Prevalence of Lifetime History of Traumatic Brain Injury among Older Male Veterans Compared with Civilians: A Nationally Representative Study

Traumatic Brain Injury in US Veterans: Prevalence and Associations With Physical, Mental, and Cognitive Health

OBJECTIVE

To examine the prevalence of traumatic brain injury (TBI) in the US veteran population, and physical, mental, and cognitive health conditions associated with TBI.

DESIGN

Retrospective cohort study.

SETTING

A nationally representative sample of US military veterans surveyed in 2019-2020.

PARTICIPANTS

Veterans with probable TBI (n=943; M=58.8 years, SD=16.4; 75.9% non-Hispanic White) and without probable TBI (n=3,033; M=63.3 years, SD=15.3; 78.6% non-Hispanic White) were categorized based on a 2-item modified Veterans Health Administration TBI screen or self-reported health professional diagnoses of concussion/TBI.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE(S)

Self-reported health professional-diagnosed physical and cognitive health conditions, disability with basic and instrumental activities of daily living (ADLs), positive screens for posttraumatic stress disorder (PTSD), major depressive disorder, anxiety disorder, alcohol use disorder, or drug use disorder, and current suicidal ideation or prior suicide attempts.

RESULTS

Among the full sample, 24.5% (95% confidence interval: 22.7, 26.3) had probable TBI. In adjusted analyses, probable TBI was independently associated with greater odds of rheumatoid arthritis (odds ratio [OR]=2.06), chronic pain (OR=1.87), kidney disease (OR=1.81), pulmonary disease (OR=1.74), arthritis (OR=1.65), migraine (OR=1.59), sleep disorders (OR=1.57), and osteoporosis or osteopenia (OR=1.51). Veterans with probable TBI also had higher odds of mild cognitive impairment (OR=4.53) and disability with ADLs (OR=2.18) and instrumental ADLs (OR=1.98), although ADL disability was explained by other physical health conditions. Probable TBI was associated with higher odds of probable current anxiety disorder (OR=2.82), major depressive disorder (OR=2.17), suicidal ideation (OR=1.78), PTSD (OR=1.72), drug use disorder (OR=1.54), and alcohol use disorder (OR=1.47).

CONCLUSIONS

Nearly 1-in-4 US veterans screen positive for probable TBI, which was associated with several physical and mental health conditions that adversely affect health and functioning. Results underscore the importance of multidisciplinary interventions that concurrently target the unique physical, mental, cognitive, and functional health needs of this population.

Chronic Pain Treatment Utilization in Rural Versus Urban/Suburban Inhabitants Following Traumatic Brain Injury

OBJECTIVE

To determine whether there are differences in healthcare utilization for chronic pain based on location (rural vs urban/suburban) or healthcare system (civilians vs Military Service Members and Veterans [SMVs]) after moderate-severe TBI.

SETTING

Eighteen Traumatic Brain Injury Model Systems (TBIMS) Centers.

PARTICIPANTS

A total of 1,741 TBIMS participants 1 to 30 years post-injury reporting chronic pain at their most recent follow-up interview.

PRIMARY MEASURES

Sociodemographic, injury, function outcome, pain, and pain treatment characteristics.

RESULTS

Participants were mostly male (72.9%), White (75.2%), civilian (76.9%), 46 years old on average, and had greater than high school education (59.9%). 32% of participants resided in rural areas and 67% in urban/suburban areas. No significant difference in healthcare utilization for chronic pain was observed between individuals living in rural versus urban/suburban locations after adjustment for relevant covariates. However, rural SMVs had odds ratios >3 for each major treatment category including medical services (OR = 3.56), exercise therapies (OR = 5.23), psychological services (OR = 4.43), complementary and alternative therapies (OR = 3.23), and pain rehabilitation program (OR = 4.16) compared to rural civilians. This same pattern of findings was seen SMVs in urban/suburban settings as well. Being married versus single, bachelor/graduate education versus high school or less, and employed versus unemployed all had odds ratios >1 for exercise therapies, psychological services, complementary and alternative therapies, and pain rehab program.

CONCLUSION

Contrary to initial hypotheses, there were no significant differences in healthcare utilization for chronic pain treatment comparing those in rural versus urban/suburban areas. However, differences were found between SMVs and civilians across both rural and urban/suburban locations suggesting that SMVs have more access to chronic pain treatment. The improved access to social and financial services afforded by VHA programs to SMVs may serve as a model for improving healthcare utilization in similar civilian populations.

Strabismus and Strabismus Surgery in the U.S. Veterans Health Administration: Foundational Analyses of Electronic Health Record Data from 2000 to 2022

Background/Objectives: Strabismus, or eye misalignment, has not been well-described in U.S. military Veterans. This study was undertaken to characterize Veterans with a strabismus diagnosis as well as those who underwent strabismus surgery. Methods: A retrospective analysis of electronic health records (EHR) from the Veterans Health Administration (VHA) was conducted using patient data from 2000 to 2022. VHA-enrolled Veterans ≥ 18 years with strabismus-related International Classification of Diseases (ICD) codes and/or Current Procedural Terminology (CPT) codes were identified. Total and demographic (age group, sex, race, and ethnicity) stratified prevalence and incidence rates were calculated, as well as sex-stratified residual lifetime risk. Results: A total of 321,639 patients had a strabismus diagnosis, with most (320,107) identified by ICD code (CPT code only = 1532). The peak prevalence was 2.29% in the 2022 VHA fiscal year (1 October 2021 to 30 September 2022) with a median annual age-adjusted incidence rate of 168.9/100 000 enrollees. Age-adjusted lifetime risk was 10.19% for males and 11.03% for females. Significant differences by age group, sex, race, and ethnicity were identified for strabismus prevalence (p < 0.001), strabismus diagnosis types (p < 0.001), and between patients with strabismus who either did or did not have surgery (sex p < 0.05, all others p < 0.001). Compared with other U.S. adult populations, VHA Veterans have similar or higher prevalence, annual incidence rates, and lifetime risk of a strabismus diagnosis, with demographic factors significantly affecting the rates and types of strabismus. Notably, despite lower prevalence and incidence than other racial groups, a higher percentage of African American patients with strabismus underwent surgery, contrasting with published Medicare data. Inconsistencies between ICD and CPT codes highlight potential miscoding and/or missing codes, with reliance on ICD code diagnoses potentially underestimating strabismus prevalence. Conclusions: Further characterization of factors affecting strabismus risk among these patients may help improve strabismus diagnosis and management for many US Veterans. This foundational study serves as a platform for detailed predictive analyses in determining risk outcomes for individuals. This includes better identification of at-risk individuals, informing effective resource allocation for treatment.

The diagnostic and prognostic utility of oxidative stress circulatory biomarkers in traumatic brain injury patients: a systematic review

OBJECTIVE

The objective of this review is to qualitatively appraise the available literature to evaluate the efficacy of circulatory systemic oxidative stress markers (OSMx) in determining the diagnosis and outcome of TBI.

METHODS

A systematic review was conducted of PubMed/Medline, Embase and Google Scholar databases per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) for studies which employed serum or plasma OSMx analysis for diagnostic or prognostic purposes in patients with TBI.

RESULTS

Eight studies were included. There were 654 patients across the eight studies, of which 518 (79.2%) patients had sustained a TBI. The heterogeneity between studies in terms of OSMxs analyzed ultimately made collective analysis inappropriate. Nevertheless, several studies highlighted the potential role of circulatory OSMx levels in determining the diagnosis (presence and severity) and prognosis (functional outcome and mortality) of TBI.

CONCLUSION

The care for patients with TBI remains a complex clinical challenge with a high morbidity and mortality profile. Evidenced by this review, circulatory OSMxs appear to have the potential to supplement current diagnostic measures, in addition to identifying new treatment strategies and monitoring recovery. Despite early promise, the evidence for such markers remains in its infancy and robust prospective studies are needed.

Psychiatric Disorders Are Common Among Older US Veterans Prior to Traumatic Brain Injury

OBJECTIVE

To estimate the impact of traumatic brain injury (TBI) on prevalence of posttraumatic stress disorder (PTSD), depression, and alcohol and substance use disorders.

SETTING

A random sample of Veteran's Health Administration data.

PARTICIPANTS

A total of 14 116 veterans aged ≥55 with incident late-life TBI between October 1, 1999, and September 31, 2021, were matched 1:3 on age and TBI date to 42 678 veterans without TBI.

DESIGN

Retrospective cohort study.

MAIN MEASURES

PTSD, depression, and alcohol and substance use disorders were identified using diagnostic codes. Participants were censored after the first diagnosis during the year before and the year after the TBI or matched date. Prevalence rates of PTSD, depression, alcohol, and substance use disorders were compared before and after incident TBI or matched date using Poisson regression.

RESULTS

Pre-TBI prevalence rates of disorders were higher among those with TBI relative to those without TBI. Pre-TBI PTSD prevalence rates (per 1000 person-years) were 126.3 (95% CI, 120.2-132.4) compared to 21.5 (95% CI, 20.1-22.9) in the non-TBI cohort. In adjusted models, TBI was not associated with an increase in the prevalence of any of the studied disorders.

CONCLUSIONS

Prevalence rates of depression, PTSD, and alcohol and substance use disorders were 5 to 10 times higher among older veterans before incident TBI. We did not observe an increase in the prevalence of these disorders after incident TBI. Older veterans with these disorders may be at increased risk for TBI.

Prevalence of Traumatic Brain Injury in the General Adult Population of the USA: A Meta-Analysis

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. It has been estimated that 64-74 million individuals experience TBI from all causes each year. Due to these variations in reporting TBI prevalence in the general population, we decided to perform a meta-analysis of published studies to better understand the prevalence of TBI in the general adult population of the USA which can help health decision-makers in determining general policies to reduce TBI cases and their costs and burden on the healthcare system.

METHODS

Our meta-analysis was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. The study protocol was registered with PROSPERO (CRD42024534598). A comprehensive literature search of PubMed from the National Library of Medicine and Google Scholar was performed from database inception to April 2024. Sixteen studies that evaluated the US general population met our inclusion criteria. A meta-analysis using a random-effects model was performed to estimate the prevalence of TBI in the general adult population of the USA.

RESULTS

The total sample consisted of 27,491 individuals, of whom 4,453 reported a lifetime history of TBI with loss of consciousness (LOC) (18.2%, 95% CI 14.4-22.7%). Some studies did not report relevant information based on gender, but based on available data, among males, 1,843 individuals out of 8,854 reported a lifetime history of TBI with LOC (20.8%). Among females, 1,363 individuals out of 11,943 reported a lifetime history of TBI with LOC (11.4%). The odds of sustaining TBI in males were higher than in females with moderate heterogeneity between studies (OR = 2.09, 95% CI 1.85-2.36, p < 0.01, I2 = 40%).

CONCLUSION

The prevalence of TBI in the US general population is 18.2%, making it a major public health concern. In addition, males were more than twice as likely as females to sustain TBI with LOC. Considering the irreparable long-term adverse effects of TBI on survivors, their families, and the healthcare system, prevention strategies can facilitate substantial reductions in TBI-related permanent disabilities and medical care costs.

Why Do Veterans Not Respond as Well as Civilians to Trauma-Focused Therapies for PTSD?

ABSTRACT

This column first reviews evidence that veterans have poorer response to trauma-focused therapies for PTSD compared to civilians. We then consider several explanations for this trend, starting with gender as a possible confounding variable. We also examine other hypotheses, including the effects of the military acculturation process, the unique influences of military traumas, such as combat and military sexual traumas, and the roles of traumatic brain injuries (TBIs) and moral injury. Future research, we conclude, must determine whether gender explains the differences in trauma-focused therapy response. If so, then the underlying reasons must be further explored. If not, then we must determine the unique characteristics of the veteran population that make it more resistant to treatment. Mining these elements will help us adapt our trauma-focused therapies to better help this population and close the response-rate gap.

Incidence of Traumatic Brain Injury in a Longitudinal Cohort of Older Adults

Importance

Traumatic brain injury (TBI) occurs at the highest rate in older adulthood and increases risk for cognitive impairment and dementia.

Objectives

To update existing TBI surveillance data to capture nonhospital settings and to explore how social determinants of health (SDOH) are associated with TBI incidence among older adults.

Design, Setting, and Participants

This nationally representative longitudinal cohort study assessed participants for 18 years, from August 2000 through December 2018, using data from the Health and Retirement Study (HRS) and linked Medicare claims dates. Analyses were completed August 9 through December 12, 2022. Participants were 65 years of age or older in the HRS with survey data linked to Medicare without a TBI prior to HRS enrollment. They were community dwelling at enrollment but were retained in HRS if they were later institutionalized.

Exposures

Baseline demographic, cognitive, medical, and SDOH information from HRS.

Main Outcomes and Measures

Incident TBI was defined using inpatient and outpatient International Classification of Diseases, Ninth or Tenth Revision, diagnosis codes received the same day or within 1 day as the emergency department (ED) visit code and the computed tomography (CT) or magnetic resonance imaging (MRI) code, after baseline HRS interview. A cohort with TBI codes but no ED visit or CT or MRI scan was derived to capture diagnoses in nonhospital settings. Descriptive statistics and bivariate associations of TBI with demographic and SDOH characteristics used sample weights. Fine-Gray regression models estimated associations between covariates and TBI, with death as a competing risk. Imputation considering outcome and complex survey design was performed by race and ethnicity, sex, education level, and Area Deprivation Index percentiles 1, 50, and 100. Other exposure variables were fixed at their weighted means.

Results

Among 9239 eligible respondents, 5258 (57.7%) were female and 1210 (9.1%) were Black, 574 (4.7%) were Hispanic, and 7297 (84.4%) were White. Mean (SD) baseline age was 75.2 (8.0) years. During follow-up (18 years), 797 (8.9%) of respondents received an incident TBI diagnosis with an ED visit and a CT code within 1 day, 964 (10.2%) received an incident TBI diagnosis and an ED code, and 1148 (12.9%) received a TBI code with or without an ED visit and CT scan code. Compared with respondents without incident TBI, respondents with TBI were more likely to be female (absolute difference, 7.0 [95% CI, 3.3-10.8]; P < .001) and White (absolute difference, 5.1 [95% CI, 2.8-7.4]; P < .001), have normal cognition (vs cognitive impairment or dementia; absolute difference, 6.1 [95% CI, 2.8-9.3]; P = .001), higher education (absolute difference, 3.8 [95% CI, 0.9-6.7]; P < .001), and wealth (absolute difference, 6.5 [95% CI, 2.3-10.7]; P = .01), and be without baseline lung disease (absolute difference, 5.1 [95% CI, 3.0-7.2]; P < .001) or functional impairment (absolute difference, 3.3 [95% CI, 0.4-6.1]; P = .03). In adjusted multivariate models, lower education (subdistribution hazard ratio [SHR], 0.73 [95% CI, 0.57-0.94]; P = .01), Black race (SHR, 0.61 [95% CI, 0.46-0.80]; P < .001), area deprivation index national rank (SHR 1.00 [95% CI 0.99-1.00]; P = .009), and male sex (SHR, 0.73 [95% CI, 0.56-0.94]; P = .02) were associated with membership in the group without TBI. Sensitivity analyses using a broader definition of TBI yielded similar results.

Conclusions and Relevance

In this longitudinal cohort study of older adults, almost 13% experienced incident TBI during the 18-year study period. For older adults who seek care for TBI, race and ethnicity, sex, and SDOH factors may be associated with incidence of TBI, seeking medical attention for TBI in older adulthood, or both.

Long Noncoding RNA VLDLR-AS1 Levels in Serum Correlate with Combat-Related Chronic Mild Traumatic Brain Injury and Depression Symptoms in US Veterans

More than 75% of traumatic brain injuries (TBIs) are mild (mTBI) and military service members often experience repeated combat-related mTBI. The chronic comorbidities concomitant with repetitive mTBI (rmTBI) include depression, post-traumatic stress disorder or neurological dysfunction. This study sought to determine a long noncoding RNA (lncRNA) expression signature in serum samples that correlated with rmTBI years after the incidences. Serum samples were obtained from Long-Term Impact of Military-Relevant Brain-Injury Consortium Chronic Effects of Neurotrauma Consortium (LIMBIC CENC) repository, from participants unexposed to TBI or who had rmTBI. Four lncRNAs were identified as consistently present in all samples, as detected via droplet digital PCR and packaged in exosomes enriched for CNS origin. The results, using qPCR, demonstrated that the lncRNA VLDLR-AS1 levels were significantly lower among individuals with rmTBI compared to those with no lifetime TBI. ROC analysis determined an AUC of 0.74 (95% CI: 0.6124 to 0.8741; p = 0.0012). The optimal cutoff for VLDLR-AS1 was ≤153.8 ng. A secondary analysis of clinical data from LIMBIC CENC was conducted to evaluate the psychological symptom burden, and the results show that lncRNAs VLDLR-AS1 and MALAT1 are correlated with symptoms of depression. In conclusion, lncRNA VLDLR-AS1 may serve as a blood biomarker for identifying chronic rmTBI and depression in patients.

Differences in Risk of Alzheimer's Disease Following Later-Life Traumatic Brain Injury in Veteran and Civilian Populations

OBJECTIVE

To directly compare the effect of incident age 68+ traumatic brain injury (TBI) on the risk of diagnosis of clinical Alzheimer's disease (AD) in the general population of older adults, and between male veterans and nonveterans; to assess how this effect changes with time since TBI.

SETTING AND PARTICIPANTS

Community-dwelling traditional Medicare beneficiaries 68 years or older from the Health and Retirement Study (HRS).

DESIGN

Fine-Gray models combined with inverse-probability weighting were used to identify associations between incident TBI, post-TBI duration, and TBI treatment intensity, with a diagnosis of clinical AD dementia. The study included 16 829 older adults followed over the 1991-2015 period. For analyses of veteran-specific risks, 4281 veteran males and 3093 nonveteran males were identified. Analysis of veteran females was unfeasible due to the age structure of the population. Information on occurrence(s) of TBI, and onset of AD and risk-related comorbidities was constructed from individual-level HRS-linked Medicare claim records while demographic and socioeconomic risk factors were based on the survey data.

RESULTS

Later-life TBI was strongly associated with increased clinical AD risk in the full sample (pseudo-hazard ratio [HR]: 3.22; 95% confidence interval [CI]: 2.57-4.05) and in veteran/nonveteran males (HR: 5.31; CI: 3.42-7.94), especially those requiring high-intensity/duration care (HR: 1.58; CI: 1.29-1.91). Effect magnitude decreased with time following TBI (HR: 0.72: CI: 0.68-0.80).

CONCLUSION

Later-life TBI was strongly associated with increased AD risk, especially in those requiring high-intensity/duration care. Effect magnitude decreased with time following TBI. Univariate analysis showed no differences in AD risk between veterans and nonveterans, while the protective effect associated with veteran status in Fine-Gray models was largely due to differences in demographics, socioeconomics, and morbidity. Future longitudinal studies incorporating diagnostic procedures and documentation quantifying lifetime TBI events are necessary to uncover pathophysiological mediating and/or moderating mechanisms between TBI and AD.

Associations Between Sociodemographic, Mental Health, and Mild Traumatic Brain Injury Characteristics With Lifetime History of Criminal Justice Involvement in Combat Veterans and Service Members

INTRODUCTION

Veterans and service members (V/SM) may have more risk factors for arrest and felony incarceration (e.g., posttraumatic stress disorder and at-risk substance use) but also more protective factors (e.g., access to health care) to mitigate behaviors that may lead to arrest. As such, understanding which factors are associated with criminal justice involvement among V/SM could inform prevention and treatment efforts. The current study examined relationships between lifetime history of arrests and felony incarceration and sociodemographic, psychological, and brain injury characteristics factors among combat V/SM.

MATERIALS AND METHODS

The current study was a secondary data analysis from the Chronic Effects of Neurotrauma Consortium multicenter cohort study, approved by local institutional review boards at each study site. Participants were V/SM (N = 1,540) with combat exposure (19% active duty at time of enrollment) who were recruited from eight Department of Veterans Affairs and DoD medical centers and completed a baseline assessment. Participants were predominantly male (87%) and white (72%), with a mean age of 40 years (SD = 9.7). Most (81%) reported a history of at least one mild traumatic brain injury, with one-third of those experiencing three or more mild traumatic brain injuries (33%). Participants completed a self-report measure of lifetime arrest and felony incarceration history, a structured interview for all potential concussive events, the post-traumatic stress disorder checklist for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), and the Alcohol Use Disorders Identification Test-Consumption. Three groups were compared on self-reported level of lifetime history of criminal justice system involvement: (1) no history of arrest or incarceration (65%); (2) history of arrest but no felony incarceration (32%); and (3) history of felony incarceration (3%).

RESULTS

Ordinal regression analyses revealed that hazardous alcohol consumption (β = .44, P < .001; odds ratio = 1.56) was positively associated with increased criminal justice involvement after adjusting for all other variables. Being married or partnered (β = -.44, P < .001; odds ratio = 0.64) was negatively associated with decreased criminal justice involvement.

CONCLUSIONS

The rate of lifetime arrest (35%) in this V/SM sample was consistent with rates of arrests in the U.S. general population. One modifiable characteristic associated with lifetime arrest and felony incarceration was hazardous alcohol consumption. Alcohol use should be a top treatment target for V/SM at risk for arrest and those with history of criminal justice involvement.

Traumatic Brain Injury and Long-Term Risk of Stroke Among US Military Veterans

BACKGROUND

Traumatic brain injury (TBI) is associated with significant morbidity, but the association of TBI with long-term stroke risk in diverse populations remains less clear. Our objective was to examine the long-term associations of TBI with stroke and to investigate potential differences by age, sex, race and ethnicity, and time since TBI diagnosis.

METHODS

Retrospective cohort study of US military veterans aged 18+ years receiving healthcare in the Veterans Health Administration system between October 1, 2002 and September 30, 2019. Veterans with TBI were matched 1:1 to veterans without TBI on age, sex, race and ethnicity, and index date, yielding 306 796 veterans with TBI and 306 796 veterans without TBI included in the study. In primary analyses, Fine-Gray proportional hazards models adjusted for sociodemographics and medical/psychiatric comorbidities were used to estimate the association between TBI and stroke risk, accounting for the competing risk of mortality.

RESULTS

Participants were a mean age of 50 years, 9% were female, and 25% were of non-White race and ethnicity. Overall, 4.7% of veterans developed a stroke over a median follow-up of 5.2 years. Veterans with TBI had 1.69 times (95% CI, 1.64-1.73) increased risk of any stroke (ischemic or hemorrhagic) compared to veterans without TBI. This increased risk was highest in the first-year post-TBI diagnosis (hazard ratio [HR], 2.16 [95% CI, 2.03-2.29]) but remained elevated for 10+ years. Similar patterns were observed for secondary outcomes, with associations of TBI with hemorrhagic stroke (HR, 3.92 [95% CI, 3.59-4.29]) being stronger than with ischemic stroke (HR, 1.56 [95% CI, 1.52-1.61]). Veterans with both mild (HR, 1.47 [95% CI, 1.43-1.52]) and moderate/severe/penetrating injury (HR, 2.02 [95% CI, 1.96-2.09]) had increased risk of stroke compared to veterans without TBI. Associations of TBI with stroke were stronger among older compared to younger individuals (P interaction-by-age<0.001) and were weaker among Black veterans compared to other race and ethnicities (P interaction-by-race<0.001).

CONCLUSIONS

Veterans with prior TBI are at increased long-term risk for stroke, suggesting they may be an important population to target for primary stroke prevention measures.