Laura M. Franke

Hyperbaric oxygen for blast‐related postconcussion syndrome: Three‐month outcomes

Mild traumatic brain injury (mTBI) and postconcussion syndrome (PCS) are common among military combatants. Hyperbaric oxygen (HBO2) is a proposed treatment for these conditions, but it has not been rigorously studied. The objective of this study was to determine the effects of HBO2 by 3 months post compression at 2 commonly employed dosing levels to treat PCS; whether specific subgroups may have benefited; and if no overall effect was found, whether benefit is masked by other conditions.

Subjective Sleep Disturbance in Veterans Receiving Care in the Veterans Affairs Polytrauma System Following Blast-Related Mild Traumatic Brain Injury

OBJECTIVES This investigation sought to characterize prevalence and factors associated with subjective sleep disturbance (SSD) in a clinical sample of veterans with blast-related mild traumatic brain injury (mTBI). METHODS Adult veterans with history of blast-related mTBI were enrolled in a cross-sectional study. Data on demographics, injury, and current symptoms, including SSD, were obtained. Descriptive and univariate analyses investigated prevalence of SSD and associated factors. RESULTS Participants were 114 veterans with blast-related mTBI (96% male; mean age = 31 years, SD = 8; mean number of days since injury =1,044, SD = 538). 78% screened positive for post-traumatic stress disorder and 77% reported SSD. Loss of consciousness at time of injury, current nightmares, depression, headache, fatigue, and positive screen for post-traumatic stress disorder were significantly associated with SSD (p < 0.05). CONCLUSIONS SSD was pervasive in this clinical sample and was significantly associated with multiple modifiable emotional symptoms as well as headache and fatigue; this is consistent with previous literature including samples with history of nonblast-related mTBI. Future research incorporating objective measurement of SSD and associated symptoms is needed to inform evidence-based screening, assessment, and treatment efforts for veterans with history of mTBI.

Factor analysis of persistent postconcussive symptoms within a military sample with blast exposure

Objective:To determine the factor structure of persistent postconcussive syndrome symptoms in a blast-exposed military sample and validate factors against objective and symptom measures. Setting:Veterans Affairs medical center and military bases. Participants:One hundred eighty-one service members and veterans with at least 1 significant exposure to blast during deployment within the 2 years prior to study enrollment. Design:Confirmatory and exploratory factor analyses of the Rivermead Postconcussion Questionnaire. Main Measures:Rivermead Postconcussion Questionnaire, PTSD (posttraumatic stress disorder) Symptom Checklist–Civilian, Center for Epidemiological Studies Depression scale, Sensory Organization Test, Paced Auditory Serial Addition Test, California Verbal Learning Test, and Delis-Kaplan Executive Function System subtests. Results:The 3-factor structure of persistent postconcussive syndrome was not confirmed. A 4-factor structure was extracted, and factors were interpreted as reflecting emotional, cognitive, visual, and vestibular functions. All factors were associated with scores on psychological symptom inventories; visual and vestibular factors were also associated with balance performance. There was no significant association between the cognitive factor and neuropsychological performance or between a history of mild traumatic brain injury and factor scores. Conclusion:Persistent postconcussive symptoms observed months after blast exposure seem to be related to 4 distinct forms of distress, but not to mild traumatic brain injury per se, with vestibular and visual factors possibly related to injury of sensory organs by blast.

The Chronic Effects of Neurotrauma Consortium (CENC) multi-centre observational study: Description of study and characteristics of early participants

Abstract Primary objectives: To establish and comprehensively evaluate a large cohort of US veterans who served in recent military conflicts in order to better understand possible chronic and late-life effects of mild traumatic brain injury (mTBI), including those that may stem from neurodegeneration. Research design: Cross-sectional and prospective longitudinal. Methods and procedures: Inclusion criteria are prior combat exposure and deployment(s) in Operation Enduring Freedom, Operation Iraqi Freedom or one of their follow-on conflicts (collectively OEF/OIF). Effects of mTBI will be assessed by enrolling participants across the entire spectrum of mTBI, from entirely negative to many mTBIs. Longitudinal assessments consist of in-person comprehensive testing at least every 5 years, with interval annual telephonic testing. The primary outcome is the composite score on the NIH Toolbox neuropsychological test battery. Assessments also include structured interviews, questionnaires, traditional neuropsychological testing, motor, sensory and vestibular functions, neuroimaging, electrophysiology, genotypes and biomarkers. Main outcomes and results: The authors fully describe the study methods and measures and report demographic and exposure characteristics from the early portion of the cohort of OEF/OIF veterans. Conclusions: This centrepiece observational study of the Chronic Effects of Neurotrauma Consortium (CENC) is successfully launched and, within several years, should provide fertile data to begin investigating its aims.

Prevalence of mental health conditions after military blast exposure, their co-occurrence, and their relation to mild traumatic brain injury.

Abstract Primary objectives: To measure common psychiatric conditions after military deployment with blast exposure and test relationships to post-concussion syndrome (PCS) symptoms and mild traumatic brain injury (mTBI) history. Research design: Cross-sectional. Methods and procedures: Service members or Veterans (n = 107) within 2 years of blast exposure underwent structured interviews for mTBI, post-traumatic stress disorder (PTSD) and multiple mood and anxiety diagnoses. Main outcomes and results: MTBI history and active PTSD were both common, additionally 61% had at least one post-deployment mood or anxiety disorder episode. Psychiatric diagnoses had a high degree of comorbidity. Most dramatically, depression was 43-times (95% CI = 11–165) more likely if an individual had PTSD. PCS symptoms were greater in those with post-deployment PTSD or mood diagnosis. However, neither mTBI nor blast exposure history had an effect on the odds of having PTSD, mood or anxiety condition. Conclusions: These findings support that psychiatric conditions beyond PTSD are common after military combat deployment with blast exposure. They also highlight the non-specificity of post-concussion type symptoms. While some researchers have implicated mTBI history as a contributor to post-deployment mental health conditions, no clear association was found. This may partly be due to the more rigorous method of retrospective mTBI diagnosis determination.

Characterizing effects of mild traumatic brain injury and posttraumatic stress disorder on balance impairments in blast-exposed servicemembers and Veterans using computerized posturography

The high rate of blast exposures experienced by U.S. servicemembers (SMs) during the recent conflicts in Iraq and Afghanistan has resulted in frequent combat-related mild traumatic brain injuries (mTBIs). Dizziness and postural instability can persist after mTBI as a component of postconcussion syndrome, but also occur among the somatic complaints of posttraumatic stress disorder (PTSD). The goals of this study were to examine the use of computerized posturography (CPT) to objectively characterize chronic balance deficits after mTBI and to explore the utility of CPT in distinguishing between combat and blast-exposed participants with and without mTBI and PTSD. Data were analyzed from a subject pool of 166 combat-exposed SMs and Veterans who had a blast experience within the past 2 yr while deployed. Using nonparametric tests and measures of impairment, we found that balance was deficient in participants diagnosed with mTBI with posttraumatic amnesia (PTA) or PTSD versus those with neither and that deficits were amplified for participants with both diagnoses. In addition, unique deficiencies were found using CPT for individuals having isolated mTBI with PTA and isolated PTSD. Computerized balance assessment offers an objective technique to examine the physiologic effects and provide differentiation between participants with combat-associated mTBI and PTSD.

Randomized, Sham-Controlled, Feasibility Trial of Hyperbaric Oxygen for Service Members With Postconcussion Syndrome Cognitive and Psychomotor Outcomes 1 Week Postintervention

Background. Mild traumatic brain injury (mTBI) and residual postconcussion syndrome (PCS) are common among combatants of the recent military conflicts in Iraq and Afghanistan. Hyperbaric oxygen (HBO2) is a proposed treatment but has not been rigorously studied for this condition. Objectives. In a secondary analysis, examine for possible effects on psychomotor (balance and fine motor) and cognitive performance 1 week after an HBO2 intervention in service members with PCS after mTBI. Methods. A randomized, double-blind, sham control, feasibility trial comparing pretreatment and posttreatment was conducted in 60 male active-duty marines with combat-related mTBI and PCS persisting for 3 to 36 months. Participants were randomized to 1 of 3 preassigned oxygen fractions (10.5%, 75%, or 100%) at 2.0 atmospheres absolute (ATA), resulting in respective groups with an oxygen exposure equivalent to (1) breathing surface air (Sham Air), (2) 100% oxygen at 1.5 ATA (1.5 ATAO2), and (3) 100% oxygen at 2.0 ATA (2.0 ATAO2). Over a 10-week period, participants received 40 hyperbaric chamber sessions of 60 minutes each. Outcome measures, including computerized posturography (balance), grooved pegboard (fine motor speed/dexterity), and multiple neuropsychological tests of cognitive performance, were collected preintervention and 1-week postintervention. Results. Despite the multiple sensitive cognitive and psychomotor measures analyzed at an unadjusted 5% significance level, this study demonstrated no immediate postintervention beneficial effect of exposure to either 1.5 ATAO2 or 2.0 ATAO2 compared with the Sham Air intervention. Conclusions. These results do not support the use of HBO2 to treat cognitive, balance, or fine motor deficits associated with mTBI and PCS.

Insomnia symptoms and behavioural health symptoms in veterans 1 year after traumatic brain injury

Abstract Objective: Insomnia and behavioural health symptoms 1 year after traumatic brain injury (TBI) were examined in a clinical sample representative of veterans who received inpatient treatment for TBI-related issues within the Veterans Health Administration. Methods: This was a cross-sectional sub-study (n = 112) of the Polytrauma Rehabilitation Centres’ traumatic brain injury model system programme. Prevalence estimates of insomnia, depression, general anxiety, nightmares, headache and substance use, stratified by injury severity, were derived. Univariate logistic regression was used to examine unadjusted effects for each behavioural health problem and insomnia by injury severity. Results: Participants were primarily male, < 30 years old and high school educated. Twenty-nine per cent met study criteria for insomnia; those with mild TBI were significantly more likely to meet criteria (43%) than those with moderate/severe TBI (22%), χ2(1, n = 112) = 5.088, p ≤ 0.05. Univariable logistic regression analyses revealed depressive symptoms and general anxiety were significantly associated with insomnia symptoms after TBI of any severity. Headache and binge drinking were significantly inversely related to insomnia symptoms after moderate/severe TBI, but not MTBI. Conclusions: Veterans with history of TBI, of any severity, and current insomnia symptoms may be at increased risk for depression and anxiety 1 year after TBI.

Symptom Trajectories After Military Blast Exposure and the Influence of Mild Traumatic Brain Injury.

Background: Blast-related mild traumatic brain injury (blast mTBI) is a signature wound of recent US military conflicts in the Middle East, but the relatedness of postconcussive symptoms (PCS) to the blast mTBI is unclear, and longitudinal symptom data are sparse. Objectives: To characterize postdeployment symptom levels and trajectories and to determine relationship to blast mTBI. Methods: A total of 216 participants within 2 years of blast exposure during deployment underwent structured interviews or algorithmic questionnaires for blast mTBI. Detailed symptom inventories for PCS, pain, posttraumatic stress disorder, and depression were taken serially at enrollment, 6 months, and 12 months later. Repeated-measure analysis of variance models were built. Results: Up to 50% of participants had at least 1 high-grade blast mTBI (with posttraumatic amnesia), 31% had low-grade only, and 19% had neither. Within the entire cohort, all 4 composite symptom scores started high and stayed unchanged. Between blast mTBI groups, symptom scores differed at every time point with some evidence of convergence over time. The PCS groups, different by definition to start, diverged further over time with those initially more symptomatic becoming relatively more so. Conclusions: History of blast mTBI accompanied by posttraumatic amnesia is associated with greater nonspecific symptoms after deployment, and prognosis for improvement when symptoms are prominent is poor.

Distinction in EEG slow oscillations between chronic mild traumatic brain injury and PTSD

Spectral information from resting state EEG is altered in acute mild traumatic brain injury (mTBI) and in disorders of consciousness, but there is disagreement about whether mTBI can elicit long term changes in the spectral profile. Even when identified, any long-term changes attributed to TBI can be confounded by psychiatric comorbidities such as PTSD, particularly for combat-related mTBI where postdeployment distress is commonplace. To address this question, we measured spectral power during the resting state in a large sample of service members and Veterans varying in mTBI history and active PTSD diagnosis but matched for having had combat blast exposure. We found that PTSD was associated with decreases in low frequency power, especially in the right temporoparietal region, while conversely, blast-related mTBI was associated with increases in low frequency power, especially in prefrontal and right temporal areas. Results support the idea that long-term neurophysiological effects of mTBI share some features with states of reduced arousal and cognitive dysfunction, suggesting a role for EEG in tracking the trajectory of recovery and persisting vulnerabilities to injury. Additionally, results suggest that EEG power reflects distinct pathophysiologies for current PTSD and chronic mTBI.