Amy J. Jak

Objective:The vast majority of existing research on outcomes following concussion is androcentric with women notably understudied in all settings where concussion commonly occurs, including sport, military, and civilian domains. Clinical care for concussed women is, by extension, far less evidenced-based as it is largely extrapolated from male-dominated studies. We therefore sought to center concussion outcomes of women in big data sources in this investigation to capitalize on both sample size and breadth of setting in which concussion occurs.Participants and Methods:We identified all studies with publicly released data as of 4/7/21 that included both male and female adults, enough information to determine severity of injury consistent with concussion/mild traumatic brain injury (TBI), a measure of postconcussive symptoms (PCS), and objective measures of neurocognitive functioning from the Federal Interagency Traumatic Brain Injury Research (FITBIR) Informatics System. FITBIR is a collaborative effort of the National Institutes of Health (NIH) and the Department of Defense (DoD), developed to share data across the entire TBI research community. This resulted in inclusion of six studies with a total of 9370 participants, 32% female. PCS data was drawn from the Neurobehavioral Symptom Inventory (NSI), the Rivermead Post-Concussion Symptoms Questionnaire (RPSQ), and the Sport Concussion Assessment Tool - 3rd Edition (SCAT 3), specifically the 22-item participant symptom evaluation rated on a 7-point scale. The questionnaires were harmonized and the following symptom domains emerged: Somatic, Cognitive, and Affective. Data were analyzed using linear mixed-effects models.Results:We found a small to medium sized significant effect of sex, with women reporting higher symptoms overall. Mean symptom endorsement scores were higher overall on the NSI in comparison to the RPSQ and SCAT (ps < .001). Follow-up analyses revealed sex differences were largest for cognitive symptoms, followed by somatic symptoms, then affective symptoms. We also found significant main effects of population (military>sport/civilian, p = .003) and sex (women>males, p < .001) on the overall composite, as well as a significant population-by-sex interaction such that female service members/veterans endorsed the highest rates of symptoms (p < .001). Similar patterns of significance and effect sizes were observed for the somatic and affective composites. Cognitive symptom composites showed a similar pattern, but with smaller effect sizes overall. Racial and ethnic diversity was also limited in the sample.Conclusions:In one of the largest samples of women to date, we found a small to medium effect of sex on symptom reporting such that women reported higher levels of postconcussive symptoms than males. Notably, however, the women in military/Veteran samples endorsed the highest levels of symptoms. Despite using a large publicly available dataset to maximize the representation of women, the current sample was still predominantly male and racial and ethnic diversity among the sample was not consistent with expected broader population demographics. Dramatically more concerted efforts need to be made to engage women in all spheres of concussion research (military, civilian, and sport). Strategies to be more inclusive in concussion research will be highlighted.

The purpose of this study was 2-fold: (a) to evaluate whether perception of work ability is associated with employment status in a sample of combat-exposed veterans, and (b) to determine whether the same sets of variables that are associated with employment status are also associated with perception of work ability. Research Method/Design: In this cross-sectional study, veterans (N = 83) underwent a neuropsychological assessment and completed questionnaires assessing demographic characteristics, combat-related experiences, and psychiatric and neurobehavioral/health-related symptoms. Primary outcomes of interest were employment status (unemployed vs. employed) and veterans' perception of whether their ability to work has declined due to an ongoing condition (yes vs. no). A chi-square analysis revealed a significant relationship between perception of work ability and employment status. Additionally, psychiatric and neurobehavioral/health-related symptoms were associated with employment status and perception of work ability, whereas demographic characteristics (i.e., service-connected disability rating) and combat-related experiences (i.e., mTBI history) were only associated with perception of work ability. Objective cognitive functioning was not associated with employment status or perception of work ability. Although preliminary, results suggest that perception of work ability is an important factor to consider when evaluating employment-related outcomes in veterans. Moreover, results indicate that while there is some overlap among the variables associated with employment status and perception of work ability, additional variables are linked with perception of work ability. Taken together, these findings suggest that perception of one's ability to work and factors that influence it may be particularly important treatment targets in the veteran population. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Objective: To investigate the biological, cognitive, and psychological presentations of combat-exposed Veterans with a history of mild traumatic brain injury (mTBI) and/or posttraumatic stress disorder (PTSD) using a novel white matter imaging technique and comprehensive neuropsychological assessment. Method: 74 Iraq and Afghanistan Veterans (mean age 33.89, 90.5% male) with history of mTBI (average 7.25 years since injury), PTSD, both, or neither underwent magnetic resonance imaging (MRI) exams including acquisition of a novel imaging technique, multicomponent-driven equilibrium single-pulse observation of T1/T2 (mcDESPOT) to quantify myelin water fraction (MWF), a surrogate measure of myelin content. Participants also underwent comprehensive neuropsychological assessment and three cognitive composite scores (memory, working memory/processing speed, and executive functioning) were created. Results: There were no significant group differences on the neuropsychological composite scores. ANCOVAs revealed a main effect of PTSD across all a priori regions of interest (ROI) in which PTSD was associated with higher MWF. There was no main effect of mTBI history or TBI by PTSD interaction on any ROI. Significant positive associations were observed between myelin and PTSD symptoms, but no significant associations were found between myelin and neurobehavioral symptoms. No significant associations were found between myelin in the a priori ROIs and the cognitive composite scores. Conclusion: This study did not find neuropsychological or MWF differences in combat Veterans with a remote history of mTBI but did find myelin alterations related to PTSD. Psychological trauma should be a primary target for intervention in Veterans with comorbid PTSD and mTBI reporting subjective complaints, given its salience.

Objective: The D-KEFS Color Word Interference Test (CWIT) is among the most commonly administered measures of verbally mediated processing speed and executive functioning. Previous research suggests that this test may also be sensitive to performance invalidity. We sought to develop new embedded measures of performance invalidity based on multi-condition performance on the CWIT and to evaluate previously proposed embedded measures for performance invalidity on this test. Method: Newly developed and previously proposed embedded measures were evaluated in three samples: a traumatic brain injury (TBI) sample (N = 224) classified into psychometrically-defined performance-valid and performance-invalid subgroups; the D-KEFS normative sample (N = 1,735); and a Parkinson’s disease sample (N = 166). To explore the resilience of CWIT cutoffs to the effects of age and neurocognitive impairment, the D-KEFS normative sample was stratified into age groups of 8–19, 20–69, and 70–89 and the Parkinson’s disease sample into normal cognition, mild cognitive impairment, and dementia groups. Results: Our newly developed embedded measures derived from within the TBI sample were largely resilient to the effects of age and neurocognitive impairment other than dementia. Overall, a cutoff of ≤18 on the sum of age-corrected scaled scores on all four conditions exhibited the strongest classification accuracy. In contrast, previously proposed cutoffs (Erdodi et al., 2018 Erdodi, L. A. , Sagar, S. , Seke, K. , Zuccato, B. G. , Schwartz, E. S. , & Roth, R. M. (2018). The Stroop test as a measure of performance validity in adults clinically referred for neuropsychological assessment. Psychological Assessment, 30(6), 755–766. doi: 10.1037/pas0000525 [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] ) produced unacceptable false-positive rates within the TBI sample and generally a high rate of potential false positives in the normative age and clinical groups. Conclusion: Scoring ≤18 on the sum of all conditions on the CWIT appears to be an optimal cutoff for performance invalidity detection in non-demented samples.

Introduction: Mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) are highly prevalent comorbid conditions in military Veterans. However, lack of appropriate comparison groups has clouded interpretation of the chronic effects of these conditions. The present study evaluated the neuropsychological, psychiatric/neurobehavioral, and functional outcomes associated with mTBI and PTSD in a well-characterized sample of combat-exposed Veterans. Method: Participants included 73 Iraq/Afghanistan Veterans (91.8% male; age: M = 34.00, SD = 6.39) divided into four groups: mTBI-only (n = 23), PTSD-only (n = 14), comorbid mTBI + PTSD (n = 19), and combat-control (CC; n = 17). Participants were administered a neuropsychological assessment and completed questionnaires assessing psychiatric/neurobehavioral symptoms and functional outcomes. Results: Kruskal-Wallis H-tests showed no group differences across measures of neuropsychological functioning; however, there were significant differences across groups on all psychiatric/neurobehavioral variables examined. In general, the comorbid and PTSD-only groups endorsed the most severe symptoms, followed by the mTBI-only and CC groups, respectively. As for functional outcomes, the comorbid and PTSD-only groups had higher rates of service-connection disability and greater perceived decline in work and education-related abilities, relative to the mTBI-only and CC groups, despite similar proportions of Veterans employed or in school in each group. Conclusions: Findings suggest that Veterans with comorbid mTBI + PTSD and PTSD alone are at greatest risk for experiencing long-lasting subjective distress, including negative perceptions of their ability to work or pursue an education, despite being comparable to mTBI-only and CC Veterans on objective measures of functioning. Our results highlight the importance of emphasizing mental health treatment in this population.

Objective To better concurrently address emotional and neuropsychological symptoms common in veterans with comorbid post-traumatic stress disorder (PTSD) and history of traumatic brain injury (TBI), we integrated components of compensatory cognitive training from the Cognitive Symptom Management and Rehabilitation Therapy (CogSMART) programme into cognitive processing therapy (CPT) for PTSD to create a hybrid treatment, SMART-CPT (CogSMART+CPT). This study compared the efficacy of standard CPT with SMART-CPT for treatment of veterans with comorbid PTSD and history of TBI reporting cognitive symptoms. Methods One hundred veterans with PTSD, a history of mild to moderate TBI and current cognitive complaints were randomised and received individually delivered CPT or SMART-CPT for 12 weeks. Participants underwent psychological, neurobehavioural and neuropsychological assessments at baseline, on completion of treatment and 3 months after treatment. Results Both CPT and SMART-CPT resulted in clinically significant reductions in PTSD and postconcussive symptomatology and improvements in quality of life. SMART-CPT resulted in additional improvements in the neuropsychological domains of attention/working memory, verbal learning/memory and novel problem solving. Conclusion SMART-CPT, a mental health intervention for PTSD, combined with compensatory cognitive training strategies, reduces PTSD and neurobehavioural symptoms and also provides added value by improving cognitive functioning.

Objective: The purpose of this review was to examine sex differences in concussion, or mild traumatic brain injury (mTBI) outcome, updating previous critical reviews of the literature. Method: Within adult human studies, we reviewed a wide range of concussion outcome variables: prevalence of concussion, injury characteristics, postconcussion symptom trajectories and psychiatric distress, neuropsychological performance, and neuroimaging findings. Sports-related concussion, civilian, and military samples were included in the review. Results: Given the robust concussion literature, there is a relative paucity of research addressing sex differences following concussion. The majority of available studies focused on sports-related concussion, with fewer studies targeting other civilian causes of concussion or military-related concussion in females. Prevalence of concussion was generally reported to be higher in females than males. Although symptom reporting largely showed a pattern for females to report greater overall symptoms than males, examining individual symptoms or symptom clusters resulted in mixed findings between the sexes. Neuropsychological studies generally showed females performing more poorly than males on measures of visual memory following concussion, though this finding was not consistently reported. Conclusion: Research examining sex differences in humans following concussion, in general, is in its infancy, and exploration of sex differences in studies outside of the sports concussion domain is particularly nascent. Given the increased prevalence of concussion and potential higher symptom reporting among women, ongoing research is necessary to better understand the role of biological sex on outcome following concussion. Understanding sex differences has important implications for assessment, management, and treatment of concussion.

Objective: Posttraumatic stress disorder (PTSD), history of mild traumatic brain injury (mTBI), and executive function (EF) difficulties are prevalent in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Veterans. We evaluated the contributions of injury variables, lower-order cognitive component processes (processing speed/attention), and psychological symptoms to EF.Participants: OEF/OIF Veterans (N= 65) with PTSD and history of mTBI were administered neuropsychological tests of EF and self-report assessments of PTSD and depression.Results: Those impaired on one or more EF measures had higher PTSD and depression symptoms and lower processing speed/attention performance than those with intact performance on all EF measures. Across participants, poorer attention/processing speed performance and higher psychological symptoms were associated with worse performance on specific aspects of EF (eg, inhibition and switching) even after accounting for injury variables. Although direct relationships between EF and injury variables were equivocal, there was an interaction between measures of injury burden and processing speed/attention such that those with greater injury burden exhibited significant and positive relationships between processing speed/attention and inhibition/switching, whereas those with lower injury burden did not.Conclusion: Psychological symptoms as well as lower-order component processes of EF (attention and processing speed) contribute significantly to executive dysfunction in OEF/OIF Veterans with PTSD and history of mTBI. However, there may be equivocal relationships between injury variables and EF that warrant further study. Results provide groundwork for more fully understanding cognitive symptoms in OEF/OIF Veterans with PTSD and history of mTBI that can inform psychological and cognitive interventions in this population.