Predictors of clinical recovery from concussion: a systematic review

Exercise-Induced Vision Dysfunction Early After Sport-Related Concussion Is Associated With Persistent Postconcussive Symptoms

OBJECTIVE

The purpose of this study was to determine if exercise-induced vision dysfunction [reduced performance and/or symptom exacerbation on a post-exercise King-Devick (KD) test] in adolescents early after sport-related concussion was associated with increased risk of persistent post-concussive symptoms (PPCS, recovery >28 days). We used exercise as a provocative maneuver before the KD test, hypothesizing that concussed adolescents with exercise-induced vision dysfunction would be more likely to develop PPCS.

DESIGN

Secondary analysis of data from a multi-center, randomized clinical trial comparing KD test performance before and after the Buffalo Concussion Treadmill Test in adolescents within 10 days of sport-related concussion who were randomized to aerobic exercise or placebo stretching program.

SETTING

Three university-associated sports medicine clinical programs.

PARTICIPANTS

Ninety-nine adolescents with sport-related concussion (exercise group: n = 50, 15.3 ± 1 years, 60% M, 22% with PPCS; stretching group: n = 49, 15.9 ± 1 years, 65% M, 35% with PPCS) tested a mean of 6 ± 2 days from injury.

INDEPENDENT VARIABLE

King-Devick test performed immediately before and 2 minutes after Buffalo Concussion Treadmill Test.

MAIN OUTCOME MEASURE

Persistent post-concussive symptoms.

RESULTS

Adolescents who demonstrated exercise-induced vision dysfunction upon initial evaluation developed PPCS at a significantly greater rate when compared with adolescents who did not (71% vs 34%, P < 0.001). Exercise-induced vision dysfunction corresponded to a relative risk of 3.13 for PPCS.

CONCLUSIONS

Adolescents with exercise-induced vision dysfunction had a 3-fold greater relative risk of developing PPCS than those without exercise-induced vision dysfunction.

Findings from a Randomized Controlled Trial of SMART: An EHealth Intervention for Mild Traumatic Brain Injury

OBJECTIVE

The aim of this study was to examine the efficacy of the SMART (Self-Management After Recent Traumatic brain injury) program and potential moderators.

METHODS

Parallel randomized controlled trial (ClinicalTrials.gov Identifier: NCT03498495) was conducted. Eligibility criteria included treatment for mild traumatic brain injury in the emergency department and age 11-18 years. Participants were assigned equally to SMART (n = 35) or usual care (UC; n = 36). SMART included symptom monitoring and online modules supporting the return to activities and symptom management. Coping and quality of life (QoL) (primary outcomes) and post-concussive symptoms (secondary outcome) were assessed at baseline and weekly for 4 weeks.

RESULTS

Groups did not differ in coping, QoL, or return to pre-injury symptom levels at any time point. Problem-focused engagement (PFE) moderated group differences over time (p = .02). At high PFE, UC participants reported lower QoL at time 1 (effect size [ES] = 0.60); SMART participants did not report a decline at any point. At low PFE, SMART participants reported declining QoL from pre-injury to time 1 (ES = 0.68), whereas UC participants reported an increase from time 1 to 3 (ES = 0.56). PFE also moderated group differences on the Health and Behavior Inventory (HBI) cognitive (p = .02) and somatic symptom scales (p = .05). At high PFE, SMART participants reported a more rapid return to pre-injury levels than UC participants (p = .05). Resilience also moderated group differences in QoL and HBI cognitive recovery.

CONCLUSION

Effectiveness of the SMART app varied based on preinjury coping styles and resilience, underscoring the potential need to tailor treatments to individual characteristics.

Comparison of Anxiety and Depression Symptoms in Concussed and Nonconcussed Adolescents

BACKGROUND

Few studies have examined psychiatric symptoms during the acute phase following a concussion in adolescents. Thus, this study compares anxiety and depression in acutely concussed and nonconcussed adolescents.

HYPOTHESIS

Acutely concussed adolescents will report greater anxiety and depressive symptoms compared with nonconcussed adolescents.

STUDY DESIGN

Prospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Data were collected from 282 adolescents (111 concussed within 28 days of injury, 171 nonconcussed), 13 to 18 years of age, who completed Patient-Reported Outcome Measurement Information System (PROMIS) Anxiety and Depressive Symptoms measures. We calculated average T-scores for anxiety and depression across both groups and compared the proportion of those who scored above normal limits. Finally, we calculated risk ratios for anxiety and depression scores above normal limits.

RESULTS

Average T-scores for anxiety did not differ in concussed versus nonconcussed adolescents (mean: 45.9 [SD 10.84] vs 45.2 [8.1], respectively, P = 0.54), whereas average T-scores for depression were significantly higher in concussed versus nonconcussed adolescents (46.0 [10.88] vs 42.8 [8.48], respectively, P < 0.01). The proportion of concussed adolescents above normal limits for depression was greater than nonconcussed adolescents (32.4% vs 20.5%, respectively, P = 0.02). Post hoc sensitivity analyses excluding those with a history of anxiety or depression demonstrated a 1.45 (95% CI, 0.97, 2.01) and 1.56 (95% CI, 0.95, 2.56) increased risk of an above-normal anxiety and depression score for concussed compared with nonconcussed adolescents, respectively, although both were nonsignificant.

CONCLUSION

Although we found few significant differences between the 2 groups, the results highlight that many concussed adolescents met the threshold for above-average symptoms on the depression and anxiety PROMIS measures.

CLINICAL RELEVANCE

In adolescents, there is increased risk for psychiatric sequalae in the acute period after a concussion. As such, we suggest that clinicians consider incorporating depression screening when caring for adolescents after a concussion.

Concussion in Ladies Gaelic Football: Self-reported History, Clinical Profiles, and Management Behavior

OBJECTIVE

To describe the prevalence, characteristics, and management behavior of self-reported sport-related concussion (SRC) in Ladies Gaelic Football (LGF) players.

DESIGN

Cross-sectional study.

SETTING

Online survey distributed to LGF clubs throughout Ireland.

PARTICIPANTS

Elite and nonelite adult LGF players (n = 657).

INTERVENTIONS

Participants were recruited by convenience sampling and answered an online survey. Questions on demographic characteristics, SRC history, symptoms, injury characteristics, and management behavior after SRCs that occurred while playing LGF during the previous season were included.

MAIN OUTCOME MEASURES

Overall concussion history, occurrence of an SRC during the previous LGF season, clinical profile scores, characteristics (eg mechanism and setting), and management behavior (eg following a graded RTP program) after SRCs that occurred during the previous season.

RESULTS

Approximately one-fifth (17.5%) of participants sustained a suspected or diagnosed SRC during the previous season, which was higher among elite (26.1%) than nonelite (15.3%) players ( P < 0.01). The highest scoring clinical profiles were the ocular and migraine profiles. Only 3.5% of respondents adhered to all SRC management recommendations. Although players who reported a medically diagnosed versus a suspected SRC more often followed these guidelines, SRC management beyond the initial phase of injury remained inadequate.

CONCLUSION

SRC is common in LGF; however, adherence to recommended management guidelines is poor, even among players who receive medical assistance. In particular, few LGF athletes receive clinical concussion care beyond the initial diagnosis and acute management phase. Further research is needed to examine the underlying reasons for poor SRC management in LGF, which will guide the development of future sport-specific interventions.

Cognitive and Behavioral Outcomes in Male and Female NCAA Soccer Athletes across Multiple Years: A CARE Consortium Study

PURPOSE

The purpose of this study was to determine changes in neurocognitive, psychosocial, and balance functioning in collegiate male and female soccer players across three consecutive years of baseline testing compared with a control group of noncontact athletes.

METHODS

Generalized estimating equations were used to compare changes in annual, preseason baseline measures of neurocognitive function, neurobehavioral and psychological symptoms, and postural stability between collegiate soccer players ( n = 75; 51 [68%] female soccer players) and noncontact athletes ( n = 210; 133 [63%] female noncontact athletes) across three consecutive years.

RESULTS

Among all participants, the group-time interaction was not significant for any outcome measures. Overall, soccer players reported lower (better) Brief Symptom Inventory 18 Depression ( P = 0.004, Exp(B) = 0.36, 95% confidence interval [CI] = 0.18-0.73), Global Severity Index ( P = 0.006, Exp(B) = 0.53, 95% CI = 0.33-0.84), and Post-Concussion Symptom Scale Symptom Severity ( P < 0.001, Exp(B) = 0.45, 95% CI = 0.22-0.95) scores than noncontact athletes. No other outcome measures were different between soccer players and noncontact athletes.

CONCLUSIONS

Among collegiate athletes, soccer players report similar or better psychosocial functioning and symptom scores than noncontact athletes. Importantly, neurocognitive functioning, neurobehavioral and psychological symptoms, and postural stability do not worsen over time in collegiate soccer players relative to their noncontact counterparts. Our findings suggest that despite possible exposure to repetitive head impacts, collegiate soccer players do not exhibit changes in observable function and symptoms across multiple seasons.

Concurrent Psychosocial Concerns and Post-Concussive Symptoms Following Pediatric mTBI: An A-CAP Study

OBJECTIVES

To measure the association between psychosocial problems and persistent post-concussive symptoms (PCS) in youth who were seen in the emergency department with mild traumatic brain injury (mTBI) or orthopedic injury (OI).

METHODS

From a larger prospective cohort study, Advancing Concussion Assessment in Pediatrics (A-CAP), 122 child-guardian pairs who presented to the emergency department with mTBI (N = 70) or OI (N = 52) were recruited for this cross-sectional sub-study. Each pair completed 2 measures assessing PCS burden at 2 weeks, 3 months, and 6 months post-injury. At one visit, pairs concurrently completed MyHEARTSMAP, a comprehensive, psychosocial self-assessment tool to evaluate 4 domains of mental wellness.

RESULTS

When measured at the same visit, children who self-reported moderate or severe Psychiatry domain concerns concurrently experienced a greater burden of cognitive symptoms (β = 5.49; 0.93-10.05) and higher overall PCS count (β = 2.59; 0.70-4.48) after adjusting for covariables, including retrospective pre-injury symptoms and injury group. Additionally, reports indicating mild Function domain severity were associated with increased cognitive (β = 3.34; 95% CI: 0.69-5.99) and somatic symptoms (β = 6.79; 2.15-11.42) and total symptom count (β = 1.29; 0.18-2.39).

CONCLUSION

Increasing severity in multiple domains of mental health is associated with more PCS in youth. While the differences in PCS between the mTBI and OI groups appeared somewhat larger for children with more mental health concerns, the interaction was not statistically significant; larger sample sizes are needed to evaluate the moderating effect of psychosocial difficulties on post-concussion symptoms.

Functional Outcomes, Injury Variables, and Athlete Characteristics Associated with Post-Concussion Sleep Disturbance

OBJECTIVE

To examine the relationship between sleep disturbance and functional outcomes following a concussion. Also, to explore athlete and injury-related variables that may be related to risk factors for poor sleep following concussion.

METHOD

124 collegiate athletes completed a neuropsychological evaluation within 14 days of sustaining a sport-related concussion (SRC). Athletes were categorized as sleep disturbed (n = 52) or not sleep disturbed (n = 72). Outcome variables included symptom reports, cognitive performance (mean performance and variability), and mood (depression). Injury characteristics and athlete characteristics explored were loss of consciousness (LOC) associated with the injury, whether the athlete was immediately removed from play, and history of prior concussions.

RESULTS

Sleep disturbed athletes reported more symptoms, F(4, 119) = 7.82, p < 0.001, ƞ2 = 0.21, were more likely to be symptomatic at the time of testing, χ2(1, N = 124) = 19.79, p < 0.001, φ = 0.40, and were marginally more likely to experience clinically significant depression, χ2(1, N = 120) = 3.03, p = 0.08, φ = 0.16, than not sleep disturbed athletes. There were no cognitive differences between the groups, p > 0.05. A greater proportion of sleep disturbed athletes experienced LOC (30%) compared to not sleep disturbed athletes (13%), χ2(1, N = 118) = 4.99, p = 0.03, φ = -0.21.

CONCLUSION

Sleep disturbances following SRC are associated with a broad range of self-reported symptoms. LOC may be associated with an increased risk of developing sleep disturbances; alternatively, sleep disturbances may increase the risk of LOC following concussion.

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.

Evidence for the Validation of a Single Item Recovery Question (SIRQ) in Children With Mild and Complicated Mild Traumatic Brain Injury

BACKGROUND

Recovery from a brain injury occurs in varying degrees. The objective of this study was to investigate the concurrent validity of a parent-reported 10-point scale for degree of recovery, Single Item Recovery Question (SIRQ), in children with mild traumatic brain injury (mTBI) or complicated mTBI (C-mTBI) compared with validated assessments of symptom burden (Post-Concussion Symptom Inventory Parent form-PCSI-P) and quality of life (Pediatric Quality of Life Inventory [PedsQL]).

METHODS

A survey was sent to parents of children aged five to 18 years who presented to pediatric level I trauma center with mTBI or C-mTBI. Data included parent-reported postinjury recovery and functioning of children. Pearson correlation coefficients (r) were calculated to measure the associations of the SIRQ with the PCSI-P and the PedsQL. Hierarchical linear regression models were used to examine if covariates would increase the predictive value of the SIRQ to the PCSI-P and the PedsQL total scores.

RESULTS

Of 285 responses (175 mTBI and 110 C-mTBI) analyzed, Pearson correlation coefficients for the SIRQ to the PCSI-P (r = -0.65, P < 0.001) and PedsQL total and subscale scores were all significant (P < 0.001) with mostly large-sized effects (r ≥ 0.500), regardless of mTBI classification. Covariates, including mTBI classification, age, gender, and years since injury, resulted in minimum changes in the predictive value of the SIRQ to the PCSI-P and the PedsQL total scores.

CONCLUSIONS

The findings demonstrate preliminary evidence for the concurrent validity of the SIRQ in pediatric mTBI and C-mTBI.

Exploratory Examination of Knee Self-Efficacy in Individuals With a History of ACL Reconstruction and Sport-Related Concussion

CONTEXT

Knee self-efficacy and injury-related fear are associated with poor self-reported knee function and decreased physical activity (PA) after ACL reconstruction (ACLR). Limited research has explored contextual factors that may influence psychological responses in this population, such as history of sport-related concussion (SRC). After SRC, individuals may experience increased negative emotions, such as sadness and nervousness. However, it is unknown how SRC history may influence knee-self efficacy and injury-related fear in individuals with ACLR. The purpose of this study was to compare knee self-efficacy and injury-related fear in individuals after ACLR who present with and without history of SRC.

DESIGN

Cross-sectional study.

METHODS

Forty participants ≥1 year postunilateral ACLR were separated by history of SRC (no SRC = 29, SRC = 11). The Knee Self-Efficacy Scale (KSES) and subscales measured certainty regarding performance of daily activities (KSES-ADL), sports/leisure activities (KSES-Sport), physical activities (KSES-PA), and future knee function (KSES-Future). The Tampa Scale of Kinesiophobia-11 measured injury-related fear. Mann-Whitney U tests were used to examine between-group differences. Hedges g effect sizes and 95% confidence interval were used to examine clinically meaningful group differences.

RESULTS

Individuals with a history of ACLR and SRC demonstrated worse KSES-PA (7.5 [5.3]) compared with those without a history of SRC (8.1 [6.1], P = .03). No other statistically significant differences were observed. A medium effect size was present for the KSES-PA (0.62), KSES-ADL (0.42), KSES-Present (ADL + PA + Sport) (0.48), KSES-Total (0.53), and Tampa Scale of Kinesiophobia-11 (0.61) but must be interpreted with caution as 95% confidence interval crossed 0.

CONCLUSIONS

This exploratory study indicated that individuals with a history of ACLR and SRC had worse knee self-efficacy for PA compared with those without history of SRC. Rehabilitation specialists should monitor knee self-efficacy deficits in the post-ACLR population and recognize the potential influence of cumulative injury history on rehabilitative outcomes.

Saliva Cortisol as a Biomarker of Injury in Youth Sport-Related Concussion

Increasing rates of sport-related concussion (SRC) in youth impose a significant burden on public health systems and the lives of young athletes. Accurate prediction for those likely to develop persistent post-concussion symptomology (PPCS) using a fluid biomarker, reflecting both acute injury and recovery processes, would provide the opportunity for early intervention. Cortisol, a stress hormone released through the hypothalamic-pituitary-adrenal (HPA) axis following injury, may provide a missing physiological link to clinical recovery. This cohort study investigated the change in saliva cortisol following SRC and the association between cortisol and symptom burden in pediatric ice hockey players. Further, the association between cortisol levels and medical clearance to return to play was explored. In total, cortisol samples from 233 players were included; 165 athletes (23.6% female) provided pre-injury saliva and 68 athletes (19.1% female) provided post-SRC saliva samples for cortisol analysis. Quantile (median) regressions were used to compare cortisol between pre-injury and post-SRC groups, and the association between total symptoms (/22) and symptom severity scores (/132) reported on the Sport Concussion Assessment Tool (SCAT)3/SCAT5 and post-SRC cortisol (adjusting for age, sex, history of concussion, and time from injury to sample collection). Results demonstrated significantly lower saliva cortisol in post-SRC athletes compared with the pre-injury group (β = -0.62, 95% confidence interval [CI; -1.08, -0.16], p = 0.009). Post-SRC cortisol was not significantly associated with the SCAT3/SCAT5 symptom totals or symptom severity scores; however, females were found to report more symptoms (β = 6.95, 95% CI [0.35, 13.55], p = 0.040) and greater symptom severity (β = 23.87, 95% CI [9.58, 38.15], p = 0.002) compared with males. Exploratory time-to-event analysis revealed a point estimate suggesting a potential association between low cortisol levels and days to medical clearance to return to play. Although preliminary, these findings suggest that the HPA axis may be dysregulated post-SRC. Further, our exploratory analysis and case presentation of post-injury outliers highlight the need to further research cortisol as a prognostic biomarker to inform individualized sex-specific care after SRC.

Approximating subject-specific brain injury models via scaling based on head-brain morphological relationships

Most human head/brain models represent a generic adult male head/brain. They may suffer in accuracy when investigating traumatic brain injury (TBI) on a subject-specific basis. Subject-specific models can be developed from neuroimages; however, neuroimages are not typically available in practice. In this study, we establish simple and elegant regression models between brain outer surface morphology and head dimensions measured from neuroimages along with age and sex information (N = 191; 141 males and 50 females with age ranging 14-25 years). The regression models are then used to approximate subject-specific brain models by scaling a generic counterpart, without using neuroimages. Model geometrical accuracy is assessed using adjusted [Formula: see text] and absolute percentage error (e.g., 0.720 and 3.09 ± 2.38%, respectively, for brain volume when incorporating tragion-to-top). For a subset of 11 subjects (from smallest to largest in brain volume), impact-induced brain strains are compared with those from "morphed models" derived from neuroimage-based mesh warping. We find that regional peak strains from the scaled subject-specific models are comparable to those of the morphed counterparts but could be considerably different from those of the generic model (e.g., linear regression slope of 1.01-1.03 for gray and white matter regions versus 1.16-1.19, or up to ~ 20% overestimation for the smallest brain studied). These results highlight the importance of incorporating brain morphological variations in impact simulation and demonstrate the feasibility of approximating subject-specific brain models without neuroimages using age, sex, and easily measurable head dimensions. The scaled models may improve subject specificity for future TBI investigations.

More Physical Activity Is Correlated With Reduction in Kinesiophobia for Adolescents With Persistent Symptoms After Concussion

CONTEXT

The relationship between physical activity (PA) and fear of pain with movement (ie, kinesiophobia) during concussion recovery is unknown. Kinesiophobia may limit PA, while PA after concussion may reduce kinesiophobia. Our purpose was to examine the correlation between PA and self-reported kinesiophobia during concussion recovery for adolescents with and without persistent symptoms.

DESIGN

Prospective cohort study of children ages 10-18 years within 14 days of concussion.

METHODS

Participants rated kinesiophobia using the Tampa Scale of Kinesiophobia (TSK) at initial (≤14 d postconcussion) and return to play (RTP) assessments, and wore activity monitors between assessments. Our primary outcome was TSK score change from initial to RTP assessments. We grouped participants based on whether they experienced persistent symptoms (symptoms ≥28 days) or not (symptoms <28 days) and calculated correlation coefficients (Pearson r for normally distributed and Spearman rho for nonnormally distributed variables) between PA variables and TSK change scores.

RESULTS

Among the 41 participants enrolled, 44% developed persistent symptoms (n = 18; age = 14.5 [2.0] y; 50% female; symptom duration = 57.3 [6.2] d; RTP = 66.8 [6.4] d) and 56% did not (n = 23; age = 14.9 [1.8] y; 48% female; symptom duration = 15.2 [1.5] d; RTP = 21.7 [1.9] d). For the persistent symptoms group, greater TSK change scores (mean = -2.5 [5.7] point change) were significantly and moderately correlated with higher daily step count (r = -.60, P = .008) and exercise frequency (r = -.63, P = .005), but were not correlated with exercise duration (ρ = -.12, P = .65). Among the no persistent symptoms group, TSK change scores (mean = -6.0 [5.0] point change) were not correlated with step count (r = -.18, P = .41) or exercise duration (ρ = .10, P = .67), and the correlation with frequency was low and not significant (r = -.34, P = .12).

CONCLUSIONS

Regular PA during concussion recovery, regardless of duration or intensity, may help reduce kinesiophobia for those experiencing persistent symptoms.

Attention-Deficit Hyperactivity Disorder and Learning Disabilities Modify Recovery and Sport Behavior Following Sport-Related Concussion

Limited evidence exists concerning how a diagnosis of attention-deficit hyperactivity disorder and/or learning disabilities (ADHD/LD) modifies recovery and behavior following sport-related concussion (SRC). To understand how ADHD/LD modifies the post-SRC experience, we conducted a retrospective cohort study of concussed young athletes through phone interviews with patients and guardians. Outcomes included time until symptom resolution (SR) and return-to-learn (RTL), plus subjective changes in post-SRC activity and sports behavior. Multivariate Cox and logistic regression was performed, adjusting for biopsychosocial characteristics. The ADHD/LD diagnosis was independently associated with worse outcomes, including lower likelihood to achieve SR (hazard ratio [HR] = 0.62, 95% confidence interval [CI] = [0.41-0.94]; P = .02) and RTL (HR = 0.55, 95% CI = [0.36-0.83]; P < .01) at any time following injury, and increased odds of changing sport behavior after concussion (odds ratio [OR] = 3.26, 95% CI = [1.26-8.42], P = .02), often to a safer style of play (62.5% vs 39.6%; P = .02) or retiring from the sport (37.5% vs 18.5%; P = .02). These results provide further evidence of the unique needs for athletes with ADHD/LD following SRC.

Long-term outcomes of major trauma patients with concussion

INTRODUCTION

Concussion may be sustained in the setting of injuries to multiple body regions and persistent effects of concussion may impact recovery. This project aimed to evaluate the association between concussion and 6-month and 12-month functional outcomes in survivors after major trauma.

METHODS

This was a registry-based cohort study that included adult patients with major trauma who presented to hospital between 01 Jan 2008 and 31 Dec 2017 and survived to hospital discharge. We excluded patients presenting with a Glasgow Coma Scale score <13 and those diagnosed with other intracranial injuries. Additionally, from the non-concussed group, patients with fractured skull and/or face were excluded, with the assumption that such patients may have had undiagnosed concussion. A good recovery was considered for Glasgow Outcome Scale-Extended (GOS-E) scores of 7 or 8. In addition, we assessed for patient reported anxiety and/or depression measured using the 3-level EuroQol 5 dimensions questionnaire. A modified mixed effects Poisson models with random intercepts for participant was used to assess the association between concussion and outcome.

RESULTS

There were 28,161 eligible patients and 12,822 met inclusion criteria. Concussion was diagnosed in 1860 patients (14.5%; 95%CI: 13.9-15.1). There was no association between concussion and good recovery at 12 months (aRR 1.05 (95%CI: 0.99-1.11). There was no association between concussion and anxiety and/or depression at 12 months (aRR 1.03; 95%CI: 0.99-1.07).

CONCLUSIONS

Concussion was sustained among 14.5% of included patients in the setting of major trauma but not associated with longer-term adverse outcomes using GOS-E. Concussed patients did not report differential rates of anxiety and/or depression.

Workplace Factors Associated With Return to Work After Mild-to-Moderate Traumatic Brain Injury

OBJECTIVE

Sociodemographic and injury-related predictors for return to work (RTW) after mild-to-moderate traumatic brain injury (TBI) have been extensively explored. However, there is a knowledge gap regarding work-related predictors of RTW. The main aim of this study was to explore work-related predictors of work participation 6 and 12 months after mild-to-moderate TBI.

SETTING

Data were collected at baseline 8 to 12 weeks after injury, and 3, 6, and 12 months after baseline, at a specialized TBI rehabilitation outpatient clinic at Oslo University Hospital, Oslo, Norway.

PARTICIPANTS

Eligible patients had suffered a mild-to-moderate TBI 8 to 12 weeks previously, were employed 50% or more at time of injury, were between 18 and 60 years of age, and sick listed 50% or more at time of inclusion due to symptoms of TBI (based on the Rivermead Post-Concussion Symptoms Questionnaire). In total, 116 patients were included in a randomized controlled trial, of whom 113 were included in the 1-year analysis.

DESIGN

Patients were originally included in a randomized controlled trial. There were no between-group differences in RTW after 1 year. Thus, the participants were evaluated as one cohort in this study.

MAIN MEASURES

The primary outcome measure was work participation 1 year after study inclusion. Work-related predictors were chosen on the basis of previous research and expert opinion and entered into a multivariable linear regression model. The model controlled for sociodemographic and injury-related factors.

RESULTS

The best-fitting model explained 25% of variation in work participation at 1 year. Significant predictors were predictability, quantitative demands and rewards (recognition) at the workplace, private or public employment, symptom burden at baseline, and sex.

CONCLUSION

In this study, several work-related predictors outperformed some of the established sociodemographic and injury-related predictors of RTW after TBI, thus stressing the need for further focus and research on amendable predictors of RTW after mild-to-moderate TBI.

Optimizing Concussion Care Seeking: A Longitudinal Analysis of Recovery

BACKGROUND

Approximately half of concussions go undisclosed and therefore undiagnosed. Among diagnosed concussions, 51% to 64% receive delayed medical care. Understanding the influence of undiagnosed concussions and delayed medical care would inform medical and education practices.

PURPOSE

To compare postconcussion longitudinal clinical outcomes among (1) individuals with no concussion history, all previous concussions diagnosed, and ≥1 previous concussion undiagnosed, as well as (2) those who have delayed versus immediate symptom onset, symptom reporting, and removal from activity after concussion.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Participants included 2758 military academy cadets and intercollegiate athletes diagnosed with concussion in the CARE Consortium. We determined (1) each participant's previous concussion diagnosis status self-reported at baseline (no history, all diagnosed, ≥1 undiagnosed) and (2) whether the participant had delayed or immediate symptom onset, symptom reporting, and removal from activity. We compared symptom severities, cognition, balance, and recovery duration at baseline, 24 to 48 hours, date of asymptomatic status, and date of unrestricted return to activity using tests of parallel profiles.

RESULTS

The ≥1 undiagnosed concussion group had higher baseline symptom burdens (P < .001) than the other 2 groups and poorer baseline verbal memory performance (P = .001) than the all diagnosed group; however, they became asymptomatic and returned to activity sooner than those with no history. Cadets/athletes who delayed symptom reporting had higher symptom burdens 24 to 48 hours after injury (mean ± SE; delayed, 28.8 ± 0.8; immediate, 20.6 ± 0.7), took a median difference of 2 days longer to become asymptomatic, and took 3 days longer to return to activity than those who had immediate symptom reporting. For every 30 minutes of continued participation after injury, days to asymptomatic status increased 8.1% (95% CI, 0.3%-16.4%).

CONCLUSION

Clinicians should expect that cadets/athletes who delay reporting concussion symptoms will have acutely higher symptom burdens and take 2 days longer to become asymptomatic. Educational messaging should emphasize the clinical benefits of seeking immediate care for concussion-like symptoms.

Traumatic Brain Injury History Among Individuals Using Mental Health and Addictions Services: A Scoping Review

OBJECTIVE

Traumatic brain injury (TBI) has been increasingly linked in population research to psychiatric problems as well as substance use and related harms, suggesting that individuals with TBI may also present more frequently to mental health and addictions (MHA) services. Little is known, however, about TBI history among MHA service users. The objectives of this review were to understand (i) the prevalence of TBI history among MHA service users; (ii) how TBI history is identified in MHA service settings; and (iii) predictors or outcomes of TBI that have been reported in MHA service users.

METHODS

A scoping review was conducted in accordance with PRISMA Scoping Review Extension guidelines. A search for relevant literature was conducted in MEDLINE, PsycINFO, SPORTDiscus, CINAHL, and Embase as well as various gray literature sources.

RESULTS

Twenty-eight relevant studies were identified. TBI was defined and operationalized heterogeneously between studies, and TBI history prevalence rates ranged considerably among the study samples. The included studies used varied methods to identify TBI history in MHA settings, such as clinical chart audits, single-item questions, or structured questionnaires (eg, Brain Injury Screening Questionnaire or Ohio State University TBI Identification Method). TBI history was most consistently associated with indicators of more severe substance use problems and mental health symptoms as well as increased aggression or risk to others. Studies reported less consistent findings regarding the relationship of TBI to physical health, cognitive impairment, functioning, risk to self, and type of psychiatric diagnosis.

CONCLUSION

Screening for TBI history in MHA settings may contribute important information for risk assessment and care planning. However, to be clinically useful, assessment of TBI history will require consistent operationalization of TBI as well as use of validated screening methods.

School performance in youth after a concussion

Objective

This study aimed to identify school problems and levels of cognitive activity in youths aged 5-18 years with a concussion during the recovery stages of return to school (RTS).

Study Design

In a prospective cohort, participants completed in-person assessments at three time points: First Visit Post-injury, Symptom Resolution Visit, and Follow-Up Visit. These time points varied based on the participants' recovery progress. The post-concussion symptom scale (PCSS) and a cognitive activity scale were completed every 2 days until symptom resolution was achieved. Participants and their parents completed a school questionnaire detailing how their concussion had impacted their school learning/performance and their level of concern about their injury as well as the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT).

Results

Sixty-three percent (N = 44/70) of participants returned to school by the First Visit Post-injury (average 7.7 days following injury), and of these, 50% (N = 22) were experiencing school problems. Sixty-five participants (out of 70) returned to school at the Follow-Up Visit, and of these, 18% reported school problems. There was a significant difference in the school problems reported by parents and youth. At the First Visit Post-injury, the youth reported more problems (p = 0.02), and the In-Person Symptom Resolution Visit with parents reported more problems (p = 0.01). The cognitive activity score increased, while the PCSS score decreased from RTS Stage 1 to Stage 5.

Conclusions

This study identified that 50% of youth experienced school problems at the First Visit Post-injury, whereas only 18% reported school problems at the Follow-Up Visit. There is a significant difference in the perception of school problems reported by youth and their parents at different stages of recovery. The amount and complexity of cognitive activity increased with decreasing symptoms and increasing RTS stage. Findings can guide youth with a concussion and their parents in supporting a cautious return to school with accommodations. Healthcare providers and researchers can use this knowledge to better support youth in their return to school and understand the importance of gathering information from youth and their parents to gain the best insight into recovery.

Concussion Recovery in Children and Adolescents: A Retrospective Study

Background

Concussion is a common injury among children and adolescents, with a growing body of literature supporting a variety of diagnostic and treatment modalities. Recovery is variable and depends on multiple factors that can be evaluated through a clinic visit: a thorough history, physical examination, and use of the Post-concussion Symptom Scale (PCSS).

Purpose/Hypothesis

The purpose of this study was to evaluate factors associated with overall recovery from concussion in children and adolescents in the clinical setting. It was hypothesized that the presence of 1 of a number of pre- or postinjury characteristics will be associated with poor concussion recovery.

Study Design

Case-control study; Level of evidence, 3.

Methods

We conducted a retrospective chart review of adolescents and children aged 6 to 17 years with a diagnosis of concussion who were evaluated at a single sports medicine center between January 2015 and December 2019. Cases were categorized into recovered (PCSS <7) and poorly recovered (PCSS ≥7) cohorts based on the last PCSS scores during clinical follow-ups for concussion management.

Results

Of the 162 charts reviewed, 110 cases met inclusion criteria. Significant statistical differences were found between the recovered and poorly recovered cohorts regarding mean days from injury to last clinic visit, previous migraine diagnosis, and emergency room (ER) visit before the first clinic visit (P < .01 for all). Binary logistic regression analysis revealed that the most predictive factors associated with poorer recovery were having an ER visit before the first clinic evaluation (P = .01) and previous migraine diagnosis (P = .04).

Conclusion

While many factors may contribute to overall recovery from concussion in pediatric populations, our study suggested that a history of migraine and an ER visit before clinic evaluation may be associated with poor recovery of concussive symptoms.

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.

Physical Activity Interventions in Rehabilitation Programs for Outpatients With Mild Traumatic Brain Injury

Introduction: There is limited scientific evidence about the optimal content and parameters of physical activity (PA) interventions for rehabilitation outpatients with persisting symptoms of a mild traumatic brain injury (mTBI). Clinicians have thus had to develop services based on their expertise, feasibility and patient needs. Objectives: This study aimed to document PA interventions delivered in specialized programs of a Canadian province offering outpatient rehabilitation services for individuals with persisting symptoms of mTBI to inform clinical intervention development and future research. Materials and methods: Cross-sectional study using an online survey containing 32 multiple choice and short open-ended questions to be answered by program administrators, with their clinical team's input. Content analysis and descriptive statistics were used. Results: Data from 94% of rehabilitation sites (n = 17) revealed that PA interventions are delivered to children (n = 4), adults (n = 15) and older adults (n = 5) with mTBI symptoms lasting ≥1 month to ≥1 year post injury. PA interventions aim to increase participation (n = 14), improve body functions (n = 9), manage persisting mTBI symptoms (n = 5) and improve self-management skills (n = 5) and knowledge (n = 4). Interventions include individual (n = 15) or group-based (n = 12) format, home-programs (n = 7), and teaching/education (n = 6). Most PA interventions include aerobic and resistance exercises. PA dosage parameters vary greatly. Conclusion: Clinical experts use multimodal interventions for rehabilitation program users that target improvement in body functions, participation and symptoms. The results can inform the development, enhancement and evaluation of PA interventions. Studies evaluating the effectiveness of these interventions for this clientele are warranted.

Is Overparenting Associated with Adolescent/Young Adult Emotional Functioning and Clinical Outcomes Following Concussion?

Overparenting (O-P), or "helicopter" parenting, has warranted increased attention across the past decade. It is characterized as being overly involved, protective, and low on granting autonomy, and is associated with deleterious psychosocial outcomes outside of the concussion literature. This study examined the association of overparenting and patient emotional distress and clinical outcomes (i.e., symptoms, neurocognitive test scores, recovery time) post-concussion. Adolescents/young adult concussion patients (injury < 30 days) and parents (N = 101 child-parent dyads) participated. Patient participants completed measures of depression, anxiety, stress, and concussion clinical outcomes while parents concurrently completed an overparenting measure. Results of a general linear model found that overparenting was associated with higher anxiety and stress report of the child. Overparenting had a significant positive correlation with concussion recovery, although of a small magnitude. Emotional distress level, but not overparenting, was moderately associated with worse performance on clinical outcomes, including neurocognitive testing, vestibular/ocular motor dysfunction, and concussion symptom severity.

Depressive Symptoms in Individuals With Persistent Postconcussion Symptoms: A Systematic Review and Meta-Analysis

IMPORTANCE

Approximately 15% to 30% of individuals with a history of concussion present with persistent postconcussion symptoms (PPCS). Individuals with PPCS are at greater risk of experiencing depressive symptoms.

OBJECTIVE

To synthesize the association between depressive symptoms and PPCS in children, adolescents, and adults via meta-analysis and to investigate potential moderators of that association.

DATA SOURCES

Systematic search of Ovid Medline, CINAHL, PsycInfo, and Embase from 1995 to January 2022 was performed. Additionally, references from included studies were hand-searched to ensure relevant articles were captured in the search.

STUDY SELECTION

Studies that involved participants who experienced PPCS and quantified depressive symptoms were included. The definition of PPCS was limited to physician-diagnosed or self-reported concussion, with symptoms lasting for a minimum of 4 weeks postinjury. Two authors independently screened all articles to determine study eligibility.

DATA EXTRACTION AND SYNTHESIS

Study characteristics were extracted independently by 2 trained investigators. Study data were meta-analyzed using a random-effects meta-analysis.

EXPOSURE

PPCS.

MAIN OUTCOMES AND MEASURES

The the primary outcome was depressive symptoms.

RESULTS

Data were extracted from 18 studies with a total of 9101 participants. Of the 18 studies, all were cohort studies, and 13 (72%) comprised adult populations. The mean (SD) time since concussion was 21.3 (18.7) weeks. After accounting for potential publication bias, the random-effects meta-analysis found a significant positive association between PPCS and depressive symptoms, (odds ratio, 4.56; 95% CI, 2.82-7.37; P < .001). There were no significant moderators, likely due to the small number of studies included.

CONCLUSIONS AND RELEVANCE

In this meta-analysis, experiencing PPCS was associated with a higher risk of experiencing depressive symptoms. There are several important clinical and health policy implications of the findings. Most notably, the development of strategies for effective prevention and earlier intervention to optimize mental health recovery following a concussion should be supported.

Greater Acute Concussion Symptoms Are Associated With Longer Recovery Times in Adolescents

We examined the association between the severity of acute concussion symptoms and time to return to school and to sports in adolescent student athletes. We hypothesized that there would be an association between the severity of acute symptoms experienced in the first 72 hours and functional recovery such that adolescents with the lowest burden of acute symptoms would have the fastest return to school and sports and those with the highest burden of symptoms would have the slowest return to school and sports. This injury surveillance cohort included 375 adolescent student athletes aged 14-19 years who sustained a sport-related concussion between 2014 and 2020. Athletic trainers documented time to return to school and to sports. A greater proportion of adolescents with the highest acute symptoms remained out of school at 3 (odds ratio [OR] = 2.5, 95% confidence interval [CI] 1.5-4.4), 5 (OR = 2.4, 95% CI 1.4-4.0), 7 (OR = 2.6, 95% CI 1.5-4.3), and 10 days (OR = 2.3, 95% CI 1.3-3.9) compared to those with the lowest acute symptoms. Similarly, a greater proportion of athletes with the highest acute symptoms remained out of sports at 7 (OR = 3.5, 95% CI 1.5-8.1), 10 (OR = 3.1, 95% CI 1.8-5.6), 14 (OR = 1.8, 95% CI 1.1-3.0), and 21 days (OR = 1.9, 95% CI 1.0-3.6) compared to those with the lowest acute symptoms. This study underscores the adverse effect of high acute symptom burden following concussion on return to school and to sports among adolescent student athletes. Conversely, student athletes with a low burden of acute symptoms have a faster return to school and to sports.

Serum neurofilament light as a biomarker of vulnerability to a second mild traumatic brain injury

A second mild traumatic brain injury (mTBI) sustained prior to neuropathological recovery can lead to exacerbated effects. Without objective indicators of this neuropathology, individuals may return to activities at risk of mTBI when their brain is still vulnerable. With axonal injury recognized as a neuropathological hallmark of mTBI, we hypothesized that serum levels of neurofilament light (NfL), a highly sensitive biomarker of axonal injury, may be predictive of vulnerability to worse outcomes in the event of a second mTBI. Given this hypothesis is difficult to test clinically, we used a two-hit model of mTBI in rats and staggered inter-injury intervals by 1-, 3-, 7-, or 14-days. Repeat-mTBI rats were dichotomized into NfL^high (NfL>median at the time of re-injury) and NfL^low (NfL<median) groups, with behavior and NfL levels analyzed throughout the 28-days, followed by ex vivo diffusion tensor imaging. NfL levels at the time of the second mTBI were found to be predictive of vulnerability to re-injury, with NfL^high rats displaying more neurological signs and a greater potentiation of NfL levels after the second mTBI. Importantly, this potentiation phenomenon remained even when limiting analyses to rats with longer inter-injury intervals, providing evidence that vulnerability to re-injury may not be exclusively dependent on inter-injury interval. Finally, NfL levels correlated with, and were predictive of, the severity of neurological signs following the second mTBI. These findings provide evidence that measurement of NfL during mTBI recovery may be reflective of the vulnerability to a second mTBI, and as such may have utility to assist return to sport, duty and work decisions.

A Pilot Randomized Controlled Trial of Docosahexaenoic Acid for the Treatment of Sport-Related Concussion in Adolescents

The objective was to examine the use of docosahexaenoic acid (DHA) for the treatment of sport-related concussion (SRC) in adolescent athletes. We hypothesize that participants who intake 2 g of DHA daily will not experience differences in recovery compared with participants who take a placebo. This double-blind, randomized controlled pilot trial was performed in a tertiary pediatric sports medicine clinic from 2013 to 2017 in adolescents (14-18 years) presenting with diagnosed SRC within 4 days of injury. Forty participants were randomized into DHA or PLACEBO group and were instructed to take 2 capsules twice daily for 12 weeks. Participants in the DHA group were symptom-free earlier than the PLACEBO group (11.0 vs 16.0 days, P = .08) and were cleared to begin the Return to Sport progression (14.0 vs 19.5 days, P = .12) sooner. The use of 2 g/day of DHA was well-tolerated and did not significantly affect recovery times in adolescent athletes following SRC.Clinical Trial Registration: ClincalTrials.gov, NCT01903525.

Dizziness Is Associated With Neck/Shoulder Pain Following Pediatric Concussion

OBJECTIVE

To examine the association between dizziness and neck/shoulder pain after concussion and if differences in postural stability and oculomotor function exist among patients reporting dizziness with or without concurrent neck/shoulder pain.

DESIGN

Cross sectional.

SETTING

Sports medicine clinic.

PATIENTS

Pediatric patients ≤14 days post concussion.

INTERVENTIONS

N/A.

OUTCOME MEASURES

Patients completed the Health and Behavior Inventory (HBI) symptom rating and separately rated neck/shoulder pain (scale 0-3; 0 = no pain). We grouped patients by HBI dizziness rating (0 = not-dizzy; 1-3 = dizzy) and compared neck/shoulder pain ratings between the groups. We then compared oculomotor and postural stability outcomes between dizzy patients with and without neck/shoulder pain.

RESULTS

We included 153 patients: dizzy (n = 100; age = 14.6 ± 2.2 years; 48% female) and not-dizzy (n = 53, age = 14.4 ± 3.1 years; 38% female). The dizzy group reported significantly higher neck/shoulder pain (1.4 ± 1.1 vs 0.5 ± 0.9 points, P < 0.001) and total symptom score (25.7 ± 11.2 vs 11.7 ± 9.3 points, P < 0.001) than the not-dizzy group. After adjusting for total symptom score and preinjury anxiety, depression, and migraines, dizziness was associated with higher odds of neck/shoulder pain (odds ratio = 1.9, 95% CI, 1.2-3.0; P = 0.004). No differences were observed between dizzy patients with and without neck/shoulder pain for near point of convergence (10.0 ± 7.5 vs 8.5 ± 6.7 cm, P = 0.43), modified Balance Error Scoring System (8.9 ± 5.5 vs 6.8 ± 4.7 errors, P = 0.09), or tandem gait (single-task: 26.0 ± 12.3 vs 24.2 ± 11.9 seconds, P = 0.56; dual-task: 35.1 ± 14.3 vs 35.6 ± 18.6 seconds, P = 0.90).

CONCLUSIONS

In concussion patients experiencing dizziness, evaluating neck/shoulder pain may help identify individuals who would benefit from cervical spine rehabilitation. However, other potential causes of dizziness should also be evaluated to facilitate timely recovery.

Factors Associated With Additional Clinic Visits in the Treatment of Sports-Related Concussion

OBJECTIVE

To evaluate the variables associated with additional concussion clinic visits before discharge to athletic trainer (AT).

DESIGN

Retrospective cohort study.

SETTING

Multidisciplinary Sports Concussion Center.

PATIENTS

Patients ages 12 to 23 years presenting with a sport-related concussion between January 11, 2017, and January 10, 2020, and were discharged to an AT.

METHODOLOGY

Our main outcome variable was being discharged to AT after the initial clinic visit versus those who attended additional clinic visits before AT discharge. We examined the influence of age, sex, initial visit symptom score, family and personal history of psychiatric disorders and migraines, history of prior concussions, and other variables on this outcome.

RESULTS

Of 524 patients, 236 were discharged to AT after the initial clinic visit, while 288 patients required additional clinic visits. The additional visit group had higher initial visit symptom scores ( P = 0.002), head imaging performed more frequently ( P < 0.02), a family history of psychiatric disorders and/or migraines ( P < 0.001, P < 0.001), more often reported a prior concussion ( P = 0.02), and was younger ( P = 0.014) compared with the one visit group. In a multiple variable model, the family history of psychiatric disorders [odds ratio (OR), 3.12 (95% CI, 1.531-6.343), P = 0.002], prior concussions [OR, 1.39 (95% CI, 1.020-1.892), P = 0.037], greater initial symptom score [OR, 1.05 (95% CI, 1.031-1.058), P < 0.001], and younger age [OR, 0.87 (95% CI, 0.773-0.979), P = 0.021] were strongly associated with additional visits.

CONCLUSIONS

Among athletes treated at a regional sports concussion center, family history of psychiatric disorders, increased symptom score at initial visit, prior concussions, and younger age were each uniquely associated with needing additional clinic visits at the time of initial assessment. Understanding these variables may guide treatment protocols for optimal care.

Early Postinjury Screen Time and Concussion Recovery

OBJECTIVES

To determine the association between early screen time (7-10 days postinjury) and postconcussion symptom severity in children and adolescents with concussion, as compared to those with orthopedic injury (OI).

METHODS

This was a planned secondary analysis of a prospective longitudinal cohort study. Participants were 633 children and adolescents with acute concussion and 334 with OI aged 8 to 16, recruited from 5 Canadian pediatric emergency departments. Postconcussion symptoms were measured using the Health and Behavior Inventory at 7 to 10 days, weekly for 3 months, and biweekly from 3 to 6 months postinjury. Screen time was measured by using the Healthy Lifestyle Behavior Questionnaire. Generalized least squares models were fit for 4 Health and Behavior Inventory outcomes (self- and parent-reported cognitive and somatic symptoms), with predictors including screen time, covariates associated with concussion recovery, and 2 3-way interactions (self- and parent-reported screen time with group and time postinjury).

RESULTS

Screen time was a significant but nonlinear moderator of group differences in postconcussion symptom severity for parent-reported somatic (P = .01) and self-reported cognitive symptoms (P = .03). Low and high screen time were both associated with relatively more severe symptoms in the concussion group compared to the OI group during the first 30 days postinjury but not after 30 days. Other risk factors and health behaviors had stronger associations with symptom severity than screen time.

CONCLUSIONS

The association of early screen time with postconcussion symptoms is not linear. Recommending moderation in screen time may be the best approach to clinical management.

Relationship Between Self-Reported Concomitant Depressive and Anxiety Symptoms and the Post-Concussion Symptoms Scale (PCSS)

OBJECTIVES

The current study explored how affective disturbances, particularly concomitant anxiety and depressive symptoms, impact baseline symptom self-reporting on the Post-Concussion Symptoms Scale (PCSS) in college athletes.

METHODS

Athletes were separated into four groups (Healthy Control (HC) (n = 581), Depression Only (n = 136), Anxiety Only (n = 54), Concomitant Depression/Anxiety (n = 62)) based on their anxiety and depression scores. Groups were compared on Total PCSS Score as well as 5 PCSS Symptom Cluster scores (Cognitive, Physical, Affective, Sleep, and Headache).

RESULTS

The three affective groups reported significantly greater symptomatology than HCs, with the Concomitant group showing the highest symptomatology scores across all clusters. The depressive symptoms only group also reported significantly elevated symptomatology, compared to HCs, on every symptom cluster except headache. The anxiety symptoms only group differed from HCs on only the cognitive symptoms cluster. Additionally, the Concomitant group reported significantly increased PCSS symptomatology, in terms of total scores and all 5 symptom clusters, compared to the depressive symptoms only and anxiety symptoms only groups.

CONCLUSIONS

Our findings suggest that athletes experiencing concomitant depressive/anxiety symptoms report significantly greater levels of symptomatology across all 5 PCSS symptom clusters compared to HCs. Further, results suggest that athletes experiencing concomitant affective disturbance tend to report greater symptomatology than those with only one affective disturbance. These findings are important because, despite the absence of concussion, the concomitant group demonstrated significantly elevated symptomatology at baseline. Thus, future comparisons with post-concussion data should account for this increased symptomatology, as test results may be skewed by affective disturbances at baseline.

Association of Concussion History and Prolonged Recovery in Youth

OBJECTIVE

To determine the number of prior concussions associated with increased incidence of persistent postconcussive symptoms (PPCS) in a cohort of acutely concussed pediatric patients.

DESIGN

Prospective observational cohort study.

SETTING

Three university-affiliated concussion clinics.

PARTICIPANTS

Two hundred seventy participants (14.9 ± 1.9 years, 62% male, 54% with prior concussion) were assessed within 14 days of concussion and followed to clinical recovery. Participants with a second head injury before clinical recovery were excluded.

MEASURES AND MAIN OUTCOME

Concussion history, current injury characteristics, recovery time, and risk for prolonged recovery from current concussion.

RESULTS

There was no statistically significant change in PPCS risk for participants with 0, 1 or 2 prior concussions; however, participants with 3 or more prior concussions had a significantly greater risk of PPCS. Twelve participants sustained a subsequent concussion after clinical recovery from their first injury and were treated as a separate cohort. Our secondary analysis found that these participants took longer to recover and had a greater incidence of PPCS during recovery from their latest concussion.

CONCLUSION

Pediatric patients with a history of 3 or more concussions are at greater risk of PPCS than those with fewer than 3 prior concussions.

Clinical Outcome Following Concussion Among College Athletes with a History of Prior Concussion: A Systematic Review

BACKGROUND

There is long-standing interest in, and concern about, whether collegiate athletes with a history of concussion will experience worse clinical outcomes, or prolonged recovery, should they sustain a subsequent concussion.

OBJECTIVES

This systematic review examined the association between prior concussion history and clinical outcomes following a subsequent sport-related concussion among college-age student athletes.

STUDY DESIGN

Systematic review.

METHODS

We screened 5,118 abstracts and 619 full-text articles that were appraised to determine whether they met inclusion criteria. We utilized a likelihood heuristic to assess the probability of observing a specific number of statistically significant and nonsignificant studies reporting an association between concussion history and clinical outcomes. We conducted a narrative synthesis of the study findings.

RESULTS

Sixteen studies met the inclusion criteria. Thirteen studies reported the number of participants with a history of prior concussions (≥ 1), which totaled 1690 of 4573 total participants (on average 37.0% of study participants; median = 46.0%, range 5.6-63.8%). On the Newcastle-Ottawa Quality Assessment Scale, the risk of bias ratings ranged from 3 to 9 (mean = 5.4, SD = 1.4). Across all studies, 43.8% (k = 7/16) reported at least one statistically significant result among primary analyses showing an association between concussion history and worse clinical outcome. A minority of studies reporting on symptom duration (4/13, 30.8%) and time to return to play (2/7, 28.6%) found an association between concussion history and worse outcome. Studies included in the review reported limited information pertaining to the characteristics of prior concussions, such as presence or duration of loss of consciousness or posttraumatic amnesia, age at first lifetime concussion, time since most recent past concussion, or length of recovery from prior concussions.

CONCLUSION

The question of whether college athletes with a prior history of concussion have worse clinical outcome from their next sport-related concussion remains unresolved. The published results are mixed and in aggregate show modest evidence for an association. Many studies have small samples, and only three studies were designed specifically to address this research question. Important outcomes, such as time to return to academics, have not been adequately studied. Larger hypothesis-driven studies considering the number of prior concussions (e.g., 3 or more) are needed.

TRIAL REGISTRATION

PROSPERO CRD42016041479, CRD42019128300.

Gender and Workplace Stress Affect the Association Between Concussion History and Depression Symptoms in Professional Jockeys

Objective

Professional jockeys experience high rates of concussion, workplace stress, and poor mental health. The present cross-sectional study, for the first time, concurrently assessed the potential interplay between concussion history and workplace stress with current depression symptoms.

Method

Seventy-two professional flat-track jockeys (male = 49, female = 23) were grouped based on self-reported concussion history (CG; n = 56) and those who did not report a concussion history (NCG; total n = 16). Analyses featured both between (CG vs NCG) and within group (CG only) assessment on self-reported measures of workplace stress and depression symptoms (affect, daily functioning).

Results

Jockeys in the CG had more symptoms of negative affect than the NCG. This association, however, was nonsignificant after covarying for age, gender, and workplace stress. Higher workplace stress (p = .005) and gender (p = .001) were associated with poorer daily functioning after controlling for concussion history (CG vs. NCG) and age. Gender moderated the association between concussion group and poorer daily functioning (β = −18.739, t (71) = −2.924, p = .005), with the difference between CG and NCG significant for females, but not males (β = 33.648, t (71) = 3.420, p = .001).

Conclusions

The findings provide preliminary evidence that previously concussed females may be more likely to report poorer daily functioning than males with a history of concussion, and that workplace stress may reduce the association between a history of concussion and depression symptoms. Prospective studies are required to validate and extend these findings.

Monitoring the acute and subacute recovery of cognitive ocular motor changes after a sports-related concussion

Identifying when recovery from a sports-related concussion (SRC) has occurred remains a challenge in clinical practice. This study investigated the utility of ocular motor (OM) assessment to monitor recovery post-SRC between sexes and compared to common clinical measures. From 139 preseason baseline assessments (i.e. before they sustained an SRC), 18 (12 males, 6 females) consequent SRCs were sustained and the longitudinal follow-ups were collected at 2, 6, and 13 days post-SRC. Participants completed visually guided, antisaccade (AS), and memory-guided saccade tasks requiring a saccade toward, away from, and to a remembered target, respectively. Changes in latency (processing speed), visual–spatial accuracy, and errors were measured. Clinical measures included The Sports Concussion Assessment Tool, King-Devick test, Stroop task, and Digit span. AS latency was significantly longer at 2 days and returned to baseline by 13-days post-SRC in females only (P &lt; 0.001). Symptom numbers recovered from 2 to 6 days and 13 days (P &lt; 0.05). Persistently poorer AS visual–spatial accuracy was identified at 2, 6 and 13 days post-SRC (P &lt; 0.05) in both males and females but with differing trajectories. Clinical measures demonstrated consistent improvement reminiscent of practice effects. OM saccade assessment may have improved utility in tracking recovery compared to conventional measures and between sexes.

Somatization in Adolescents With Persistent Symptoms After Concussion: A Retrospective Chart Review

OBJECTIVE

After concussion, approximately 30% of adolescents experience symptoms that persist beyond 1 month postinjury. For some, these symptoms affect functioning, development, and quality of life. Somatization, where psychological distress contributes to physical symptoms, may contribute to persistent symptoms after concussion in some adolescents. Understanding how clinicians identify somatization in adolescents with persistent symptoms after concussion in practice is a critical next step in improving our understanding, identification, and subsequent treatment of somatization in this patient population. To address this, the investigators assessed and compared characteristics of adolescents with persistent symptoms after concussion with and without clinician-identified somatization.

METHODS

Participants were adolescents (N=94) referred for persistent symptoms after concussion to a specialty youth concussion clinic between January 2016 and May 2018. A retrospective chart review extracted demographic and injury characteristics, symptoms after concussion, school attendance, premorbid experiences, mental health, and medical service use. Participants with physician-identified somatization were compared with those without physician-identified somatization on these measures.

RESULTS

Adolescents with identified somatization had more severe and atypical neurological and psychiatric symptoms after concussion and more postinjury impairment in school attendance, were more likely to have a history of premorbid chronic pain or medically unexplained symptoms, and obtained more neuroimaging and health care after injury compared with those unaffected by somatization. They did not differ in mood or anxiety symptom self-reports.

CONCLUSIONS

This study identified characteristic differences and similarities in adolescents with and without clinician-identified somatization after a prolonged concussion recovery. These findings have the potential to improve clinical identification of somatization in youths following a concussion and may aid in treatment among this demographic group.

Nutritional interventions to support acute mTBI recovery

When mild traumatic brain injury (mTBI) occurs following an impact on the head or body, the brain is disrupted leading to a series of metabolic events that may alter the brain's ability to function and repair itself. These changes may place increased nutritional demands on the body. Little is known on whether nutritional interventions are safe for patients to implement post mTBI and whether they may improve recovery outcomes. To address this knowledge gap, we conducted a systematic review to determine what nutritional interventions have been prescribed to humans diagnosed with mTBI during its acute period (<14 days) to support, facilitate, and result in measured recovery outcomes.

Methods

Databases CINAHL, PubMed, SPORTDiscus, Web of Science, and the Cochrane Library were searched from inception until January 6, 2021; 4,848 studies were identified. After removing duplicates and applying the inclusion and exclusion criteria, this systematic review included 11 full papers.

Results

Patients that consumed enough food to meet calorie and macronutrient (protein) needs specific to their injury severity and sex within 96 h post mTBI had a reduced length of stay in hospital. In addition, patients receiving nutrients and non-nutrient support within 24-96 h post mTBI had positive recovery outcomes. These interventions included omega-3 fatty acids (DHA and EPA), vitamin D, mineral magnesium oxide, amino acid derivative N-acetyl cysteine, hyperosmolar sodium lactate, and nootropic cerebrolysin demonstrated positive recovery outcomes, such as symptom resolution, improved cognitive function, and replenished nutrient deficiencies (vitamin D) for patients post mTBI.

Conclusion

Our findings suggest that nutrition plays a positive role during acute mTBI recovery. Following mTBI, patient needs are unique, and this review presents the potential for certain nutritional therapies to support the brain in recovery, specifically omega-3 fatty acids. However, due to the heterogenicity nature of the studies available at present, it is not possible to make definitive recommendations.

Systematic review registration

The systematic review conducted following the PRISMA guidelines protocol was registered (CRD42021226819), on Prospero.

Sex comparisons in neuropsychological functioning and reported symptoms following a sports-related concussion among high school athletes

The aim of this study was to compare the neuropsychological functioning and symptoms of female and male high school athletes following a single concussion during the school year. The baseline test scores of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) of 309 concussed athletes (169 females, 221 males) in varied sports were obtained. After a sport-related concussion, the athletes were re-administered the ImPACT, on the average, 7.25 days after the injury. MANCOVA compared the ImPACT baseline scores, post-concussion scores, and baseline-to-post-concussion changes of the female and male athletes, with p set at 0.01. The only significant sex comparison found females performing better on baseline visual motor speed (p < 0.001). Otherwise, no sex differences were found in baseline test scores, post-concussion scores, and baseline-to-post-concussion changes. The findings tentatively suggest that there are insignificant sex differences in the consequences of sport-related concussion after a week post-injury. Future studies on sex comparisons after a concussion are needed focusing on the acute and sub-acute phases of the recovery period.

Evaluation of differences across age groups in the incidence, severity, and recovery of concussion in adolescent student-athletes from 2009 to 2019

OBJECTIVE

Concussion incidence is known to be highest in children and adolescents; however, there is conflicting evidence about the effect of age on concussion risk and recovery within the adolescent age range. The heterogeneity of results may be partially due to the use of age groupings based on convenience, making comparisons across studies difficult. This study evaluated the independent effect of age on concussion incidence, severity, and recovery in student-athletes aged 12-18 years using cluster analysis to define groupings.

METHODS

Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores of 11,403 baseline tests and 4922 postinjury tests were used to calculate the incidence rates for adolescent student-athletes grouped into 3 age bands (12-13, 14-15, and 16-18 years of age) on the basis of clustering analysis. The recently created Severity Index was used to compare concussion severity between groups. Follow-up tests for subjects who sustained a concussion were used to evaluate recovery time. The chi-square test and 1-way ANOVA were used to compare differences in demographic characteristics and concussion incidence, severity, and recovery. Multivariable logistic and linear regressions were used to evaluate the independent effects of age on concussion incidence and severity, respectively. Multivariable Cox hazard regression was used to evaluate differences in recovery time. Further analyses were conducted to directly compare findings across studies on the basis of the age groupings used in prior studies.

RESULTS

Multivariable regression analyses demonstrated that the 14- to 15-year-old age group had a significantly higher concussion incidence than both the 12- to 13-year-old (14- to 15-year-old group vs 12- to 13-year-old group, OR 1.57, 95% CI 1.16-2.17, p = 0.005) and 16- to 18-year-old (16- to 18-year-old group vs 14- to 15-year-old group, OR 0.79, 95% CI 0.69-0.91, p = 0.0008) age groups. There was no difference in incidence between the 12- to 13-year-old and 16- to 18-year-old groups (16- to 18-year group vs 12- to 13-year group, OR 1.26, 95% CI 0.93-1.72, p = 0.15). There were also no differences in concussion severity or recovery between any groups.

CONCLUSIONS

This study found that concussion incidence was higher during mid-adolescence than early and late adolescence, suggesting a U-shaped relationship between age and concussion risk over the course of adolescence. Age had no independent effect on concussion severity or recovery in the 12- to 13-, 14- to 15-, and 16- to 18-year-old groups. Further analysis of the various age groups revealed that results may vary significantly with minor changes to groupings, which may explain the divergent results in the current literature on this topic. Thus, caution should be taken when interpreting the results of this and all similar studies, especially when groupings are based on convenience.

Use of acute cognitive symptom cluster to predict return-to-learn duration following a sport-related concussion

OBJECTIVE

Adolescents sustaining sport-related concussion often experience difficulties with the return-to-learn (RTL) process. Whereas the initial symptom burden has predicted prolonged RTL, no studies have established a relationship between acute cognitive symptoms and RTL duration. The authors sought to evaluate the relationship between initial cognitive symptoms and RTL duration.

METHODS

A retrospective single-institution cohort study of adolescent athletes aged 12-23 years who were evaluated within 5 days of a diagnosed sport-related concussion between November 2017 and October 2020 was conducted. Athletes missing cognitive symptom ratings and RTL data were excluded. The primary exposure variable was the Cognitive Symptom Ratio (CSR), defined as total cognitive symptom cluster score divided by total Post-Concussion Symptom Scale (PCSS) score from the initial clinic visit. Primary and secondary outcomes were time to RTL and total length of care, respectively. Multivariable Cox proportional hazards modeling was used to assess the effect of CSR on RTL duration.

RESULTS

Of 653 athletes evaluated within 5 days of injury, 346 patients were included in the final cohort. Athletes reported a median initial PCSS score of 21 (interquartile range [IQR] 6-37) and a median cognitive symptom score of 4 (IQR 0-9). Most patients endorsed some degree of difficulty concentrating (n = 212, 61.3%). The median CSR was 0.18 (IQR 0.00-0.27). On multivariable regression analysis, a higher CSR was associated with prolonged RTL duration (HR 0.30, 95% CI 0.13-0.69, p = 0.004). When initial PCSS score was added to the model, the previously significant association between CSR and RTL was no longer significant (HR 0.67, 95% CI 0.29-1.59, p = 0.367). When dichotomized based on frequency distribution, a higher proportion of patients with low CSR achieved RTL by 7 days postinjury (82.2% vs 69.9%, p = 0.007), a difference not seen at 14 days (92.2% vs 87.3%, p = 0.133).

CONCLUSIONS

An acute ratio of cognitive symptoms may predict patients at increased risk for prolonged RTL and those with normal PCSS scores who may experience difficulties once resuming school activities.

Adolescents with a concussion have altered brain network functional connectivity one month following injury when compared to adolescents with orthopedic injuries

Concussion is a mild traumatic brain injury (mTBI) with increasing prevalence among children and adolescents. Functional connectivity (FC) within and between the default mode network (DMN), central executive network (CEN) and salience network (SN) has been shown to be altered post-concussion. Few studies have investigated connectivity within and between these 3 networks following a pediatric concussion. The present study explored whether within and between-network FC differs between a pediatric concussion and orthopedic injury (OI) group aged 10-18. Participants underwent a resting-state functional magnetic resonance imaging (rs-fMRI) scan at 4 weeks post-injury. One-way ANCOVA analyses were conducted between groups with the seed-based FC of the 3 networks. A total of 55 concussion and 27 OI participants were included in the analyses. Increased within-network FC of the CEN and decreased between-network FC of the DMN-CEN was found in the concussion group when compared to the OI group. Secondary analyses using spherical SN regions of interest revealed increased within-network FC of the SN and increased between-network FC of the DMN-SN and CEN-SN in the concussion group when compared to the OI group. This study identified differential connectivity patterns following a pediatric concussion as compared to an OI 4 weeks post-injury. These differences indicate potential adaptive brain mechanisms that may provide insight into recovery trajectories and appropriate timing of treatment within the first month following a concussion.

Risk factors for prolonged recovery from concussion in young patients

Objectives

For young patients sustaining concussion, assessing recovery is vital in determining safe return to play. Identifying risk factors may aid clinicians in recognising patients at risk for prolonged recovery. The study objective is to identify risk factors for prolonged (>28 days) and extended (>90 days) recovery (defined as symptom duration) and analyse how these risk factors differ between the two groups.

Methods

We retrospectively analysed electronic health record data (n=4937) among patients aged 10–18 years collected at Nationwide Children’s Hospital Sports Medicine concussion clinics between 1 July 2012 and 30 June 2019. Data collected included patient demographics, comorbidities (eg, prior psychiatric diagnoses, prior concussions) and injury characteristics (eg, loss of consciousness, injury setting). We examined patient risk factors for prolonged (>28 days) and/or extended (>90 days) recovery using modified Poisson regression models.

Results

Factors associated with increased risk of prolonged recovery from concussion included prior concussions (adjusted risk ratio (ARR) 1.19, 95% CI 1.02 to 1.38) for two concussions (ARR 1.36, 95% CI 1.14 to 1.61), for >3, and higher initial symptom score (ARR 2.57, 95% CI 2.34 to 2.83) for postconcussion symptom (PCS) scores 21–60 (ARR 2.89, 95% CI 2.54 to 3.29), for PCS>60. Risk factors for extended recovery included history of concussion (ARR 1.50, 95% CI 1.09 to 2.06) for two concussions (ARR 1.75, 95% CI 1.17 to 2.62), for >3 and older age (15–18 years, ARR 1.11, 95% CI 1.05 to 1.18). Additionally, comorbid attention deficit hyperactivity disorder increased risk of prolonged recovery (ARR 1.14, 95% CI 1.01 to 1.29) while anxiety increased risk for extended recovery (ARR 1.47, 95% CI 1.10 to 1.95).

Conclusion

Overall, risk factors for prolonged recovery differ somewhat from risk factors for extended recovery. For patients who present to clinic with concussion, mental health is an important consideration which may impact the timeline for symptom recovery.

Early psychological symptoms predict concussion recovery time in middle and high school athletes

INTRODUCTION

Lingering concussion symptoms can negatively impact a child's well-being, yet variability in recovery is poorly understood. To aid detection of those at risk for prolonged symptom duration, we explored postconcussion mood and sleep symptoms as predictors of recovery time in adolescent athletes.

METHOD

We utilized analyses designed to control for potentially confounding variables, such as concussion severity indicators and premorbid psychiatric history. Participants included 393 adolescent athletes (aged 12-18 years) evaluated in outpatient concussion clinics within 2 weeks after injury. Provider-documented date of symptom resolution was obtained via medical record review. Survival analysis for recovery time was conducted in the total sample, and separately for males and females using prior medical history (psychiatric disorder, prior concussion), injury-related factors (loss of consciousness, post-traumatic amnesia [PTA], concussion symptom severity), and psychological symptoms (General Anxiety Disorder-7 Item Scale, Patient Health Questionnaire-8 Item Depression Scale, Pittsburgh Sleep Quality Index) collected at initial clinic visit.

RESULTS

PTA, concussion symptoms, and sleep quality were associated with recovery in the total sample (HRs = 0.64-0.99, ps < .05). When analyzed by sex, only concussion symptoms were associated with recovery for females (with females reporting greater symptom severity than males), while for males PTA and greater depression symptoms were significant predictors of recovery (HRs = 0.54-0.98, ps < .05).

CONCLUSIONS

These findings identified differences in symptom presentation between sexes, particularly for mood symptoms, and suggest that assessment of postconcussive symptoms is useful in helping to identify individuals at risk for longer recovery. Continued exploration of post-injury psychological difficulties in athletes is warranted for better concussion management.

Interdisciplinary Rehabilitation for Concussion Recovery (i-RECOveR): protocol of an investigator-blinded, randomised, case series with multiple baseline design to evaluate the feasibility and preliminary efficacy of a 12-week treatment for persistent post-concussion symptoms

BACKGROUND

Up to 25% of concussed individuals experience persistent post-concussion symptoms (PPCSs) which may interfere with the return to pre-injury activities and cause significant stress. Given that multiple etiological factors are thought to contribute to PPCSs, an interdisciplinary approach is recommended. This pilot study aims to primarily investigate the feasibility of a novel interdisciplinary treatment for PPCSs. Given this intervention is novel, uncertainty exists in terms of potential recruitment and retention rates, adverse events, and treatment adherence and fidelity. These factors will be explored to inform the feasibility of a phase-2 randomised controlled trial. Preliminary efficacy of this intervention will also be explored.

METHODS

Fifteen individuals with mild traumatic brain injury and PPCSs will receive up to 12 weeks of interdisciplinary treatments including psychology, physiotherapy, and medical interventions. Primary feasibility outcomes including data on recruitment and retention rates and treatment adherence will be explored descriptively. The cognitive therapy rating scale will be used to assess treatment fidelity. A single-case series with multiple baseline design will be used to explore preliminary efficacy. Participants will be randomly assigned to baseline phases of 2, 4, or 6 weeks. Regarding patient-centred secondary outcomes, the Rivermead Post-Concussion Symptoms Questionnaire will be assessed three times a week during baseline and treatment phases. Secondary outcomes also include measures of mood, sleep and fatigue, physical functioning, return to activity, and health-related quality of life. Patient-centred outcomes will be assessed at baseline, pretreatment, post-treatment, and one- and three-month follow-up. Thematic analysis of participant experiences will be explored through qualitative interviews.

DISCUSSION

Results from this trial will inform the feasibility and preliminary efficacy of this interdisciplinary concussion intervention and whether proceeding to a future definitive phase-2 randomised controlled trial is worthwhile. Understanding the end-user perspective of the treatment will also enable modifications to the treatment protocol for future trials to best suit the needs of individuals with PPCSs after mTBI. Outcomes from this trial can be directly translated into community rehabilitation programmes.

TRIAL REGISTRATION

ANZCTR, ACTRN12620001111965. Registered 27 October 2020, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=379118.

Effects of prior concussion on symptom severity and recovery time in acute youth concussion

OBJECTIVE

Many studies have identified factors associated with increased symptom burden and prolonged recovery after pediatric and adolescent concussion. Few have systematically examined the effects of prior concussion on these outcomes in patients with concussion due to any mechanism. An improved understanding of the short- and long-term effects of a multiple concussion history will improve counseling and management of this subgroup of patients.

METHODS

A retrospective review of adolescent and young adult acute concussion patients presenting to the multidisciplinary concussion clinic between 2018 and 2019 was conducted at a single center. Patient demographic data, medical history including prior concussion, initial symptom severity score (SSS), injury mechanisms, and recovery times were collected. Univariate and multivariable analyses were conducted to identify associations of history of prior concussion and patient and injury characteristics with symptom score and recovery time.

RESULTS

A total of 266 patients with an average age of 15.4 years (age range 13-27 years) were included. Prior concussion was reported in 35% of patients. The number of prior concussions per patient was not significantly associated with presenting symptom severity, recovery time, or recovery within 28 days. Male sex and sports-related concussion (SRC) were associated with lower presenting SSS and shorter recovery time on univariate but not multivariable analysis. However, compared to non-sport concussion mechanisms, SRC was associated with 2.3 times higher odds of recovery within 28 days (p = 0.04). A history of psychiatric disorders was associated with higher SSS in univariate analysis and longer recovery time in univariate and multivariable analyses. Multivariable log-linear regression also demonstrated 5 times lower odds of recovery within 28 days for those with a psychiatric history.

CONCLUSIONS

The results of this study demonstrated that an increasing number of prior concussions was associated with a trend toward higher presenting SSS after youth acute concussion but did not show a significant association with recovery time or delayed (> 28 days) recovery. Presence of psychiatric history was found to be significantly associated with longer recovery and lower odds of early (≤ 28 days) recovery. Future prospective, long-term, and systematic study is necessary to determine the optimal counseling and management of adolescent and young adult patients with a history of multiple concussions.

Chronic cerebral blood flow alterations in traumatic brain injury and sports-related concussions

PRIMARY OBJECTIVE

Traumatic brain injury (TBI) and sports-related concussion (SRC) may result in chronic functional and neuroanatomical changes. We tested the hypothesis that neuroimaging findings (cerebral blood flow (CBF), cortical thickness, and ¹H-magnetic resonance (MR) spectroscopy (MRS)) were associated to cognitive function, TBI severity, and sex.

RESEARCH DESIGN

Eleven controls, 12 athletes symptomatic following ≥3SRCs and 6 patients with moderate-severe TBI underwent MR scanning for evaluation of cortical thickness, brain metabolites (MRS), and CBF using pseudo-continuous arterial spin labeling (ASL). Cognitive screening was performed using the RBANS cognitive test battery.

MAIN OUTCOMES AND RESULTS

RBANS-index was impaired in both injury groups and correlated with the injury severity, although not with any neuroimaging parameter. Cortical thickness correlated with injury severity (p = 0.02), while neuronal density, using the MRS marker ((NAA+NAAG)/Cr, did not. On multivariate analysis, injury severity (p = 0.0003) and sex (p = 0.002) were associated with CBF. Patients with TBI had decreased gray (p = 0.02) and white matter (p = 0.02) CBF compared to controls. CBF was significantly lower in total gray, white matter and in 16 of the 20 gray matter brain regions in female but not male athletes when compared to female and male controls, respectively.

CONCLUSIONS

Injury severity correlated with CBF, cognitive function, and cortical thickness. CBF also correlated with sex and was reduced in female, not male, athletes. Chronic CBF changes may contribute to the persistent injury mechanisms in TBI and rSRC.

Eye Tracking Metrics Differences among Uninjured Adolescents and Those with Acute or Persistent Post-Concussion Symptoms

SIGNIFICANCE

Eye tracking assessments that include pupil metrics can supplement current clinical assessments of vision and autonomic dysfunction in concussed adolescents.

PURPOSE

This study aimed to explore the utility of a 220-second eye tracking assessment in distinguishing eye position, saccadic movement, and pupillary dynamics among uninjured adolescents, those with acute post-concussion symptoms (≤28 days since concussion), or those with persistent post-concussion symptoms (>28 days since concussion).

METHODS

Two hundred fifty-six eye tracking metrics across a prospective observational cohort of 180 uninjured adolescents recruited from a private suburban high school and 224 concussed adolescents, with acute or persistent symptoms, recruited from a tertiary care subspecialty concussion care program, 13 to 17 years old, from August 2017 to June 2021 were compared. Kruskal-Wallis tests were used, and Bonferroni corrections were applied to account for multiple comparisons and constructed receiver operating characteristic curves. Principal components analysis and regression models were applied to determine whether eye tracking metrics can augment clinical and demographic information in differentiating uninjured controls from concussed adolescents.

RESULTS

Two metrics of eye position were worse in those with concussion than uninjured adolescents, and only one metric was significantly different between acute cases and persistent cases. Concussed adolescents had larger left and right mean, median, minimum, and maximum pupil size than uninjured controls. Concussed adolescents had greater differences in mean, median, and variance of left and right pupil size. Twelve metrics distinguished female concussed participants from uninjured; only four were associated with concussion status in males. A logistic regression model including clinical and demographics data and transformed eye tracking metrics performed better in predicting concussion status than clinical and demographics data alone.

CONCLUSIONS

Objective eye tracking technology is capable of quickly identifying vision and pupillary disturbances after concussion, augmenting traditional clinical concussion assessments. These metrics may add to existing clinical practice for monitoring recovery in a heterogeneous adolescent concussion population.