Consistency of Self-Reported Concussion History in Adolescent Athletes

Concussion history associated with adolescent psychological distress but not hazardous gambling: a cross-sectional study

BACKGROUND

Sustaining multiple concussions over one's lifetime may be associated with behavioral and mood changes beyond the acute phase of injury. The present cross-sectional study examined the relationship between concussion history, the incidence of current moderate-severe psychological distress, and lifetime adolescent hazardous gambling in high school students.

METHODS

Four-hundred fifty-nine high school students from southern Sweden (age: 16.81 ± 0.83, 58.2% male) completed a survey assessing concussion history (0,1,2…>8), psychological distress using the Kessler-6 scale, and lifetime hazardous gambling using the NODS-CLiP scale.

RESULTS

Participants who self-reported three or more concussions were more likely to endorse moderate-severe symptoms of psychological distress than those with no concussion history while controlling for covariates, OR = 2.71, 95% CI [1.19, 6.18]. In contrast, concussion history was not associated with hazardous gambling after controlling for confounding variables.

CONCLUSIONS

Self-reporting three or more concussions was associated with increased current psychological distress beyond the acute phase of injury among high school students. Adolescents who have sustained multiple concussions should undergo mental health evaluations beyond the acute phase of injury to identify and treat psychological distress, but probing for hazardous gambling may not be clinically relevant in this previously concussed adolescent population.

Cause of Concussion With Persisting Symptoms Is Associated With Long-Term Recovery and Symptom Type, Duration, and Number in a Longitudinal Cohort of 600 Patients

It is important for patients and clinicians to know the potential for recovery from concussion as soon as possible after injury, especially in patients who do not recover completely in the first month and have concussion with persisting concussion symptoms (C+PCS). We assessed the association between the causes of concussion and recovery from C+PCS in a consecutive retrospective and prospective cohort of 600 patients referred to the Canadian Concussion Center (CCC) at Toronto Western Hospital. Data were obtained from clinical records and follow-up questionnaires and not from a standardized database. A novel method was used to assess long-term recovery, and multi-variable Cox proportional hazards models were used to assess relationships between cause of concussion and time to recovery. We examined the subsequent recovery of patients who had not recovered after at least one month from the time of concussion. Patients were grouped into the following four causes: sports and recreation (S&R, n = 312, 52%); motor vehicle collisions (MVC, n = 103, 17%); falls (n = 100, 17%); and being struck by an object including violence (SBOV, n = 85, 14%). The MVC group had the highest percentage of females (75.7%), the oldest participants (median: 40.0 [interquartile range (IQR):30.5-49.0] years), the most symptoms (median:11.0 [IQR:8.5-15.0]), and the longest symptom duration (median: 28.0 [IQR:12.0-56.00] months). In contrast, the S&R group had the highest percentage of males (58.1%), the youngest participants (median:20.0 [IQR:17.0-30.0] years), the best recovery outcome, and shortest symptom duration (median:22.0 [IQR:8.0-49.5] months). Significant differences among the four causes included age (p < 0.001), sex (p < 0.001), number of previous concussions (p < 0.001), history of psychiatric disorders (p = 0.002), and migraine (p = 0.001). Recovery from concussion was categorized into three groups: (1) Complete Recovery occurred in only 60 (10%) patients with median time 8.0 (IQR:3.5-18.0) months and included 42 S&R, 7 MVC, 8 falls, and 3 SBOV; (2) Incomplete Recovery occurred in 408 (68.0%) patients with persisting median symptom time of 5.0 (IQR:2.0-12.0) months; and (3) Unknown Recovery occurred in 132 (22.0%) patients and was because of lack of follow-up. In summary, the cause of C+PCS was associated with the type, number, and duration of symptoms and time required for recovery, although all causes of C+PCS produced prolonged symptoms in a large percentage of patients, which emphasizes the importance of concussions as a public health concern necessitating improved prevention and treatment strategies.

Language Matters: Comparisons of Concussion Assessments Among English- and Spanish-Speaking Middle School Athletes

CONTEXT

The Child Sport Concussion Assessment Tool, fifth edition (Child SCAT5), is among the most widely used international pediatric concussion evaluation tools. However, the tool's English-only aspect may limit its use for patients who speak different languages. Prior researchers have suggested one's preferred language (ie, home language) could be associated with concussion assessments in adults, yet how this might affect pediatric athletes is not well understood.

OBJECTIVE

To compare baseline Child SCAT5 assessment outcomes between middle school athletes whose home language was Spanish and matched control athletes whose home language was English.

DESIGN

Case-control study.

SETTING

Middle school athletics.

PATIENTS OR OTHER PARTICIPANTS

Athletes self-reported their home language (ie, language spoken at home). Those indicating their home language was Spanish were individually matched to athletes who spoke English at home on age, sex, sport, school, and pertinent comorbidities (eg, concussion history). The final sample consisted of 144 athletes (Spanish home language = 72, English home language = 72).

MAIN OUTCOME MEASURE(S)

We used Mann-Whitney U tests to compare the Child SCAT5 component scores of the home language groups (ie, Spanish versus English).

RESULTS

Athletes in the Spanish home language group scored lower on the Standardized Assessment of Concussion-Child version (P < .01, r = -0.25), Immediate Memory (P < .01, r = -0.45), and total modified Balance Error Scoring System scores (P < .01, r = -0.25) than the English home language group.

CONCLUSIONS

Matched athletes whose home language was Spanish versus English scored differently on baseline Child SCAT5 assessment components. Those with the home language of Spanish scored lower on cognitive and balance tasks than those whose home language was English. These findings may serve as a rationale for the development of future concussion assessment tools to properly capture clinically relevant data regarding language differences among pediatric athletes.

Level of Agreement Between Child and Parent Reporting on the Child Sport Concussion Assessment Tool (SCAT5)

CONTEXT

The Child Sport Concussion Assessment Tool, fifth edition (SCAT5), remains the consensus instrument for concussion evaluation in youth athletes. Both child and parent are recommended to complete the athlete background and symptom reporting.

OBJECTIVE

To determine the level of agreement between child and parent medical history and symptom reporting and quantify their performance on the Child SCAT5 in male football athletes.

DESIGN

Cross-sectional study.

SETTING

National Collegiate Athletic Association Division I college football facility.

PATIENTS OR OTHER PARTICIPANTS

A total of 157 youth male football athletes (age = 10.7 ± 1.3 years) participating in a university-sanctioned youth football camp and their parent or legal guardian.

MAIN OUTCOME MEASURE(S)

Youth athletes and their parent completed the athlete background (demographics, diagnosed medical history) and symptom evaluation (symptom items, total number of symptoms, and symptom severity score) of the Child SCAT5 and were instructed not to discuss reporting with each other during testing. Cronbach α tests were conducted to determine the internal consistency, and descriptive statistics determined the level of agreement between medical history, symptom reporting, and baseline performance.

RESULTS

The internal consistency of the symptom items was high for both child (Cronbach α = 0.91) and parent (α = 0.92). Agreement on medical history ranged from 67% (learning disability or dyslexia) to 85% (attention-deficit/hyperactivity disorder), with 82% agreement on sustaining a previous concussion. Fourteen youth athletes reported having been hospitalized for a head injury, with zero matched parent confirmations. Individual symptom agreement ranged from 70.7% (gets distracted easily) to 94.9% (going to faint). Agreement was 35% on total number of symptoms and severity. Abnormal scoring ranged from 2% (going to faint) to 25% (headache) for child and 2% (double vision) to 28% (gets distracted easily) for parent reporting.

CONCLUSIONS

Fair agreement was shown between children and their parent on medical history and self-reported symptoms on the Child SCAT5 at baseline. When available, child and parent reporting should be used for concussion assessment and clinical decision-making.

Investigating the association between subjective and objective performance-based cognitive function among former collegiate football players

OBJECTIVE

Studies have observed variable associations of prior contact sport participation with subjective and objective measures of cognitive function. This study directly investigated the association between subjective self-report and objective performance-based cognition among former collegiate football players, as well as its relationship to self-reported concussion history.

METHODS

Former collegiate football players (N = 57; mean age = 37.9 years [SD = 1.49]) retired from sport 15-years prior were enrolled. Linear regression models examined associations between subjective cognition (Quality of Life in Neurological Disorders Cognitive Functioning-Short Form), and performance on a neuropsychological battery. Domain specific (executive function) metrics of subjective (Behavior Rating Inventory of Executive Function-Adult) and objective cognition were also exclusively examined. Associations between self-reported concussion history with subjective and objective measures were tested. Potential influential factors (sleep quality and distress) were included as covariates.

RESULTS

Subjective cognition was not significantly associated with any objective measures of cognitive functioning (p's > .05). Greater self-reported concussion history was inversely associated with subjective cognition (B = -2.49, p = .004), but not objective performance-based cognition (p's > .05). Distress was significantly related to all metrics of subjective cognition (p's < .001) as well as performance on delayed recall and verbal fluency (p's < .05). Sleep quality was only significantly related to timed visuospatial sequencing (p = .033).

CONCLUSIONS

Reliance on self-reported measures of cognitive functioning alone is insufficient when assessing cognition in former contact sport athletes. Assessment of other factors known to influence subjective cognitive complaints should also be examined in determining the presence of cognitive deficits.

Prior Concussion History and Clinical Recovery Following Sport-Related Concussion in High School Athletes

Clinical recovery following sport-related concussion varies as a function of preinjury and acute factors. Whether, or the extent to which, concussion history is associated with clinical outcome following sport-related concussion is uncertain, as research has produced mixed findings. The present study aimed to assess whether a history of prior concussions is associated with prolonged clinical recovery following a subsequent sport-related concussion. The sample was comprised of 780 adolescent student athletes (mean age= M=16.3, SD=1.3 years; 56.8% boys, 43.2% girls) whose school participated in the Maine Concussion Management Initiative (MCMI). Survival analyses were used to compare recovery times among adolescents with a history of 0, 1, or 2 prior concussions following a subsequent sport-related concussion. The two primary outcomes of interest were the number of days to return to school and sports. There were no statistically significant differences in total time to return to school and sports, or the proportion of adolescents who returned to school and sports at most intervals (e.g., 7, 14, 28 days), between those with 0, 1, or 2 prior concussions. However, a greater proportion of adolescents with a history of 2 prior concussions remained out of sports at 28 days as compared to those with no prior concussions (23.5% vs. 12.7%; OR=2.10, 95% CI 1.18-3.73). Having sustained prior concussions was not associated with time to return to school following a subsequent sport-related concussion. However, a greater proportion of adolescents with two or more prior concussions experienced a prolonged return to sports. Further research is warranted to identify risk factors for worse outcomes among the subset of adolescents with a history of multiple prior concussions who experience prolonged recoveries.

Acute effects of concussion among adolescents with attention-deficit/hyperactivity disorder

Adolescents with ADHD have a greater lifetime history of concussion and experience concussion-like symptoms in the absence of a concussion, complicating concussion assessment and management. It is well established that individuals who experience greater acute symptoms following concussion are at risk for slower recovery and persistent symptoms. We examined whether youth with ADHD experience worse acute effects, within the first 72 h following concussion, compared to youth without ADHD. We hypothesized that youth with ADHD would perform worse on neurocognitive testing and endorse more severe symptoms acutely following injury, but the magnitude of change from pre injury to post injury would be similar for both groups, and thus comparable to baseline group differences. The sample included 852 adolescents with pre-injury and post-injury ImPACT results (within 72 h); we also conducted supplementary case-control analyses on a subset of youth with and without ADHD matched on demographics and pre-injury health history. For both samples, there were significant interaction effects for the Verbal Memory and Visual Motor Speed composites (p < 0.01, η²=.01-.07, small-medium effect), such that youth with ADHD showed a greater magnitude of diminished cognitive functioning from pre-injury to post-injury testing. There were no significant differences in the magnitudes of changes from pre injury to post injury with regard to overall symptom reporting (i.e., total symptom severity scores, total number of symptoms endorsed); however, there were group differences in endorsement rates for several individual symptoms. Further research is needed to determine whether such differential acute effects are associated with recovery time in youth with ADHD.

A Scoping Review of Magnetic Resonance Modalities Used in Detection of Persistent Postconcussion Symptoms in Pediatric Populations

Up to 30% of youth with concussion experience PPCSs (PPCS) lasting 4 weeks or longer, and can significantly impact quality of life. Magnetic resonance imaging (MRI) has the potential to increase understanding of causal mechanisms underlying PPCS. However, there are no clear modalities to assist in detecting PPCS. This scoping review aims to synthesize findings on utilization of MRI among children and youth with PPCS, and summarize progress and limitations. Thirty-six studies were included from 4907 identified papers. Many studies used multiple modalities, including (1) structural (n = 27) such as T1-weighted imaging, diffusion weighted imaging, and susceptibility weighted imaging; and (2) functional (n = 23) such as functional MRI and perfusion-weighted imaging. Findings were heterogeneous among modalities and regions of interest, which warrants future reviews that report on the patterns and potential advancements in the field. Consideration of modalities that target PPCS prediction and sensitive modalities that can supplement a biopsychosocial approach to PPCS would benefit future research.

What is a Repetitive Concussion in Sports?

OBJECTIVES Athletes are in a unique situation where they experience repeated concussions while participating in competitions. Although repeated exposure to a concussion has a high risk of negatively affecting athletes' performance and health after retirement, awareness of it is very low in athletes and sports associations. Therefore, the purpose of this review is to provide the basic information about the concussion problem that occurs repeatedly in sports and to establish the plan for the concussion reduction strategy.METHODS To provide the basic information related to a concussion problem in sports, the narrative review was applied.RESULTS The definition, symptoms and symptoms of a sports-related concussion, second impact syndrome, long-term sequelae from the concussion, the preventive effect of the helmet, and the guideline for the safe return to sports after concussion were discussed.CONCLUSIONS This study has reviewed the lack of awareness of concussions that occur repeatedly in the sports field and the problems related to the safety and health of the athletes. In order to reduce a concussion incidence and surrounding issues, the concussion reduction strategy has been proposed, and persistent interest is required from athletes, coaches, parents, and related sports organizations in relation to concussions.

Effects of a history of headache and migraine treatment on baseline neurocognitive function in young athletes

Objective/background

Despite the prevalence of concussions in young athletes, the impact of headaches on neurocognitive function at baseline is poorly understood. We analyze the effects of a history of headache treatment on baseline ImPACT composite scores in young athletes.

Methods

A total of 11,563 baseline ImPACT tests taken by 7,453 student-athletes ages 12-22 between 2009 and 2019 were reviewed. The first baseline test was included. There were 960 subjects who reported a history of treatment for headache and/or migraine (HA) and 5,715 controls (CT). The HA cohort included all subjects who self-reported a history of treatment for migraine or other type of headache on the standardized questionnaire. Chi-squared tests were used to compare demographic differences. Univariate and multivariate regression analyses were used to assess differences in baseline composite scores between cohorts while controlling for demographic differences and symptom burden.

Results

Unadjusted analyses demonstrated that HA was associated with increased symptoms (β=2.30, 95% CI: 2.18-2.41, p<.0001), decreased visual memory (β=-1.35, 95% CI: -2.62 to -0.43, p=.004), and increased visual motor speed (β=0.71, 95% CI: 0.23-1.19, p=.004) composite scores. Baseline scores for verbal memory, reaction time, and impulse control were not significantly different between cohorts. Adjusted analyses demonstrated similar results with HA patients having greater symptom burden (β=1.40, 95% CI: 1.10-1.70, p<.0001), lower visual memory (β=-1.25, 95% CI: -2.22 to -0.27, p=.01), and enhanced visual motor speed (β=0.60, 95% CI: 0.11-1.10, p=.02) scores.

Conclusion

HA affected symptom, visual motor speed, and visual memory ImPACT composite scores. Visual memory scores and symptom burden were significantly worse in the HA group while visual motor speed scores were better, which may have been due to higher stimulant use in the HA group. The effects of HA on visual motor speed and visual memory scores were independent of the effects of the increased symptom burden.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01432-w.

Child Sport Concussion Assessment Tool 5th Edition: Normative Reference Values in Demographically Diverse Youth

OBJECTIVES

Examine sociodemographic differences (gender, age, and language spoken at home) on baseline Child Sport Concussion Assessment Tool 5th Edition (Child SCAT5) scores and establish normative reference data for the Child SCAT5 among middle school student athletes.

DESIGN

Cross-sectional study.

SETTING

Nine middle schools in Virginia.

PARTICIPANTS

A sample of 1355 athletes playing competitive school-sponsored sports (ages 11-13, M = 12.3 ± 0.8; 40.1% girls, 59.9% boys) during the 2017 and 2018 school year. Certified athletic trainers administered the Child SCAT5 within the first 2 weeks of the sport season.

INDEPENDENT VARIABLES

Self-reported gender, age, and language spoken at home.

MAIN OUTCOME MEASURES

All Child SCAT5 outcome measures.

RESULTS

Gender, age, and language spoken at home were associated with Child SCAT5 scores, but the magnitude of differences was generally small. Specifically, girls endorsed more symptoms (girls: M = 8.4 ± 5.7, boys: M = 7.5 ± 5.7; P = 0.003) and greater symptom severity (girls: M = 11.6 ± 9.4, boys: M = 10.4 ± 9.3; P = 0.006) than boys and performed slightly better than boys on cognitive and balance tasks. Older students performed slightly better than younger students on tests of cognition (eg, SAC-C: 11-year-olds: M = 21.3 ± 2.1, 13-year-olds: M = 21.7 ± 2.1; P = 0.02). Total symptoms (P = 0.01), symptom severity (P = 0.01), immediate memory (P < 0.001), delayed recall (P = 0.001), and SAC-C total scores (P = 0.002) differed across language groups.

CONCLUSIONS

Gender, age, and language spoken in the home are associated with baseline scores on multiple components of the Child SCAT5 among middle school students, although the magnitudes of observed differences are small. Normative reference values are provided for clinicians when interpreting Child SCAT5 scores.

Attention-Deficit/Hyperactivity Disorder and Outcome from Concussion: Examining Duration of Active Rehabilitation and Clinical Recovery

AIMS

The objective of this study was to compare recovery time and duration of active rehabilitation following concussion between adolescents with and without attention-deficit/hyperactivity disorder (ADHD).

METHODS

A retrospective cohort study was conducted among adolescents presenting to a specialty concussion clinic. One-quarter of the eligible episodes of care were selected. The final sample included 540 adolescents (ages 13-17 years, median age 15 years; 49.8% girls), of which 65 (12.0%) had a pre-injury diagnosis of ADHD. Days to recovery and days of active rehabilitation were examined.

RESULTS

ADHD was not associated with recovery time (ADHD: median = 49 days, IQR = 25-77; No ADHD: median = 47 days, IQR = 29-85) in univariate (Z = -0.45; p = 0.65) or multivariable analyses (Hazard Ratio: 1.17 (0.85-1.61); χ²(1) = 0.95; p = 0.33). The duration of active rehabilitation services received did not differ between youth with ADHD (median = 38.5 days, IQR = 27.5-54.5) and without ADHD (median = 37.5 days, IQR = 18.5-66) in univariate (Z = -0.19; p = 0.85) or multivariable analyses (Hazard Ratio: 1.04 (0.67-1.63); χ²(1) = 0.03; p = 0.85).

CONCLUSIONS

Our findings support accumulating evidence that ADHD, in and of itself, is not a risk factor for longer recovery or worse outcomes following pediatric concussion.

Middle School Children With Attention-Deficit/Hyperactivity Disorder Have a Greater Concussion History

OBJECTIVE

Examine lifetime history of concussions in middle school student athletes who have attention-deficit/hyperactivity disorder (ADHD).

DESIGN

Cross-sectional study.

SETTING

Nine middle schools in Virginia, USA.

PARTICIPANTS

A sample of 1037 middle school students (ages 11-14 years, M = 12.6, SD = 0.93; 45.8% girls) underwent baseline/preseason assessments during the 2017 to 2018 academic year and self-reported their health history, including whether or not they had been diagnosed with ADHD. Athletes were divided into 2 groups, those with ADHD (n = 71; 6.8%) and control subjects (n = 966).

INDEPENDENT VARIABLES

Self-reported diagnosis of ADHD and self-identified sex.

MAIN OUTCOME MEASURES

Self-reported concussion history.

RESULTS

In the total sample, boys were more likely to report a previous history of concussion than girls [χ2(1) = 10.81, P = 0.001; odds ratio (OR) = 1.92; 95% confidence interval (CI), 1.30-2.85]. The rate of previous concussion in children with ADHD (23.9%) was twice the rate of previous concussion among children without ADHD (11.4%) [χ2(1) = 9.70, P = 0.002; OR = 2.45; 95% CI, 1.37-4.38]. Approximately 1 in 4 boys with ADHD (24.5%) and 1 in 5 girls with ADHD (22.2%) reported having sustained one or more previous concussions.

CONCLUSIONS

Attention-deficit/hyperactivity disorder is associated with a greater prevalence of previous concussion in middle school children. Further research is needed to understand the risk of sustaining concussion for young athletes with ADHD, as well as short- and long-term outcomes of concussion among young athletes with ADHD.

Research Letter: Sleep Mediates the Association Between Prior Concussion and Depressive Symptoms

OBJECTIVE

To test sleep quality as one mechanistic pathway through which repeated concussion increases risk of depression later in life among former contact sport athletes.

SETTING

Multicenter study enrolled former American collegiate football players from 16 different National Collegiate Athletic Association member institutions.

PARTICIPANTS

Fifty-eight former American collegiate football players approximately 15 years following sport discontinuation.

DESIGN

Participants completed in-person evaluations including comprehensive semistructured interviews with detailed concussion history and sport history, as well as self-reported measures of depression symptom severity (Beck Depression Inventory-II) and sleep quality (Pittsburgh Sleep Quality Index). Years of football participation were included as a covariate. Mediation modeling examined the degree to which sleep quality accounted for the association between repeated concussion and depression symptoms.

RESULTS

Within the mediation model, concussion history significantly predicted sleep quality (B = 1.03; 95% CI, 0.37 to 1.65; P = .002) and sleep quality significantly predicted depressive symptom severity (controlling for the effects of concussion history; B = 0.15; 95% CI, 0.06 to 0.24; P = .001). The association between prior concussion and depressive symptom severity was fully mediated by sleep quality. With inclusion of the indirect effects, concussion history did not predict depressive symptom severity (direct effect: B = 0.14; 95% CI, -0.09 to 0.41; P = .249; indirect effect: 0.15; 95% CI, 0.03 to 0.29; P = .016).

CONCLUSIONS

Current findings raise the possibility that the greater risk of depression reported in those with a history of mTBI/concussion is mediated by sleep quality, a common sequela of mTBI. These findings highlight potential opportunities for prophylactic sleep-related intervention among individuals with multiple prior concussions to mitigate the risk of depression.

Concussion reporting behaviors in student athletes across sexes and levels of contact

Context

Sport-related concussions (SRC) are common in student athletes. However, current literature suggests that many athletes do not accurately report their symptoms. The under-reporting of concussion symptoms can result in an increased risk of further injury and an underestimation of concussion prevalence.

Objective

This study aims to identify perspectives on concussion reporting behaviors in student athletes across levels of contact and by sex.

Design

Cross-sectional study.

Setting

Elementary and high school, college. Patients or other participants: 1126 female (52%) and male (48%) athletes, mean age 16.6 years. Main outcome measure(s): Standardized questionnaire on concussion reporting during a series of hypothetical scenarios.

Results

Student athletes participating in sports with higher levels of contact had more education about concussions, yet professed they were less likely to report a concussion. The most common reasons athletes chose not to report were ‘not wanting to miss the game’ and ‘not wanting to let the coach down.’ Minimal differences were found between sexes, with females being just as unlikely, or sometimes more unlikely, to report a concussion than males. Lastly, females playing contact and non-contact sports appear to be more concerned about not wanting to let their coach down than males.

Conclusions

Although perspective on concussion reporting behavior varied across sports of different levels of contact, we did not find any conclusive evidence of differences in willingness to report a concussion between sexes when compared within the same level of contact.

Examining Criteria for Defining Persistent Post-concussion Symptoms in Children and Adolescents

Researchers operationalize persistent post-concussion symptoms in children and adolescents using varied definitions. Many pre-existing conditions, personal characteristics, and current health issues can affect symptom endorsement rates in the absence of, or in combination with, a recent concussion, and the use of varied definitions can lead to differences in conclusions about persistent symptoms and recovery across studies. This study examined how endorsement rates varied by 14 different operational definitions of persistent post-concussion symptoms for uninjured boys and girls with and without pre-existing or current health problems. This cross-sectional study included a large sample (age range: 11–18) of girls (n = 21,923) and boys (n = 26,556) without a recent concussion who completed the Post-Concussion Symptom Scale at preseason baseline. Endorsements rates varied substantially by definition, health history, and current health issues. The most lenient definition (i.e., a single mild symptom) was endorsed by most participants (54.5% of boys/65.3% of girls). A large portion of participants with pre-existing mental health problems (42.7% of boys/51.5% of girls), current moderate psychological distress (70.9% of boys/72.4% of girls), and insufficient sleep prior to testing (33.4% of boys/47.6% of girls) endorsed symptoms consistent with mild ICD-10 postconcussional syndrome; whereas participants with no current or prior health problems rarely met this definition (1.6% of boys/1.6% of girls). The results illustrate the tremendous variability in the case definitions of persistent symptoms and the importance of harmonizing definitions across future studies.

A Systematic Review of Telehealth and Sport-Related Concussion: Baseline Testing, Diagnosis, and Management

Background: The use of telehealth has increased as a result of the COVID-19 pandemic. As sports at all levels resume, sports medicine physicians may be interested in how telehealth can be used for concussion care. Questions/Purpose: We sought to assess how telehealth has been used in the baseline testing, diagnosis, and/or management of concussion. Secondarily, we sought to assess the strengths and weaknesses of telehealth for concussion care and identify aspects of concussion care for which telehealth has not yet been studied. Methods: A systematic review was performed in September 2020 of PubMed and Embase using the following terms: concuss*, "mild traumatic brain," "head injur*," telehealth, telemedicine, telecare, "mobile health," m-health, virtual. Studies included were original research articles investigating the use of telehealth in the care of concussion (including baseline testing, diagnosis, and management), published in English, and had full text available. Results: A total of 356 articles were screened, of which 5 were determined to meet inclusion criteria. These articles described the use of telehealth for managing concussion in military and rural settings. No articles involved the use of telehealth for baseline concussion testing of athletes or for sideline evaluation. Conclusion: Despite the limited original research on the use of telehealth for concussion care, the articles identified provide a foundation for exploring the potential value of telehealth in the office practice and sports team setting. Telehealth may expand the ability of a sports medicine physician to provide timely and effective concussion care to athletes during the COVID-19 pandemic and beyond. More rigorous research is needed.

The relationship between resilience and neurophysiological stress in Special Operations Forces combat service members

Military resilience research is increasing due to the growing literature associating resilience with stress adaptation. This study aimed to investigate which physiological stress adaptation components were associated with resilience in Special Operations Forces combat service members. Special Operations Forces combat service members (n = 117) self-reported resilience (ER89) and lifetime clinician-confirmed mild traumatic brain injury history. Participants also underwent transcranial Doppler ultrasonography to measure middle cerebral artery velocity during rest and a breath-holding task. Neither resilience nor mild traumatic brain injury history was significantly associated with middle cerebral artery velocity percent increase following breath-holding; younger Special Operations Forces combat service members had a higher percent increase in middle cerebral artery velocity following a breath-holding task. Resilience was negatively associated with time to return to baseline middle cerebral artery velocity following peak velocity; whereas, mild traumatic brain injury history did not have a significant association. The Special Operations Forces combat service members that scored higher in resilience tended to return to baseline middle cerebral artery velocity following peak velocity faster than their less resilient counterparts. More resilient Special Operations Forces combat service members recovered faster from physiological stress (breath-holding) than less resilient counterparts. This is the first study to investigate resilience and cerebrovascular stress response and recovery in this population. Our initial findings indicated that the Ego Resiliency Scale may be an optimal resilience psychometric and should be used to evaluate effective military resilience trainings, which aim to improve performance and mental health.

Predictive Value of Subacute Heart Rate Variability for Determining Outcome Following Adolescent Concussion

Objective assessments of concussion recovery are crucial for facilitating effective clinical management. However, predictive tools for determining adolescent concussion outcomes are currently limited. Research suggests that heart rate variability (HRV) represents an indirect and objective marker of central and peripheral nervous system integration. Therefore, it may effectively identify underlying deficits and reliably predict the symptomology following concussion. Thus, the present study sought to evaluate the relationship between HRV and adolescent concussion outcomes. Furthermore, we sought to examine its predictive value for assessing outcomes. Fifty-five concussed adolescents (12–17 years old) recruited from a local sports medicine clinic were assessed during the initial subacute evaluation (within 15 days postinjury) and instructed to follow up for a post-acute evaluation. Self-reported clinical and depressive symptoms, neurobehavioral function, and cognitive performance were collected at each timepoint. Short-term HRV metrics via photoplethysmography were obtained under resting conditions and physiological stress. Regression analyses demonstrated significant associations between HRV metrics, clinical symptoms, neurobehavioral function, and cognitive performance at the subacute evaluation. Importantly, the analyses illustrated that subacute HRV metrics significantly predicted diminished post-acute neurobehavioral function and cognitive performance. These findings indicate that subacute HRV metrics may serve as a viable predictive biomarker for identifying underlying neurological dysfunction following concussion and predict late cognitive outcomes.

Athlete concussion history recall is underestimated: a validation study of self-reported concussion history among current professional rugby union players

Objective: To assess the concurrent validity and test re-test reliability of the Michigan Traumatic Brain Injury Identification Method (MTBIIM). The psychometric properties of this concussion index were investigated by comparing the agreement between player self-reported diagnosed concussions and medical record diagnosed concussions among professional rugby union players.Study Design: Cross-sectional study i) validation and ii) test re-test reliability.Methods: The MTBIIM was administered via a structured interview to obtain the number and nature of player self-reported concussion histories from players, while contracted to the host club. Self-reported concussion history information was compared to medically recorded data captured between 2008 and 2017. A mixed-effects logistic regression model explored predictors of player self-report accuracy.Results: Data from 62 players (25.39[4.36] years) included 99 unique rugby related concussions. Medically documented concussions (n = 92) per player (1.48 [1.96]) were 30% more than the mean number of self-reported diagnosed (n = 63) concussions per player (1.02 [1.21] events). Overall, self-reported diagnosed concussions and medical record diagnosed concussion histories had a 'fair' level of agreement (k=0.274; SE [0.076]), p=.001). Self-reported lifetime concussion history was signicantly negatively correlated with recall of concussions.Conclusions: Initial concurrent validity of the MTBIIM was found to be fair with the average athlete under-reporting the number of clinically diagnosed concussions.

Mental Health Symptoms Are Associated With Mild Traumatic Brain Injury History in Active Special Operations Forces (SOF) Combat and Combat Support Soldiers

INTRODUCTION

Special Operations Forces (SOF) combat arms and combat support Soldiers are at risk for impaired mental health, such as mood- and stress-related disorders, due to operational and training demands. Additionally, these individuals experience high risk for sustaining mild traumatic brain injury (mTBI). These mTBIs have also been linked to negative psychological outcomes, such as anxiety and depressive symptoms. Studying mental illnesses and their related symptoms alone does not fully address mental health, which may be better understood by 2 separate but overlapping continua measuring both mental illness and subjective well-being (ie, emotional, psychological, and social well-being). Due to the lack of research in this area, current mental health symptoms in active SOF combat Soldiers in relation to mTBI warrants investigation.

MATERIALS AND METHODS

In this study, 113 SOF combat and combat support Soldiers completed self-report psychological and mTBI history measures during an in-person laboratory setting. These psychometric measures included (1) psychological distress (Brief Symptom Inventory 18), (2) anxiety (Generalized Anxiety Disorder 7-item), (3) posttraumatic stress (PTSD Checklist for DSM-5), (4) somatization (Patient Health Questionnaire-15), and (5) subjective well-being (Mental Health Continuum Short Form).

RESULTS

On average, SOF combat Soldiers endorsed moderate well-being and low psychological distress, somatization, posttraumatic stress, and anxiety. Most SOF combat Soldiers had sustained 1 or more mTBI. We observed mTBI history had significant effects on each dependent variable in the expected directions. History of more mTBIs, controlling for age, was associated with lower subjective well-being as well as higher psychological distress, somatization, posttraumatic stress, and anxiety symptoms.

CONCLUSION

Although SOF combat Soldiers reported relatively adaptive mental health symptoms across participants, there was considerable variance in the measures reported. Some of the variance in mental health symptoms was accounted for by mTBI history while controlling for age, with reporting higher numbers of lifetime mTBIs and older age being associated with worse mental health symptoms. Longitudinal investigations into these associations and their impact on Soldier performance is warranted.

Network Structure of Physical, Cognitive, and Emotional Symptoms at Preseason Baseline in Student Athletes with Attention-Deficit/ Hyperactivity Disorder

OBJECTIVE

Preexisting attention-deficit/hyperactivity disorder (ADHD) may be a risk factor for worse outcome following sport-related concussion. We used a statistical and psychometric approach known as network analysis to examine the architecture of physical, cognitive, and emotional symptoms at preseason baseline among student athletes with ADHD.

METHOD

A cohort of 44,527 adolescent student athletes completed baseline preseason testing with ImPACT® between 2009 and 2015. A subsample of athletes reporting a diagnosis of ADHD and at least one symptom were included in this study (N = 3,074; 14-18 years old, 32.7% girls). All participants completed the 22-item Post-Concussion Symptom Scale at preseason baseline.

RESULTS

Student athletes reported high frequencies of difficulty concentrating (boys/girls = 50.7%/59.4%), emotional symptoms (nervousness: boys/girls = 30.2%/51.0%; irritability: boys/girls = 23.6%/34.8%; sadness: boys/girls = 21.4%/39.7%), sleep/arousal-related symptoms (trouble falling asleep: boys/girls = 39.5%/49.4%; sleeping less than usual: boys/girls = 36.2%/43.4%; and fatigue: boys/girls = 29.8%/36.4%), and headaches (boys/girls = 27.6%/39.0%) during preseason baseline testing. The most central symptoms included dizziness, which was related to multiple somatic symptoms, and increased emotionality, which was related to a cluster of emotional symptoms. Girls reported symptoms at a greater frequency than boys, and there was evidence for variance in the global strength of the symptom network across gender, but not specific intersymptom relationships.

CONCLUSION

In the absence of injury, symptoms that commonly occur after concussion interact and potentially reinforce each other among student athletes with ADHD at preseason. Symptoms common in ADHD (i.e., difficulty concentrating) are not necessarily the most central within the symptom network. These findings may inform more precise interventions for athletes with ADHD and prolonged recovery following concussion.

Systemic inflammation moderates the association of prior concussion with hippocampal volume and episodic memory in high school and collegiate athletes

BACKGROUND

There is a need to determine why prior concussion has been associated with adverse outcomes in some retired and active athletes. We examined whether serum inflammatory markers moderate the associations of prior concussion with hippocampal volumes and neurobehavioral functioning in active high school and collegiate athletes.

METHODS

Athletes (N = 201) completed pre-season clinical testing and serum collection (C-reactive protein [CRP]; Interleukin-6 [IL]-6; IL-1 receptor antagonist [RA]) and in-season neuroimaging. Linear mixed-effects models examined associations of prior concussion with inflammatory markers, self-reported symptoms, neurocognitive function, and hippocampal volumes. Models examined whether inflammatory markers moderated associations of concussion history and hippocampal volume and/or clinical measures.

RESULTS

Concussion history was significantly associated with higher symptom severity, p = 0.012, but not hippocampal volume or inflammatory markers (ps > 0.05). A significant interaction of prior concussion and CRP was observed for hippocampal volume, p = 0.006. Follow-up analyses showed that at high levels of CRP, athletes with two or more prior concussions had smaller hippocampal volume compared to athletes without prior concussion, p = 0.008. There was a significant interaction between prior concussion and levels of IL-1RA on memory scores, p = 0.044, i.e., at low levels of IL-1RA, athletes with two or more concussions had worse memory performance than those without prior concussion (p = 0.014).

CONCLUSION

Findings suggest that certain markers of systemic inflammation moderate the association between prior concussion and hippocampal volume and episodic memory performance. Current findings highlight potential markers for predicting at-risk individuals and identify therapeutic targets for mitigating the long-term adverse consequences of cumulative concussion.

Cumulative Effects of Prior Concussion and Primary Sport Participation on Brain Morphometry in Collegiate Athletes: A Study From the NCAA-DoD CARE Consortium

Prior studies have reported long-term differences in brain structure (brain morphometry) as being associated with cumulative concussion and contact sport participation. There is emerging evidence to suggest that similar effects of prior concussion and contact sport participation on brain morphometry may be present in younger cohorts of active athletes. We investigated the relationship between prior concussion and primary sport participation with subcortical and cortical structures in active collegiate contact sport and non-contact sport athletes. Contact sport athletes (CS; N = 190) and matched non-contact sport athletes (NCS; N = 95) completed baseline clinical testing and participated in up to four serial neuroimaging sessions across a 6-months period. Subcortical and cortical structural metrics were derived using FreeSurfer. Linear mixed-effects (LME) models examined the effects of years of primary sport participation and prior concussion (0, 1+) on brain structure and baseline clinical variables. Athletes with prior concussion across both groups reported significantly more baseline concussion and psychological symptoms (all ps < 0.05). The relationship between years of primary sport participation and thalamic volume differed between CS and NCS (p = 0.015), driven by a significant inverse association between primary years of participation and thalamic volume in CS (p = 0.007). Additional analyses limited to CS alone showed that the relationship between years of primary sport participation and dorsal striatal volume was moderated by concussion history (p = 0.042). Finally, CS with prior concussion had larger hippocampal volumes than CS without prior concussion (p = 0.015). Years of contact sport exposure and prior concussion(s) are associated with differences in subcortical volumes in young-adult, active collegiate athletes, consistent with prior literature in retired, primarily symptomatic contact sport athletes. Longitudinal follow-up studies in these athletes are needed to determine clinical significance of current findings.

Architecture of Physical, Cognitive, and Emotional Symptoms at Preseason Baseline in Adolescent Student Athletes With a History of Mental Health Problems

Objective: Pre-injury mental health problems are associated with greater symptom reporting following sport-related concussion. We applied a statistical and psychometric approach known as network analysis to examine the interrelationships among symptoms at baseline in adolescent student athletes with a history of mental health problems. Design: Cross-sectional study. Setting: High schools in Maine, USA. Participants: A cohort of 44,527 adolescent student athletes completed baseline preseason testing with ImPACT® between 2009 and 2015, and those with a history of mental health problems reporting at least one symptom were included (N = 2,412; 14-18 years-old, 60.1% girls). Independent Variables: Self-reported history of treatment for a psychiatric condition. Main Outcome Measures: Physical, cognitive, and emotional symptoms from the Post-Concussion Symptom Scale. Results: Student athletes reported high frequencies of emotional symptoms (nervousness: boys = 46.6%, girls = 58.3%; irritability: boys = 37.9%, girls = 46.9%; sadness: boys = 38.7%, girls = 53.2%), sleep/arousal-related symptoms (trouble falling asleep: boys = 50.4%, girls = 55.1%; sleeping less than usual: boys = 43.8%, girls = 45.2%; and fatigue: boys = 40.3%, girls = 45.2%), headaches (boys = 27.5%, girls = 41.8%), and inattention (boys = 47.8%, girls = 46.9%) before the start of the season. Although uncommonly endorsed, dizziness was the most central symptom (i.e., the symptom with the highest aggregate connectedness with different symptoms in the network), followed by feeling more emotional and feeling slowed down. Dizziness was related to physical and somatic symptoms (e.g., balance, headache, nausea, numbness/tingling) whereas increased emotionality was related to sadness, nervousness, and irritability. Feeling slowed down was connected to cognitive (e.g., fogginess, forgetfulness), and sensory symptoms (e.g., numbness/tingling, light sensitivity). There were no gender differences in the symptom network structure. Conclusions: We examined the interconnections between symptoms reported by student athletes with mental health problems at preseason baseline, identifying how physical, cognitive, and emotional symptoms interact and potentially reinforce each other in the absence of injury. These findings are a step toward informing more precise interventions for this subgroup of athletes if they are slow to recover following concussion.

Attention-Deficit/Hyperactivity Disorder Mimics the Post-concussion Syndrome in Adolescents

The objective of this study was to evaluate concussion-like symptom reporting among uninjured adolescents with Attention-deficit/hyperactivity disorder (ADHD), stratified by several cooccurring conditions, and to examine the base rate and predictors of uninjured adolescents with ADHD meeting diagnostic criteria for the International Classification of Diseases, 10th Revision (ICD-10) post-concussional syndrome (PCS). Participants in this cross-sectional, observational study, were drawn from a cohort of 48,834 adolescent student athletes from Maine (ages 13-18) with no concussion in the past 6 months who completed a preseason, baseline testing program between 2009 and 2015. The final sample included 3,031 students with ADHD, 2,146 (70.8%) boys and 885 (29.2%) girls. They were 15.2 years old on average (SD = 1.3). Concussion-like symptom reporting was more common in girls than boys. Most students with ADHD reported one or more symptoms (69.3% of boys and 81.1% of girls). The presence of an additional, co-occurring condition or comorbidity was associated with increased symptom reporting. In the absence of a recent concussion, 28.8% percent of boys and 47.1% of girls with ADHD endorsed symptoms resembling an ICD-10 diagnosis of post-concussional syndrome (PCS). Adolescents with pre-existing conditions were even more likely to endorse symptoms that resembled PCS (28-47% of boys and 45-69% of girls). Prior treatment for a psychiatric condition was the strongest independent predictor for meeting PCS criteria in boys, followed by treatment for migraines and co-occurring learning disorder. For girls, the only independent predictor was prior treatment of a psychiatric condition. In uninjured adolescent student athletes, ADHD appears to mimic the post-concussion syndrome. Adolescents with ADHD commonly endorse concussion-like symptoms in the absence of a recent concussion. Demographic characteristics (sex) and the presence of co-occurring conditions are related to symptom reporting in adolescents with ADHD. Understanding factors associated with baseline symptom reporting, such as pre-existing ADHD, is important when evaluating youth who have persistent symptoms following concussion as well as making both return to school and return to athletics decisions.

Adolescents With ADHD Do Not Take Longer to Recover From Concussion

The objective of this study was to determine whether adolescents with attention-deficit/hyperactivity disorder (ADHD) have prolonged return to school and sports following concussion compared to those without ADHD and whether medication status or concussion history is associated with recovery time. We hypothesized that having ADHD would not be associated with longer recovery time. This prospective observational cohort study, conducted between 2014 and 2019, examined concussion recovery among school sponsored athletics throughout Maine, USA. The sample included 623 adolescents, aged 14-19 years (mean = 16.3, standard deviation = 1.3 years), 43.8% girls, and 90 (14.4%) reported having ADHD. Concussions were identified by certified athletic trainers. We computed days to return to school (full time without accommodations) and days to return to sports (completed return to play protocol) following concussion. Adolescents with ADHD [median days = 7, interquartile range (IQR) = 3-13, range = 0-45] did not take longer than those without ADHD (median days = 7, IQR = 3-13, range = 0-231) to return to school (U = 22,642.0, p = 0.81, r = 0.01; log rank: χ 1 2 = 0.059, p = 0.81). Adolescents with ADHD (median days = 14, IQR = 10-20, range = 2-80) did not take longer than those without ADHD (median days = 15, IQR = 10-21, range = 1-210) to return to sports (U = 20,295.0, p = 0.38, r = 0.04; log rank: χ 1 2 = 0.511, p = 0.48). Medication status and concussion history were not associated with longer recovery times. Adolescents with ADHD did not take longer to functionally recover following concussion. Recovery times did not differ based on whether adolescents with ADHD reported taking medication to treat their ADHD or whether they reported a prior history of concussion.

Effects of a greater incentive to attack the head and face region on incidence of head kicks and concussions among male youth taekwondo competitors

BACKGROUND

In an attempt to improve the technical quality of sparring taekwondo, the World Taekwondo Federation has amended the competition rule for a head kick (HK), increasing the number of points awarded for this type of attack. The purpose of the current study was to: 1) evaluate the incidence of HKs and concussions; and 2) identify potential risk factors of concussions in sparring taekwondo.

METHODS

A postmatch, interview-based prospective cohort study was conducted with 145 sparring taekwondo athletes (12-16 years of age) who: 1) competed at a 2018 sparring-Taekwondo tournament; and 2) received a valid HK during competition. Incidence rates of HKs and concussions were estimated; possible risk factors or prognosticators of concussions were also analyzed using the chi-square test and binary logistic analysis.

RESULTS

Incidence rates of HKs and concussions were 133.5 (95% CI: 113.3-153.8) and 41.4 (95% CI: 29.6-53.3) per 1000 athlete-exposures, respectively. The binary logistic model revealed that athletes with no prior concussion history were less likely to experience a concussion (OR, 0.27; 95% CI: 0.1-0.7).

CONCLUSIONS

Although the incidence rates of HKs and concussions are considerably high, they are not increased compared with the results of pre-2009 studies. Therefore, the new competition rule relating to HKs did not appear to increase the incidence rates of HKs or concussions in our research participants. To prevent adverse effects related to repetitive HKs and concussions, continuous research is needed.

Children with Attention-Deficit/Hyperactivity Disorder Perform Differently on Pediatric Concussion Assessment

OBJECTIVE

To compare Child Sport Concussion Assessment Tool Fifth Edition (Child SCAT5) performance between uninjured children with attention-deficit/hyperactivity disorder (ADHD) and precisely matched controls without ADHD.

STUDY DESIGN

A nested case-control study was conducted within a cohort of middle school athletes (age 11-12 years) who completed preseason testing. Students with ADHD were individually matched to students without ADHD based on age, sex, language spoken at home, number of prior concussions, sport, and school they attended. The final sample included 54 students (27 with ADHD and 27 controls), 38 (70.4%) boys and 16 (29.6%) girls (average age: 11.7 years, SD = 0.5).

RESULTS

Children with ADHD reported more symptoms (M = 13.33, SD = 5.69, P < .001) and greater symptom severity (M = 22.59, SD = 1 1.60, P < .001) compared with controls (total symptoms: M = 6.44, SD = 4.96; symptom severity: M = 8.04, SD = 6.36). Children with ADHD performed similarly to controls on the Child SCAT5 cognitive tests. Children with ADHD committed 3 times as many total balance errors (median = 6) than children without ADHD (median = 2) and committed twice as many errors on single leg stance (ADHD median = 4; No ADHD median = 2) (P values < .001).

CONCLUSIONS

Children with ADHD endorsed more concussion-like symptoms and performed worse on balance testing during preseason Child SCAT5 assessment compared with matched controls without ADHD. These findings highlight the challenges of interpreting Child SCAT5 performance in children with ADHD following a concussion or suspected concussion and illustrate the value of administering the measure to children to document their pre-injury performance.

The Epidemiology of Sport-Related Concussion: What the Rehabilitation Clinician Needs to Know

Sport-related concussion is common in full-contact and collision sports. Epidemiology studies use different types of surveillance systems and concussion definitions. Concussion incidence rates vary across age, sex, sport, and level of competition. Incidence rates are increasing, likely due to higher rates of reporting following improved knowledge and increased regulations. In this review, we summarize 7 key concepts related to concussion epidemiology: concussion definition, changes in concussion knowledge, reliability and accuracy of injury surveillance systems, conservative management and return to play, reliability of self-report, incidence of concussion across levels of play, and understanding the behaviors of players, coaches, and medical personnel from a multidisciplinary management perspective. J Orthop Sports Phys Ther 2019;49(11):768-778. doi:10.2519/jospt.2019.9105.

Multi-parametric analysis reveals metabolic and vascular effects driving differences in BOLD-based cerebrovascular reactivity associated with a history of sport concussion

Objective: Identify alterations in cerebrovascular reactivity (CVR) based on the history of sport-related concussion (SRC). Further explore possible mechanisms underlying differences in vascular physiology using hemodynamic parameters modeled using calibrated magnetic resonance imaging (MRI). Method: End-tidal targeting and dual-echo MRI were combined to probe hypercapnic and hyperoxic challenges in athletes with (n = 32) and without (n = 31) a history of SRC. Concurrent blood oxygenation level dependent (BOLD) and arterial spin labeling (ASL) data were used to compute BOLD-CVR, ASL-CVR, and other physiological parameters including resting oxygen extraction fraction (OEF0) and cerebral blood volume (CBV0). Multiple linear and logistic regressions were then used to identify dominant parameters driving group-differences in BOLD-CVR. Results: Robust evidence for elevated BOLD-CVR were found in athletes with SRC history spreading over parts of the cortical hemispheres. Follow-up analyses showed co-localized differences in ASL-CVR (representing modulation of cerebral blood flow) and hemodynamic factors representing static vascular (i.e., CBV0) and metabolic (i.e., OEF0) effects suggesting that group-based differences in BOLD-CVR may be driven by a mixed effect from factors with vascular and metabolic origins. Conclusion: These results emphasize that while BOLD-CVR offers promises as a surrogate non-specific biomarker for cerebrovascular health following SRC, multiple hemodynamic parameters can affect its relative measurements. Abbreviations: [dHb]: concentration of deoxyhemoglobin; AFNI: Analysis of Functional NeuroImages ( https://afni.nimh.nih.gov ); ASL: arterial spin labeling; BIG: position group: defensive and offensive linemen; BIG-SKILL: position group: full backs, linebackers, running backs, tight-ends; BOLD: blood oxygen level dependent; CBF: cerebral blood flow; CMRO2: cerebral metabolic rate of oxygen consumption; CTL: group of control subjects; CVR: cerebrovascular reactivity; fMRI: functional magnetic resonance imaging; FSL: FMRIB software library ( https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/ ); HC: hypercapnia; HO: hyperoxia; HX: group with history of concussion; M: maximal theoretical BOLD signal upon complete removal of venous dHb; pCASL: pseudo-continuous arterial spin labeling; PETCO2: end-tidal carbon dioxide; PETO2: end-tidal oxygen; SCAT: sport-concussion assessment tool; SKILL: position group: defensive backs, kickers, quarterbacks, safeties, wide-receivers; SRC: sport-related concussion.

History of concussion and risk of subsequent injury in athletes and service members: A systematic review and meta-analysis

Risk of secondary injury after a primary concussion in sports and military contexts is an emerging area of interest in research. The purpose of this review was to provide an evidence synthesis describing risk of injury in athletic and military populations with and without a history of concussion. Electronic database searches were completed through September 7, 2018 in PubMed, EMBASE, CINAHL and SCOPUS. Peer-reviewed observational studies of any design with participants who were athletes or service members; measured the outcome of any type of injury; and compared injury between those with and without a history of concussion were included. Risk of bias was assessed using the Q-Coh II. Twenty-seven articles were included. Seventeen meta-analyses were completed for risk of any injury, risk of concussion, and risk of extremity injury using odds, hazard, and rate ratios. The results indicate significantly increased odds of all injuries (OR = 2.55; 95%CI 1.85,3.52); concussion (OR = 3.73; 95%CI 2.41,5.78); and lower extremity injuries (OR = 1.60; 95%CI 1.32,1.94) in those with a history of concussion compared to those without. Additional analyses reveal this increased risk is apparent when looking at time to event data and rate of injury based on number of exposures. While the reasons for the increased incidence of secondary injury associated with a concussion are not yet understood, there are potentially behavioral attributes and motor control deficits that contribute. It is suggested that research is needed to determine if active therapeutic treatment for disturbances in sensorimotor and neuromotor control after concussion could attenuate the increased risk for injury.

Age of First Exposure to American Football and Behavioral, Cognitive, Psychological, and Physical Outcomes in High School and Collegiate Football Players

BACKGROUND

Although some studies have observed a relationship between age of first exposure (AFE) to American football and long-term outcomes, recent findings in collegiate athletes did not observe a relationship between AFE and more intermediate outcomes at early adulthood. This, however, requires independent replication.

HYPOTHESIS

There will be no association between AFE to football and behavioral, cognitive, emotional/psychological, and physical functioning in high school and collegiate athletes.

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Active high school and collegiate football players (N = 1802) underwent a comprehensive preseason evaluation on several clinical outcome measures. Demographic and health variables that significantly differed across AFE groups were identified as potential covariates. General linear models (GLMs) with AFE as the independent variable were performed for each clinical outcome variable. Similar GLMs that included identified covariates, with AFE as the predictor, were subsequently performed for each clinical outcome variable.

RESULTS

After controlling for covariates of age, concussion history, race, and a diagnosis of ADHD, earlier AFE (<12 vs ≥12 years) did not significantly predict poorer performance on any clinical outcome measures (all P > 0.05). A single statistically significant association between AFE group and somatization score was recorded, with AFE <12 years exhibiting lower levels of somatization.

CONCLUSION

In a large cohort of active high school and collegiate football student-athletes, AFE before the age of 12 years was not associated with worse behavioral, cognitive, psychological, and physical (oculomotor functioning and postural stability) outcomes.

CLINICAL RELEVANCE

The current findings suggest that timing of onset of football exposure does not result in poorer functioning in adolescence and young adults and may contribute to resilience through decreased levels of physically related psychological distress.

Effect of concussion history on symptom burden and recovery following pediatric sports-related concussion

OBJECTIVE The aim of this study was to examine differences in symptom burden and duration until physician-documented clinical recovery among pediatric patients with sports-related concussion (SRC) with and without a history of concussion. METHODS A retrospective chart review was performed for all pediatric patients (7-19 years old) referred to the Pan Am Concussion Program in Winnipeg, Canada, with an SRC and evaluated < 30 days postinjury between September 1, 2013, and August 1, 2015. RESULTS A total of 322 patients with SRC (64.91% male, mean age 13.96 years) who were evaluated a median of 7 days (interquartile range [IQR] 5-11 days) postinjury were included. Patients without a history of concussion endorsed significantly fewer concussion symptoms at initial assessment (median 5.5 symptoms, IQR 1-10 symptoms) than those with a previous concussion (median 7 symptoms, IQR 2-13.25 symptoms; p = 0.036). The median Post-Concussion Symptom Scale scores were 9 (IQR 1-23) for patients with no concussion history and 13 (IQR 3-33) for those with a history of concussion (p = 0.032). For patients with no previous concussion, the median number of days until physician-documented clinical recovery was 23 (IQR 15-44 days) compared with 25 days (IQR 18-43 days) for those with a history of concussion (p = 0.281). There was no significant difference in the proportion of patients who experienced delayed time until physician-documented clinical recovery (> 1 month postinjury) between the groups (p = 0.584). CONCLUSIONS Although a history of concussion may be associated with increased symptom burden following pediatric SRC, there was no difference in the time until physician-documented clinical recovery. Pediatric patients with SRC who have a history of concussion should be managed on an individualized basis. Future work is needed to examine the short- and long-term effects of multiple concussions in children and adolescents.

Concussion attitudes, behaviors, and education among youth ages 12-17: Results from the 2014 YouthStyles survey

INTRODUCTION

This study assessed young athletes' (ages 12 to 17) concussion attitudes and behaviors, particularly their self-reported experience learning about concussion and intentions to report a concussion and disparities in these experiences.

METHODS

We used data from Porter Novelli's 2014 YouthStyles survey that is conducted each year to gather insights about American consumers.

RESULTS

Of the 1,005 respondents, 57% reported sports participation. Fourteen percent reported they may have had a previous concussion, and among them 41% reported having a concussion more than once while playing sports. Males (17.7%) were significantly more likely to report having a concussion than females (10.0%; χ² (1)=7.01, p=0.008). Fifty-five percent of respondents reported having learned about what to do if they think they may have a concussion, and 92% reported that they would tell their coach if they thought they sustained a concussion while playing youth or high school sports. Youth from higher income families ($75,000-$124,999) were significantly more likely than youth from lower income families (less than $35,000) to report that they learned about what do if they suspected that they had a concussion.

CONCLUSION

Age of athlete, parental income level, athlete's sex, and living in a metro versus non-metro area led to disparities in athletes' concussion education. There is a need for increased access to concussion education and an emphasis on customizing concussion education efforts to meet the needs of different groups.

PRACTICAL APPLICATION

We identified athletes' self-reported previously sustained concussions and predictors of education related to concussion. Further research is needed to explore the age, gender and income gaps in concussion education among athletes.

Consistency of traumatic brain injury reporting in older adults with and without cognitive impairment

OBJECTIVE

Medical history information regarding prior traumatic brain injury (TBI) usually relies on self-report, although little is known about the reliability of this information with regard to injuries sustained years or decades earlier. Even less is known about the reliability of self-reported medical history information in older individuals with cognitive impairment. To this end, we assessed the test-retest reliability of self-reported TBI history in a large, national sample.

METHODS

Participants (n = 4309) were older adults with intact cognition, mild cognitive impairment (MCI) and Alzheimer's disease (AD) from the National Alzheimer's Coordinating Center. Subjects provided TBI history information at baseline and one annual follow-up visit. Consistency of self-reported history of TBI with <5 minutes loss of consciousness (mLOC) and TBI with ≥5 mLOC reported at time 1 and 2 was analyzed across diagnostic groups.

RESULTS

Overall, subjects provided reports of TBI history at follow-up that were highly consistent with baseline reports (97.8-99.6% agreement), and Cohen's kappa coefficients were all larger than .80 and statistically significant, maximum p < .001. Furthermore, level of cognitive impairment was not a significant predictor of consistency in reporting.

CONCLUSIONS

These data are some of the first to suggest that self-report may be a consistent method of obtaining remote TBI history in the absence of medical records for older individuals, regardless of cognitive impairment.