Characterizing Extreme Phenotypes for Perceived Improvement From Treatment in Persons With Chronic Pain Following Traumatic Brain Injury: A NIDILRR and VA TBI Model Systems Collaborative Project.

OBJECTIVE: To define and characterize extreme phenotypes based on perceived improvement in pain for persons with chronic pain following traumatic brain injury (TBI). SETTING: Eighteen Traumatic Brain Injury Model System (TBIMS) Centers. PARTICIPANTS: A total of 1762 TBIMS participants 1 to 30 years post-injury reporting chronic pain at their most recent follow-up interview. PRIMARY MEASURES: The Patient's Global Impression of Change (PGIC) related to pain treatment. Sociodemographic, injury, functional outcome, pain, and pain treatment characteristics. RESULTS: Participants were mostly male (73%), White (75%), middle-aged (mean 46 years), injured in motor vehicle accidents (53%), or falls (20%). Extreme phenotypes were created for an extreme improvement phenotype ( n = 512, 29.8%) defined as "moderately better" or above on the PGIC and an extreme no-change group ( n = 290, 16.9%) defined as no change or worse. Least absolute shrinkage and selection operator (LASSO) regression combined with logistic regression identified multivariable predictors of improvement versus no-change extreme phenotypes. Higher odds of extreme improvement phenotype were significantly associated with being female (odds ratio [OR] = 1.85), married versus single (OR = 2.02), better motor function (OR = 1.03), lower pain intensity (OR = 0.78), and less frequent pain, especially chest pain (OR = 0.36). Several pain treatments were associated with higher odds of being in the extreme improvement versus no-change phenotypes including pain medication (OR = 1.85), physical therapy (OR = 1.51), yoga (OR = 1.61), home exercise program (OR = 1.07), and massage (OR = 1.69). CONCLUSION: Investigation of extreme phenotypes based on perceived improvement with pain treatment highlights the ability to identify characteristics of individuals based on pain treatment responsiveness. A better understanding of the biopsychosocial characteristics of those who respond and do not respond to pain treatments received may help inform better surveillance, monitoring, and treatment. With further research, the identification of risk factors (such as pain intensity and frequency) for treatment response/nonresponse may provide indicators to prompt changes in care for individuals with chronic pain after TBI.

Can mild traumatic brain injury alter cognition chronically? A LIMBIC-CENC multicenter study.

OBJECTIVE: While outcome from mild traumatic brain injury (mTBI) is generally favorable, concern remains over potential negative long-term effects, including impaired cognition. This study examined the link between cognitive performance and remote mTBIs within the Long-term Impact of Military-relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium (LIMBIC-CENC) multicenter, observational study of Veterans and service members (SMs) with combat exposure. METHOD: Baseline data of the participants passing all cognitive performance validity tests (n = 1,310) were used to conduct a cross-sectional analysis. Using multivariable regression models that adjusted for covariates, including age and estimated preexposure intellectual function, positive mTBI history groups, 1-2 lifetime mTBIs (nonrepetitive, n = 614), and 3 + lifetime mTBIs (repetitive; n = 440) were compared to TBI negative controls (n = 256) on each of the seven cognitive domains computed by averaging Z scores of prespecified component tests. Significance levels were adjusted for multiple comparisons. RESULTS: Neither of the mTBI positive groups differed from the mTBI negative control group on any of the cognitive domains in multivariable analyses. Findings were also consistently negative across sensitivity analyses (e.g., mTBIs as a continuous variable, number of blast-related mTBIs, or years since the first and last mTBI). CONCLUSIONS: Our findings demonstrate that the average veteran or SM who experienced one or more mTBIs does not have postacute objective cognitive deficits due to mTBIs alone. A holistic health care approach including comorbidity assessment is indicated for patients reporting chronic cognitive difficulties after mTBI(s), and strategies for addressing misattribution may be beneficial. Future study is recommended with longitudinal designs to assess within-subjects decline from potential neurodegeneration. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Associations Among PTSD and Postconcussive Symptoms in the Long-Term Impact of Military-Relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium Prospective, Longitudinal Study Cohort.

OBJECTIVE: To describe rates of mild traumatic brain injury (mTBI) with and without concurrent posttraumatic stress disorder a sample of former and current military personnel, and to compare the factor structure of the Neurobehavioral Symptom Inventory (NSI) based on whether participants sustained mTBI with and without a positive posttraumatic stress disorder (PTSD) screen. SETTING: Participants recruited and tested at 7 Veterans Affairs (VA) sites and 1 military training facility as part of a national, longitudinal study of mental health, physical, and cognitive outcomes among veterans and service members. Participants: Total of 1540 former and current military personnel with a history of combat exposure. DESIGN: Cross-sectional analysis of observational data, including confirmatory factor analysis. Main Measures: NSI and PTSD Checklist for DSM-5 (PCL-5). RESULTS: Most participants (81.5%) had a history of mTBI and almost half of these screened positive for PTSD (40.5%); only 23.9% of participants without a history of mTBI screened positive for PTSD. Participants with a history of mTBI reported higher elevations of NSI and PCL-5 symptoms compared with those without a history of mTBI. Confirmatory factor analyses of the NSI demonstrated good model fit using a 4-factor structure (somatosensory, affective, cognitive, and vestibular symptoms) among groups of participants both with and without a history of mTBI. CONCLUSION: Symptoms of mTBI and PTSD are strongly associated with each other among veterans and service members with a history of combat exposure. The 4-factor NSI structure is supported among participants with and without a history of mTBI. These findings suggest the potential benefit of a holistic approach to evaluation and treatment of veterans and service members with concurrent and elevated postconcussive and posttraumatic stress symptoms.

Hyperbaric oxygen for blast-related postconcussion syndrome: three-month outcomes.

OBJECTIVE: 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. METHODS: This randomized, double-blind, sham-controlled study was conducted at the Naval Air Station in Pensacola, Florida on 61 male Marines with a history of mTBI and PCS. Intervention consisted of 40 once daily 60-minute hyperbaric chamber compressions at 2.0 atmospheres absolute (ATA) at 1 of 3 randomly preassigned oxygen fractions, resulting in respective blinded groups with an oxygen-breathing exposure equivalent to (1) surface air (sham), (2) 100% oxygen at 1.5ATA, or (3) 100% oxygen at 2.0ATA. The main outcome measure was the Rivermead Post-Concussion Questionnaire-16 (RPQ-16) collected before compressions and at 2 later points. RESULTS: The interaction of time by intervention group was not significant for improvement on the RPQ-16. Nor was there evidence of efficacy on the RPQ-16 for any subgroup. No significant time by intervention interaction was found for any functional, cognitive, or psychomotor secondary outcome measure at an unadjusted 0.05 significance level. INTERPRETATION: Using a randomized control trial design and analysis including a sham, results showed no evidence of efficacy by 3 months post-compression to treat the symptomatic, cognitive, or behavioral sequelae of PCS after combat-related mTBI.

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.