to-player contact for both genders. Few studies examined the effects of concussion in soccer players; however, neurocognitive outcomes were similar to those reported in the larger sport concussion literature, while the effect of heading is less clear. Conclusion: Despite variation in research designs and study characteristics, the outcomes of concussions in soccer align with the greater concussion literature. This review makes recommendations for future research to increase standardization of research for improved understanding of concussions in soccer as well as the effects of heading.

The role of apolipoprotein E episilon (ɛ)-4 allele on outcome following traumatic brain injury: A systematic review

Abstract Background: The apolipoprotein E gene (APOE) has emerged as a candidate for prognosticating traumatic brain injury (TBI) recovery, with APOEɛ4 identified as a susceptibility marker for poor outcome, despite large discrepancy in its reported influence post-TBI. Methods: A systematic review was conducted, including all primary articles investigating the role of APOEɛ4 on TBI outcome. A total of 65 studies were included, including 24 predominantly investigating mild (mTBI), seven moderate (modTBI) and 33 severe (sTBI); severity was not reported in one study. Results: In mTBI studies, the association between APOEɛ4 and post-TBI outcome was concluded as non-contributory in 14 studies (58.3%), hazardous in nine (37.5%) and protective in one (4.2%). In sTBI studies, the role of APOEɛ4 was hazardous in 21 (63.6%), non-contributory in nine (27.3%) and protective in three (9.1%). Of the seven studies investigating dementia outcomes, four observed a hazardous association with APOEɛ4, while three reported no association. Six studies examined Alzheimer’s dementia pathology, of which three reported a hazardous influence of APOEɛ4. Conclusions: The influence of APOEɛ4 on neuropsychological testing, functional outcome and in paediatric populations was incongruous. This review supports the majority of research indicating APOEɛ4 adversely influences recovery following TBI, particularly with respect to dementia-related outcomes and outcomes following sTBI.

1 year test-retest reliability of ImPACT in professional ice hockey players.

The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery is widely used to assess neurocognitive outcomes following sports-related concussion. The purpose of this study was to examine the 1 year test–retest reliability of ImPACT in a multilingual sample of professional hockey players. A total of 305 professional hockey players were tested 1 year apart using ImPACT. Reliable change confidence intervals were calculated and test–retest reliability was measured using Pearson and Intraclass correlation coefficients. Results indicated that the 1-year test–retest reliabilities for the Visual Motor and Reaction Time Composites ranged from low to high (.52 to .81). In contrast, 1-year test–retest reliabilities for the Verbal and Visual Memory Composites were low (.22 to .58). The 1-year test–retest results provided mixed support for the use of Visual Motor and Reaction Time Composites in select samples; in contrast, the Verbal and Visual Memory Composites may not be sensitive to clinical change.