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AbstractObjective: The present study aimed to examine the impact of lifetime blast exposure (LBE) on neuropsychological functioning in service members and veterans (SMVs). Method: Participants were 282 SMVs, with and without history of traumatic brain injury (TBI), who were prospectively enrolled in a Defense and Veterans Brain Injury Center (DVBIC)-Traumatic Brain Injury Center of Excellence (TBICoE) Longitudinal TBI Study. A cross-sectional analysis of baseline data was conducted. LBE was based on two factors: Military Occupational Speciality (MOS) and SMV self-report. Participants were divided into three groups based on LBE: Blast Naive (n = 61), Blast + Low Risk MOS (n = 96), Blast + High Risk MOS (n = 125). Multivariate analysis of variance (MANOVA) was used to examine group differences on neurocognitive domains and the Minnesota Multiphasic Personality Inventory-2 Restructured Form. Results: There were no statistically significant differences in attention/working memory, processing speed, executive functioning, and memory (Fs < 1.75, ps > .1, ηp2s < .032) or in General Cognition (Fs < 0.95, ps > .3, ηp2s < .008). Prior to correction for covariates, lifetime blast exposure was related to Restructured Clinical (F(18,542) = 1.77, p = .026, ηp2 = .055), Somatic/Cognitive (F(10,550) = 1.99, p = .033, ηp2 = .035), and Externalizing Scales (F(8,552) = 2.17, p = .028, ηp2 = .030); however, these relationships did not remain significant after correction for covariates (Fs < 1.53, ps > .145, ηp2s < .032). Conclusions: We did not find evidence of a relationship between LBE and neurocognitive performance or psychiatric symptoms. This stands in contrast to prior studies demonstrating an association between lifetime blast exposure and highly sensitive blood biomarkers and/or neuroimaging. Overall, findings suggest the neuropsychological impact of lifetime blast exposure is minimal in individuals remaining in or recently retired from military service. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to examine whether blood-based biomarkers associate with neurobehavioral functioning at three time points following traumatic brain injury (TBI). Materials and methods: Participants were 328 United States service members and veterans (SMVs) prospectively enrolled in the Defense and Veterans Brain Injury Center-Traumatic Brain Injury Center of Excellence (DVBIC-TBICoE) 15- Year Longitudinal TBI Study, recruited into three groups: uncomplicated mild TBI (MTBI, n = 155); complicated mild, moderate, severe TBI combined (STBI, n = 97); non-injured controls (NIC, n = 76). Participants were further divided into three cohorts based on time since injury (≤12 months, 3–5 years, and 8–10 years). Participants completed the Minnesota Multiphasic Personality Inventory-2- Restructured Format (MMPI-2-RF) and underwent blood draw to measure serum concentrations of glial fibrillary acidic protein (GFAP), neurofilament light (NfL), and tau. A total of 11 MMPI-2-RF scales were examined (e.g., depression, anxiety, anger, somatic, cognitive symptoms). Stepwise hierarchical regression models were conducted within each group. Results: Significant associations were found between biomarkers and MMPI-2- RF scales (all p < 0.05; R2Δ > 0.10). GFAP was inversely related to (a) neurological complaints in the MTBI group at ≤12 months, (b) demoralization, anger proneness in the STBI group at ≤12 months, and (c) head pain complaints in the STBI group at 8–10 years. NfL was (a) related to low positive emotions in the NIC group; and inversely related to (b) demoralization, somatic complaints, neurological complaints, cognitive complaints in the MTBI group at ≤12 months, (c) demoralization in the STBI group at ≤12 months, and (d) demoralization, head pain complaints, stress/worry in the STBI group at 3–5 years. In the STBI group, there were meaningful findings (R²Δ > 0.10) for tau, NFL, and GFAP that did not reach statistical significance. Discussion: Results indicate worse scores on some MMPI-2-RF scales (e.g., depression, stress/worry, neurological and head pain complaints) were associated with lower concentrations of serum GFAP, NfL, and tau in the sub- acute and chronic phase of the recovery trajectory up to 5 years post-injury, with a reverse trend observed at 8–10 years. Longitudinal studies are needed to help elucidate any patterns of association between blood-based biomarkers and neurobehavioral outcome over the recovery trajectory following TBI. [ABSTRACT FROM AUTHOR]

The extant literature investigating the relationship between diffusion tensor imaging (DTI) and cognition following traumatic brain injury (TBI) is limited by small sample sizes and inappropriate control groups. The present study examined DTI metric differences between service members and veterans (SMVs) with bodily injury (Trauma Control; TC), uncomplicated mild TBI (mTBI), complicated mild TBI (compTBI), and severe-moderate TBI combined (smTBI), and how DTI metrics related to cognition within each group. Participants were 226 SMVs (56 TC, 112 mTBI, 29 compTBI, 29 smTBI) with valid neuropsychological testing and DTI at least 11 months post-injury. The smTBI group demonstrated decreased fractional anisotropy (FA) and increased axial diffusivity (AD), mean diffusivity (MD), and radial diffusivity (RD) of the cerebral white matter (CWM) and several individual white matter tracts compared with the TC, mTBI, and compTBI groups (all ps < 0.05; rs = 0.17 to 0.49). The TC, mTBI, and compTBI groups did not differ in terms of any DTI metrics. Within the smTBI group, FA, AD, MD, and RD of the total CWM and several white matter tracts were related to Processing Speed (|rs|: 0.43 to 0.66; ps < 0.05), and/or Delayed Memory (|rs|: 0.41 to 0.67; ps < 0.05). In the compTBI group, Processing Speed was related to left arcuate fasciculus and superior longitudinal fasciculus (SLF) FA, MD, and RD, as well as left uncinate fasciculus MD and RD. In contrast, there were no significant relationships between DTI metrics and cognition/emotional functioning within the mTBI or TC groups. Overall, findings suggest a dose-response relationship between TBI severity and the strength of the relationship between white matter integrity and cognitive performance, with essentially no relationship in mTBI, some findings in compTBI, and several strongly significant relationships in smTBI. In contrast to previously reported findings, there were no differences in DTI metrics between controls, mTBI, and compTBI, and DTI metrics were unrelated to cognition in our relatively large mTBI group. [ABSTRACT FROM AUTHOR]

Objective: Physical therapy following traumatic brain injury (TBI) can be negatively impacted by psychological symptoms, atypical symptom reporting, and response bias. We examined rates of Symptom Validity Test (SVT) failure in active duty military service members with a history of mild-moderate TBI and its impact on gait speed. Setting: Intensive Outpatient Program at the National Intrepid Center of Excellence at Walter Reed National Military Medical Center. Participants: Participants were 84 active duty service members with a history of mild-moderate TBI classified as SVT pass (n = 49) or SVT fail (n = 35). Design: Retrospective study. Main Measures: Overground preferred and fast walking speed as well as Computer Assisted Rehabilitation Environment (CAREN) gait speed were recorded. Participants completed the Neurobehavioral Symptom Inventory and the Validity-10 was used to assign patients into the SVT pass and SVT fail groups. Gait speed metrics were compared across these groups and test operating characteristics were calculated. Results: Approximately 42% of the sample was classified into the SVT fail group. All 3 gait speed measures were significantly slower in the SVT fail group than in the SVT pass group (P s <.001, d s = 0.60-0.80). Gait speed cutoffs for screeners or indicators of atypical reporting were identified. Conclusions: The potential for response bias is a critical area for the clinician to consider when conducting physical therapy evaluations. Participants in the SVT fail group had slower walking speed on all 3 measures assessed. Several useful cutoffs were identified to serve as screeners or indicators of SVT failure, though these preliminary findings have limitations and need to be replicated. [ABSTRACT FROM AUTHOR]

Background and Objectives: APOE e4 has been linked to poor outcome following traumatic brain injury (TBI); however, the mechanisms behind this relationship are unclear. Few studies have investigated the relationship between the APOE genotype and established brain related protein biomarkers following TBI. The purpose of this study was to examine this relationship in service members and veterans (SMVs) following TBI. Methods: Participants were 209 SMVs [124 uncomplicated mild TBI (mTBI); 85 complicated mild, moderate, severe, or penetrating TBI (mod-sev TBI)] prospectively enrolled in the DVBIC-TBICoE 15-Year Longitudinal TBI Study. APOE genotyping was undertaken using non-fasting blood serum samples. Participants were divided into three groups: APOE e2+, APOE e3/e3, and APOE e4+. Results: In participants with mTBI, those with the APOE e2 allele had significantly lower levels of tau than those with APOE e4 (p = 0.005, r = 0.43, medium-large effect size). Those with APOE e3/e3 trended toward having higher tau than those APOE e2+ (p = 0.076, r = 0.20, small-medium effect size) and lower tau than those with APOE e4+ (p = 0.062, r = 0.21, small-medium effect size). There were no significant differences in biomarkers based on APOE in the mod-sev TBI group. Discussion: This study is the first to demonstrate APOE genotype is related to serum tau levels following a mTBI, extending prior findings to human serum following mTBI. In addition to higher serum tau levels in APOE e4 carriers, lower tau levels were observed in APOE e2 carriers, suggesting a possible protective effect. [ABSTRACT FROM AUTHOR]

Although post-traumatic stress disorder (PTSD) has been associated with worse cognitive outcomes after mild traumatic brain injury (TBI), its impact has not been evaluated after more severe TBI. This study aimed to determine whether PTSD symptoms are related to cognition after complicated mild, moderate, severe, and penetrating TBI. Service members (n = 137) with a history of complicated mild/moderate TBI (n = 64) or severe/penetrating TBI (n = 73) were prospectively enrolled from United States Military Treatment Facilities. Participants completed a neuropsychological assessment one year or more post-injury. Six neuropsychological composite scores and an overall test battery mean (OTBM) were considered. Participants were excluded if there was evidence of invalid responding. Hierarchical linear regressions were conducted evaluating neuropsychological performance. The interaction between TBI severity and PTSD Checklist-Civilian version total score was significant for processing speed (β = 0.208, p = 0.034) and delayed memory (β = 0.239, p = 0.021) and trended toward significance for immediate memory (β = 0.190, p = 0.057) and the OTBM (β = 0.181, p = 0.063). For each of these composite scores, the relationship between PTSD symptoms and cognition was stronger in the complicated mild/moderate TBI group than the severe/penetrating TBI group. Within the severe/penetrating TBI group, PTSD symptoms were unrelated to cognitive performance. In contrast, within the complicated mild/moderate TBI group, PTSD symptoms were significantly related to processing speed (R2Δ = 0.077, β = -0.280, p = 0.019), immediate memory (R2Δ = 0.197, β = -0.448, p < 0.001), delayed memory (R2Δ = 0.176, β = -0.423, p < 0.001), executive functioning (R2Δ = 0.100, β = -0.317, p = 0.008), and the OTBM (R2Δ = 0.162, β = -0.405, p < 0.001). The potential impact of PTSD symptoms on cognition, over and above the impact of brain injury alone, should be considered with service members and veterans with a history of complicated mild/moderate TBI. In addition, in research comparing cognitive outcomes between patients with histories of complicated-mild, moderate, severe, and/or penetrating TBI, it will be important to account for PTSD symptoms. [ABSTRACT FROM AUTHOR]

Objective: This study examines the relationship of serum total tau, neurofilament light (NFL), ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), and glial fibrillary acidic protein (GFAP) with neurocognitive performance in service members and veterans with a history of traumatic brain injury (TBI). Method: Service members (n = 488) with a history of uncomplicated mild (n = 172), complicated mild, moderate, severe, or penetrating TBI (sTBI; n = 126), injured controls (n = 116), and non-injured controls (n = 74) prospectively enrolled from Military Treatment Facilities. Participants completed a blood draw and neuropsychological assessment a year or more post-injury. Six neuropsychological composite scores and presence/absence of mild neurocognitive disorder (MNCD) were evaluated. Within each group, stepwise hierarchical regression models were conducted. Results: Within the sTBI group, increased serum UCH-L1 was related to worse immediate memory and delayed memory (R2Δ =.065–.084, ps <.05) performance, while increased GFAP was related to worse perceptual reasoning (R2Δ =.030, p =.036). Unexpectedly, within injured controls, UCH-L1 and GFAP were inversely related to working memory (R2Δ =.052–.071, ps <.05), and NFL was related to executive functioning (R2Δ =.039, p =.021) and MNCD (Exp(B) = 1.119, p =.029). Conclusions: Results suggest GFAP and UCH-L1 could play a role in predicting poor cognitive outcome following complicated mild and more severe TBI. Further investigation of blood biomarkers and cognition is warranted. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine long-term neurobehavioural symptom reporting following mild, moderate, severe, or penetrating TBI in U.S. military service members and veterans (SMV). Participants were 445 SMVs divided into four groups: 158 uncomplicated mild TBI ("unMTBI" group), 105 penetrating, severe, moderate, or complicated mild TBI ("smcTBI" group), 101 injured controls (IC), and 81 non-injured controls (NIC). Two independent cohorts were examined that included participants 5-years or 10-year post-injury. Participants completed the TBI-Quality of Life, Neurobehavioural Symptom Inventory, and Post-traumatic Stress Disorder Checklist. At 5-years and 10-years post-injury, there were significant main effects for the majority of measures (all p's < .005). At 10-years post-injury, the NIC group had consistently better scores compared to the IC, unMTBI, and smcTBI groups. At 5-years post-injury, either (a) the IC and NIC group had better scores compared to both TBI groups, or (b) the NIC group had better scores compared to the IC, unMTBI, and smcTBI groups. A high proportion of SMVs reported poor long-term neurobehavioural symptoms following TBI or bodily injury without TBI. Injured SMVs (regardless of injury type) can have long-term symptoms that impact mental health and overall quality of life requiring long-term follow-up and care. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine individual postconcussion symptom [PCSx] trajectories following mild traumatic brain injury (MTBI), and to examine risk factors for persistent PCSx reporting. Participants were 138 U.S. military service members and veterans (SMVs) prospectively enrolled in the Defense and Veterans Brain Injury Center, 15-Year Longitudinal TBI study. Participants were classified into three groups: uncomplicated MTBI (n = 54), injured controls (IC, n = 26), and non-injured controls (NIC, n = 58). Participants completed the Neurobehavioral Symptom Inventory, PTSD Checklist, and Traumatic Brain Injury Quality of Life at baseline (<8 months post-injury) and at follow-up (2–4 years post-injury). The prevalence of those who met DSM-IV-TR symptom criteria for Postconcussional Disorder (PCD) was high in all three groups (e.g., 44.8–63.0%) and did not significantly change from baseline to follow-up (all ps>.05). However, there was substantial variability in individual symptom trajectories over time. The majority of participants had symptom trajectories classified as either 'persistent' (∼32–55%) or 'asymptomatic' (∼30–36%), with a substantial minority classified as 'improved' (∼7–12%) or 'developed' (∼7–19%). Factors associated with 'persistent' PCD trajectories included cognitive complaints, PTSD, depression, anxiety, pain, and headaches at baseline; but not the presence/absence of MTBI. Factors associated with 'developed' PCD trajectories included PTSD and the number of lifetime exposures to blast. Conclusions: Reporting of 'new' PCSx over time was common in individuals with and without MTBI. It would be erroneous to assume uncritically that PCSx reported many years post-injury reflect only persistent symptomatology, or can be solely attributable to the direct consequences of a brain injury. [ABSTRACT FROM AUTHOR]

The objective of the study was to examine long-term neuropsychological outcome after moderate, severe, and penetrating traumatic brain injury (TBI) in U.S. military service members and veterans (SMVs). Eighty-five SMVs with a history of moderate (n = 18), severe (n = 17), or penetrating (n = 26) TBI, or an injury without TBI (i.e., trauma control [TC], n = 24) were assessed five or more years (mean = 69.4 months; standard deviation = 35.6) post-injury. All passed performance validity tests. Participants completed a battery of neurocognitive tests and a personality inventory. Five cognitive domain composites, each composed of four test scores, and an overall test battery mean (OTBM) were computed. The penetrating TBI group performed worse than the TC group and/or the moderate TBI group on most cognitive domains and the OTBM. The severe TBI group also performed worse than the TC group and moderate TBI group on processing speed and the OTBM, and worse than the TC group on attention/working memory. Just more than half of participants with severe (56%) or penetrating (64%) TBI met criteria for mild neurocognitive disorder, with processing speed the most commonly impaired domain. In addition, 80% of TBI participants had one or more clinically elevated scales on the Minnesota Multiphasic Personality Inventory-2-Restructured Form® (MMPI-2-RF), with somatic complaints the most common elevation. In conclusion, there was significantly reduced cognitive and psychological functioning many years after severe and penetrating TBI in SMVs. Cognitive and psychological dysfunction, however, were highly variable, with a substantial minority of SMVs having good outcome. Long-term individualized support is necessary for individuals after moderate, severe, and penetrating TBI. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the relationship between plasma tau and amyloid beta-42 (Aβ42), neuropsychological functioning, and white matter integrity in U.S. military service members with (n = 155) and without (n = 42) a history of uncomplicated mild (n = 83), complicated mild (n = 26), or moderate, severe, or penetrating (n = 46) traumatic brain injury (TBI). We hypothesized that higher levels of tau and Aβ42 would be related to reduced neurocognitive performance and white matter integrity. Participants were enrolled prospectively from Walter Reed National Military Medical Center. Participants completed a blood draw, neuropsychological assessment, and diffusion tensor imaging (General Electric 3T) of the whole brain. From 20 neuropsychological test scores, five cognitive domain scores were computed. Measures of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were generated for 18 regions of interest (ROIs). There was no relationship found between the plasma biomarkers and neurocognitive performance in any of the three TBI groups (all ps >0.05; all R2 changes <0.146). Although not reaching statistical significance after correction for multiple comparisons, higher tau and Aβ42 tended to be related to higher FA and lower MD, RD, and AD in patients with a history of moderate, severe, or penetrating TBI. There was no consistent relationship between either of the biomarkers and white matter integrity in the complicated and uncomplicated mild TBI groups. In addition, there was no significant relationship between the biomarkers and age, education, sex, race, bodily injury severity, time since injury, TBI severity, or number of TBIs (all ps >0.15). Future investigation in larger samples of moderate, severe, and penetrating TBI are needed. Other plasma biomarkers, including phosphorylated tau, exosomal tau, and interleukin-10, may be more promising measures to use in the diagnosis, management, and treatment of TBI. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to examine the relation between white matter integrity of the brain and postconcussion symptom reporting following mild traumatic brain injury (MTBI). Method: Participants were 109 U.S. military service members (91.7% male) who had sustained a MTBI (n = 88) or orthopedic injury without TBI (trauma controls, TC, n = 21), enrolled from the Walter Reed National Military Medical Center, Bethesda, Maryland. Participants completed a battery of neurobehavioral symptom measures and underwent diffusion tensor imaging (DTI; General Electric 3T) of the whole brain, on average 44.9 months post injury (SD = 42.3). Measures of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were generated for 18 regions of interest (ROIs). Participants in the MTBI group were divided into two subgroups based on International Classification of Diseases–10th Revision (ICD–10) Category C criteria for postconcussion syndrome (PCS): PCS-present (n = 41) and PCS-absent (n = 47). Results: The PCS-present group had significantly worse scores on all 13 neurobehavioral measures than the PCS-absent group (p <.001, d = 0.87–2.50) and TC group (p <.003, d = 0.84–2.06). For all ROIs, there were no significant main effects across the three groups for FA, MD, AD, and RD (all ps >.03). Pairwise comparisons revealed no significant differences for all ROIs when using FA and RD, and only two significant pairwise differences were found between PCS-present and PCS-absent groups when using MD and AD [i.e., anterior thalamic radiation and cingulate gyrus (supracallosal) bundle]. Conclusions: Consistent with past research, but not all studies, postconcussion symptom reporting was not associated with white matter integrity in the subacute to chronic phase of recovery following MTBI. [ABSTRACT FROM AUTHOR]

This study examined the impact of service member/veteran (SMV) combat deployment and traumatic brain injury (TBI) on the health and behavior of his or her children. Participants were 104 female spouse caregivers of US SMVs who had sustained a mild, severe, or penetrating TBI. Participants completed the Children’s Health and Behavior Questionnaire (CHBQ; r = .758 to .881) that evaluates school grades, behavior, medical health, emotional health, and social participation: (a) prior to the first combat deployment, (b) in the month prior to the TBI, (c) within 2 years after the TBI, and (d) 2 or more years after the TBI. A substantial number of children experienced a decline in health and behavior following the TBI (41.7%–79.1%). Of those who declined (a) 68.8%–75.5% declined within the first 2 years post-injury, followed by improvement or stabilization; (b) 6.7%–15.6% declined only after 2 or more years post-injury; (c) 15.6%–25.0% declined within the first 2 years post-injury and then again 2 or more years post-injury; and (d) 16.9%–26.5% experienced a decline as a result of deployment, followed by an additional decline after the SMV’s TBI. Services are required for children of SMVs following TBI and deployment, particularly children at risk for poor outcome. [ABSTRACT FROM AUTHOR]

Objective: Examine effects of diagnostically relevant posttraumatic stress disorder (PTSD) symptoms, mild traumatic brain injury (TBI) severity, and associated bodily injury severity on postconcussion symptom reporting in female service members (SM) compared with a matched sample of male SM. Setting: Six US military medical treatment facilities. Participants: A total of 158 SM (79 females, 79 males) evaluated within 30 months after mild TBI. Men and women were matched by age, days postinjury, PTSD symptom status, mild TBI severity, and bodily injury severity. All passed a measure of symptom validity. Design: Compare reported postconcussion symptoms for men and women stratified by PTSD diagnostic symptoms (present/absent), mild TBI severity (alteration of consciousness/loss of consciousness), and bodily injury severity (mild/moderate-severe). Main Measures: Neurobehavioral Symptom Inventory, PTSD Checklist, Abbreviated Injury Scale. Results: Overall postconcussion symptom reporting increased with PTSD but did not significantly differ based on severity of mild TBI or associated bodily injury. Females reported more somatosensory and/or vestibular symptoms than males under some circumstances. Females in the PTSD-Present group, Alteration of Consciousness Only group, and Moderate-Severe Bodily Injury group reported more somatosensory symptoms than males in those groups. Females in the Alteration of Consciousness Only group and Minor Bodily Injury group reported more vestibular symptoms than males in those groups. Conclusion: Diagnostically relevant PTSD symptoms, mild TBI severity, and bodily injury severity differentially impact somatosensory and vestibular postconcussion symptom reporting for male and female SM after mild TBI. Controlling for PTSD and symptom validity resulted in fewer gender-based differences in postconcussive symptoms than previously demonstrated in the literature. [ABSTRACT FROM AUTHOR]

Females are often excluded from military-related mild traumatic brain injury (mTBI) research because of its relatively low prevalence in this population. The purpose of this study was to focus on outcome from mTBI in female service members, compared with males. Participants were 172 United States military service members selected from a larger sample that had sustained an mTBI, and were evaluated within 24 months of injury (Age: mean = 28.9, SD= 8.1) at one of six military medical centers. Eighty-six women were matched to 86 men on nine key variables: TBI severity, mechanism of injury, bodily injury severity, days post-injury, age, number of deployments, theater where wounded, branch of service, and rank. Participants completed the Neurobehavioral Symptom Inventory (NSI) and the Posttraumatic Stress Disorder Checklist (PCL-C). There were no meaningful gender differences across all demographic and injury-related variables ( p > 0.05). There were significant group differences and medium effect sizes for the NSI total score and all four NSI cluster scores. Symptoms most affected related to nausea, sensitivity to light, change in taste/smell, change in appetite, fatigue, and poor sleep. There were significant group differences and small-medium effect sizes for the PCL-C total score and two of the three PCL-C cluster scores. Symptoms most affected related to poor concentration, trouble remembering a stressful event, and disturbing memories/ thoughts/images. Females consistently experienced more symptoms than males. As females become more active in combatrelated deployments, it is critical that future studies place more emphasis on this important military population. [ABSTRACT FROM AUTHOR]

Introduction: The Mild Brain Injury Atypical Symptoms (mBIAS) scale was developed as a symptom validity test (SVT) for use with patients following mild traumatic brain injury. This study was the first to examine the clinical utility of the mBIAS in a mixed clinical sample presenting to a Department of Veterans Affairs (VA) neuropsychology clinic.Method: Participants were 117 patients with mixed etiologies (85.5% male; age:M= 39.2 years,SD= 11.6) from a VA neuropsychology clinic. Participants were divided into pass/fail groups using two different SVT criteria, based on select validity scales from the Minnesota Multiphasic Personality Inventory–2 (MMPI–2): first, Infrequency Scale (F) scores: (a) MMPI–F–Fail (n= 21) and (b) MMPI–F–Pass (n= 96); and, second, Symptom Validity Scale (FBS) scores: (a) MMPI–FBS–Fail (n= 36) and (b) MMPI–FBS–Pass (n= 81).Results: The mBIAS demonstrated good internal consistency, and each item contributed meaningfully to the total score. At a symptom exaggeration base rate of 35%, an mBIAS cutoff of ≥11 was optimal for screening symptom exaggeration when groups were classified using both F and FBS scales. This cutoff score resulted in very high specificity (.89 to .94); moderate–high positive predictive power (.71 to .75) and negative predictive power (.72 to .79); and low–moderate sensitivity (.31 to .57). At all base rates of probable somatic exaggeration, a cutoff of ≥16 resulted in perfect specificity and positive predictive power, but very low sensitivity.Conclusions: The mBIAS has potential for use in samples outside of mild traumatic brain injury. In settings where the symptom exaggeration base rate is 35%, a cutoff of ≥11 may be used as a “red flag” for further evaluation, but should not be relied on for clinical decision making. At all base rates of probable somatic exaggeration, psychologists with patients who score ≥16 can be confident that those patients were exaggerating. Importantly, however, this cutoff may fail to identify a large proportion of patients who are exaggerating. [ABSTRACT FROM PUBLISHER]

The Validity-10 scale was recently developed to screen for symptom exaggeration in patients following traumatic brain injury (TBI). However, it has only been validated on patients with TBI largely in the chronic phase of recovery. The influence of time since injury on the Validity-10 scale was investigated in 2,661 male servicemembers with TBI presenting to six U.S. Defense and Veterans Brain Injury Centers. Participants completed the Neurobehavioral Symptom Inventory (NSI). The Validity-10 scale and NSI total score were both weakly statistically significantly (1) positively correlated with time since injury, (2) negatively correlated with bodily injury severity, and (3) higher in participants undergoing medical board evaluations than in participants who returned to duty or were still hospitalized. Participants were statistically more likely to screen positive for possible symptom exaggeration on the Validity-10 scale as time since injury increased. However, the Validity-10 scale was only weakly related to time since injury, TBI severity, bodily injury severity, disposition, age, and return to duty status. That false positives are not increased in the acute phase of recovery and that the Validity-10 scale is not strongly related to clinical factors support the use of the Validity-10 scale in the acute recovery phase and across the TBI recovery trajectory. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the clinical utility of three recently developed validity scales (Validity-10, NIM5, and LOW6) designed to screen for symptom exaggeration using the Neurobehavioral Symptom Inventory (NSI). Participants were 272 U.S. military service members who sustained a mild, moderate, severe, or penetrating traumatic brain injury (TBI) and who were evaluated by the neuropsychology service at Walter Reed Army Medical Center within 199 weeks post injury. Participants were divided into two groups based on the Negative Impression Management scale of the Personality Assessment Inventory: (a) those who failed symptom validity testing (SVT-fail; n = 27) and (b) those who passed symptom validity testing (SVT-pass; n = 245). Participants in the SVT-fail group had significantly higher scores (p<.001) on the Validity-10, NIM5, LOW6, NSI total, and Personality Assessment Inventory (PAI) clinical scales (range: d = 0.76 to 2.34). Similarly high sensitivity, specificity, positive predictive power (PPP), and negative predictive (NPP) values were found when using all three validity scales to differentiate SVT-fail versus SVT-pass groups. However, the Validity-10 scale consistently had the highest overall values. The optimal cutoff score for the Validity-10 scale to identify possible symptom exaggeration was ≥19 (sensitivity =.59, specificity =.89, PPP =.74, NPP =.80). For the majority of people, these findings provide support for the use of the Validity-10 scale as a screening tool for possible symptom exaggeration. When scores on the Validity-10 exceed the cutoff score, it is recommended that (a) researchers and clinicians do not interpret responses on the NSI, and (b) clinicians follow up with a more detailed evaluation, using well-validated symptom validity measures (e.g., Minnesota Multiphasic Personality Inventory–2 Restructured Form, MMPI–2–RF, validity scales), to seek confirmatory evidence to support an hypothesis of symptom exaggeration. [ABSTRACT FROM AUTHOR]

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

The purpose of this study was to examine the association between the apolipoprotein E (APOE) ε4 allele and neurocognitive functioning following traumatic brain injury (TBI) in military service members and veterans (SMVs). Participants included 176 SMVs with a history of remote TBI (≥1 year post-injury), categorized into mild (n = 100), moderate (n = 40), and severe (n = 36) TBI groups. Participants completed a neuropsychological assessment and APOE genotyping (n = 46 ε4+, n = 130 ε4-). Neurocognitive composite scores representing memory, executive functioning, and visual processing speed were computed. ANCOVAs adjusting for race, education, combat exposure, and PTSD symptom severity showed a significant main effect of ε4 on the memory composite, such that ε4+ SMVs exhibited poorer memory performance than ε4- SMVs. When ε2 allele carriers were removed from the analyses, associations with memory were strengthened, demonstrating a possible protective effect of the ε2 allele. No main effect of TBI group was identified on any cognitive composite, nor were there any significant TBI group × ε4 status interactions for any cognitive composite. Future studies with larger samples are needed to verify these findings, but our results suggest an important relationship between ε4 status and memory functioning following remote TBI of all severities. [ABSTRACT FROM AUTHOR]

Purpose/Objective: To (a) examine the factor structure of the original 47-item Caregiver Appraisal Scale (CAS) in caregivers of service members/veterans (SMVs) following traumatic brain injury (TBI) and (b) assess whether the CAS yields a similar factor structure in this population compared to caregivers of civilian adults following TBI. Research Method/Design: Participants were 287 caregivers (female = 96.2%; spouse = 87.8%; mean age = 38.6 years) of SMVs who sustained a mild, moderate, severe, or penetrating TBI, recruited from Walter Reed National Military Medical Center and via caregiver community outreach. Caregivers completed the CAS, Caregiver Questionnaire, and Mayo-Portland Adaptability Inventory-4 upon enrollment in the study. Results: Principal component analysis (PCA) revealed four factors that explained 43.2% of the variance in CAS scores: Perceived Burden, Caregiving Relationship Satisfaction, Caregiving Ideology, and Caregiving Mastery. Thirty-seven of the 47 CAS items loaded significantly onto only one of the four factors (≥.40). A secondary PCA was performed on these 37 items, resulting in a four-factor solution very similar to that of the 47-item solution, which explained 46.8% of the variance in the 37-item measure. All but one item loaded significantly on a factor corresponding to a conceptually similar construct. Conclusions/Implications: Military and civilian caregivers have overlapping and differing concerns. The findings support a 37-item four-factor model of caregiving stress appraisal that has the potential for use as an outcome measure for developing caregiver interventions. It may be as useful to administer a reduced 37-item measure of the CAS to caregivers as the original 47-item measure, but further development is required. [ABSTRACT FROM AUTHOR]

• The APOE e4 allele was associated with worse neurobehavioral functioning following mild traumatic brain injury. • Areas most affected related to depression, pain, anxiety, grief, positive well-being, social participation, and resilience. • APOE may be a valuable screening tool to target 'at risk' service members and veterans for poor long-term neurobehavioral outcome following mild traumatic brain injury. Past research has found a relationship between the apolipoprotein E (APOE) e4 allele and worse neurobehavioral functioning following mild traumatic brain injury (MTBI) in civilian populations. The purpose of this study was to examine this relationship in service members and veterans (SMVs) following MTBI. Participants were 151 SMVs (103 uncomplicated MTBI; 48 Injured Controls [IC]) prospectively enrolled in the DVBIC-TBICoE 15-Year Longitudinal TBI Study. Participants completed a battery of self-reported neurobehavioral symptom measures on average 76.2 months post-injury (SD = 31.8). APOE genotyping was undertaken using non-fasting blood samples. Participants were classified into four subgroups based on injury (MTBI vs. IC) and APOE e4 allele status (e4 present/absent). In the IC group, there were no significant differences across APOE e4 status subgroups for all measures. In the MTBI group, participants with the APOE e4 allele had significantly worse scores on measures of depression, pain, anxiety, grief, positive well-being, social participation, and resilience compared to those without the e4 allele (d =.44 to d =.69). When comparing the number of 'clinically elevated' neurobehavioral measures simultaneously, the MTBI/e4 present subgroup consistently had a higher number of elevated measures compared to the MTBI/e4 absent, IC/e4 present, and IC/e4 absent subgroups. The APOE e4 allele was associated with poorer neurobehavioral outcome in SMVs in the chronic phase of recovery following MTBI. APOE e4 could be incorporated into screening tools to predict SMVs at risk for poor long-term neurobehavioral outcome in an effort to provide early intervention to improve long-term clinical outcome. [ABSTRACT FROM AUTHOR]