Post-Concussion Symptom Scale Score Research Articles

Patient-Specific Alterations in CO2 Cerebrovascular Responsiveness in Acute and Sub-Acute Sports-Related Concussion.

Preliminary studies suggest that sports-related concussion (SRC) is associated with alterations in cerebral blood flow (CBF) regulation. Here, we use advanced magnetic resonance imaging (MRI) techniques to measure CBF and cerebrovascular responsiveness (CVR) in individual SRC patients and healthy control subjects. 15 SRC patients (mean age = 16.3, range 14-20 years) and 27 healthy control subjects (mean age = 17.6, range 13-21 years) underwent anatomical MRI, pseudo-continuous arterial spin labeling (pCASL) MRI and model-based prospective end-tidal targeting (MPET) of CO2 during blood oxygenation level-dependent (BOLD) MRI. Group differences in global mean resting CBF were examined. Voxel-by-voxel group and individual differences in regional CVR were examined using statistical parametric mapping (SPM). Leave-one-out receiver operating characteristic curve analysis was used to evaluate the utility of brain MRI CO2 stress testing biomarkers to correctly discriminate between SRC patients and healthy control subjects. All studies were tolerated with no complications. Traumatic structural findings were identified in one SRC patient. No significant group differences in global mean resting CBF were observed. There were no significant differences in the CO2 stimulus and O2 targeting during BOLD MRI. Significant group and patient-specific differences in CVR were observed with SRC patients demonstrating a predominant pattern of increased CVR. Leave-one-out ROC analysis for voxels demonstrating a significant increase in CVR was found to reliably discriminate between SRC patients and healthy control subjects (AUC of 0.879, p = 0.0001). The optimal cutoff for increased CVR declarative for SRC was 1,899 voxels resulting in a sensitivity of 0.867 and a specificity of 0.778 for this specific ROC analysis. There was no correlation between abnormal voxel counts and Postconcussion Symptom Scale scores among SRC patients. Acute and subacute SRCs are associated with alterations in CVR that can be reliably detected by brain MRI CO2 stress testing in individual patients.

Sport-Related Concussions: Symptom Recurrence After Return to Exercise.

Background:Current guidelines dictate a gradual exercise progression after a concussion; however, it is unclear what proportion of athletes experience a recurrence of symptoms once they are symptom free at rest. Estimating the proportion of athletes and predictors of symptom recurrence would help shape return-to-play protocols.Purpose:To determine the proportion and associated risk factors of athletes who have a recurrence of concussion symptoms with exercise after being symptom free at rest.Study Design:Case-control study; Level of evidence, 3.Methods:Between October 1, 2009 and July 31, 2011, we studied patients from a sport concussion clinic located within a tertiary care regional children’s hospital. Patients were queried at every visit using a standardized questionnaire. Our main outcome variable was recurrence of symptoms with exercise after being symptom free at rest at some point in their recovery. Cofactors included age, sex, loss of consciousness with injury, prior concussion (diagnosed and undiagnosed), Post-Concussion Symptom Scale (PCSS) score, time until clinical presentation, and duration of symptoms.Results:Of the 217 patients included, 25 (12%) experienced a return of symptoms. Losing consciousness at the time of injury and a longer duration between injury and clinical presentation were associated with a decreased risk of symptoms recurring with exercise. Conversely, athletes who had sustained previously undiagnosed concussions and had suffered a longer duration of symptoms at rest were at an increased risk of symptom recurrence with exercise.Conclusion:Relatively few athletes who are symptom free at rest after a concussion will have a recurrence of symptoms when they resume exercise. The risk of symptoms recurring with exercise may be greater among those athletes who sustained previously undiagnosed concussions and had a longer period of symptoms at rest. The early identification of athletes who may be at risk of symptom recurrence will help mold treatment guidelines and exercise progression protocols.

The Effect of Physical Exercise After a Concussion: A Systematic Review and Meta-analysis

Background: Data evaluating the role of exercise in patients with a concussion are contradictory. Studies have reported improvement in the Post-Concussion Symptom Scale (PCSS) score, whereas others showed no effect on the PCSS score. Purpose: To conduct a systematic review and meta-analysis on the role of physical exercise on different outcomes in patients with a concussion. Study Design: Systematic review and meta-analysis. Methods: A search of 5 databases from the earliest available date to September 30, 2016, and a hand search of a few articles were performed. Trial registries were reviewed, and authors of multiple studies were contacted to find additional published or unpublished studies. Randomized controlled trials (RCTs), cohort studies, and before and after (pre-post) studies evaluating the effect of physical exercise, compared with control, in patients with a concussion or mild traumatic brain injury were included. Results: The search generated 1096 studies. Of these, 14 studies (5 RCTs, 1 propensity score matching study, 3 cohort studies, and 5 before and after studies) met our inclusion criteria. Exercise significantly decreased the PCSS score (mean difference, −13.06; 95% CI, −16.57 to −9.55; P < .00001; I2 = 44%), percentage of patients with symptoms of a concussion (risk ratio, 0.74; 95% CI, 0.63 to 0.86; P = .0001; I2 = 0%), and days off work (17.7 days vs 32.2 days, respectively; P < .05) compared with control. Exercise improved the reaction time (standard mean difference, –0.43; 95% CI, −0.80 to −0.06; P = .02) component of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) score without affecting the Balance Error Scoring System (BESS) score and neuropsychological parameters. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) scores were moderate for the PCSS, symptoms, ImPACT, BESS, and neuropsychological tests. Conclusion: Physical exercise appears to improve the PCSS score and symptoms in patients with a concussion. A high-quality RCT evaluating different intensities of exercise at different time points, for different durations after a concussion, for different races/ethnicities, and for sex needs to be conducted to evaluate a clear effect of exercise in patients with a concussion.

Validation of the kinarm end-point robot for clinical assessment of acute sport concussion sensory, motor, and neurocognitive impairment in athletes

ObjectiveTo determine if there is a significant association between KINARM robotic sensorimotor and neurocognitive measurements at baseline, ≤10 days post-concussion (IPC), and when clinically asymptomatic (CA).DesignDouble-blind, prospective case series.SettingFour athletic seasons (2011–2015).Participants1,214 elite athletes (904 males, 310 females, mean age: 18 and 20 years, respectively).Outcome measuresFifty-seven parameters from five robotic tasks (Visually Guided Reaching (VGR), Position Matching (PM), Object Hit, Object Hit and Avoid, Trail Making B (TMB)) characterising sensorimotor and neurocognitive function. Linear regression was used to determine if there was a significant association between baseline, IPC, and CA measurements, adjusting for potential predictors (age, sex, concussion history, recurrent concussion during study, number of baseline assessments, method (seated versus standing), Post-Concussion Symptom Scale Score (PCSS), days post-concussion at testing) and learning effect.Main results95 athletes sustained 102 concussions. There was a clear reduction in performance in concussed athletes on individual parameters compared to non-concussed repeat performance. Significant predictors of impairment were: 1) higher PCSS for VGR (IPC): Reaction Time (p&lt;0.001), Min-Max Speed Difference (m/s) (p=0.001), Path Length Ratio (p=0.001), and TMB (CA): Test Time (p=0.003), Dwell Time (p=0.003); 2) older athletes for VGR (IPC): Speed Maxima Count (p&lt;0.01); 3) less days post-concussion at IPC testing for PM Contraction/Expansion Ratio XY (p=0.005); and 4) recurrent concussion during study period for non-dominant PM Shift Y (p=0.005).ConclusionsResults of this large prospective study suggest the KINARM robot is a valid, objective tool for quantifying sensorimotor and neurocognitive impairment in concussed athletes.Competing interestsBrian W Benson In the future may receive a small royalty from BKIN Technologies Ltd. in consideration for assisting with development and validation of the KINARM end-point robotic device for use in acute sport concussion assessment and management.None.Co-founder and CSO of BKIN Technologies that commercialises the KINARM robot.

Postconcussion Symptoms as a Marker of Delayed Recovery in Children and Youth Who Recently Sustained a Concussion: A Brief Report.

To identify predictors of delayed recovery in children who sustained a concussion and sought care in a pediatric hospital. Retrospective cohort study design. Montreal Children's Hospital Concussion Clinic database. Children who sustained a concussion and sought care within 10 days of the injury, with complete medical history and Postconcussion Symptom Scale (PCSS) score available. Total symptom score on the PCSS, sex, age, history of concussion, sleep disturbances, anxiety, learning disabilities, attention problems, and depression. Delayed recovery (28 days or more). A total of 213 children (F = 76, M = 138) with a mean age of 13.89 ± 2.55 years were included. Only total PCSS score at 10 days postinjury was identified as a significant predictor of delayed recovery (odds ratio: 1.019, P = 0.01). This study demonstrates the potential for clinicians to identify, with the sole use of the PCSS, children at risk of experiencing symptoms for longer periods of time.

Sex Differences in Vestibular/Ocular and Neurocognitive Outcomes After Sport-Related Concussion.

To examine sex differences in vestibular and oculomotor symptoms and impairment in athletes with sport-related concussion (SRC). The secondary purpose was to replicate previously reported sex differences in total concussion symptoms, and performance on neurocognitive and balance testing. Prospective cross-sectional study of consecutively enrolled clinic patients within 21 days of a SRC. Specialty Concussion Clinic. Included male (n = 36) and female (n = 28) athletes ages 9 to 18 years. Vestibular symptoms and impairment was measured with the Vestibular/Ocular Motor Screening (VOMS). Participants completed the Immediate Post-concussion Assessment and Cognitive Test (ImPACT), Post-concussion Symptom Scale (PCSS), and Balance Error Scoring System (BESS). Sex differences on clinical measures. Females had higher PCSS scores (P = 0.01) and greater VOMS vestibular ocular reflex (VOR) score (P = 0.01) compared with males. There were no sex differences on BESS or ImPACT. Total PCSS scores together with female sex accounted for 45% of the variance in VOR scores. Findings suggest higher VOR scores after SRC in female compared with male athletes. Findings did not extend to other components of the VOMS tool suggesting that sex differences may be specific to certain types of vestibular impairment after SRC. Additional research on the clinical significance of the current findings is needed.

Are UCH-L1 and GFAP promising biomarkers for children with mild traumatic brain injury?

Objectives: To compare serum biomarker levels between children with mild traumatic brain injury (mTBI) and orthopaedic injury (OI), acutely following injury. Secondarily, to explore the association between biomarker levels and symptom burden over 1 month post-injury.Methods: This was a prospective cohort study of children aged 11–16 years who presented to the emergency department within 6 hours of sustaining mTBI or isolated extremity OI. Serum was drawn at the time of study enrollment and levels of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) and glial fibrillary acid protein (GFAP) were analysed. Symptom burden was assessed by the Post-Concussion Symptom Scale (PCSS) acutely following injury and at three subsequent time points over 1 month.Results: Twenty-five children with mTBI and 20 children with OI were enrolled. The average age for the overall cohort was 13 (± 1.6) years and the majority were male and injured playing sports. GFAP levels and PCSS scores were significantly higher acutely following mTBI vs OI (p < 0.01). There was not a significant group difference in UCH-L1 levels. Neither GFAP nor UCH-L1 were predictive of PCSS scores over the 1month post-injury.Conclusions: GFAP may be a promising diagnostic tool for children with mTBI. Additional approaches are needed to predict symptom severity and persistence.

The Effect of Over-the-Counter Medication on Symptom Severity Following Sport-Related Concussion

PURPOSE: Although over-the-counter (OTC) medications are commonly administered following sport-related concussion, their effect on reducing symptoms remains unknown. We sought to examine the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) and melatonin on post-concussion symptom severity. METHODS: We conducted a prospective cohort study of patients who presented to a sport concussion clinic within 21 days of injury. We examined the effect of NSAID use on the sum of “Headache” and “Pressure in the Head” scores (HA score) on the post-concussion symptom scale (PCSS) endorsed by the international consensus on concussion in sport. In addition, we examined the effect of melatonin on “Trouble Falling Asleep” scores (Sleep score). Patients who reported taking NSAIDs (n=30) and melatonin (n=16) were matched by age, gender, HA or Sleep score respectively, and overall PCSS scores with controls (n=70 and 35 respectively) who did not report the use of these medications. Mean differences in PCSS scores from the initial clinic visit and first follow-up visit were compared by repeated measures ANOVA. RESULTS: There was significant improvement in mean HA score for both NSAID users (6.4 vs. 3.7; p<0.001) and non-users (6.6 vs.2.8; p<0.001). The mean difference in HA score between initial visit and follow-up visit of NSAID users was not significantly different than that of non-users (2.7 vs. 3.8; p=0.102). Similarly, there was significant improvement in Sleep score between visits in both melatonin users (3.8 vs. 2.0; p<0.001) and non-users (3.7 vs. 1.6; p<0.001) showed. The mean difference in Sleep score between initial visit and follow-up visit, however, did not differ between those who used melatonin and those who didn’t (1.8 vs. 2.1; p=0.691). CONCLUSION: Headache symptom severity and difficulty falling asleep are commonly treated following concussion using OTC medications such as NSAIDs and melatonin. Our results suggest that symptom severity improves over time, but this effect may not be enhanced by the use of OTC medications.

Role of Pre-Morbid Factors and Exposure to Blast Mild Traumatic Brain Injury on Post-Traumatic Stress in United States Military Personnel.

Mild traumatic brain injury (mTBI), the signature injury of the recent wars in Afghanistan and Iraq, is a prevalent and potentially debilitating condition that is associated with symptoms of post-traumatic stress/post-traumatic stress disorder (PTS/PTSD). Prior mTBI, severity and type of injury (blast vs. non-blast), and baseline psychiatric illness are thought to impact mTBI outcomes. It is unclear if the severity of pre-morbid PTS/PTSD is a risk factor of post-injury levels of PTS and mTBI symptoms. The objective of the study was to examine predictors of post-injury PTS/PTSD, including pre-morbid PTS symptoms, and physical and cognitive symptoms in the sub-acute phase (1 week-3 months) following an acute mTBI. A retrospective review of medical records was performed of 276 servicemen assigned to the United States Army Special Operations Command referred for mTBI evaluation between December 2009 and March 2011. Post-Concussion Symptom Scale and PTSD Checklist scores were captured pre- and post-injury. A total of 276 records were reviewed. Pre-morbid and post-injury data were available for 91% (251/276). Of the 54% (136/251) of personnel with mTBI, 29% (39/136) had positive radiology findings and 11% (15/136) met criteria for clinical PTS symptoms at baseline. Logistic regression analysis found baseline PTS symptoms predicted personnel who met clinical levels of PTSD. Receiver operating characteristic curve analysis revealed that baseline PTS (p = 0.001), baseline mTBI symptoms (p = 0.001), and positive radiology (magnetic resonance imaging or computed tomography) findings for complicated mTBI (p = 0.02) accurately identified personnel with clinical levels of PTSD following mTBI. Years of military service, combat deployment status, age, and injury mechanism (blast vs. non-blast) were not associated with increased risk of PTS following mTBI. Pre-morbid PTS symptoms are associated with an increased risk for clinical levels of PTS following a subsequent mTBI. Symptom severity and positive radiologic findings may amplify this risk. At-risk personnel may benefit from early identification and intervention.

Physical Activity Level and Symptom Duration Are Not Associated After Concussion

Background: Physical rest after a concussion has been described as a key component in the management of the injury. Evidence supporting this recommendation, however, is limited. Purpose: To examine the association between physical activity and symptom duration in a cohort of patients after a concussion. Study Design: Cohort study; Level of evidence, 2. Methods: This study included 364 patients who were diagnosed with a concussion, were seen by a physician within 3 weeks of injury, and completed a questionnaire at the initial clinic visit. The questionnaire assessed the postconcussion symptom scale (PCSS) score, previous number of concussions, presence of the loss of consciousness or amnesia at the time of injury, and prior treatment for headaches. During each follow-up clinic visit, physical activity level was self-reported. A Cox proportional hazard model was constructed to determine the association between symptom duration, initial clinic visit responses, and self-reported physical activity level after the injury. Results: Study participants ranged in age from 8 to 27 years (mean age, 15.0 years) and had sustained a mean of 0.8 prior concussions; 222 patients (61%) were male. On initial examination, the mean PCSS score was 34.7. The mean symptom duration was 48.9 days after the injury. Among the variables included in the model, initial PCSS score and female sex were independently associated with symptom duration, while physical activity level after the injury was not. For participants aged between 13 and 18 years, however, higher levels of physical activity after the injury were associated with a shorter symptom duration. Conclusion: Results from this study indicate that physical activity after the injury may not be universally detrimental to the recovery of concussion symptoms.

Initial symptom burden predicts duration of symptoms after concussion.

To determine which variables predict prolonged (>28 days) duration of symptoms after a concussion. We conducted a prospective cohort study of adult (>18yo) patients cared for in a specialty concussion clinic. Symptoms were assessed using the Post-Concussion Symptom Scale (PCSS) developed at the 3rd International Conference on Concussion in Sports. Possible predictors including age, sex, loss of consciousness, amnesia, history of prior concussion, prior treatment for headaches, history of migraines, and family history of concussions, were measured by self-report. We recorded a PCSS score at each clinical visit and defined time to symptom resolution as the number of days between the date of injury and date of last symptoms. Of 64 adult patients included in the study, 53.3% were male; 20.3% reported experiencing a loss of consciousness at the time of injury while 23.4% reported amnesia. Patients ranged in age from 18 to 27 years (mean 21±2 years). Most concussions (92.2%) occurred during sports. The mean initial PCSS score for those suffering symptoms for longer than 28 days was significantly higher than those who symptoms resolved within 28 days (42.5 vs. 19.2, p<0.01). Of all potential predictor variables, only the initial PCSS score was independently associated with the odds of symptoms lasting longer than 28 days (aOR 1.037; 95% CI 1.011, 1.063). Among adult patients with concussions, those with a higher symptom burden after injury have an increased odds of suffering from prolonged symptoms. Other potential predictor variables are not associated with the risk of prolonged recovery.

Can Computerized Neuropsychological Testing in the Emergency Department Predict Recovery for Young Athletes With Concussions?

The objective of this study was to determine if computerized neurocognitive testing (Immediate Post-Concussion Assessment and Cognitive Testing [ImPACT]) in the emergency department (ED) can be used as a prognostic tool to detect young athletes at risk of having protracted concussive symptoms. This was a prospective cohort study of athletes aged 11 to 18 years who presented to an ED less than 24 hours after sustaining a sports-related concussion. ImPACT was administered in the ED, and performance was categorized as "poor" if the athlete had 3 (of 4) or greater low domain scores. Participants completed the Post-Concussion Symptom Scale (PCSS) in the ED and by phone at 1 and 2 weeks after injury. Athletes were symptomatic if their PCSS score was more than 6 in males and more than 8 in females. One hundred nine patients were enrolled; 60% and 36% remained symptomatic at 1 and 2 weeks after injury, respectively. "Poor" ImPACT performance was not particularly useful in predicting athletes with protracted symptoms (at 1 week: positive predictive value, 70.8%; negative predictive value, 43.5%; at 2 weeks: positive predictive value, 47.8%; negative predictive value, 68.9%). In bivariate analysis, a higher ED PCSS score was associated with protracted symptoms (at 1 week: odds ratio, 1.1 [confidence interval, 1.0-1.1]; at 2 weeks: odds ratio, 1.0 [confidence interval, 1.0-1.1]). Computerized neurocognitive testing in the ED has limited usefulness in predicting protracted symptoms. Total acute symptom burden may be a useful prognostic tool in the ED evaluation of concussed young athletes, yet further research is necessary.

Psychiatric outcomes after pediatric sports-related concussion.

The objectives of this study were twofold: (1) to examine the prevalence of emotional symptoms among children and adolescents with a sports-related concussion (SRC) who were referred to a multidisciplinary pediatric concussion program and (2) to examine the prevalence, clinical features, risk factors, and management of postinjury psychiatric outcomes among those in this clinical population. The authors conducted a retrospective chart review of all patients with SRC referred to a multidisciplinary pediatric concussion program between September 2013 and October 2014. Clinical assessments carried out by a single neurosurgeon included clinical history, physical examination, and Post-Concussion Symptom Scale (PCSS) scoring. Postinjury psychiatric outcomes were defined as a subjective worsening of symptoms of a preinjury psychiatric disorder or new and isolated suicidal ideation or diagnosis of a novel psychiatric disorder (NPD). An NPD was defined as a newly diagnosed psychiatric disorder that occurred in a patient with or without a lifetime preinjury psychiatric disorder after a concussion. Clinical resources, therapeutic interventions, and clinical and return-to-play outcomes are summarized. One hundred seventy-four patients (mean age 14.2 years, 61.5% male) were included in the study. At least 1 emotional symptom was reported in 49.4% of the patients, and the median emotional PCSS subscore was 4 (interquartile range 1-8) among those who reported at least 1 emotional symptom. Overall, 20 (11.5%) of the patients met the study criteria for a postinjury psychiatric outcome, including 14 patients with an NPD, 2 patients with isolated suicidal ideation, and 4 patients with worsening symptoms of a preinjury psychiatric disorder. Female sex, a higher initial PCSS score, a higher emotional PCSS subscore, presence of a preinjury psychiatric history, and presence of a family history of psychiatric illness were significantly associated with postinjury psychiatric outcomes. Interventions for patients with postinjury psychiatric outcomes included pharmacological therapy alone in 2 patients (10%), cognitive behavioral therapy alone in 4 (20%), multimodal therapy in 9 (45%), and no treatment in 5 (25%). Overall, 5 (25%) of the patients with postinjury psychiatric disorders were medically cleared to return to full sports participation, whereas 5 (25%) were lost to follow-up and 9 (45%) remained in treatment by the multidisciplinary concussion program at the end of the study period. One patient who was asymptomatic at the time of initial consultation committed suicide. Emotional symptoms were commonly reported among pediatric patients with SRC referred to a multidisciplinary pediatric concussion program. In some cases, these symptoms contributed to the development of an NPD, isolated suicidal ideation, and worsening symptoms of a preexisting psychiatric disorder. Future research is needed to clarify the prevalence, pathophysiology, risk factors, and evidence-based management of postinjury psychiatric outcomes after pediatric SRC. Successful management of these patients requires prompt recognition and multidisciplinary care by experts with clinical training and experience in concussion and psychiatry.

The Effect of Preinjury Sleep Difficulties on Neurocognitive Impairment and Symptoms After Sport-Related Concussion

Background: Researchers have reported that sleep duration is positively related to baseline neurocognitive performance. However, researchers have yet to examine the effect of preinjury sleep difficulties on postconcussion impairments. Purpose: To compare neurocognitive impairment and symptoms of athletes with preinjury sleep difficulties to those without after a sport-related concussion (SRC). Study Design: Cohort study; Level of evidence, 3. Methods: The sample included 348 adolescent and adult athletes (age, mean ± SD, 17.43 ± 2.34 years) with a diagnosed SRC. The sample was divided into 2 groups: (1) 34 (10%) participants with preinjury sleep difficulties (sleeping less as well as having trouble falling asleep; SLEEP SX) and (2) 231 (66%) participants without preinjury sleep difficulties (CONTROL). The remaining 84 (24%) participants with minimal sleep difficulties (1 symptom) were excluded. Participants completed the Immediate Postconcussion Assessment and Cognitive Test (ImPACT) and Postconcussion Symptom Scale (PCSS) at baseline and 3 postinjury intervals (2, 5-7, and 10-14 days after injury). A series of repeated-measures analyses of covariance with Bonferroni correction, controlling for baseline non–sleep-related symptoms, were conducted to compare postinjury neurocognitive performance between groups. Follow-up exploratory t tests examined between-group differences at each time interval. A series of analyses of variance were used to examine total PCSS score, sleep-related, and non–sleep-related symptoms across time intervals between groups. Results: Groups differed significantly in PCSS scores across postinjury intervals for reaction time (P < .001), with the preinjury SLEEP SX group performing worse than controls at 5-7 days (mean ± SD, 0.70 ± 0.32 [SLEEP SX], 0.60 ± 0.14 [CONTROL]) and 10-14 days (0.61 ± 0.17 [SLEEP SX]; 0.57 ± 0.10 [CONTROL]) after injury. Groups also differed significantly on verbal memory performance (P = .04), with the SLEEP SX (68.21 ± 18.64) group performing worse than the CONTROL group (76.76 ± 14.50) 2 days after injury. The SLEEP SX group reported higher total symptom (P = .02) and sleep-related symptom (P = .02) scores across postinjury time intervals. Conclusion: Preinjury sleep difficulties may exacerbate neurocognitive impairment and symptoms after concussion. The findings may help clinicians identify athletes who are at risk for worse impairments after a concussion due to preinjury sleep difficulties.

Sleep Disturbance and Neurocognitive Function During the Recovery From a Sport-Related Concussion in Adolescents

Background: Sleep disturbances are a hallmark sign after a sport-related concussion (SRC). Poor sleep has been shown to adversely affect baseline neurocognitive test scores, but it is not comprehensively understood how neurocognitive function is affected by disrupted sleep during recovery from a concussion. Purpose: To identify the correlation between adolescent athletes’ neurocognitive function and their self-reported sleep quantity and sleep disturbance symptoms during recovery from SRC. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Immediate Post-Concussion Assessment and Cognition Testing (ImPACT) data were retrospectively collected for 545 adolescent athletes treated for SRC at a sports medicine concussion clinic. Patients were stratified into groups based on 2 criteria: self-reported sleep duration and self-reported sleep disturbance symptoms during postinjury ImPACT testing. Sleep duration was classified as short (<7 hours), intermediate (7-9 hours), and long (>9 hours). Sleep disturbance symptoms were self-reported as part of the Post-Concussion Symptom Scale (PCSS) as either sleeping less than normal, sleeping more than normal, or having trouble falling asleep. One-way analyses of variance were conducted to examine the effects that sleep duration as well as self-reported sleep disturbance symptoms had on composite scores. A total of 1067 ImPACT tests were analyzed: test 1, 545; test 2, 380; and test 3, 142. Results: Sleeping fewer than 7 hours the night before testing correlated with higher PCSS scores (P < .001), whereas sleeping longer than 9 hours correlated with worse visual memory (P = .01), visual motor speed (P <.001), and reaction time (P = .04) composite scores. With regard to self-reported sleep disturbance symptoms, patients demonstrated worse composite scores during ImPACT testing when they self-reported sleeping more than normal (ImPACT test 1: verbal memory, P < .001; visual motor speed, P = .05; reaction time, P = .01; ImPACT test 2: verbal memory, P < .001; visual memory, P < .001; visual motor speed, P < .001; reaction time, P = .01). Adolescent patients recovering from SRC demonstrated higher (worse) PCSS scores (P < .001) when they sensed that their sleep had been disrupted. Conclusion: Adolescent patients who perceive that their sleep is somehow disrupted after SRC may report a greater number of concussion symptoms during their recovery. In addition, the study results suggest that sleeping more than normal may identify an individual who continues to be actively recovering from concussion, given the correlation between lower neurocognitive function and this self-reported symptom.

Early symptom burden predicts recovery after sport-related concussion.

To identify independent predictors of and use recursive partitioning to develop a multivariate regression tree predicting symptom duration greater than 28 days after a sport-related concussion. We conducted a prospective cohort study of patients in a sports concussion clinic. Participants completed questionnaires that included the Post-Concussion Symptom Scale (PCSS). Participants were asked to record the date on which they last experienced symptoms. Potential predictor variables included age, sex, score on symptom inventories, history of prior concussions, performance on computerized neurocognitive assessments, loss of consciousness and amnesia at the time of injury, history of prior medical treatment for headaches, history of migraines, and family history of concussion. We used recursive partitioning analysis to develop a multivariate prediction model for identifying athletes at risk for a prolonged recovery from concussion. A total of 531 patients ranged in age from 7 to 26 years (mean 14.6 ± 2.9 years). The mean PCSS score at the initial visit was 26 ± 26; mean time to presentation was 12 ± 5 days. Only total score on symptom inventory was independently associated with symptoms lasting longer than 28 days (adjusted odds ratio 1.044; 95% confidence interval [CI] 1.034, 1.054 for PCSS). No other potential predictor variables were independently associated with symptom duration or useful in developing the optimal regression decision tree. Most participants (86%; 95% CI 80%, 90%) with an initial PCSS score of <13 had resolution of their symptoms within 28 days of injury. The only independent predictor of prolonged symptoms after sport-related concussion is overall symptom burden.

Structural connectivity abnormality in children with acute mild traumatic brain injury using graph theoretical analysis.

The traumatic biomechanical forces associated with mild traumatic brain injury (mTBI) typically impart diffuse, as opposed to focal, brain injury potentially disrupting the structural connectivity between neural networks. Graph theoretical analysis using diffusion tensor imaging was used to assess injury-related differences in structural connectivity between 23 children (age 11-16 years) with mTBI and 20 age-matched children with isolated orthopedic injuries (OI) scanned within 96 h postinjury. The distribution of hub regions and the associations between alterations in regional network measures and symptom burden, as assessed by the postconcussion symptom scale score (PCSS), were also examined. In comparison to the OI group, the mTBI group was found to have significantly higher small-worldness (P < 0.0001), higher normalized clustering coefficients (P < 0.0001), higher normalized characteristic path length (P = 0.007), higher modularity (P = 0.0005), and lower global efficiency (P < 0.0001). A series of hub regions in the mTBI group were found to have significant alterations in regional network measures including nodal degree, nodal clustering coefficient, and nodal between-ness centrality. Correlation analysis showed that PCSS total score acquired at the time of imaging was significantly associated with the nodal degree of two hubs, the superior frontal gyrus at orbital section and the middle frontal gyrus. These findings provide new evidence of acute white matter alteration at both global and regional network level following mTBI in children furthering our understanding of underlying mechanisms of acute neurological insult associated with mTBI.

Effect of Cognitive Activity Level on Duration of Post-Concussion Symptoms

To determine the effect of cognitive activity level on duration of post-concussion symptoms. We conducted a prospective cohort study of patients who presented to a Sports Concussion Clinic within 3 weeks of injury between October 2009 and July 2011. At each visit, patients completed a scale that recorded their average level of cognitive activity since the previous visit. The product of cognitive activity level and days between visits (cognitive activity-days) was calculated and divided into quartiles. Kaplan-Meier Product Limit method was used to generate curves of symptom duration based on cognitive activity level. To adjust for other possible predictors of concussion recovery, we constructed a Cox proportional hazard model with cognitive activity-days as the main predictor. Of the 335 patients included in the study, 62% were male, 19% reported a loss of consciousness, and 37% reported experiencing amnesia at the time of injury. The mean age of participants was 15 years (range, 8-23) and the mean number of previous concussions was 0.76; 39% of athletes had sustained a previous concussion. The mean Post-Concussion Symptom Scale score at the initial visit was 30 (SD, 26). The overall mean duration of symptoms was 43 days (SD, 53). Of all variables assessed, only total symptom burden at initial visit and cognitive activity level were independently associated with duration of symptoms. Increased cognitive activity is associated with longer recovery from concussion. This study supports the use of cognitive rest and adds to the current consensus opinion.

The Prevalence of Undiagnosed Concussions in Athletes

Previous studies suggest athletes underreport concussions. We sought to determine whether athletes in our clinics have sustained previous concussions that went undiagnosed. Multicentered cross sectional study. Two sport concussion clinics. Patients diagnosed with sport-related concussions or concussions with injury mechanisms and forces similar to those observed in sports were included. The proportion of patients who answered "yes" to the following question were defined as having a previously undiagnosed concussion: "Have you ever sustained a blow to the head which was NOT diagnosed as a concussion but was followed by one or more of the signs and symptoms listed in the Post Concussion Symptom Scale?" Of the 486 patients included in the final analysis, 148 (30.5%) patients reported a previously undiagnosed concussion. Athletes reporting previously undiagnosed concussions had a higher mean Post Concussion Symptom Scale (PCSS) score (33 vs 25; P < 0.004) and were more likely to have lost consciousness (31% vs 22%; P = 0.038) with their current injury than athletes without previously undiagnosed concussions. Nearly one-third of athletes have sustained previously undiagnosed concussions, defined as a blow to the head followed by the signs and symptoms included in the PCSS. Furthermore, these previously undiagnosed concussions are associated with higher PCSS scores and higher loss of consciousness rates when future concussions occur. Many athletes have sustained previous blows to the head that result in the signs and symptoms of concussion but have not been diagnosed with a concussion. These injuries are associated with increased rates of loss of consciousness and higher symptom scale scores with future concussions.

Symptom Severity Predicts Prolonged Recovery after Sport-Related Concussion, but Age and Amnesia Do Not

To identify predictors of prolonged symptoms in athletes who sustain concussions. This was a multicenter prospective cohort study of patients in 2 sport concussion clinics. Possible predictors of prolonged symptoms from concussion were compared in 2 groups, those whose symptoms resolved within 28 days and those whose symptoms persisted beyond 28 days. Candidate predictor variables were entered into a logistic regression model that was used to generate aORs. A total of 182 patients met the inclusion criteria during the study period. The mean patient age was 15.2 ± 3.04 years. More than one-third of the patients (n = 65) underwent computerized neurocognitive testing on their initial visit. On univariate analyses, Post-Concussion Symptom Scale (PCSS) score and all composite scores on computerized neurocognitive testing were apparently associated with prolonged symptom duration. Sex, age, loss of consciousness at time of injury, and amnesia at time of injury were not associated with prolonged symptom duration. After adjusting for potential confounding, only total PCSS score was associated with the odds of suffering prolonged symptoms. Further efforts to develop clinical tools for predicting which athletes will suffer prolonged recoveries after concussion should focus on initial symptom score.