Assessing for mild TBI among Iraq and Afghanistan veterans: Outcomes of injury severity and neurological factors.

OBJECTIVE: To investigate injury severity markers and neurological symptoms associated with clinician-confirmed mild traumatic brain injury (TBI) among Iraq and Afghanistan veterans. SETTING: Department of Veterans Affairs (VA) medical centre and five affiliated community-based outpatient clinics. PARTICIPANTS: Three hundred and fifty Iraq and Afghanistan veterans with positive initial VA TBI screens between 1 April 2007 and 1 June 2010 and clinician-confirmed TBI status by 1 December 2010. METHODS: Retrospective-cohort study of medical record data. Main measures included clinician-confirmed TBI status, injury severity markers (e.g. loss of consciousness (LOC), post-traumatic amnesia (PTA) or confusion/disorientation) and neurological symptoms. RESULTS: Among veterans who screened positive on the initial VA TBI and then received a clinician evaluation, 60% were confirmed to have a TBI diagnosis. Veterans reporting at least one LOC, confusion or PTA were almost 18-times more likely to receive a confirmed TBI diagnosis. Odds of clinician-confirmed TBI were 2.5-3-times greater among those who endorsed dizziness, poor coordination, headaches, nausea, vision problems and/or irritability, compared to those not endorsing these symptoms. Nausea had greatest utility for confirming a TBI. CONCLUSIONS: Identification of neurologic symptoms that most contribute to a clinician-confirmed diagnosis of TBI has potential for streamlining detection of TBI and symptoms needed for treatment.

Early Cognitively Based Functional Limitations Predict Loss of Independence in Instrumental Activities of Daily Living in Older Adults.

Older adults with early forms of neurodegenerative disease are at risk for functional disability, which is often defined by the loss of independence in instrumental activities of daily living (IADLs). The current study investigated the influence of mild changes in everyday functional abilities (referred to as functional limitations) on risk for development of incident functional disability. A total of 407 participants, who were considered cognitively normal or diagnosed with mild cognitive impairment (MCI) at baseline, were followed longitudinally over an average 4.1 years (range=0.8-9.2 years). Informant-based ratings from the Everyday Cognition (ECog; Farias et al., 2008) and the Instrumental Activities of Daily Living (Lawton & Brody, 1969) scales assessed the degree of functional limitations and incident IADL disability, respectively. Cox proportional hazards models revealed that more severe functional limitations (as measured by the Total ECog score) at baseline were associated with approximately a four-fold increased risk of developing IADL disability a few years later. Among the ECog domains, functional limitations in Everyday Planning, Everyday Memory, and Everyday Visuospatial domains were associated with the greatest risk of incident functional disability. These results remained robust even after controlling for participants' neuropsychological functioning on tests of executive functions and episodic memory. Current findings indicate that early functional limitations have prognostic value in identifying older adults at risk for developing functional disability. Findings highlight the importance of developing interventions to support everyday abilities related to memory, executive function, and visuospatial skills in an effort to delay loss of independence in IADLs.

Self-rated and informant-rated everyday function in comparison to objective markers of Alzheimer's disease.

It is recognized that individuals with mild cognitive impairment (MCI) already demonstrate difficulty in aspects of daily functioning, which predicts disease progression. This study examined the relationship between self- versus informant-report of functional ability, and how those reports relate to objective disease measures across the disease spectrum (i.e. cognitively normal, MCI, Alzheimer's disease). A total of 1080 subjects with self- and/or informant-rated Everyday Cognition questionnaires were included. Objective measures included cognitive functioning, structural brain atrophy, cerebrospinal fluid abnormalities, and a marker of amyloid deposition using positron emission tomography with [18F]AV45 (florbetapir). Overall, informant-report was consistently more associated with objective markers of disease than self-report although self-reported functional status may still have some utility in early disease.

The impact of head injury mechanism on mental health symptoms in veterans: do number and type of exposures matter?

This study examined the association between screening results for mental health problems and the number and type of head injuries in 1,082 Iraq and Afghanistan War veterans who received population-based screening for traumatic brain injury at a Veterans Administration health care facility. Nearly one third of all veterans reported multiple types of head injuries (median = 1 among those with any head injury, range = 1-6 types of head injury). Veterans reporting multiple head injury mechanisms had 6 times the odds of screening positive for posttraumatic stress disorder (PTSD), adjusted odds ratio (OR) = 6.15, 95% confidence interval (CI) [4.4, 8.7], p < .001, over 4 times the odds of screening positive for depression, adjusted OR = 4.09, 95% CI [2.8, 5.9], p < .001, and about twice the odds of screening positive for alcohol misuse, adjusted OR = 1.64, 95% CI [1.19, 2.3], p = .003, compared to those without head injuries. Veterans reporting a blast plus another head injury mechanism had higher odds of screening positive for all mental health outcomes than any other group (e.g., compared to no head injury group): PTSD, adjusted OR = 6.52, 95% CI [4.6, 9.3], p < .001; depression, adjusted OR = 4.42, 95% CI [3.0, 6.4], p < .001; alcohol misuse, adjusted OR =1.59, 95% CI [1.14, 2.2], p = .006. Given their association with a variety of mental health outcomes, number and type of head injury mechanism should be considered as part of any postdeployment evaluation.

Factors associated with completing comprehensive traumatic brain injury evaluation.

This study examined factors associated with Iraq and Afghanistan Veterans following up with the Department of Veterans Affairs (VA) comprehensive traumatic brain injury (TBI) evaluation after a positive first-level VA TBI screen. Participants included 465 Iraq and Afghanistan Veterans at one VA Medical Center and its five affiliated community-based outpatient clinics, with a positive initial TBI screen between April 1, 2007 and June 1, 2010. We found that 75% of Veterans completed the comprehensive TBI evaluation. Women were three times less likely to complete the comprehensive TBI evaluation than men, and those who endorsed post-traumatic stress disorder avoidance symptoms were nearly two times less likely to complete the comprehensive TBI evaluation. In contrast, headaches, Hispanic ethnicity, and the season of the initial TBI screen (summer vs. winter) were positively associated with completing a comprehensive TBI evaluation. A substantial minority of Veterans who screen positive on the VA initial TBI screen fail to present for the comprehensive TBI evaluation. Addressing specific gender-related issues, avoidance, and the timing of referrals in the context of VA polytrauma programs may increase the likelihood that Veterans receive further assessment, education, and early intervention for TBI or other mental health problems to prevent chronic postdeployment disability.

Service utilization among Iraq and Afghanistan veterans screening positive for traumatic brain injury.

We compared mental health outpatient, primary care, and emergency care service utilization among veterans screening TBI positive (S-TBI⁺) versus those screening TBI negative (S-TBI⁻) and describe associations between TBI-related symptoms and health service utilization. Our study population consisted of 1746 Iraq and Afghanistan veterans in VA care screened for TBI between April 1, 2007 and June 1, 2010. Rates of mental health outpatient, primary care, and emergency services utilization were greater for S-TBI(+) veterans, compared with S-TBI(-) veterans, even after adjusting for mental health screen results. Irritability on the initial TBI screen was associated with increased mental health outpatient utilization rates [incidence rate ratio (IRR), 1.64; 95% confidence interval (CI), 1.18-2.3; p<0.01]. Reports of dizziness (IRR, 1.24; 95% CI, 1.02-1.51; p<0.05) and headaches (IRR, 1.41; 95% CI, 1.16-1.7; p<0.001) were associated with increased primary care utilization rates. Higher utilization rates among veterans who screened positive for TBI were not better explained by screening positive for comorbid mental health problems. Knowing that certain symptoms are more strongly associated with increased utilization in certain health service domains will help to better plan for the care of returning veterans who screen positive for TBI.

Relationship of screen-based symptoms for mild traumatic brain injury and mental health problems in Iraq and Afghanistan veterans: Distinct or overlapping symptoms?

This study used factor analytic techniques to differentiate distinct from overlapping screen-based symptoms of traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), and depression in Iraq and Afghanistan veterans. These symptoms were derived from screen results of 1,549 veterans undergoing Department of Veterans Affairs postdeployment screening between April 2007 and January 2010. Veterans with positive TBI screens were approximately twice as likely to also screen positive for depression and PTSD (adjusted relative risks = 1.9 and 2.1, respectively). Irritability was a shared symptom between TBI and PTSD, and emotional numbing was a shared symptom between PTSD and depression. Symptoms unique to TBI included dizziness, headaches, memory problems, and light sensitivity. Four separate constructs emerged: TBI, PTSD, depression, and a fourth construct consisting of hypervigilance and sleep problems. These findings illuminate areas of overlap between TBI and common postdeployment mental health problems. Discriminating symptoms of TBI from mental health problems may facilitate diagnosis, triage to specialty care, and targeted symptom management. The emergence of a fourth factor consisting of sleep problems and hypervigilance highlights the need to attend to specific symptoms in the postdeployment screening process.