Time interval between concussions and symptom duration

American Headache Society white paper on treatment of post-traumatic headache from concussion in youth

OBJECTIVE

To provide healthcare professionals guidance on youth at risk for prolonged recovery and post-traumatic headache (PTH), and on pharmacologic and non-pharmacologic management of PTH due to concussion and mild traumatic brain injury.

BACKGROUND

Headache is the most common persistent post-concussive symptom affecting 8% of youth for >3 months after concussion. Over the past decade, many studies have explored the treatment of PTH in youth, but there are no established guidelines.

METHODS

This white paper is based on a synthesis of an updated systematic review of the literature on treatment of PTH and a narrative review of the literature on risk factors for prolonged recovery and health disparities. Results were interpreted by a group of expert providers in PTH in children and adolescents through collaboration of the PTH and pediatric special interest groups of the American Headache Society.

RESULTS

Factors that consistently were associated with prolonged recovery from concussion and persistent PTH included female sex, a high number of acute symptoms, and adolescent age. Social determinants of health also likely play an important role in PTH and deserve consideration in the clinical and research settings. A total of 33 studies met the criteria for inclusion in the systematic review of PTH treatment in youth, although most were retrospective and of fair-to-poor quality. Treatment strategies included acute and preventive pharmacologic management, procedures, neuro-modulatory devices, physical therapy, physical activity, and behavioral health support. A collaborative care approach that includes a thoughtful combination of these management strategies is likely most effective.

CONCLUSIONS

This white paper provides a roadmap for tailoring the treatment of PTH based on factors influencing prolonged headache, the timing of therapies, and therapies with the most evidence for treating PTH in youth. We also highlight research needed for developing more definitive guidelines on PTH management in youth.

Confidence to Return to Play After Concussion

CONTEXT

The sequelae of concussion may have psychological consequences that affect an athlete's ability to return to play (RTP). However, confidence of RTP readiness is rarely monitored after a concussion.

DESIGN

This study examined the acute and longitudinal implications of concussion on an athlete's confidence to RTP, the relationship between self-reported symptoms and athlete confidence to RTP, and interactions between concussion symptoms, sex, sport type (contact vs noncontact), and confidence to RTP.

METHODS

Forty-six college athletes (65% female) sustained a concussion and completed the Injury Psychological Readiness to Return to Sport (I-PRRS) scale at 3 timepoints: within 72 hours of injury (acute), within 72 hours of beginning the RTP protocol (pre-RTP), and within 72 hours of being fully cleared to RTP (post-RTP).

RESULTS

Athletes reported acute low confidence after concussion (I-PRRS mean [SD] = 32.59 [18.45]), which improved over time (pre-RTP mean [SD] = 52.11 [9.60]; post-RTP mean [SD] = 57.45 [5.96]). Some athletes returned to competition (post-RTP) with lingering confidence concerns (ie, I-PRRS < 50; 95% CI = 0.03-0.26). Acute symptom severity was associated with worse confidence (P < .001). Sex and sport type (contact vs noncontact) had no relationship with confidence (P = .406, P = .3314, respectively). These results indicate that athletes lack confidence acutely (within 72 h) following concussion.

CONCLUSIONS

Although confidence improves over time, those who report greater acute symptoms also exhibit decreased confidence, and some athletes are returning to play with lingering concerns about their confidence (I-PRRS < 50). This preliminary evidence of heterogeneous confidence following concussion encourages the assessment and monitoring of confidence throughout concussion rehabilitation.

Influence of pre-existing conditions and concussion history on post-concussion symptom severity and recovery time in collegiate athletes

Mental health conditions and concussion history reported by a collegiate athlete may contribute to prolonged recovery and symptom severity after concussion. This work examined the potential associations among concussion history, pre-existing conditions, and sex relative to initial symptom severity and recovery duration following sport-related concussion (SRC) in a cohort of Division 1 NCAA athletes. This prospective cohort study analyzed symptom severity, recovery and return-to-play times reported post-SRC using data collected as part of the Pac-12 CARE Affiliated Program and Health Analytics Program. Health history questionnaires which included self-reported history of pre-existing conditions were completed at baseline. When consented athletes were diagnosed with a concussion, daily post-concussion symptom scores were evaluated until an athlete was clinically determined to be asymptomatic. Generalized linear and Cox proportional hazards models were used to determine associations between pre-existing conditions and recovery and return-to-play times. 92 concussions met inclusion criteria. Notable differences in initial symptom severity existed between females and males who had mood disorders ([Cohen's d] = 0.51) and ADHD (d = 0.93). The number of previous concussions was a strong predictor of athletes reporting pre-existing mood disorders, depression, anxiety, and ADHD (p = 0.008-0.04). Females with ≥2 previous concussions required more days to return-to-play than males (d = 0.31-0.72). Weekly recovery and return-to-play probabilities substantially differed between athletes that did or did not have learning disorders (HRRecovery = 0.32, HRRTP = 0.22, d = 1.96-2.30) and ADHD (HRRecovery = 3.38, HRRTP = 2.74, d = 1.71-4.14). Although no association existed between concussion history and acute symptom severity, collegiate athletes with a history of concussion had higher probabilities of reporting depression, mood disorders, anxiety, and ADHD. Having ADHD or learning disorders likely strongly affects time to recovery and return-to-play for collegiate athletes.

Examining Acute Symptoms After Sport-Related Concussion in Collegiate Athletes With Preinjury Migraines

OBJECTIVE

To examine whether a personal history of migraines is associated with worse acute symptom burden after sport-related concussion (SRC).

DESIGN

Retrospective cohort study.

SETTING

National Collegiate Athletic Association Division III collegiate programs.

PARTICIPANTS

Collegiate athletes from a prospective concussion surveillance system between 09, 2014, and 01, 2023.

INTERVENTION

Preinjury migraines (yes/no) were self-reported by athletes.

MAIN OUTCOME MEASURES

Post-Concussion Symptom Scale (PCSS) were collected within 3 days postinjury. Mann-Whitney U tests compared total PCSS scores and individual symptom scores between athletes with and without preinjury migraines. Chi-squared tests were used to compare proportions of athletes endorsing individual symptoms (ie, item score ≥1) between 2 groups. Multivariable regression analyzed potential predictors of PCSS scores.

RESULTS

Of 1190 athletes with SRC, 93 (7.8%) reported a preinjury history of migraines. No significant difference in total PCSS scores was found between athletes with and without preinjury migraines (22.0 ± 16.4 vs 20.5 ± 15.8, U = 48 719.0, P = 0.471). Athletes with preinjury migraines reported greater severity of "sensitivity to light" (1.59 ± 1.59 vs 1.23 ± 1.41, P = 0.040) and "feeling more emotional" (0.91 ± 1.27 vs 0.70 ± 1.30; P = 0.008) and were more likely to endorse "feeling more emotional" (45.2% vs 29.5%, P = 0.002). No differences were found across all other symptoms, including headaches (migraine = 87.1% vs no migraine = 86.3%, P = 0.835). In a multivariable model, a history of migraine was not a significant predictor of acute PCSS scores, but those with a history of psychological disorders (β = 0.12, P <0 .001) and greater number of days to symptom evaluation (β = 0.08, P = 0.005) had higher PCSS scores.

CONCLUSIONS

Collegiate athletes with a pre-existing history of migraines did not have higher acute symptom burden after SRC.

Posttraumatic stress symptoms in recovery from concussion

BACKGROUND

Previous literature suggests that lingering concussion symptoms may be influenced by psychological factors. The relationship of posttraumatic stress symptoms (PTSS) during recovery with pre-existing/injury related factors and concussion symptomology is not fully understood. Identification of factors contributing to symptoms of posttraumatic stress may provide guidance to improve treatment following concussion.

METHOD

This study included 287 participants (Male 40.42%, n = 116; Female 59.58%, n = 171) aged 13-75 years diagnosed with a recent concussion at one of the North Texas Concussion Registry (ConTex) specialty concussion clinic sites. Preinjury emotional history, injury related factors, and emotional state at time of initial evaluation were analyzed as predictors of post-traumatic stress symptoms (PCL-5) during recovery.

RESULTS

Sixty-one percent of participants endorsed at least one PTSS. Correlations were found between initial Sport Concussion Assessment Tool 5Ⓡ (SCAT5) total emotional symptom severity and screening measures for anxiety (GAD-7; r = .453, p < .001) and depression (PHQ-8; r = .550, p < .001) symptom scores. Of the measures from the initial visit included in the multiple regression model predicting severity of PTSS at follow-up (R2 = 0.554, β < .001), three measures predicted PTSS severity: initial SCAT5 total emotional symptom severity (β = 0.565, p < .001), PHQ-8 score (β =.166, p = .009), and GAD-7 score (β = 0.119, p = .044).

CONCLUSIONS

Symptoms of anxiety and depression along with specific SCAT5 emotional symptoms present at the time of initial evaluation may serve to predict overall level of PTSS and increased risk for PTSS during recovery. PTSS may be another dimension of response to injury and concussion recovery, with a large percentage of individuals endorsing at least one PTSS. Clinicians can utilize brief assessments such as the SCAT5 at the time of initial clinical evaluation to identify those at risk for PTSS following concussion.

The Interval Between Concussions Does Not Influence Time to Asymptomatic or Return to Play: A CARE Consortium Study

INTRODUCTION

The purpose of this study was to determine if the time interval between two concussive events influences the number of days to asymptomatic status, days to return to play, or performance on common post-concussion assessments following the second concussion.

METHODS

Data from 448 collegiate athletes and service academy cadets with two concussions (time between concussions: median 295.0 days [interquartile range: 125.0-438.2]), 40.0% female) were analyzed from Concussion Assessment Research and Education (CARE) Consortium institutions between 2014 and 2020. Days between concussions was the primary predictor variable. Primary outcome measures included time to asymptomatic and time to return to play following the second concussion. Secondary outcome measures included total number of symptoms, total symptom severity, Balance Error Scoring System total score, and Standardized Assessment of Concussion total score within 48 h of their second concussion.

RESULTS

Time between concussions did not significantly contribute to the multivariate time to asymptomatic (p = 0.390), time to return to play (p = 0.859), or the secondary outcomes (p-range = 0.165-0.477) models. Time to asymptomatic (p = 0.619) or return to play (p = 0.524) did not differ between same-season and different-season concussions. Sex significantly contributed to the return to play (p = 0.005) multivariate model. Delayed symptom onset and immediate removal from play/competition significantly contributed to the total number of symptoms (p = 0.001, p = 0.014) and symptom severity (p = 0.011, p = 0.022) multivariate models.

CONCLUSION

These results suggest that in a population with a large period between injuries, the time between concussions may not be relevant to clinical recovery.

Recovery After Sport-Related Concussion in Collegiate Athletes With Self-Reported Pre-Injury Migraines

Pre-injury migraines might be a risk factor for prolonged recovery after sport-related concussion (SRC). We sought to examine whether a pre-injury history of migraines is associated with worse recovery following SRC in collegiate athletes. Data were collected through a prospective concussion surveillance system in 11 National Collegiate Athletic Association (NCAA) Division III college athletic programs between September 2014 and March 2020. Our primary independent variable, pre-injury migraines, were self-reported by the athletes. Between those with and without migraines, the outcomes of days to return-to-learn (RTL) without academic accommodations and return-to-play (RTP) were compared using Mann-Whitney U tests. Each athlete's RTL and RTP status was dichotomized (i.e., returned vs. not returned) at various time points for RTL (i.e., 7/14/21/28 days) and RTP (i.e., 14/21/28/56 days). Chi-squared tests were performed to compare the proportions of RTL and RTP status between groups. Multivariable regressions analyzed potential predictors of RTL and RTP adjusting for age, gender, prior concussions, other health conditions, and symptom severity. Of 1409 athletes with an SRC, 111 (7.9%) had a pre-injury history of migraines. Compared with those without migraines, those with migraines had longer median (interquartile range [IQR]) days to RTL (migraines = 7.0 [3.0-12.3] vs. no migraines = 5.0 [2.0-10.0], U = 53,590.5, p = 0.022). No differences were found in RTP between the two groups (migraines = 16.0 [10.0-33.0] vs. nχo migraines 15.0 [11.0-23.0], U = 38,545.0, p = 0.408). Regarding RTL, significantly lower proportions of athletes in the migraine group had fully RTL, without accommodations, at ≤14 days (77.5% vs. 85.2%, χ2 = 4.33, p = 0.037), ≤21 days (85.3% vs. 93.0%, χ2 = 7.99, p = 0.005), and ≤28 days (88.2% vs. 95.6%, χ2 = 10.60, p = 0.001). Regarding RTP, a significantly lower proportion of athletes in the migraine group RTP at ≤28 days (72.0% vs. 82.7%, χ2 = 5.40, p = 0.020) and ≤56 days (84.0% vs. 93.0%, χ2 = 8.19, p = 0.004). In a multivariable model predicting RTL that was adjusted for age, gender, acute concussion symptoms, and other health variables (e.g., attention-deficit/hyperactivity disorder [ADHD], history of mental health difficulties), pre-injury history of migraine was associated with longer RTL (β = 0.06, p = 0.030). In a multivariable model predicting RTP, pre-injury history of migraine was not associated with RTP (β = 0.04, p = 0.192). In collegiate athletes, pre-injury migraine history was independently associated with longer RTL but not RTP. When comparing the proportions of those with successful RTP by days, significantly lower proportions of those with migraines showed successful RTP at ≤28 days and ≤56 days. Futures studies should study the generalizability of our findings in other school levels.

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.

Association of Premorbid Anxiety and Depression Symptoms in Concussion Recovery in Collegiate Student-Athletes

BACKGROUND

Mental health disorders are linked to prolonged concussion symptoms. However, the association of premorbid anxiety/depression symptoms with postconcussion return-to-play timelines and total symptom burden is unclear.

OBJECTIVE

To examine the association of self-reported premorbid anxiety/depression symptoms in collegiate student-athletes with (1) recovery times until asymptomatic, (2) return-to-play, and (3) postconcussion symptom burden.

STUDY DESIGN

Athletes in the Concussion Assessment, Research and Education Consortium completed baseline concussion assessments (Sport Concussion Assessment Tool [SCAT3] and Brief Symptom Inventory-18 [BSI-18]). Athletes were tested postinjury at <6 hours, 24 to 48 hours, time of asymptomatic and start of return-to-play protocol, unrestricted return-to-play, and 6 months after injury. Injured athletes were categorized into 4 groups based on BSI-18 scores: (1) B-ANX, elevated anxiety symptoms only; (2) B-DEP, elevated depression symptoms only; (3) B-ANX&DEP, elevated anxiety and depression symptoms; and (4) B-NEITHER, no elevated anxiety or depression symptoms. Relationship between age, sex, BSI-18 group, SCAT3 total symptom and severity scores, and time to asymptomatic status and return-to-play was assessed with Pearson's chi-squared test and robust analysis of variance.

LEVEL OF EVIDENCE

Level 3.

RESULTS

Among 1329 athletes with 1352 concussions, no respondents had a self-reported premorbid diagnosis of anxiety/depression. There was no difference in time until asymptomatic or time until return-to-play between BSI-18 groups (P = 0.15 and P = 0.11, respectively). B-ANX, B-DEP, and B-ANX&DEP groups did not have higher total symptom or severity scores postinjury compared with the B-NEITHER group.

CONCLUSION

Baseline anxiety/depression symptoms in collegiate student-athletes without a mental health diagnosis are not associated with longer recovery times until asymptomatic, longer time to return-to-play, or higher postconcussion total symptom and severity scores compared with athletes without baseline symptoms.

CLINICAL RELEVANCE

Anxiety and depression symptoms without a clear mental health diagnosis should be considered differently from other comorbidities when discussing prolonged recovery in collegiate student-athletes.

Assessment of post-concussion emotional symptom load using PCSS and PROMIS instruments in pediatric patients

OBJECTIVES

The purpose of this study is to evaluate the utility of the Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety and depressive symptom domains in conjunction with the Post-Concussion Symptom Scale (PCSS)for identifying pediatric patients with emotional symptoms following a concussion, and to identify predictors of higher emotional symptom loads.

METHODS

We recruited English-speaking patients aged 8-17 years presenting to a tertiary-care concussion clinic from 2014 to 2018 (n = 458). Demographics and clinical data including PCSS, injury date, previous history of anxiety/depression, and Vestibular/Ocular-Motor Screen (VOMS) were collected from patients' electronic medical records. Participants completed surveys in the PROMISTM Pediatric Item Bank v1.1-Anxiety and Depressive Symptoms domains at their initial clinic visit. Multivariable linear regression identified predictors of higher emotional symptom loads.

RESULTS

Overall, 425 (92.8%) reported ≥1 emotional symptom on either PROMIS or PCSS. Predictors of higher emotional symptom loads were abnormal VOMS, female sex, history of anxiety or depression, and longer time since injury.

CONCLUSION

Our results suggest that adding PROMIS anxiety and depressive symptom surveys to pediatric concussion evaluations may identify more children with emotional symptoms, allowing clinicians to better direct post-concussion treatment and incorporate psychological support for patients if necessary. Future studies should examine whether earlier identification of emotional symptoms with these tools facilitates recovery and improves short- and/or long-term psychological outcomes in pediatric concussion.

Symptom presentation and evolution in the first 48 hours after injury are associated with return to play after concussion in elite Rugby Union

BACKGROUND

Return to play (RTP) in elite rugby is managed using a 6-stage graduated RTP protocol, which can result in clearance to play within 1 week of injury. We aimed to explore how symptom, cognitive, and balance presentation and evolution during concussion screens 2 h (head injury assessment (HIA) 2) and 48 h (HIA3) after injury were associated with time to RTP) to identify whether a more conservative graduated RTP may be appropriate.

METHODS

A retrospective cohort study was conducted in 380 concussed rugby players from elite men's rugby over 3 consecutive seasons. Players were classified as shorter or longer returns, depending on whether RTP occurred within 7 days (allowing them to be considered to play the match 1 week after injury) or longer than 8 days, respectively. Symptom, cognitive, and balance performance during screens was assessed relative to baseline (normal or abnormal) and to the preceding screen (improving or worsening). Associations between sub-test abnormalities and RTP time were explored using odds ratios (OR, longer vs. shorter). Median day absence was compared between players with abnormal or worsening results and those whose results were normal or improving.

RESULTS

Abnormal symptom results during screens 2 h and 48 h after concussion were associated with longer return time (HIA2: OR = 2.21, 95% confidence interval (95%CI): 1.39-3.50; HIA3: OR = 3.30, 95%CI: 1.89-5.75). Worsening symptom number or severity from the time of injury to 2 h and 48 h post-injury was associated with longer return (HIA2: OR = 2.49, 95%CI: 1.36-4.58; HIA3: OR = 3.34, 95%CI: 1.10-10.15. Median days absence was greater in players with abnormal symptom results at both HIA2 and HIA3. Cognitive and balance performance were not associated with longer return and did not affect median days absence.

CONCLUSION

Symptom presentation and evolution within 48 h of concussion were associated with longer RTP times. This may guide a more conservative approach to RTP, while still adhering to individualized concussion management principles.

Variables associated with days of school missed following concussion: results from the Sport Concussion Outcomes in PEdiatrics (SCOPE) study

OBJECTIVE

To understand factors associated with missed academic time after concussion to improve support for patients. Our goal was to assess patient-specific predictors of total school time lost after pediatric/adolescent concussion.

STUDY DESIGN

We performed a prospective cohort study of children and adolescents (8-18 years of age) seen within 14 days of concussion from seven pediatric medical centers across the United States. We collected outcomes via the Concussion Learning Assessment & School Survey (CLASS) and constructed a multivariable predictive model evaluating patient factors associated with school time loss.

RESULTS

167 patients participated (mean age = 14.5 ± 2.2 years; 46% female). Patients were assessed initially at 5.0 ± 3.0 days post-injury and had a final follow-up assessment 24.5 ± 20.0 days post-concussion. Participants missed a median of 2 days of school (IQR = 0.5-4), and 21% reported their grades dropped after concussion. Higher initial symptom severity rating (β = 0.06, 95% CI = 0.03-0.08, p < 0.001) and perception of grades dropping after concussion (β = 1.37, 95% CI = 0.28-2.45, p = 0.01) were significantly associated with more days of school time missed after concussion. Those who reported their grades dropping reported missing significantly more school (mean = 5.0, SD = 4.7 days missed of school) than those who reported their grades did not drop (mean = 2.2, SD = 2.6 days missed of school; p < 0.001; Cohen's d = 0.87).

CONCLUSIONS

Children and adolescents reported missing a median of 2 days of school following concussion, and more missed school time after a concussion was associated with more severe concussion symptoms and perception of grades dropping. These findings may support recommendations for minimal delays in return-to-learn after concussion.

Symptom resolution following a repeat concussion within the same athlete

INTRODUCTION

Repeat sport-related concussion (SRC) is anecdotally associated with prolonged recovery. Few studies have examined repeat concussion within the same athlete. We sought to explore differences in symptom burden and recovery outcomes in an individual athlete's initial and repeat SRC.

METHODS

A retrospective within-subject cohort study of athletes aged 12-23 years diagnosed with two separate SRCs from 11/2017-10/2020 was conducted. Primary outcomes were initial symptom severity and time-to-symptom-resolution. Secondary outcomes included return-to-learn (RTL) and return-to-play (RTP) duration.

RESULTS

Of 868 athletes seen, 47 athletes presented with repeat concussions. Median time between concussions was 244 days (IQR 136-395). Comparing initial to repeat concussion, no differences were observed in time-to-clinic (4.3 ± 7.3vs.3.7 ± 4.6 days, p = 0.56) or initial PCSS (26.2 ± 25.3 vs. 30.5 ± 24.1, p = 0.32). While a difference was observed in time-to-symptom resolution between initial/repeat concussion (21.2 ± 16.3 vs. 41.7 ± 86.0 days, p = 0.30), this did not reach statistical significance. No significant differences were observed in time-to-RTL (17.8 ± 60.6 vs. 6.0 ± 8.3 days, p = 0.26) and RTP (33.2 ± 44.1 vs. 29.4 ± 39.1 days, p = 0.75). Repeat concussion was not associated with symptom resolution on univariate (HR 1.64, 95% CI 0.96-2.78, p = 0.07) and multivariable (HR 0.85, 95% CI 0.49-1.46, p = 0.55) Cox regression.

CONCLUSION

No significant differences in symptom duration and RTP/RTL were seen between initial/repeat concussion.

The Role of Puberty and Sex on Brain Structure in Adolescents With Anxiety Following Concussion

BACKGROUND

Adolescence represents a window of vulnerability for developing psychological symptoms following concussion, especially in girls. Concussion-related lesions in emotion regulation circuits may help explain these symptoms. However, the contribution of sex and pubertal maturation remains unclear. Using the neurite density index (NDI) in emotion regulation tracts (left/right cingulum bundle [CB], forceps minor [FMIN], and left/right uncinate fasciculus), we sought to elucidate these relationships.

METHODS

No adolescent had a history of anxiety and/or depression. The Screen for Child Anxiety Related Emotional Disorders and Children's Depression Rating Scale were used at scan to assess anxiety and depressive symptoms in 55 concussed adolescents (41.8% girls) and 50 control adolescents with no current/history of concussion (44% girls). We evaluated if a mediation-moderation model including the NDI (mediation) and sex or pubertal status (moderation) could help explain this relationship.

RESULTS

Relative to control adolescents, concussed adolescents showed higher anxiety (p = .003) and lower NDI, with those at more advanced pubertal maturation showing greater abnormalities in 4 clusters: the left CB frontal (p = .002), right CB frontal (p = .011), FMIN left-sided (p = .003), and FMIN right-sided (p = .003). Across all concussed adolescents, lower NDI in the left CB frontal and FMIN left-sided clusters partially mediated the association between concussion and anxiety, with the CB being specific to female adolescents. These effects did not explain depressive symptoms.

CONCLUSIONS

Our findings indicate that lower NDI in the CB and FMIN may help explain anxiety following concussion and that adolescents at more advanced (vs less advanced) status of pubertal maturation may be more vulnerable to concussion-related injuries, especially in girls.

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.

Dose-Response Effect of Mental Health Diagnoses on Concussion Recovery in Children and Adolescents

BACKGROUND

Pre-existing mental health diagnoses may contribute to greater emotional symptom burden and prolonged recovery after concussion.

HYPOTHESIS

Youth with pre-existing mental health diagnoses will have greater emotional symptom burden, greater risk for delayed return to exercise, and more prolonged recovery from concussion than those without those diagnoses.

STUDY DESIGN

Prospective cohort.

LEVEL OF EVIDENCE

Level 3.

METHODS

A prospective registry of youth concussion was examined for differences in emotional symptom burden after injury to develop a predictive risk model for prolonged recovery. The impact of individual and total number of pre-existing mental health diagnoses (0, 1, 2, and 3+) was assessed, and multivariable logistic regression was performed to identify factors associated with prolonged recovery.

RESULTS

Among a cohort of 3105 youth with concussion, those with a history of mental health diagnoses, in a dose-response fashion, had greater postinjury emotional symptom burden (7 emotional symptoms vs 4; P < 0.01), visio-vestibular dysfunction (65% abnormal vs 56% abnormal; P < 0.01), later return to symptom-limited exercise (23 vs 21 days; P < 0.01), and overall longer concussion recovery (38 days, interquartile range [IQR] 18, 80) versus 25 days (IQR 13, 54; P < 0.01). Boys with prolonged recovery after concussion had greater emotional symptom burden than girls (5 emotional symptoms vs 3; P < 0.01).

CONCLUSION

Pre-existing mental health diagnoses are associated with greater postinjury emotional symptom burden and longer concussion recovery in a dose-response fashion. Visiovestibular deficits and delayed return to exercise are also associated with pre-existing mental health diagnoses and prolonged recovery. Boys with prolonged recovery from concussion experience greater emotional symptom burden than girls.

CLINICAL RELEVANCE

Addressing pre-existing mental health diagnoses is essential to concussion management. Boys with prolonged recovery from concussion may particularly benefit from interventions to address their higher emotional symptom burden. Interventions, including a home visio-vestibular exercise program and symptom-limited exercise, may contribute to improving time to concussion recovery.

Non-invasive fluid biomarkers in the diagnosis of mild traumatic brain injury (mTBI): a systematic review

BACKGROUND

Despite approximately 55.9 million annual mild traumatic brain injuries (mTBIs) worldwide, the accurate diagnosis of mTBI continues to challenge clinicians due to symptom ambiguity, reliance on subjective report and presentation variability. Non-invasive fluid biomarkers of mTBI offer a biological measure to diagnose and monitor mTBI without the need for blood draws or neuroimaging. The objective of this study is to systematically review the utility of such biomarkers to diagnose mTBI and predict disease progression.

METHODS

A systematic review performed in PubMed, Scopus, Cochrane and Web of Science followed by a manual search of references without a specified timeframe. Search strings were generated and run (27 June 2022) by a research librarian. Studies were included if they: (1) included human mTBI subjects, (2) assessed utility of a non-invasive biomarker and (3) published in English. Exclusion criteria were (1) non-mTBI subjects, (2) mTBI not assessed separately from moderate/severe TBI, (3) required intracranial haemorrhage or (4) solely assesses genetic susceptibility to mTBI.

RESULTS

A total of 29 studies from 27 subject populations (1268 mTBI subjects) passed the inclusion and exclusion criteria. Twelve biomarkers were studied. Salivary RNAs, including microRNA, were assessed in 11 studies. Cortisol and melatonin were assessed in four and three studies, respectively. Eight salivary and two urinary biomarkers contained diagnostic or disease monitoring capability.

DISCUSSION

This systematic review identified several salivary and urinary biomarkers that demonstrate the potential to be used as a diagnostic, prognostic and monitoring tool for mTBI. Further research should examine miRNA-based models for diagnostic and predictive utility in patients with mTBI.

PROSPERO REGISTRATION NUMBER

CRD42022329293.

Mild Traumatic Brain Injuries and Risk for Affective and Behavioral Disorders

OBJECTIVES

Recent studies document an association between mild traumatic brain injuries (mTBIs) in children and postinjury psychiatric disorders. However. these studies were subject to limitations in the design, lack of long-term follow-up, and poorly defined psychiatric outcomes. This study determines the incidence and relative risk of postinjury new affective and behavior disorders 4 years after mTBIs.

METHODS

A cohort study of mTBI cases and matched comparisons within an integrated health care system. The mTBI group included patients ≤17 years of age, diagnosed with mTBI from 2000 to 2014 (N = 18 917). Comparisons included 2 unexposed patients (N = 37 834) per each mTBI-exposed patient, randomly selected and matched for age, sex, race/ethnicity, and date of medical visit (reference date to mTBI injury). Outcomes included a diagnosis of affective or behavioral disorders in the 4 years after mTBI or the reference date.

RESULTS

Adjusted risks for affective disorders were significantly higher across the first 3 years after injury for the mTBI group, especially during the second year, with a 34% increase in risk. Adjusted risks for behavioral disorders were significant at years 2 and 4, with up to a 37% increase in risk. The age group with the highest risk for postinjury affective and behavioral disorders was 10- to 13-year-old patients.

CONCLUSIONS

Sustaining an mTBI significantly increased the risks of having a new affective or behavioral disorder up to 4 years after injury. Initial and ongoing screening for affective and behavior disorders following an mTBI can identify persistent conditions that may pose barriers to recovery.

Patterns and Predictors of Health Care Utilization After Pediatric Concussion: A Retrospective Cohort Study

OBJECTIVE

To characterize types, duration, and intensity of health care utilization following pediatric concussion and to identify risk factors for increased post-concussion utilization.

METHODS

A retrospective cohort study of children 5 to 17 years old diagnosed with acute concussion at a quaternary center pediatric emergency department or network of associated primary care clinics. Index concussion visits were identified using International Classification of Diseases, Tenth Revision, Clinical Modification codes. We analyzed patterns of health care visits 6 months before and after the index visit using interrupted time-series analyses. The primary outcome was prolonged concussion-related utilization, defined as having ≥1 follow-up visits with a concussion diagnosis more than 28 days after the index visit. We used logistic regressions to identify predictors of prolonged concussion-related utilization.

RESULTS

Eight hundred nineteen index visits (median [interquartile range] age, 14 [11-16] years; 395 [48.2%] female) were included. There was a spike in utilization during the first 28 days after the index visit compared to the pre-injury period. Premorbid headache/migraine disorder (adjusted odds ratio (aOR) 2.05, 95% confidence interval [CI] 1.09-3.89) and top quartile pre-injury utilization (aOR 1.90, 95% CI 1.02-3.52) predicted prolonged concussion-related utilization. Premorbid depression/anxiety (aOR 1.55, 95% CI 1.31-1.83) and top quartile pre-injury utilization (aOR 2.29, 95% CI 1.95-2.69) predicted increased utilization intensity.

CONCLUSIONS

Health care utilization is increased during the first 28 days after pediatric concussion. Children with premorbid headache/migraine disorders, premorbid depression/anxiety, and high baseline utilization are more likely to have increased post-injury health care utilization. This study will inform patient-centered treatment but may be limited by incomplete capture of post-injury utilization and generalizability.

Quality of Life Differences in Children and Adolescents With 0, 1 to 2, or 3+ Persistent Postconcussion Symptoms

CONTEXT

Persistent postconcussion symptoms (PPCSs) are associated with lower health-related quality of life (HRQoL) in children and adolescents. Despite commonly cited criteria for PPCSs involving 3 or more complaints, many individuals experience just 1 or 2 symptoms that may still negatively affect HRQoL.

OBJECTIVE

To determine differences in HRQoL between children and adolescents with 0, 1 to 2, or 3+ parent-reported persistent symptoms at 1 month postconcussion.

DESIGN

Prospective cohort study.

SETTING

Community practice clinics.

PATIENTS OR OTHER PARTICIPANTS

Individuals aged 8 to 18 years presented for the initial visit within 3 days of a sport- or recreation-related concussion. One month later, parents or guardians reported persistent symptoms using the Rivermead Post Concussion Symptoms Questionnaire (RPQ). Individuals with complete symptom data were analyzed (n = 236/245, n = 97 females, age = 14.3 ± 2.1 years). Participants were grouped by the number of discrete RPQ symptoms reported as worse than preinjury (0, 1-2, or 3+).

MAIN OUTCOME MEASURE(S)

Total summary and subscale scores on the Pediatric Quality of Life Inventory (PedsQL) 23-item HRQoL inventory and 18-item Multidimensional Fatigue Scale (MDFS).

RESULTS

Kruskal-Wallis rank sum tests highlighted differences in PedsQL HRQoL and MDFS total scores across symptom groups (PedsQL HRQoL: χ22 = 85.53, P < .001; MDFS: χ22 = 93.15, P < .001). Dunn post hoc analyses indicated all 3 groups were statistically significantly different from each other (P < .001). The median (interquartile range) values for the Peds QL Inventory HRQoL totals were 93.5 (84.2-98.8) for those with 0 symptoms; 84.8 (73.9-92.4) for those with 1 to 2 symptoms; and 70.7 (58.7-78.0) for those with 3+ symptoms. The median (interquartile range) values for the MDFS totals were 92.4 (76.4-98.6) for those with 0 symptoms; 78.5 (65.6-88.9) for those with 1 to 2 symptoms; and 54.2 (46.2-65.3) for those with 3+ symptoms. Similar group differences were observed for each PedsQL HRQoL and MDFS subscale score.

CONCLUSIONS

Children and adolescents whose parents reported 1 to 2 PPCSs had lower HRQoL and more fatigue than those with 0 symptoms. Across all 3 groups, those with 3+ persistent symptoms had the lowest HRQoL and most fatigue. These findings indicate the continued need for intervention in this age group to prevent and address PPCSs.

Functional Overlay Model of Persistent Post-Concussion Syndrome

Persistent post-concussion syndrome (PPCS) is a complex and debilitating condition that can develop after head concussions or mild traumatic brain injury (mTBI). PPCS is characterized by a wide range of symptoms, including headaches, dizziness, fatigue, cognitive deficits, and emotional changes, that can persist for months or even years after the initial injury. Despite extensive research, the underlying mechanisms of PPCS are still poorly understood; furthermore, there are limited resources to predict PPCS development in mTBI patients and no established treatment. Similar to PPCS, the etiology and pathogenesis of functional neurological disorders (FNDs) are not clear neither fully described. Nonspecific multifactorial interactions that were also seen in PPCS have been identified as possible predispositions for FND onset and progression. Thus, we aimed to describe a functional overlay model of PPCS that emphasizes the interplay between functional and structural factors in the development and perpetuation of PPCS symptoms. Our model suggests that the initial brain injury triggers a cascade of physiological and psychological processes that disrupt the normal functioning of the brain leading to persistent symptoms. This disruption can be compounded by pre-existing factors, such as genetics, prior injury, and psychological distress, which can increase the vulnerability to PPCS. Moreover, specific interventions, such as cognitive behavioral therapy, neurofeedback, and physical exercise can target the PPCS treatment approach. Thus, the functional overlay model of PPCS provides a new framework for understanding the complex nature of this condition and for developing more effective treatments. By identifying and targeting specific functional factors that contribute to PPCS symptoms, clinicians and researchers can improve the diagnosis, management, and ultimately, outcomes of patients with this condition.

Emotional Regulation and Adolescent Concussion: Overview and Role of Neuroimaging

Emotional dysregulation symptoms following a concussion are associated with an increased risk for emotional dysregulation disorders (e.g., depression and anxiety), especially in adolescents. However, predicting the emergence or worsening of emotional dysregulation symptoms after concussion and the extent to which this predates the onset of subsequent psychiatric morbidity after injury remains challenging. Although advanced neuroimaging techniques, such as functional magnetic resonance imaging and diffusion magnetic resonance imaging, have been used to detect and monitor concussion-related brain abnormalities in research settings, their clinical utility remains limited. In this narrative review, we have performed a comprehensive search of the available literature regarding emotional regulation, adolescent concussion, and advanced neuroimaging techniques in electronic databases (PubMed, Scopus, and Google Scholar). We highlight clinical evidence showing the heightened susceptibility of adolescents to experiencing emotional dysregulation symptoms following a concussion. Furthermore, we describe and provide empirical support for widely used magnetic resonance imaging modalities (i.e., functional and diffusion imaging), which are utilized to detect abnormalities in circuits responsible for emotional regulation. Additionally, we assess how these abnormalities relate to the emotional dysregulation symptoms often reported by adolescents post-injury. Yet, it remains to be determined if a progression of concussion-related abnormalities exists, especially in brain regions that undergo significant developmental changes during adolescence. We conclude that neuroimaging techniques hold potential as clinically useful tools for predicting and, ultimately, monitoring the treatment response to emotional dysregulation in adolescents following a concussion.

A Prospective Cohort Study of the Association Between Preinjury Psychosocial Function and Postconcussive Symptoms in Pediatric Mild Traumatic Brain Injury: An A-CAP Study

OBJECTIVE

We evaluated the moderating effect of preinjury psychosocial function on postconcussion symptoms for children with mild traumatic brain injury (mTBI).

DESIGN, SETTING, AND POPULATION

We conducted a prospective cohort study of children ages 8.0 to 16.9 years with mTBI ( n = 633) or orthopedic injury (OI; n = 334), recruited from 5 pediatric emergency departments from September 2016 to December 2018.

MAIN MEASURES

Participants completed baseline assessments within 48 hours of injury, and postconcussion symptoms assessments at 7 to 10 days, weekly to 3 months, and biweekly to 6 months post-injury. Preinjury psychosocial function was measured using parent ratings on the Pediatric Quality of Life Inventory (PedsQL) and the Strengths and Difficulties Questionnaire (SDQ), retrospectively evaluating their child's status prior to the injury. Parent and child ratings on the Health and Behavior Inventory (HBI) (cognitive and somatic subscales) and the Post-Concussion Symptom Interview (PCS-I) were used as measures of postconcussion symptoms. We fitted 6 longitudinal regression models, which included 747 to 764 participants, to evaluate potential interactions between preinjury psychosocial function and injury group as predictors of child- and parent-reported postconcussion symptoms.

RESULTS

Preinjury psychosocial function moderated group differences in postconcussion symptoms across the first 6 months post-injury. Higher emotional and conduct problems were significantly associated with more severe postconcussion symptoms among children with mTBI compared with OI. Wald's χ 2 for interaction terms (injury group × SDQ subscales) ranged from 6.3 to 10.6 ( P values <.001 to .043) across parent- and child-reported models. In contrast, larger group differences (mTBI > OI) in postconcussion symptoms were associated with milder hyperactivity (Wald's χ 2 : 15.3-43.0, all P < .001), milder peer problems (Wald's χ 2 : 11.51, P = .003), and higher social functioning (Wald's χ 2 : 12.435, P = .002).

CONCLUSIONS

Preinjury psychosocial function moderates postconcussion symptoms in pediatric mTBI, highlighting the importance of assessing preinjury psychosocial function in children with mTBI.

Back from the sideline, but back to baseline? A pediatric case study examining neuropsychological functioning after sustaining multiple sport-related concussions

Most individuals recover quickly from a concussion; however, youth who sustain multiple concussions may be at risk for long-term cognitive impairments. This case study examines the neuropsychological performance of a 13-year-old malewith five head injuries. After his first concussion during study participation (fourth injury overall), several improvements were observed, likely due to practice effects, yet after sustaining another concussion <2 years later,declines were observed in visuoconstruction, verbal memory, and intellectual functioning. Across serial re-evaluation, his vocabulary knowledge declined, and fewer improvements were observed than anticipated when accounting for serial practice effects, highlighting the possible cumulative impact of multiple concussions.

Disparities in Adherence to Concussion Clinical Care Recommendations in a Pediatric Population

OBJECTIVE

To characterize the relationship of sociodemographic factors to adherence to provider recommendations for pediatric concussion.

SETTING

Primary care (PC) practices within the Children's Hospital of Philadelphia network.

PARTICIPANTS

Patients aged 5 to 18 years old who presented to any PC site for concussion from September 26, 2019, to December 31, 2019.

DESIGN

Retrospective medical record review.

MAIN MEASURES

The primary outcome was adherence to follow-up recommendations as defined by (1) continued follow-up until provider clearance to return to full activity; (2) no more than 2 no-show visits; and (3) for those referred to specialty care (SC), attending at least 1 visit. We compared adherence by race/ethnicity, insurance, age, sex, injury mechanism, and repeat head injury using bivariate and multivariate analyses. A secondary outcome of referral to SC was compared by sociodemographic factors.

RESULTS

A total of 755 patients were included. Overall, 80.5% of the patients met adherence criteria. Following adjustment, non-Hispanic Black patients and publicly insured/self-pay patients were less likely to adhere to recommendations than non-Hispanic White patients (adjusted odds ratio [AOR] = 0.60; 95% CI, 0.37-1.00) and privately insured patients (AOR = 0.48; 95% CI, 0.30-0.75), respectively. When assessing differences in referral to SC, non-Hispanic Black patients and publicly insured/self-pay patients were more likely to receive a referral than their non-Hispanic White peers (OR = 1.56; 95% CI, 1.00-2.45) and privately insured patients (OR = 1.56; 95% CI, 1.05-2.32), respectively.

CONCLUSION

This study highlights disparities in adherence to concussion care recommendations, with non-Hispanic Black and publicly insured/self-pay patients less likely to adhere to follow-up recommendations than non-Hispanic White and privately insured patients, respectively. These disparities may impact recovery trajectories. Future studies should aim to identify specific individual- and system-level barriers preventing adherence to care in order to ultimately inform targeted interventions to achieve equity in care delivery and outcomes.

Documented Visio-Vestibular Examination and Anticipatory Guidance for Pediatric Concussion Patients

OBJECTIVES

Pediatric concussion patients are frequently managed in the primary care or acute care settings. Optimal care includes vision and vestibular assessments, as well as targeted anticipatory guidance for return to school and activity. We aimed to examine clinical practices related to the evaluation and management of concussion patients at children's hospital-based emergency department (ED) and primary care/urgent care settings.

METHODS

We conducted a retrospective chart review of children aged 5 to 18 years who presented to either the ED or the primary and urgent care settings during a 2-year period. We evaluated 2 concussion management practices: (1) completion of the visio-vestibular examination and (2) provision of anticipatory guidance and follow-up.

RESULTS

Among patients seen in the ED (n = 500), only 12.4% had at least 1 component of the visio-vestibular examination performed compared with 51.3% of patients (n = 78) in the primary and urgent care settings ( P < 0.05). Regarding anticipatory guidance, 86.2% of ED patients were advised to engage in cognitive rest, and 94.2% were told to physically rest compared with 67.9% and 72.8% in the primary and urgent care settings ( P < 0.05), respectively. Follow-up recommendations were provided similarly for both settings (92.0% in the ED and 85.9% in the primary/urgent care, P = 0.077).

CONCLUSIONS

Although most pediatric concussion patients receive instructions acutely about cognitive and physical rest, there is opportunity to increase the frequency of visio-vestibular testing in both the ED and the primary care settings. Future efforts should focus on strategies to consistently optimize visio-vestibular assessment given its value in concussion diagnosis.

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.

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.

Footwear Type and Testing Environment Do Not Affect Baseline Modified Balance Error Scoring System Performance Among Middle School Athletes

CONTEXT

Limited evidence exists to demonstrate the effect of extrinsic factors, such as footwear worn or the testing environment, on performance of the modified balance error scoring system (mBESS) in the middle school age (10-14 y) population. Therefore, the purpose of our study was to investigate the effect of footwear types and testing environments on performance of the mBESS by middle school athletes.

DESIGN

Cross-sectional.

METHODS

In total, 2667 middle school athletes (55.9% boys and 44.1% girls; age = 12.3 [0.94] y) were administered the mBESS while wearing their self-selected footwear (barefoot, cleats, or shoes) either indoors (basketball court) or outdoors (football field or track). The number of errors committed (range = 0-10) during the double-leg, single-leg, and tandem stances of the mBESS were summed to calculate a total score (range = 0-30). Kruskal-Wallis tests were used to assess for differences among the footwear groups for each mBESS stance and the total score. Mann-Whitney U tests with calculated nonparametric effect sizes (r) were used to assess for differences between the footwear groups and testing environments when appropriate.

RESULTS

There were significant differences for the number of committed errors among the footwear groups in the single-leg (P < .001) and tandem (P < .001) stances of the mBESS and mBESS total scores (P < .001). Significantly fewer errors (better) were committed while wearing shoes compared with other footwear in the single-leg and tandem stances of the mBESS (Ps ≤ .032, r = .07-.13). Participants assessed indoors committed significantly fewer errors than those assessed outdoors in each stance of the mBESS (Ps ≤ .022, r = .04-.14). Lower (better) mBESS total scores were observed for participants while wearing shoes (Ps ≤ .002, r = .10-.15) or assessed indoors (P = .001, r = .14).

CONCLUSIONS

Although our data suggest that the type of footwear worn and the testing environment have a significant effect on mBESS scores of middle school athletes, the magnitudes of these differences are negligible.

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.

The effect of birth order on length of hospitalization for pediatric traumatic brain injury: an analysis of the 1987 Finnish birth cohort

Purpose

This study examines the relationship between birth order and length of hospitalization due to pediatric traumatic brain injury (TBI).

Methods

We prospectively followed 59,469 Finnish newborns from 1987 until age 18 years. Data on first diagnosis of TBI was recorded within the 1987 Finnish Birth Cohort (FBC). Hospitalization period was divided into two categories: 2 days or less and more than 2 days. The latter was considered in this study as longer hospitalization.

Results

Compared with first born siblings, later born siblings had an increased risk of a longer hospitalization for TBI (12.7% of fourth or higher born birth children diagnosed with TBI were hospitalized for 2 or more days, 11.3% of first born, 10.4% of third born and 9.0% of second born). Fourth or higher born children were more likely to experience a repeat TBI; 13.4% of fourth or higher born children diagnosed with TBI had 2–3 TBIs during the study period compared to 9% of third born, 7.8% of second born and 8.8% of the first born. Injuries in the traffic environment and falls were the most common contributors to pediatric TBI and occurred most frequently in the fourth or higher birth category; 29.3% of TBIs among fourth or higher birth order were due to transport accidents and 21% were due to falls.

Conclusions

This study revealed a significant increase in risk for longer hospitalization due to TBI among later born children within the same sibling group. The study provides epidemiological evidence on birth order as it relates to TBI, and its potential to help to explain some of the statistical variability in pediatric TBI hospitalization over time in this population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-022-00919-x.

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.

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.

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.

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.

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.

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.

Sex and gender differences in mild traumatic brain injury/concussion

The high incidence of concussions/mild traumatic brain injury and the significant number of people with persisting concussion symptoms as well as the concern for delayed, neurodegenerative effects of concussions makes them a major public health concern. There is much to learn on concussions with respect to pathophysiology as well as vulnerability and resiliency factors. The heterogeneity in outcome after a concussion warrants a more personalized approach to better understand the biological and psychosocial factors that may affect outcome. In this chapter we address biological sex and gender as they impact different aspects of concussion including incidence, risk factors and outcome. As well, this chapter will provide a more fulsome overview of intimate partner violence, an often-overlooked cause of concussion in women. Applying the sex and gender lens to concussion/mild traumatic brain injury is imperative for discovery of its pathophysiology and moving closer to treatments.

Effect of Sleep-Related Symptoms on Recovery From a Sport-Related Concussion

Background

Sleep issues are commonly reported in athletes after a sport-related concussion (SRC). Further studies are needed to evaluate screening methods for sleep disturbances and the risk of persisting symptoms after an SRC.

Purpose

To evaluate the association between the Sport Concussion Assessment Tool 5 (SCAT5) symptoms of trouble falling asleep, fatigue (or low energy), and drowsiness and the risk of persisting symptoms (≥28 days to recovery) in adolescent athletes.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 519 athletes aged 13 to 18 years reported any sleep-related symptoms with an SRC, scored as none (0), mild (1-2), moderate (3-4), or severe (5-6), at their initial office visit (median, 5.4 days after an SRC). Scores were correlated with the risk of persisting symptoms. A composite "sleep cluster" score (range, 0-18) was calculated by summing the SCAT5 component items for trouble falling asleep, fatigue, and drowsiness.

Results

The results indicated that, compared with athletes who reported that they did not have each symptom, (1) athletes who reported mild, moderate, or severe trouble falling asleep were 3.0, 4.6, and 6.7 times more likely to have persisting symptoms, respectively; (2) athletes reporting mild, moderate, or severe fatigue (or low energy) were 2.6, 4.8, and 7.6 times more likely to have persisting symptoms, respectively; and (3) athletes reporting mild, moderate, or severe drowsiness were 1.9, 4.6, and 6.8 times more likely to have persisting symptoms, respectively (P < .001 for all). For every 1-point increase in the sleep cluster score, there was a 1.2-fold increased risk of persisting symptoms and an additional 2.4 days of recovery required (P < .001 for both).

Conclusion

Athletes who reported mild, moderate, or severe sleep-related symptoms on the SCAT5 were at a proportionally increased risk of persisting symptoms at the initial office visit.

Classification Criteria and Rates of Persistent Postconcussive Symptoms in Children: A Systematic Review and Meta-Analysis

OBJECTIVE

To provide a systematic review of studies examining the proportion of children with persistent postconcussive symptoms (PPCS) and to examine potential moderators of prevalence.

STUDY DESIGN

Searches were conducted in MEDLINE, Embase, PsycINFO, Scopus, and Cochrane Central Register of Controlled Trials on April 16, 2020. Criteria for study inclusion were children aged <18 years with concussion or mild traumatic brain injury, operational definition of PPCS, assessment of postconcussive symptoms at least 4 weeks postinjury, sample sizes and proportion with PPCS available, and study published in English. Definition of PPCS, sample size, proportion of participants identified with PPCS, child sex and age at injury, time postinjury, premorbid symptoms, diagnosis (concussion or mild traumatic brain injury), and study publication year were extracted from each article. Study quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

Thirteen studies, with a total of 5307 participants, were included in our analysis. The proportion of children identified with PPCS was 35.1% (weighted average; 95% CI, 26.3%-45.0%). The prevalence of PPCS was higher in older and female children who presented for care at concussion clinics, and in more recent publications.

CONCLUSIONS

Approximately one-third of children with concussion/mild traumatic brain injury will experience PPCS. Age, sex, and point of care could help identify children at high risk for PPCS.

Systematic Review of Pre-injury Migraines as a Vulnerability Factor for Worse Outcome Following Sport-Related Concussion

Background

Individuals with migraine disorders may be affected differently by concussions compared to individuals without migraine disorders. Prior studies on this topic have had mixed results. The purpose of this study was to systematically examine clinical outcomes following a sport-related concussion in athletes who have a pre-injury history of migraines.

Methods

All studies published prior to 15 May 2021 that examined pre-injury migraines as a possible predictor of clinical recovery from concussion were included. The search included (i) sport/athlete-related terms, (ii) concussion-related terms, and (iii) diverse predictor/modifier terms. After removing duplicates, 5,118 abstracts were screened, 538 full-text articles were reviewed, and 27 articles were included for narrative synthesis without meta-analysis (n = 25 with unique samples). Risk of bias was assessed using the domain-based Quality In Prognosis Studies (QUIPS) tool.

Results

Most studies did not find pre-injury migraines to be associated with concussion outcome, but several of these studies had small or very small sample sizes, as well as other methodological weaknesses. Risk of bias varied greatly across studies. Some of the larger, better-designed studies suggested pre-injury migraines may be a risk factor for worse concussion outcome. Most articles examined pre-injury migraines as an exploratory/secondary predictor of concussion outcome; very few were designed to examine migraine as the primary focus of the study. Migraine history was predominantly based on self-report and studies included minimal information about migraine (e.g., age of onset, frequency/severity, past treatment). Effect sizes were usually not reported or able to be calculated from reported study data.

Conclusion

There is some evidence to suggest that pre-injury migraines may be a vulnerability factor for a worse outcome following concussion, with studies having the lowest risk of bias reporting a positive association. Future studies should focus on improving methodological quality when assessing the relationship between pre-injury migraines and concussion outcome and better characterizing pre-injury migraine status.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42019128292, identifier: PROSPERO 2019 CRD42019128292.

Attention-Deficit/Hyperactivity Disorder-Related Self-Reported Symptoms Are Associated With Elevated Concussion Symptomatology

The aim of the present investigation was to provide insight into how postconcussion symptomatology may be altered in individuals exhibiting attention-deficit/hyperactivity disorder (ADHD)-related behaviors and examine factors that may be responsible for driving such relationships. A total of 99 individuals were assessed during the subacute phase of concussion recovery. Inattentive symptomatology, but not diagnosis of ADHD, was related to greater concussion-symptom severity and overall symptoms endorsed. Cluster and factor analyses highlighted that the relationship between ADHD symptomatology and concussion symptomatology was not a function of overlapping constructs being assessed (i.e., concussion-related symptomatology was not a proxy of ADHD-related symptomatology). These relationships were not mediated by parental observations of impairments in behaviors associated with executive functioning (i.e., executive dysfunction was not driving the greater concussion-related symptomatology associated with ADHD-related symptomatology). These findings highlight the importance of moving beyond categorical frameworks of ADHD to, instead, consider the continuum of underlying behaviors.

Paediatric post-concussive symptoms: symptom clusters and clinical phenotypes

OBJECTIVE

To assess the co-occurrence and clustering of post-concussive symptoms in children, and to identify distinct patient phenotypes based on symptom type and severity.

METHODS

We performed a secondary analysis of the prospective, multicentre Predicting and Preventing Post-concussive Problems in Pediatrics (5P) cohort study, evaluating children 5-17 years of age presenting within 48 hours of an acute concussion. Our primary outcome was the simultaneous occurrence of two or more persistent post-concussive symptoms on the Post-Concussion Symptom Inventory at 28 days post-injury. Analyses of symptom and patient clusters were performed using hierarchical cluster analyses of symptom severity ratings.

RESULTS

3063 patients from the parent 5P study were included. Median age was 12.1 years (IQR: 9.2-14.6 years), and 1857 (60.6%) were male. Fatigue was the most common persistent symptom (21.7%), with headache the most commonly reported co-occurring symptom among patients with fatigue (55%; 363/662). Headache was common in children reporting any of the 12 other symptoms (range: 54%-72%). Physical symptoms occurred in two distinct clusters: vestibular-ocular and headache. Emotional and cognitive symptoms occurred together more frequently and with higher severity than physical symptoms. Fatigue was more strongly associated with cognitive and emotional symptoms than physical symptoms. We identified five patient groups (resolved/minimal, mild, moderate, severe and profound) based on symptom type and severity.

CONCLUSION

Post-concussive symptoms in children occur in distinct clusters, facilitating the identification of distinct patient phenotypes based on symptom type and severity. Care of children post-concussion must be comprehensive, with systems designed to identify and treat distinct post-concussion phenotypes.While I agree with the use of the british spelling of Paediatric throughout, this groups actual name is with the American English Spelling.

Concussion Referral and Practice Patterns by Pediatric Emergency Medicine Providers

OBJECTIVES

Concussion is a commonly encountered diagnosis for pediatric emergency medicine (PEM) providers, yet little is known regarding referral patterns to specialists. Our goal was to assess PEM providers' referral patterns and current usage of standardized evaluation tools.

METHODS

This study was conducted as cross-sectional survey of PEM providers recruited from the American Academy of Pediatrics Section on Emergency Medicine Listserv. Surveys were distributed at 3 time points between December 1, 2020, and February 28, 2021, and included multiple choice, Likert scale, and free text questions. Descriptive statistics and bivariate analyses were used to describe the sample and compare responses between those with variable experience and confidence in concussion management.

RESULTS

In total, 162 of 491 Listserv members (33.0%) completed the survey. The factors most often reported to assist in referral decisions were history of severe (92.6%) or multiple (90.7%) prior concussions, prolonged symptom duration (89.5%), and severity of current symptoms (84.6%). Most providers reported having large experience (63.0%) and confidence (54.9%) in managing concussion. Standardized symptom scales (8.0%), vestibular (11.7%) and balance assessments (13.0%), and prognostic tools (6.8%) were infrequently used. Most (64.2%) providers felt specialty referral was important. More than 80% reported high likelihood to use an accurate risk stratification tool to facilitate referral.

CONCLUSIONS

Although most PEM providers reported significant experience and confidence in managing pediatric concussion, standardized assessment tools were infrequently used. Most were likely to use a risk stratification tool to assist in specialty referral. Future studies should assess the ability of targeted referral strategies to improve recovery for concussed youth.

Factors Associated With Repeat Emergency Department Visits in a State-wide Cohort of Pediatric Patients With Mild Traumatic Brain Injury

OBJECTIVE

To describe demographic, injury, and clinical characteristics of pediatric patients treated in the ED for mild traumatic brain injury (mTBI), and to evaluate characteristics associated with mTBI-related return emergency department (ED) visit within 1 month of initial presentation.

METHODS

Retrospective cohort study from April 1, 2012, to September 30, 2017, of children 19 years or younger presenting to any Maryland ED for mTBI identified in the Maryland Health Services Cost Review Commission database using ICD-9/10 codes. Demographic, injury, and clinical characteristics of individuals were collected. The primary outcome was mTBI-related return ED visit within 4 weeks. Multiple logistic regression tested the associated of individual demographic, injury, and clinical characteristics with mTBI-related return ED visit.

RESULTS

There were 25,582 individuals who had an ED visit for mTBI, of which 717 (2.8%) returned to the ED within 4 weeks and 468 (1.8%) within 1 week with a mTBI-related diagnosis. In multivariable logistic regression analyses, public insurance (adjusted odds ratio [aOR], 1.44; 95% confidence interval [CI], 1.21-1.72) and female sex (aOR, 1.34; 95% CI, 1.15-1.56) were associated with increased odds of return to the ED within 4 weeks. Age younger than 2 years (aOR, 0.39; 95% CI, 0.21-0.72) was associated with decreased odds of return visit. There was a trend toward decreased odds of return patients receiving computed tomography head imaging (aOR, 0.86; 95% CI, 0.74-1.01).

CONCLUSIONS

Although return to the ED for mTBI-related complaints is uncommon, girls, older children, and publicly insured individuals may be at increased risk. Future targeted study may identify areas to improve access to appropriate longitudinal care and justify ED programs to better coordinate follow-up for mTBI.

Learning and Attention Deficit/Hyperactivity Disorders as Risk Factors for Prolonged Concussion Recovery in Children and Adolescents

OBJECTIVE

Examine pre-existing learning disorders (LD) and attention deficit/hyperactivity disorders (ADHD) as risk factors for prolonged recovery and increased symptomology following pediatric mild traumatic brain injury (mTBI).

METHODS

We conducted a retrospective cohort study of children/adolescents (5-17 years) with mTBI who presented to a Children's Minnesota Concussion Clinic between April 2018 and March 2019. Differences across strata of pre-existing conditions (present vs. absent) in time to recovery measures were estimated via Kaplan-Meier and Cox proportional hazards analyses and differences in symptom trajectories were examined via linear mixed-effects regression models. Regression models were adjusted for age, sex and other confounders.

RESULTS

In our cohort of 680 mTBI patients, those with LD (n = 70) or ADHD (n = 107) experienced significantly longer median durations of symptoms (58 and 68 days, respectively) than those without (43 days). Accordingly, LD was significantly associated with delayed symptom recovery (adjusted hazard ratio (aHR) = 1.63, 95% CI: 1.16-2.29), return to school (1.47, 1.08-2.00), and return to physical activity (1.50, 1.10-2.04). Likewise, ADHD was associated with delayed recovery (1.69, 1.28-2.23), return to school (1.52, 1.17-1.97) and physical activity (1.55, 1.19-2.01). Further, patients with LD or ADHD reported, on average, significantly more concussion symptoms and higher vision symptom scores throughout recovery versus those without. There was no evidence that concussion or vision symptom recovery trajectories varied over time between those with/without LD or ADHD (joint P-interactions > 0.05).

CONCLUSION

Pre-existing LD and ADHD are risk factors for prolonged and more symptomatic mTBI recovery in youth. These results can inform clinical concussion management and recovery expectations.

Effect of Screen Time on Recovery From Concussion: A Randomized Clinical Trial

IMPORTANCE

There are limited data to guide screen time recommendations after concussion.

OBJECTIVE

To determine whether screen time in the first 48 hours after concussion has an effect on the duration of concussive symptoms.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was conducted in the pediatric and adult emergency departments of a tertiary medical center between June 2018 and February 2020. Participants included a convenience sample of patients aged 12 to 25 years presenting to the emergency department within 24 hours of sustaining a concussion. A total of 162 patients were approached, 22 patients met exclusion criteria, and 15 patients declined participation; 125 participants were enrolled and randomized.

INTERVENTIONS

Patients were either permitted to engage in screen time (screen time permitted group) or asked to abstain from screen time (screen time abstinent group) for 48 hours after injury.

MAIN OUTCOMES AND MEASURES

The primary outcome was days to resolution of symptoms, defined as a total Post-Concussive Symptom Scale (PCSS) score of 3 points or lower. Patients completed the PCSS, a 22-symptom scale that grades each symptom from 0 (not present) to 6 (severe), each day for 10 days. Kaplan-Meier curves and Cox regression modeling were used to compare the 2 groups. A Wilcoxon rank sum test was also performed among participants who completed the PCSS each day through recovery or conclusion of the study period.

RESULTS

Among 125 patients with concussion, the mean (SD) age was 17.0 (3.4) years; 64 participants (51.2%) were male. A total of 66 patients were randomized to the screen time permitted group, and 59 patients were randomized to the screen time abstinent group. The Cox regression model including the intervention group and the patient's self-identified sex demonstrated a significant effect of screen time (hazard ratio [HR], 0.51; 95% CI, 0.29-0.90), indicating that participants who engaged in screen time were less likely to recover during the study period. In total, 91 patients were included in the Wilcoxon rank sum test (47 patients from the screen time permitted group, and 44 patients from the screen time abstinent group). The screen time permitted group had a significantly longer median recovery time of 8.0 days (interquartile range [IQR], 3.0 to >10.0 days) compared with 3.5 days (IQR, 2.0 to >10.0 days; P = .03) in the screen time abstinent group. The screen time permitted group reported a median screen time of 630 minutes (IQR, 415-995 minutes) during the intervention period compared with 130 minutes (IQR, 61-275 minutes) in the screen time abstinent group.

CONCLUSIONS AND RELEVANCE

The findings of this study indicated that avoiding screen time during acute concussion recovery may shorten the duration of symptoms. A multicenter study would help to further assess the effect of screen time exposure.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03564210.

Using a Likelihood Heuristic to Summarize Conflicting Literature on Predictors of Clinical Outcome Following Sport-Related Concussion

OBJECTIVE

To introduce a new methodology for summarizing the results from systematic reviews-a likelihood heuristic-to the field of sport-related concussion.

DATA SOURCES

We applied the likelihood heuristic to the results of a systematic review published by Iverson et al (2017), containing 101 studies, on the predictors of worse clinical outcome following sport-related concussion.

STUDY SELECTION

We re-examined 5 individual prognostic factors that are of clinical interest and for which there is conflicting literature (female sex = 44 studies, prior concussion history = 41 studies, loss of consciousness = 31 studies, post-traumatic amnesia = 25 studies, and retrograde amnesia = 10 studies).

DATA EXTRACTION

For each prognostic factor, likelihood ratios were generated using the (1) number of significant and nonsignificant studies, (2) study power, (3) alpha level, and (4) prior probability that the alternative hypothesis was true.

DATA SYNTHESIS

Assuming each study had 80% power and an alpha level of 5%, observing the reported number of conflicting studies for female sex, prior concussion history, and retrograde amnesia is substantially more likely if each prognostic factor is associated with worse clinical outcome following sport-related concussion. For loss of consciousness, the observed number of conflicting studies is more likely if loss of consciousness is not associated with worse clinical outcome following sport-related concussion. A secondary analysis incorporating potentially more realistic study parameters of statistical power (45%) and alpha level (25%) generates weaker likelihood evidence that the observed numbers of studies for each prognostic factor are associated with worse clinical outcome following sport-related concussion than they are not.

CONCLUSIONS

Using a likelihood heuristic with 80% power and 5% alpha level, there is very strong likelihood evidence that female sex, prior concussion history, and retrograde amnesia are associated with worse clinical outcome following sport-related concussion. The strength of likelihood evidence that prognostic factors are associated with worse clinical outcome reduces when statistical power is lower and alpha level is inflated.

Participant factors that contribute to magnetic resonance imaging motion artifacts in children with mild traumatic brain injury or orthopedic injury

Motion can compromise image quality and confound results, especially in pediatric research. This study evaluated qualitative and quantitative approaches to motion artifacts detection and correction, and whether motion artifacts relate to injury history, age, or sex in children with mild traumatic brain injury or orthopedic injury relative to typically developing children. The concordance between qualitative and quantitative motion ratings was also examined. Children aged 8-16 years with mild traumatic brain injury (n = 141) or orthopedic injury (n = 73) were recruited from the emergency department and completed an MRI scan roughly 2 weeks post-injury. Typically developing children (n = 41) completed a single MRI scan. T1- and diffusion-weighted images were visually inspected and rated for motion artifacts by trained examiners. Quantitative estimates of motion artifacts were derived from FreeSurfer and FSL. Age (younger > older) and sex (boys > girls) were significantly associated with motion artifacts on both T1- and diffusion-weighted images. Children with mild traumatic brain or orthopedic injury had significantly more motion-corrupted diffusion-weighted volumes than typically developing children, but mild traumatic brain injury and orthopedic injury groups did not differ from each other. The exclusion of motion-corrupted volumes did not significantly change diffusion tensor imaging metrics. Results indicate that automated quantitative estimates of motion artifacts, which are less labour-intensive than manual methods, are appropriate. Results have implications for the reliability of structural MRI research and highlight the importance of considering motion artifacts in studies of pediatric mild traumatic brain injury.

The Known Unknowns: An Overview of the State of Blood-Based Protein Biomarkers of Mild Traumatic Brain Injury

Blood-based protein biomarkers have revolutionized several fields of medicine by enabling molecular level diagnosis, as well as monitoring disease progression and treatment efficacy. Traumatic brain injury (TBI) so far has benefitted only moderately from using protein biomarkers to improve injury outcome. Because of its complexity and dynamic nature, TBI, especially its most prevalent mild form (mild TBI; mTBI), presents unique challenges toward protein biomarker discovery and validation given that blood is frequently obtained and processed outside of the clinical laboratory (e.g., athletic fields, battlefield) under variable conditions. As it stands, the field of mTBI blood biomarkers faces a number of outstanding questions. Do elevated blood levels of currently used biomarkers-ubiquitin carboxy-terminal hydrolase L1, glial fibrillary acidic protein, neurofilament light chain, and tau/p-tau-truly mirror the extent of parenchymal damage? Do these different proteins represent distinct injury mechanisms? Is the blood-brain barrier a "brick wall"? What is the relationship between intra- versus extracranial values? Does prolonged elevation of blood levels reflect de novo release or extended protein half-lives? Does biological sex affect the pathobiological responses after mTBI and thus blood levels of protein biomarkers? At the practical level, it is unknown how pre-analytical variables-sample collection, preparation, handling, and stability-affect the quality and reliability of biomarker data. The ever-increasing sensitivity of assay systems and lack of quality control of samples, combined with the almost complete reliance on antibody-based assay platforms, represent important unsolved issues given that false-negative results can lead to false clinical decision making and adverse outcomes. This article serves as a commentary on the state of mTBI biomarkers and the landscape of significant challenges. We highlight and discusses several biological and methodological "known unknowns" and close with some practical recommendations.