A systematic review of pre-injury anxiety disorder and post-concussion outcomes in youth and young adult athletes.

Pre-injury anxiety disorder may be a risk factor for poor outcomes following sportsrelated concussion. A systematic review was performed to characterize the relationship between pre-injury anxiety disorder and post-concussion symptom presentation and recovery time after sports-related concussions among children, adolescents, and young adults. A PRISMA-compliant literature search was conducted in Ovid MEDLINE, PsycINFO, EMBASE, and Scopus for articles published up to 25 January 2024. The initial query yielded 1358 unique articles. Articles that analyzed the relationship between pre-injury anxiety disorder and post-concussion symptoms and recovery time were included. A final cohort of 11 articles was extracted, comprising a total of 8390 study participants, of whom 921 had a history of pre-injury anxiety disorder. Pre-injury anxiety disorder was associated with prolonged time to return to sports activity and an increased incidence of physical, emotional, cognitive, and sleep-related symptoms. While the results of this review suggest an association between pre-injury anxiety disorder and post-concussion symptoms and recovery time, future studies should be more stringent regarding standardized anxiety disorder definitions, longitudinal assessment of post-concussion symptoms, anxiety disorder subtypes, and anxiety treatment history.

Sex differences in postconcussive symptom reporting in those with history of concussion: Findings from the federal interagency traumatic brain injury research (FITBIR) database.

Objective: This study investigated influence of biological sex on postconcussive symptoms (PCS) following concussion using the Federal Interagency Traumatic Brain Injury Research (FITBIR) database. Method: All studies with publicly released data as of 4/7/21 that included both males and females, enough information to determine severity of injury consistent with concussion, a measure of PCS, and objective measures of neurocognitive functioning were used. This resulted in 6 studies with a total of 9890 participants (3206 females, 6684 males); 815 participants completed the Neurobehavioral Symptom Inventory (NSI), 471 completed the Rivermead Post-Concussion Symptoms Questionnaire (RPSQ), and 8604 completed the Sport Concussion Assessment Tool-3rd Edition (SCAT 3). Questionnaires were harmonized and the following symptom composite scores were computed: total score, somatic, cognitive, and affective. Data were analyzed using linear mixed-effects models. Results: Females endorsed higher total symptoms relative to males and that military personnel endorsed higher symptoms relative to civilians. Additionally, there was a small but significant interaction effect, such that female military personnel endorsed even higher symptoms than would be predicted by the main effects. Similar patterns were observed for somatic, cognitive, and affective symptom domains. Conclusions: Further understanding sex differences in PCS reporting is key to informing the most appropriate treatment options. Future work will need to examine whether sex differences in symptom reporting is due to sex differences in endorsement styles or genuine differences in symptom presentation, as well as the relationship between study population (e.g., military, civilian, sport) and sex on objective cognitive functioning and other functional outcomes.

Functional Neurological Disorder Presenting After Concussion: A Retrospective Case Series.

OBJECTIVE: Although a majority of individuals recover from a concussion within weeks of the index injury, a substantial minority of patients report persistent postconcussion symptoms. Some of these symptoms may reflect a diagnosis of functional neurological disorder (FND). The authors evaluated the relationship between persistent postconcussion symptoms and FND symptoms. METHODS: In this retrospective chart review, the authors characterized demographic and clinical information from 50 patients with a confirmed diagnosis of FND whose functional neurological symptoms started after a concussion. RESULTS: Patients who developed FND after a concussion had high rates of baseline risk factors for both persistent postconcussion symptoms and FND. After the concussive event, functional neurological symptoms presented abruptly or developed insidiously over time. Functional neurological symptoms ranged widely and included gait symptoms, seizures, speech and language symptoms, weakness, sensory symptoms, tremors, and vision and oculomotor symptoms. CONCLUSIONS: Functional neurological symptoms can arise after a concussion. FND should be considered in the differential diagnosis of individuals presenting with neurological symptoms beginning after a concussion. By failing to recognize functional symptoms, clinicians may inadvertently reinforce negative health-related beliefs regarding a patient's injured brain.

Different trajectories of post-concussive symptom subscales after pediatric mild traumatic brain injury: Data from a prospective longitudinal study.

PURPOSE: The aim of this study was to investigate the trajectory of parent-rated post-concussive symptoms (PCS), attentional performance and participation within 6 months in children after mild traumatic brain injury (mTBI). METHODS: For this prospective longitudinal study, we included data on 64 children after mTBI and 57 healthy control children (age 8-16 years). Parents rated PCS using the Post-Concussion Symptom Inventory (PCSI) immediately (T0), 1 week (T1), and 3-6 months after injury (T2). Attentional performance (alertness, selective and divided attention) was measured using the Test of Attentional Performance (TAP) at T1 and T2 and participation was measured using the Child and Adolescent Scale of Participation (CASP) at T2. RESULTS: Friedman tests showed different trajectories of PCS subscales over time: Compared to pre-injury level, the amount of somatic and cognitive PCS was still elevated at T1, while emotional PCS at T1 were already comparable to pre-injury level. The rating of sleep-related PCS at T2 was significantly elevated compared to the pre-injury rating. Quade ANCOVAs indicated group differences in PCS subscales between patients and controls at T1, but not at T2. Patients and controls showed a similar performance in tests of attention at T1 and T2, but parental rating of participation at school was significantly reduced. Although cognitive PCS and attention were not correlated, there were significantly negative Spearman correlations between participation at home and pre-injury and concurrent PCS at T2. CONCLUSIONS: Our data imply that sleep-related PCS are still elevated weeks after injury and are thus a target for interventions after mTBI.

Cognitive, Sleep-Arousal, Physical, and Affective Domain Scores on the Post-Concussion Symptom Scale: Added Utility in Detecting Symptom Elevations among Student-Athletes with a Remote History of Concussion.

OBJECTIVE: The evaluation of self-reported symptoms is a standard component of concussion assessment and management. Clinicians typically evaluate a total symptom severity score rather than scores corresponding to specific symptom domains (i.e., cognitive, sleep-arousal, physical, and affective symptoms). This study examined (i) whether elevations in specific symptom domains would be missed when interpreting only the total symptom severity score and (ii) if a single symptom domain elevation was more common than having elevated symptoms across multiple domains. METHOD: Adolescent student-athletes (N = 1,008) with concussion history (i.e., ≥6 months since last concussion) completed the Post-Concussion Symptom Scale (PCSS). The PCSS total score and cognitive, sleep-arousal, physical, and affective domain scores were calculated. To determine if symptoms were elevated, scores were compared to normative data matched on gender and pre-existing conditions, with scores considered elevated if they were ≥84th percentile. The frequency of total and domain score elevations were calculated and stratified by gender and number of prior concussions (i.e., 1 or ≥2 prior concussions). RESULTS: Overall, 26% of student-athletes had an elevated symptom domain score without being elevated on the total score. The most common symptom presentation was to have a single elevated symptom domain (21%), followed by two (11%), three (8%), or four elevated domains (6%). CONCLUSIONS: Interpreting PCSS symptom domains may be beneficial in detecting student-athletes with elevated symptoms following a remote concussion. Roughly a quarter of student-athletes have domain-specific symptom elevations that would be missed by interpreting the total score alone.

Gender Disparities in Neurobehavioral Symptoms and the Role of Post-Traumatic Symptoms in US Service Members Following Mild Traumatic Brain Injury.

Women are more directly involved in combat operations today than ever before, currently making up 18.6% of officers and 16.8% of enlisted personnel in the United States military. However, women continue to be under-represented in military research. Studies that do consider gender differences in traumatic brain injury (TBI) outcomes have shown that women report significantly more post-concussive symptoms than men. Conclusions for true gender differences related to TBI are hard to make without controlling for non-TBI factors. The effects previously identified in the literature may be an artifact of how men and women differ in their response to injury, unrelated to the neurological recovery process associated with TBI. The objective of this study was to examine the effects of gender specifics on mild TBI (mTBI) sequelae on injured and uninjured control groups, and to investigate the role of post-traumatic stress disorder (PTSD) on symptom reporting. It should be noted that the terms "gender" and "men/women" are used in this article in place of "sex" or "males/females" given that we are not discussing biological attributes. A total of 966 United States military service members and veterans were included in the study. Of the total sample, 455 men and 46 women were in the mTBI group, 285 men and 31 women were in the injured controls group (IC), and 111 men and 38 women in the non-injured controls group (NIC). Post-concussive and quality of life symptoms were compared for men and women while controlling for combat exposure. MTBI and IC groups were also stratified by PTSD presentation. Measures used included the Neurobehavioral Symptom Inventory (NSI), PTSD Checklist (PCL-C), Traumatic Brain Injury Quality of Life (TBI-QOL), and Combat Exposure Scale. In the mTBI group, women had worse scores on NSI total, NSI Somatosensory and Affective clusters, and the TBI-QOL Anxiety, Fatigue, and Headache scales (n2 = 0.018-0.032, small to small-medium effect sizes). When PTSD was present, women had worse scores on the NSI Somatosensory cluster only (n2 = 0.029, small-medium effect size). In contrast, when PTSD was absent, women had worse scores than men on the NSI Somatosensory and Affective clusters, and the TBI-QOL Anxiety and Headache scales (n2 = 0.032-0.063, small to medium effect sizes). In the IC group, women had worse scores on the NSI Cognitive cluster and the TBI-QOL Fatigue and Pain Interference scales (n2 = 0.024-0.042, small to small-medium effect sizes). However, group differences were no longer found when stratified by PTSD sub-groups. In the NIC group, there were no significant group differences for any analyses. We were able to identify symptoms unique to women recovering from mTBI that were not present following other forms of physical injury or in healthy controls. However, the impact of PTSD exacerbates the symptom profile and its comorbidity with mTBI equates to most of the noted gender differences.

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

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

Prefrontal Cortex Activity During Gait in People With Persistent Symptoms After Concussion.

BACKGROUND: Concussions result in transient symptoms stemming from a cortical metabolic energy crisis. Though this metabolic energy crisis typically resolves in a month, symptoms can persist for years. The symptomatic period is associated with gait dysfunction, the cortical underpinnings of which are poorly understood. Quantifying prefrontal cortex (PFC) activity during gait may provide insight into post-concussion gait dysfunction. The purpose of this study was to explore the effects of persisting concussion symptoms on PFC activity during gait. We hypothesized that adults with persisting concussion symptoms would have greater PFC activity during gait than controls. Within the concussed group, we hypothesized that worse symptoms would relate to increased PFC activity during gait, and that increased PFC activity would relate to worse gait characteristics. METHODS: The Neurobehavior Symptom Inventory (NSI) characterized concussion symptoms. Functional near-infrared spectroscopy quantified PFC activity (relative concentration changes of oxygenated hemoglobin [HbO2]) in 14 people with a concussion and 25 controls. Gait was assessed using six inertial sensors in the concussion group. RESULTS: Average NSI total score was 26.4 (13.2). HbO2 was significantly higher (P = .007) for the concussed group (0.058 [0.108]) compared to the control group (-0.016 [0.057]). Within the concussion group, HbO2 correlated with NSI total symptom score (ρ = .62; P = .02), sagittal range of motion (r = .79; P = .001), and stride time variability (r = -.54; P = .046). CONCLUSION: These data suggest PFC activity relates to symptom severity and some gait characteristics in people with persistent concussion symptoms. Identifying the neurophysiological underpinnings to gait deficits post-concussion expands our knowledge of motor behavior deficits in people with persistent concussion symptoms.

Convergence insufficiency in patients with post-concussion syndrome is accompanied by a higher symptom load: a cross-sectional study.

OBJECTIVE: To estimate the prevalence of convergence insufficiency (CI) in adult patients with post-concussion syndrome and determine the impact of CI on symptom load. METHODS: Cross-sectional study of 103 patients with neurological symptoms 2-6 months after a concussion. Symptoms were assessed with the Rivermead Post Concussion Symptoms Questionnaire (RPQ), and CI was diagnosed using near point of convergence, vergence facility, and the Convergence Insufficiency Symptom Survey. The RPQ score for patients with and without CI was compared, and sensitivity, specificity, and area under the receiver operating characteristic curve for the two visually related RPQ questions as indicators of CI were calculated. RESULTS: The proportion of patients diagnosed with symptomatic CI was 20.4% (95% confidence interval: 13.1-29.5%). The RPQ score was significantly higher for patients with symptomatic CI both before (p = .01) and after removal of the two visually related questions in the RPQ-questionnaire (p = .03). The two visually related RPQ questions were unable to detect CI. CONCLUSION: In patients with post-concussion syndrome, the load of nonvisual symptoms is higher in the presence of CI. A prospective interventional study on CI is required to study the relationship between CI and other post-concussion symptoms.

Concussion symptom presentation and clinical recovery among pediatric athletes: comparing concussions sustained during school and summer months.

OBJECTIVE: We examined post-concussion symptom presentation, exercise, and sleep among pediatric athletes who sustained concussion during the school year vs. summer months. METHODS: We evaluated athletes 6-18 years old within 21-days of concussion. They reported symptoms (Health and Behavior Inventory), with cognitive/somatic domain sub-scores calculated, and indicated if they had exercised or experienced sleep problems since injury. We grouped patients by injury season: summer months (June-August) vs. school year (September-May). RESULTS: 350 patients (14.4 ± 2.4 years old; 37% female; initial visit 8.8 ± 5.3 days post-concussion) were seen for care: 24% sustained a concussion during summer months, 76% during the school year. Lower cognitive (median = 7 [IQR = 1, 15] vs. 9.5 [4, 17]; p = 0.01), but not somatic (7 [2.5, 11] vs. 8 [4, 13]; p = 0.06), HBI scores were observed for patients injured during the summer. Groups were similar in proportion exercising (16% vs 17%) and endorsing sleep problems (29% vs 31%). After adjustments, sustaining a concussion during the summer predicted total (ß=-3.43; 95%CI = -6.50, -0.36; p = 0.029) and cognitive (ß = -2.29; 95%CI = -4.22, -0.36; p = 0.02), but not somatic (ß=-1.46; 95%CI = -2.84, -0.08; p = 0.04), symptom severity. CONCLUSION: Pediatric patients with concussion may present with greater cognitive symptoms during the school year, compared to summer months.

The Sport Concussion Assessment Tool: A multidimensional symptom model for detecting elevated post-concussion symptoms.

Objective: Investigate whether a four-factor model of post-concussion symptoms (i.e. cognitive, physical, affective, and sleep-arousal) aids in identifying student-athletes with persistent concerns not reflected by a total symptom score. Method: Collegiate student-athletes (N = 32,066) from the Concussion Assessment Research and Education consortium completed the Sport Concussion Assessment Tool, 3rd edition Symptom Evaluation at baseline and two post-injury follow-ups (i.e. beginning RTP and 6-month). Confirmatory factor analysis was used to compare a one- and four-factor model of post-concussion symptoms. Normative reference data were compared across stratifications (e.g. sex, prior concussions, and number of pre-existing conditions) using Mann-Whitney U tests, and elevation rates (i.e. ≥84th percentile) for subscales and the total score were recorded. Results: The four-factor model fit well before and after injury (CFIs > .95). Greater symptom severity on the subscale and total scores was associated with female sex (ps<.001, r range: .07 to .14) and more pre-existing conditions (ps<.001, η2 range: .01 to .04), while having more prior concussions was only related to total symptom scores (ps<.001, η2<.01). After a concussion, a sizeable portion of student-athletes (i.e., RTP = 11.8%; 6-month = 8.3%) had subscale elevations despite no total score elevation. Physical subscale elevations at RTP were the most common (i.e., 11.9%), driven by head and neck pain. Conclusion: After a sport-related concussion, a four-factor symptom model can be used to assess persistent symptoms in collegiate student-athletes. Identifying athletes with domain-specific elevations may help clinicians identify areas for further assessment and, in some cases, personalized rehabilitation plans.

Emergency Department Risk Factors for Post-Concussion Syndrome After Mild Traumatic Brain Injury: A Systematic Review.

Approximately 16% of patients with mild traumatic brain injury (mTBI) develop a post-concussion syndrome (PCS) with persistent physical, neurological, and behavioral complaints. PCS has a great impact on a patient's quality of life, often decreases the ability to return to work, and henceforth has a great economic impact. Recent studies suggest that early treatment can greatly improve prognosis and prevent long-term effects in these patients. However, early recognition of patients at high risk of PCS remains difficult. The objective of this systematic review is to assess risk factors associated with the development of PCS, primarily aimed at the group of non-hospitalized patients who were seen with mTBI at the emergency department (ED). We searched PubMed/MEDLINE, Cochrane Library and EMBASE on September 23, 2022, for prospective studies that assessed the risk factors for the development of PCS. Exclusion criteria were: retrospective studies; > 20% computed tomography (CT) abnormalities, <18 years of age, follow-up <4 weeks, severe trauma, and study population <100 patients. The search strategy identified 1628 articles, of which 17 studies met eligibility criteria. Risk factors found in this systematic review are pre-existing psychiatric history, headache at the ED, neurological symptoms at the ED, female sex, CT abnormalities, pre-existent sleeping problems, and neck pain at the ED. This systematic review identified seven risk factors for development of PCS in patients with mTBI. Future research should assess if implementation of these risk factors into a risk stratification tool will assist the emergency physician in the identification of patients at high risk of PCS.

Optimizing the Combination of Common Clinical Concussion Batteries to Predict Persistent Postconcussion Symptoms in a Prospective Cohort of Concussed Youth.

BACKGROUND: Studies have evaluated individual factors associated with persistent postconcussion symptoms (PPCS) in youth concussion, but no study has combined individual elements of common concussion batteries with patient characteristics, comorbidities, and visio-vestibular deficits in assessing an optimal model to predict PPCS. PURPOSE: To determine the combination of elements from 4 commonly used clinical concussion batteries and known patient characteristics and comorbid risk factors that maximize the ability to predict PPCS. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: We enrolled 198 concussed participants-87 developed PPCS and 111 did not-aged 8 to 19 years assessed within 14 days of injury from a suburban high school and the concussion program of a tertiary care academic medical center. We defined PPCS as a Post-Concussion Symptom Inventory (PCSI) score at 28 days from injury of ≥3 points compared with the preinjury PCSI score-scaled for younger children. Predictors included the individual elements of the visio-vestibular examination (VVE), Sport Concussion Assessment Tool, 5th Edition (SCAT-5), King-Devick test, and PCSI, in addition to age, sex, concussion history, and migraine headache history. The individual elements of these tests were grouped into interpretable factors using sparse principal component analysis. The 12 resultant factors were combined into a logistic regression and ranked by frequency of inclusion into the combined optimal model, whose predictive performance was compared with the VVE, initial PCSI, and the current existing predictive model (the Predicting and Prevention Postconcussive Problems in Pediatrics (5P) prediction rule) using the area under the receiver operating characteristic curve (AUC). RESULTS: A cluster of 2 factors (SCAT-5/PCSI symptoms and VVE near point of convergence/accommodation) emerged. A model fit with these factors had an AUC of 0.805 (95% CI, 0.661-0.929). This was a higher AUC point estimate, with overlapping 95% CIs, compared with the PCSI (AUC, 0.773 [95% CI, 0.617-0.912]), VVE (AUC, 0.736 [95% CI, 0.569-0.878]), and 5P Prediction Rule (AUC, 0.728 [95% CI, 0.554-0.870]). CONCLUSION: Among commonly used clinical assessments for youth concussion, a combination of symptom burden and the vision component of the VVE has the potential to augment predictive power for PPCS over either current risk models or individual batteries.

Co-existence of depression and post-concussion syndrome one month after mild traumatic brain injury.

BACKGROUND: Previous studies suggest an association between Post-concussion syndrome (PCS) and depression, both highly prevalent after mTBI. OBJECTIVE: To assess the prevalence and risk-factors of depression among patients with PCS 1 month after mTBI. METHODS: We prospectively screened 372 mTBI patients admitted in two academic Emergency Departments between 2017 and 2019. One month after mTBI, we administered the Rivermead Post-concussion symptoms Questionnaire (RPQ) and the Patient Health Questionnaire (PHQ-9) questionnaires over the telephone. PCS and depression were defined by RPQ ≥ 12 and PHQ-9 ≥ 10. Multivariate multinomial regression identified baseline factors associated with PCS and depression. RESULTS: Two hundred and eight completed RPQ and PHQ-9. Forty-seven patients (22.5%) met criteria for PCS, among which 22 (46.8%) met criteria for depression (PCS+D+). Patients with PCS but without depression were less likely to present with an associated injury (Coefficient = -1.6, p = 0.047) and to report initial sadness (Coefficient = -2.5, p = 0.03). Initial sadness (Coefficient = -1.3, p = 0.047), associated injury (Coefficient = -1.9, p = 0.008), as well as initial nausea (Coefficient = -1.8, p = 0.002), and male sex (Coefficient = 1.8, p = 0.002), were associated with the absence of depression and PCS in comparison with PCS+D+ patients. CONCLUSION: Among patients with PCS 1 month after mTBI, those with depression are more likely to present with initial sadness and with an associated injury.

The association between symptom burden and processing speed and executive functioning at 4 and 12 weeks following pediatric concussion.

OBJECTIVES: Symptoms and cognition are both utilized as indicators of recovery following pediatric concussion, yet their interrelationship is not well understood. This study aimed to investigate: 1) the association of post-concussion symptom burden and cognitive outcomes (processing speed and executive functioning [EF]) at 4 and 12 weeks after pediatric concussion, and 2) the moderating effect of sex on this association. METHODS: This prospective, multicenter cohort study included participants aged 5.00-17.99 years with acute concussion presenting to four Emergency Departments of the Pediatric Emergency Research Canada network. Five processing speed and EF tasks and the Post-Concussion Symptom Inventory (PCSI; symptom burden, defined as the difference between post-injury and retrospective [pre-injury] scores) were administered at 4 and 12 weeks post-concussion. Generalized least squares models were conducted with task performances as dependent variables and PCSI and PCSI*sex interaction as the main predictors, with important pre-injury demographic and injury characteristics as covariates. RESULTS: 311 children (65.0% males; median age = 11.92 [IQR = 9.14-14.21 years]) were included in the analysis. After adjusting for covariates, higher symptom burden was associated with lower Backward Digit Span (χ2 = 9.85, p = .043) and Verbal Fluency scores (χ2 = 10.48, p = .033) across time points; these associations were not moderated by sex, ps ≥ .20. Symptom burden was not associated with performance on the Coding, Continuous Performance Test, and Color-Word Interference scores, ps ≥ .17. CONCLUSIONS: Higher symptom burden is associated with lower working memory and cognitive flexibility following pediatric concussion, yet these associations were not moderated by sex. Findings may inform concussion management by emphasizing the importance of multifaceted assessments of EF.

Lifetime Traumatic Brain Injury and Risk of Post-Concussive Symptoms in the Millennium Cohort Study.

Traumatic brain injury (TBI) is prevalent among active duty military service members, with studies reporting up to 23% experiencing at least one TBI, with 10-60% of service members reporting at least one subsequent repeat TBI. A TBI has been associated with an increased risk of cumulative effects and long-term neurobehavioral symptoms, impacting operational readiness in the short-term and overall health in the long term. The association between multiple TBI and post-concussive symptoms (PCS), however, defined as symptoms that follow a concussion or TBI, in the military has not been adequately examined. Previous studies in military populations are limited by methodological issues including small sample sizes, the use of non-probability sampling, or failure to include the total number of TBI. To overcome these limitations, we examined the association between the total lifetime number of TBI and total number of PCS among U.S. active duty military service members who participated in the Millennium Cohort Study. A secondary data analysis was conducted using the Millennium Cohort Study's 2014 survey (n = 28,263) responses on self-reported TBI and PCS (e.g., fatigue, restlessness, sleep disturbances, poor concentration, or memory loss). Zero-inflated negative binomial models calculated prevalence ratios (PRs) and 95% confidence intervals (CIs) for the unadjusted and adjusted associations between lifetime TBIs and PCS. A third of military participants reported experiencing one or more TBIs during their lifetime with 72% reporting at least one PCS. As the mean number of PCS increased, mean lifetime TBIs increased. The mean number of PCS by those with four or more TBI (4.63) was more than twice that of those with no lifetime TBI (2.28). One, two, three, and four or more TBI had 1.10 (95% CI: 1.06-1.15), 1.19 (95% CI: 1.14-1.25), 1.23 (95% CI: 1.17-1.30), and 1.30 times (95% CI: 1.24-1.37) higher prevalence of PCS, respectively. The prevalence of PCS was 2.4 (95% CI: 2.32-2.48) times higher in those with post-traumatic stress disorder than their counterparts. Active duty military service members with a history of TBI are more likely to have PCS than those with no history of TBI. These results suggest an elevated prevalence of PCS as the number of TBI increased. This highlights the need for robust, longitudinal studies that can establish a temporal relationship between repetitive TBI and incidence of PCS. These findings have practical relevance for designing both workplace safety prevention measures and treatment options regarding the effect on and from TBI among military personnel.

Post-Concussion Symptoms in Women With Head Injury Due to Intimate Partner Violence.

Limited research has examined the symptom sequelae of head injuries in women survivors of intimate partner violence (IPV), despite this community being at increased risk for neurotrauma due to partner abuse. The current study compared post-concussion symptom severity between women with and without IPV-related head injuries. Women were recruited from court jurisdictions in Kentucky, USA, after receiving a protective order for partner abuse. The sample included 268 women with no prior head injuries (age: M[standard deviation (SD)] = 31.8[9.8], 77.2% White) and 251 women with lifetime IPV-related head injuries (age: M[SD] = 31.8[9.8], 88.0% White). Women with IPV-related head injuries were slightly older (t = 2.46, p = 0.014) with lower education (χ2 = 5.81, p = 0.016), were more frequently unemployed (χ2 = 9.23, p = 0.002), and had a higher likelihood of residing in a rural setting (χ2 = 30.16, p < 0.001). Women with IPV-related head injuries were also more often White (χ2 = 10.47, p = 0.001), but this group difference was almost entirely related to rural versus urban residence. Women with IPV-related head injuries reported a higher severity of lifetime physical IPV (t = 7.27, p < 0.001, d = 0.64, 95% confidence interval [CI]: [.46, .82]) and sexual IPV (t = 4.65, p < 0.001, d = 0.41 [0.24, 0.59]). A three-factor model of post-concussion symptoms, inclusive of cognitive, physical, and emotional symptoms, fit well (χ2 = 368.99, p < 0.0001, comparative fit index [CFI] = 0.974, Tucker-Lewis index [TLI] = 0.968, root mean square error of approximation [RMSEA] = 0.079 [0.071, 0.087]), and showed evidence for strong measurement invariance across women with and without IPV-related head injuries. The subscale and total scores each had acceptable reliability: cognitive (ω = 0.88 [0.86, 0.90]), physical (ω = 0.74 [0.70, 0.77]), and emotional (ω = 0.88 [0.86, 0.89]), and total score (ω = 0.93 [0.92, 0.95]). Women with IPV-related head injuries reported all individual post-concussion symptoms at a significantly higher frequency, with medium group differences in cognitive (t = 7.57, p < 0.001, d = 0.67 [0.50, 0.85]) and physical symptoms (t = 7.73, p < 0.001, d = 0.68 [0.51, 0.86]) and large group differences in emotional (t = 8.51, p < 0.001, d = 0.75 [0.57, 0.93]) and total symptoms (t = 9.07, p < 0.001, d = 0.80 [0.62, 0.98]). All sociodemographic characteristics were independently associated with post-concussion symptoms, as were physical IPV (total score: r = 0.28 [0.19, 0.35], p < 0.001) and sexual IPV severity (total score: r = 0.22 [0.13, 0.30], p < 0.001). In hierarchical regression analyses, controlling for sociodemographic characteristics (i.e., age, race/ethnicity, education, unemployment, and rural/urban residence) and physical and sexual IPV severity, IPV-related head injury was independently significant and accounted for significant additional variance when predicting cognitive (ΔR2 = 0.05, p < 0.001), physical (ΔR2 = 0.03, p < 0.001), emotional (ΔR2 = 0.07, p < 0.001), and total symptoms (ΔR2 = 0.06, p < 0.001). Negative-binomial regression resulted in similar findings. This study demonstrates that multiple sociodemographic and IPV history variables are related to post-concussion symptom severity, but IPV-related head injury was independently associated with greater symptom severity. Women with IPV-related head injuries may be at increased risk for unaddressed health problems spanning cognitive, physical, and emotional domains. Future research is needed to psychometrically evaluate assessment instruments for this population and to assess efficacy of interventions to address their unique health care needs.

Temporal Changes in Fixational Eye Movements After Concussion in Adolescents and Adults: Preliminary Findings.

Concussions often involve ocular impairment and symptoms such as convergence insufficiency, accommodative insufficiency, blurred vision, diplopia, eye strain, and pain. Current clinical assessments of ocular function and symptoms rely on subjective symptom reporting and/or involve lengthy administration time. More objective, brief assessments of ocular function following concussion are warranted. The purpose of this study was to evaluate changes in fixational eye movements (FEMs) and their association with clinical outcomes including recovery time, symptoms, cognitive and vestibular/ocular motor impairment. Thirty-three athletes (13-27 years of age; 54.5% female) within 21 days of a diagnosed concussion participated in the study. A tracking scanning laser ophthalmoscope (TSLO) evaluated FEMs metrics during fixation on a center and corner target. Participants completed symptom (Post-Concussion Symptom Scale [PCSS]), cognitive (Immediate Post-concussion Assessment and Cognitive Testing [ImPACT], and Vestibular/Ocular Motor Screening (VOMS) evaluations. All measures were administered at the initial visit and following medical clearance, which was defined as clinical recovery. Changes in FEMs were calculated using paired-samples t tests. Linear regression (LR) models were used to evaluate the association of FEMs with clinical recovery. Pearson product-moment correlations were used to evaluate the associations among FEMs and clinical outcomes. On the center task, changes across time were supported for average microsaccade amplitude (p = 0.005; Cohen's d = 0.53), peak velocity of microsaccades (p = 0.01; d = 0.48), peak acceleration of microsaccades (p = 0.02; d = 0.48), duration of microsaccade (p < 0.001; d = 0.72), and drift vertical (p = 0.017; d = -0.154). The LR model for clinical recovery was significant (R2 = 0.37; p = 0.023) and retained average instantaneous drift amplitude (ß = 0.547) and peak acceleration of microsaccade (ß = 0.414). On the corner task, changes across time were supported for drift proportion (p = 0.03; d = 0.43). The LR model to predict clinical recovery was significant (R2 = 0.85; p = 0.004) and retained average amplitude of microsaccades (ß = 2.66), peak velocity of microsaccades (ß = -15.11), peak acceleration of microsaccades (ß = 12.56), drift horizontal (ß = 7.95), drift vertical (ß = 1.29), drift amplitude (ß = -8.34), drift proportion (ß = 0.584), instantaneous drift direction (ß = -0.26), and instantaneous drift amplitude (ß = 0.819). FEMs metrics were also associated with reports of nausea and performance within the domain of visual memory. The FEMs metric were also associated with PCSS, ImPACT, and VOMS clinical concussion outcomes, with the highest magnitude correlations between average saccade amplitude and VOMS symptoms of nausea and average instantaneous drift speed and ImPACT visual memory, respectively. FEMs metrics changed across time following concussion, were useful in predicting clinical recovery, and were correlated with clinical outcomes. FEMs measurements may provide objective data to augment clinical assessments and inform prognosis following this injury.

Evidence of Ongoing Cerebral Microstructural Reorganization in Children With Persisting Symptoms Following Mild Traumatic Brain Injury: A NODDI DTI Analysis.

Approximately 300-550 children per 100,000 sustain a mild traumatic brain injury (mTBI) each year, of whom ∼25-30% have long-term cognitive problems. Following mTBI, free water (FW) accumulation occurs in white matter (WM) tracts. Diffusion tensor imaging (DTI) can be used to investigate structural integrity following mTBI. Compared with conventional DTI, neurite orientation dispersion and density imaging (NODDI) orientation dispersion index (ODI) and fraction of isolated free water (FISO) metrics may allow a more advanced insight into microstructural damage following pediatric mTBI. In this longitudinal study, we used NODDI to explore whole-brain and tract-specific differences in ODI and FISO in children with persistent symptoms after mTBI (n = 80) and in children displaying clinical recovery (n = 32) at 1 and 2-3 months post-mTBI compared with healthy controls (HCs) (n = 21). Two-way repeated measures analysis of variance (ANOVA) and voxelwise two-sample t tests were conducted to compare whole-brain and tract-specific diffusion across groups. All results were corrected at positive false discovery rate (pFDR) <0.05. We also examined the association between NODDI metrics and clinical outcomes, using logistical regression to investigate the value of NODDI metrics in predicting future recovery from mTBI. Whole-brain ODI was significantly increased in symptomatic participants compared with HCs at both 1 and 2 months post-injury, where the uncinate fasciculus (UF) and inferior fronto-occipital fasciculus (IFOF) were particularly implicated. Using region of interest (ROI) analysis in significant WM, bilateral IFOF and UF voxels, symptomatic participants had the highest ODI in all ROIs. ODI was lower in asymptomatic participants, and HCs had the lowest ODI in all ROIs. No changes in FISO were found across groups or over time. WM ODI was moderately correlated with a higher youth-reported post-concussion symptom inventory (PCSI) score. With 87% predictive power, ODI (1 month post-injury) and clinical predictors (age, sex, PCSI score, attention scores) were a more sensitive predictor of recovery at 2-3 months post-injury than fractional anisotropy (FA) and clinical predictors, or clinical predictors alone. FISO could not predict recovery at 2-3 months post-injury. Therefore, we found that ODI was significantly increased in symptomatic children following mTBI compared with HCs at 1 month post-injury, and progressively decreased over time alongside clinical recovery. We found no significant differences in FISO between groups or over time. WM ODI at 1 month was a more sensitive predictor of clinical recovery at 2-3 months post-injury than FA, FISO, or clinical measures alone. Our results show evidence of ongoing microstructural reorganization or neuroinflammation between 1 and 2-3 months post-injury, further supporting delayed return to play in children who remain symptomatic. We recommend future research examining the clinical utility of NODDI following mTBI to predict recovery or persistence of post-concussion symptoms and thereby inform management of mTBI.

Acute psychological symptom profiles in high school football players following sport-related concussion.

OBJECTIVE: In a cohort of high school football athletes, the authors sought to 1) describe the proportion of those with acute psychological symptoms postconcussion, 2) determine predictors of more acute psychological symptoms postconcussion, and 3) determine if acute psychological symptoms impact recovery. METHODS: A retrospective cohort study of high school football athletes (14-18 years of age) who sustained a sport-related concussion between November 2017 and April 2022 and presented to a multidisciplinary concussion center was performed. Based on their Post-Concussion Symptom Scale (PCSS) scores at the initial clinic visit, their total psychological symptom cluster score was calculated by summing their scores for the four affective symptoms (irritability, sadness, nervousness, and feeling more emotional). The psychological symptom ratio was defined as the ratio of the psychological symptom cluster score to the total initial PCSS score. Primary outcomes included time to return to learn (RTL), symptom resolution, and return to play (RTP). Uni- and multivariable regression analyses were performed controlling for demographic factors, learning disabilities, attention-deficit/hyperactivity disorder, and personal and/or family history of psychological diagnoses and migraine. RESULTS: A total of 195 male football players (mean age 16.2 ± 1.2 years) were included in the study. About one-third of the sample (n = 70, 35.9%) reported at least one psychological symptom. Of these 70 athletes, their psychological symptom scores were 1 (10.3%), 2 (7.7%), and ≥ 3 (17.9%). Irritability was the most endorsed psychological symptom (25.1%), followed by nervousness (15.9%), feeling more emotional (12.8%), and sadness (11.8%). The multivariable regression model showed that a positive psychological history (B = 2.66, 95% CI 0.74-4.58, p = 0.007) and family psychological history (B = 2.43, 95% CI 0.98-3.88, p = 0.001) were significant predictors of a higher psychological symptom cluster score. Multivariable linear regression analysis showed that a higher psychological symptom cluster score was associated with a longer time to RTP (B = 1.22, 95% CI 0.17-2.264, p = 0.023) but not with time to symptom resolution or RTL. The psychological symptom ratio was not a significant predictor. CONCLUSIONS: In a cohort of male football players, 36% reported at least one psychological symptom, with irritability being most commonly reported. Athletes with a personal and/or family history of psychological disorders experienced more acute psychological symptoms following a sport-related concussion. A higher psychological symptom cluster score was associated with delayed time to RTP but not time to RTL or symptom resolution.