Concurrent posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) is common in military populations. The purpose of this study was to examine long‐term neurobehavioral outcomes in ...service members and veterans (SMVs) with versus without PTSD symptoms following TBI of all severities. Participants were 536 SMVs prospectively enrolled from three military medical treatment facilities who were recruited into three experimental groups: TBI, injured controls (IC), and noninjured controls (NIC). Participants completed the PTSD Checklist, Neurobehavioral Symptom Inventory, and the TBI–Quality of Life (TBI‐QOL) and were divided into six subgroups based on the three experimental categories, two PTSD categories (i.e., present vs. absent), and two broad TBI severity categories (unMTBI, which included uncomplicated mild TBI; and smcTBI, which included severe TBI, moderate TBI, and complicated mild TBI): (a) NIC/PTSD‐absent, (b) IC/PTSD‐absent, (c) unMTBI/PTSD‐absent, (d) unMTBI/PTSD‐present, (e) smcTBI/PTSD‐absent, and (f) smcTBI/PTSD‐present. There were significant main effects across the six groups for all TBI‐QOL measures, ps < .001. Select pairwise comparisons revealed significantly lower scores, p < .001, on all TBI‐QOL measures in the PTSD‐present groups when compared to the PTSD‐absent groups within the same TBI severity classification, ds = 0.90–2.11. In contrast, when controlling for PTSD, there were no significant differences among the TBI severity groups for any TBI‐QOL measures. These results provide support for the strong influence of PTSD but not TBI severity on neurobehavioral outcomes following TBI. Concurrent PTSD and TBI of all severities should be considered a risk factor for poor long‐term neurobehavioral outcomes that require ongoing monitoring.
Neuromotor dysfunction after a concussion is common, but balance tests used to assess neuromotor dysfunction are typically subjective. Current objective balance tests are either cost- or ...space-prohibitive, or utilize a static balance protocol, which may mask neuromotor dysfunction due to the simplicity of the task. To address this gap, our team developed an Android-based smartphone app (portable and cost-effective) that uses the sensors in the device (objective) to record movement profiles during a stepping-in-place task (dynamic movement). The purpose of this study was to examine the extent to which our custom smartphone app and protocol could discriminate neuromotor behavior between concussed and non-concussed participants. Data were collected at two university laboratories and two military sites. Participants included civilians and Service Members (N = 216) with and without a clinically diagnosed concussion. Kinematic and variability metrics were derived from a thigh angle time series while the participants completed a series of stepping-in-place tasks in three conditions: eyes open, eyes closed, and head shake. We observed that the standard deviation of the mean maximum angular velocity of the thigh was higher in the participants with a concussion history in the eyes closed and head shake conditions of the stepping-in-place task. Consistent with the optimal movement variability hypothesis, we showed that increased movement variability occurs in participants with a concussion history, for which our smartphone app and protocol were sensitive enough to capture.
Sub-concussive injuries have emerged as an important factor in the long-term brain health of athletes and military personnel. The objective of this study was to explore the relationship between ...service member and veterans (SMVs) lifetime blast exposure and recovery from a traumatic brain injury (TBI). A total of 558 SMVs with a history of TBI were examined. Lifetime blast exposure (LBE) was based on self-report (M = 79.4, standard deviation = 392.6; range = 0-7500) categorized into three groups: Blast Naive (
= 121), Low LBE (
= 223; LBE range 1-9), and High LBE (
= 214; LBE >10). Dependent variables were the Neurobehavioral Symptom Inventory (NSI) and Post-traumatic Stress Disorder Checklist-Civilian (PCL-C) and the Traumatic Brain Injury Quality of Life (TBI-QOL). Analyses controlled for demographic factors (age, gender, and race) as well as TBI factors (months since index TBI, index TBI severity, and total number lifetime TBIs). The Blast Naive group had significantly lower NSI and PCL-C scores compared with the Low LBE group and High LBE group, with small to medium effect sizes. On the TBI-QOL, the Blast Naïve group had better quality life on 10 of the 14 scales examined. The Low LBE did not differ from the High LBE group on the PCL-C, NSI, or TBI-QOL. Blast exposure over an SMV's career was associated with increased neurobehavioral and post-traumatic stress symptoms following a TBI. The influence of psychological trauma associated with blasts may be an important factor influencing symptoms as well as the accuracy of self-reported estimates of LBE.
Abstract
Objective
Mild traumatic brain injury (mTBI) is common among warfighters. Most have a full recovery but some have persistent cognitive complaints. Cognitive rehabilitation is the primary ...treatment; however, mTBI is highly co-morbid with depression and post-traumatic stress (PTS). This study investigated if high levels of mental health symptoms negatively impacted the efficacy of cognitive rehabilitation.
Methods
82 military personnel with at least one diagnosed mTBI and persistent cognitive complaints completed 4–6 weeks of cognitive rehabilitation. PTS was measured by the Post-Traumatic Checklist-5 (PCL-5) and depression was measured with the Patient Health Questionnaire 8 (PHQ8); scores were dichotomized based on published cut-offs (>33 and > 10, respectively). Outcomes included change pre-post treatment on: Neurobehavioral Scale Inventory (NSI), Key Behavior Change Index (KBCI), and Global Deficit Scale (GDS). GDS was derived from: Hopkins Verbal Learning Test-Revised, Color Word, Trail Making, Paced Auditory Serial Addition Test, and the Symbol Digit Modality Test.
Results
A MANOVA revealed PTS had no effect on the NSI, KBCI, or GDS (p = 0.659). There was a significant effect for depression (p = 0.017); however, this was specific to change in GDS (p = 0.002). The average reduction was 0.98 (SD = 0.87) in high depression and 0.43 (SD = 0.68) in low depression. Depression did not impact NSI or KBCI.
Conclusion
In contrast to the initial hypothesis, high levels of depression or PTS did not negatively impact the efficacy of cognitive rehabilitation. In fact, warfighters with high levels of depression had greater improvements in cognitive functioning.
Purpose
This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting future ...neurobehavioral outcome following traumatic brain injury (TBI).
Methods
Participants were 591 U.S. military service members and veterans who had sustained a TBI (
n
= 419) or orthopedic injury without TBI (
n
= 172). Participants completed the Neurobehavioral Symptom Inventory, PTSD Checklist, and the TBI-Quality of Life (TBI-QOL) scale at baseline and follow-up.
Results
Using the four risk factors at baseline, 15 risk factor combinations were examined by calculating odds ratios to predict poor neurobehavioral outcome at follow-up (i.e., number of abnormal scores across five TBI-QOL scales e.g., Fatigue, Depression). The vast majority of risk factor combinations resulted in odds ratios that were considered to be clinically meaningful (i.e., ≥ 2.5) for predicting poor outcome. The risk factor combinations with the highest odds ratios included PTSD singularly, or in combination with poor sleep and/or low resilience (odds ratios = 4.3–72.4). However, poor sleep and low resilience were also strong predictors in the absence of PTSD (odds ratios = 3.1–29.8).
Conclusion
PTSD, poor sleep, and low resilience, singularly or in combination, may be valuable risk factors that can be used clinically for targeted early interventions.
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 combat-related deployments, it is critical that future studies place more emphasis on this important military population.
The purpose of this cross-sectional study was to examine the influence of subthreshold posttraumatic stress disorder (PTSD) and full PTSD on quality of life following mild traumatic brain injury ...(mTBI).
Participants were 734 service members and veterans (SMV) classified into two injury groups: uncomplicated mild TBI (MTBI; n = 596) and injured controls (IC, n = 139). Participants completed a battery of neurobehavioral measures, 12-or-more months post-injury, that included the PTSD Checklist Civilian version, Neurobehavioral Symptom Inventory, and select scales from the TBI-QOL and MPAI. The MTBI group was divided into three PTSD subgroups: No-PTSD (n = 266), Subthreshold PTSD (n = 139), and Full-PTSD (n = 190).
There was a linear relationship between PTSD severity and neurobehavioral functioning/quality of life in the MTBI sample. As PTSD severity increased, significantly worse scores were found on 11 of the 12 measures (i.e., MTBI: Full-PTSD > Sub-PTSD > No-PTSD). When considering the number of clinically elevated scores, a linear relationship between PTSD severity and neurobehavioral functioning/quality of life was again observed in the MTBI sample (e.g., 3-or-more elevated scores: Full-PTSD = 92.1 %, Sub-PTSD = 61.9 %, No-PTSD = 19.9 %).
Limitations included the use of a self-report measure to determine diagnostic status that may under/overcount or mischaracterize individuals.
PTSD symptoms, whether at the level of diagnosable PTSD, or falling short of that because of the intensity or characterization of symptoms, have a significant negative impact on one's quality of life following MTBI. Clinicians' treatment targets should focus on the symptoms that are most troubling for an individual and the individual's perception of quality of life, regardless of the diagnosis itself.
The purpose of this study was to extend previous research by examining the relationship between lifetime blast exposure and neurobehavioral functioning after mild TBI (MTBI) by (a) using a ...comprehensive measure of lifetime blast exposure, and (b) controlling for the influence of post-traumatic stress disorder (PTSD). Participants were 103 United States service members and veterans (SMVs) with a medically documented diagnosis of MTBI, recruited from three military treatment facilities (74.8%) and community-based recruitment initiatives (25.2%, e.g., social media, flyers). Participants completed a battery of neurobehavioral measures 12 or more months post-injury (Neurobehavioral Symptom Inventory, PTSD-Checklist PCLC, TBI-Quality of Life), including the Blast Exposure Threshold Survey (BETS). The sample was classified into two lifetime blast exposure (LBE) groups: High (
= 57) and Low (
= 46) LBE. In addition, the sample was classified into four LBE/PTSD subgroups: High PTSD/High LBE (n = 38); High PTSD/Low LBE (
= 19); Low PTSD/High LBE (
= 19); and Low PTSD/Low LBE (
= 27). The High LBE group had consistently worse scores on all neurobehavioral measures compared with the Low LBE group. When controlling for the influence of PTSD (using ANCOVA), however, only a handful of group differences remained. When comparing measures across the four LBE/PTSD subgroups, in the absence of clinically meaningful PTSD symptoms (i.e., Low PTSD), participants with High LBE had worse scores on the majority of neurobehavioral measures (e.g., post-concussion symptoms, sleep, fatigue). When examining the total number of clinically elevated measures, the High LBE subgroup consistently had a greater number of clinically elevated scores compared with the Low LBE subgroup for the majority of comparisons (i.e., four to 15 or more elevated symptoms). In contrast, in the presence of clinically meaningful PTSD symptoms (i.e., High PTSD), there were no differences between High versus Low LBE subgroups for all measures. When examining the total number of clinically elevated measures, however, there were meaningful differences between High versus Low LBE subgroups for those comparisons that included a high number of clinically elevated scores (i.e., six to 10 or more), but not for a low number of clinically elevated scores (i.e., one to five or more). High LBE, as quantified using a more comprehensive measure than utilized in past research (i.e., BETS), was associated with worse overall neurobehavioral functioning after MTBI. This study extends existing literature showing that lifetime blast exposure, that is largely subconcussive, may negatively impact warfighter brain health and readiness beyond diagnosable brain injury.
The Department of Defense (DOD) has recently prioritized the investigation of the acute and chronic adverse brain health and performance effects of low-level blast (LLB) generated by the use of ...weapons systems. While acute exposure can be quantified by sensor technology, career exposure has no widely accepted and validated measure for characterization. Currently, distinct research groups are developing and validating four promising measures to estimate career blast exposure history: the Salisbury Blast Interview, Blast Exposure Threshold Survey, Blast Ordnance and Occupational Exposure Measure, and the Blast Frequency and Symptom Severity. Each measure offers an assessment of blast history that is uniquely beneficial to addressing specific research questions. However, use of divergent strategies is not efficient to accelerate the field's understanding of the impact of career exposure and Service-connected health outcomes. As a DOD-wide solution, collaboration across these groups is required to develop a tool(s) that can be standardized across research studies and, ultimately, pared down to be implemented in clinical settings. Here, we overview the current four measures and provide a perspective on the way forward for optimization and/or combination in support of this solution.
