John H. Poole

Program development and defining characteristics of returning military in a VA Polytrauma Network Site

The conflicts in Iraq and Afghanistan have resulted in a new generation of combat survivors with complex physical injuries and emotional trauma. This article reports the initial implementation of the Polytrauma Network Site (PNS) clinic, which is a key component of the Department of Veterans Affairs (VA) Polytrauma System of Care and serves military personnel returning from combat. The PNS clinic in Palo Alto, California, is described to demonstrate the VA healthcare systems evolving effort to meet the clinical needs of this population. We summarize the following features of this interdisciplinary program: (1) sequential assessment, from initial traumatic brain injury screening throughout our catchment area to evaluation by the PNS clinic team, and (2) clinical evaluation results for the first 62 clinic patients. In summary, this population shows a high prevalence of postconcussion symptoms, posttraumatic stress, poor cognitive performance, head and back pain, auditory and visual symptoms, and problems with dizziness or balance. An anonymous patient feedback survey, which we used to fine-tune the clinic process, reflected high satisfaction with this new program. We hope that the lessons learned at one site will enhance the identification and treatment of veterans with polytrauma across the country.

Predictive validity of driving-simulator assessments following traumatic brain injury: a preliminary study

Objective: To evaluate whether driving simulator and road test evaluations can predict long-term driving performance, we conducted a prospective study on 11 patients with moderate to severe traumatic brain injury. Sixteen healthy subjects were also tested to provide normative values on the simulator at baseline. Method: At their initial evaluation (time-1), subjects’ driving skills were measured during a 30-minute simulator trial using an automated 12-measure Simulator Performance Index (SPI), while a trained observer also rated their performance using a Driving Performance Inventory (DPI). In addition, patients were evaluated on the road by a certified driving evaluator. Ten months later (time-2), family members observed patients driving for at least 3 hours over 4 weeks and rated their driving performance using the DPI. Results: At time-1, patients were significantly impaired on automated SPI measures of driving skill, including: speed and steering control, accidents, and vigilance to a divided-attention task. These simulator indices significantly predicted the following aspects of observed driving performance at time-2: handling of automobile controls, regulation of vehicle speed and direction, higher-order judgment and self-control, as well as a trend-level association with car accidents. Automated measures of simulator skill (SPI) were more sensitive and accurate than observational measures of simulator skill (DPI) in predicting actual driving performance. To our surprise, the road test results at time-1 showed no significant relation to driving performance at time-2. Conclusion: Simulator-based assessment of patients with brain injuries can provide ecologically valid measures that, in some cases, may be more sensitive than a traditional road test as predictors of long-term driving performance in the community.

The Structure of Postconcussive Symptoms in 3 Us Military Samples

Objective:To evaluate alternative models of symptom clusters for the 22-item Neurobehavioral Symptom Inventory. Participants:Three military samples, including 2 nonclinical samples (n = 2420, n = 4244) and 1 sample of individuals with recent head injury (n = 617). Methods:In the first sample, exploratory factor analysis of Neurobehavioral Symptom Inventory responses was performed with tests of significant factors and model fit. In the other 2 samples, confirmatory factor analysis evaluated the fit of 3 models: 2- and 3-factor models based on the initial exploratory factor analysis, and a 9-factor model based on prior research. Main Outcome Measures:The exploratory factor analysis used 2 tests for the number of factors: Parallel Analysis and Minimum Average Partial test. Confirmatory factor analysis models were evaluated using 2 measures of model fit, Root Mean Square Error of Approximation and Comparative Fit Index. Results:Postconcussive symptoms can be described accurately by the 9 factors. However, the model of 3 intercorrelated factors, reflecting cognitive, affective, and somatic/sensory symptoms, fits the data more parsimoniously with little loss in model fit. Conclusion:Although the 9-cluster result from prior research provides a valid description of the relations among items of the inventory, a 3-factor model, consisting of somatic/sensory, affective, and cognitive factors, provides nearly as good a fit to the data, with greater parsimony. We encourage clinicians and researchers to conceptualize the Neurobehavioral Symptom Inventory in terms of 3 coherent clusters of symptoms rather than as 22 individual items.

Persistent problems after traumatic brain injury: The need for long-term follow-up and coordinated care.

Henry L. Lew, MD, PhD; Coauthors include: John H. Poole, PhD; Sylvia B. Guillory, BS; Rose Marie Salerno, RN; Gregory Leskin, PhD; Barbara Sigford, MD, PhD Traumatic brain injury (TBI) is one of the leading causes of death and long-term disability in the United States [1]. Survivors of TBI experience various problems, including physical, cognitive, emotional, and community integration issues. Established in 1992, the Defense and Veterans Brain Injury Center (DVBIC) coordinates nine healthcare centers—two civilian, three military, and four Department of Veterans Affairs (VA) sites—that provide evidence-based treatment, education, and research on TBI (www.dvbic.org). Patients with TBI who are admitted to regional medical centers within the DVBIC network receive multidisciplinary assessment and rehabilitation by experts in physiatry (physical medicine and rehabilitation [PM&R]), neurology, neuropsychology, psychiatry, and other allied health professions. After discharge, DVBIC patients are also advised to return for onsite, 3-day comprehensive follow-up evaluations at 1 and 2 years postinjury. To determine the prevalence of a constellation of problems faced by the TBI patients admitted to our Palo Alto VA facility, we performed an extensive chart review on 138 patients who had sustained closed head injuries. These patients were enrolled in the DVBIC program at the Palo Alto VA from 1993 to 2003 and ranged in age from 18 to 76 (median = 27). Of these patients, 71 percent returned for either the 1 or 2 year follow-up at the Palo Alto site and 49 percent returned for both follow-ups. Compared with the patients who returned for both follow-ups, those who missed one or both follow-ups had more emotional symptoms at baseline (mean = 3.2 vs 2.4 symptoms/patient, p < 0.005) but fewer cognitive impairments (4.2 vs 5.9 impairments/patient, p < 0.001). The two groups did not differ significantly in age or the frequency of physical symptoms at baseline (4.4 vs 4.6, p = 0.5). The present analysis focused on those who returned for both follow-ups. We evaluated the patients’ problems in four areas: physical, cognitive, emotional, and community integration, using standardized neurocognitive tests and structured clinical interviews. Physical problems were mainly documented by the physiatrist and included pain, motor weakness, gait abnormality, seizure, dizziness, and fatigue. Cognitive deficits were primarily measured by the neuropsychologist and included deficits in attention/concentration, processing speed, memory, problem-solving, executive organization, and safety judgment. Emotional issues, mainly identified by the psychiatrist, included depressed mood, anxiety, posttraumatic distress, suicidal ideation, irritability, and disinhibition. Community integration issues, primarily evaluated by the occupational therapist, included problems with self-care, money management, employment, community accessibility, recreational activities, and adjustment to limitations. As Figure 1 demonstrates, 90 percent or more of TBI patients had at least one problem in each category at baseline, i.e., during the first week of their inpatient admission for acute rehabilitation. During the following 2 years, the frequency of physical problems decreased from 100 to 84 percent,

Temporal stability of auditory event-related potentials in healthy individuals and patients with traumatic brain injury.

Summary: Historically, cognitive event-related potentials (ERPs) have received limited acceptance for clinical use due to lack of evidence for their reliability. However, recent advances in computer technology and artifact rejection methods have greatly enhanced the fidelity of ERP measurements. The present study examined the test-retest reliability of ERP measurement by using current data processing methods. We assessed the temporal stability of the most commonly used ERP paradigm, auditory pure-tone “odd ball” detection, and compared it with other commonly used clinical measures reported in the literature. Auditory ERPs were collected in 19 healthy subjects and 7 patients with traumatic brain injury at two time points, 2 days to 2 months apart. Test-retest reliability was calculated for four ERP components: N1, MMN (mismatch negativity), P3, and N4. In healthy subjects, temporal stabilities of these four commonly studied ERP components’ amplitude measurements were moderate to high, with intraclass correlations ranging from 0.6 to 0.8. In contrast, in patients with traumatic brain injury, ERPs were stable only for the N1 component (intraclass correlation = 0.7).

The potential utility of driving simulators in the cognitive rehabilitation of combat-returnees with traumatic brain injury.

A large number of Operation Enduring Freedom/Operation Iraqi Freedom returnees are seeking DOD and VA rehabilitative care for war-related traumatic brain injury (TBI). This article reviews evidence on the utility of driving simulators as tools for assessment and training in TBI rehabilitation. Traditionally, cognitive rehabilitation has been shown to improve specific cognitive skills. However, there are few studies and only weak evidence to show that these gains transfer to everyday activities. Theoretically, modern driving simulators may be useful in cognitive rehabilitation because they can systematically present realistic and interesting tasks that approximate driving activities, while automatically monitoring performance. The use of simulation technology for patients with TBI provides cognitive stimulation in an ecologically compatible setting, without the risks associated with a corresponding real-world experience. The utility, limitations, and future directions for the use of driving simulator in the rehabilitation of patients with war-related TBI are discussed.

The Effects of Increasing Stimulus Complexity in Event-related Potentials and Reaction Time Testing: Clinical Applications in Evaluating Patients with Traumatic Brain Injury

Summary: This study compared the effectiveness of P300 event related potentials (ERPs) and reaction time (RT) in discriminating patients with traumatic brain injury (TBI) from healthy control subjects. In particular, we examined how the use of more complex, ecologically relevant stimuli may affect the clinical utility of these tasks. We also evaluated how length of posttraumatic amnesia (PTA) and loss of consciousness (LOC) related to P300 and RT measures in our patient sample. There were 22 subjects (11 patients with TBI and 11 age-matched healthy control subjects). Four stimulus detection procedures were used: two using simple, conventional stimuli (auditory tone discrimination, AT; visual color discrimination, VC), and two using complex, ecologically relevant stimuli in the auditory and visual modalities (auditory word category discrimination, AWC; visual facial affect discrimination, VFA). Our results showed that RT measures were more effective in identifying TBI patients when complex stimuli were used (AWC and VFA). On the other hand, ERP measures were more effective in identifying TBI patients when simple stimuli were used (AT and VC). We also found a remarkably high correlation between duration of PTA and P300 amplitude.

Long-term outcomes after moderate-to-severe traumatic brain injury among military veterans: Successes and challenges

Abstract Objective: To assess long-term outcomes after traumatic brain injury (TBI) among veterans and service members. Setting: Regional Veterans Affairs medical centre. Participants: One hundred and eighteen veterans and military personnel, aged 23–70 years (median = 35 years), 90% male, had moderate-to-severe TBI (82% in coma > 1 day, 85% amnesic > 7 days), followed by acute interdisciplinary rehabilitation 5–16 years ago (median = 8 years). Design: Cross-sectional analysis of live interviews conducted via telephone. Main measures: TBI follow-up interview (occupational, social, cognitive, neurologic and psychiatric ratings), Community Integration Questionnaire, Disability Rating Scale (four indices of independent function) and Satisfaction with Life Scale. Results: At follow-up, 52% of participants were working or attending school; 34% ended or began marriages after TBI, but the overall proportion married changed little. Finally, 22% were still moderately-to-severely disabled. However, 62% of participants judged themselves to be as satisfied or more satisfied with life than before injury. Injury severity, especially post-traumatic amnesia, was correlated with poorer outcomes in all functional domains. Conclusions: After moderate–severe TBI, most veterans assume productive roles and are satisfied with life. However, widespread difficulties and functional limitations persist. These findings suggest that veteran and military healthcare systems should continue periodic, comprehensive follow-up evaluations long after moderate-to-severe TBI.

Service needs and barriers to care five or more years after moderate to severe TBI among Veterans

ABSTRACT Primary objective: The objective of this paper is to identify the most frequent service needs, factors associated with needs, and barriers to care among Veterans and service members five or more years after moderate to severe traumatic brain injury (TBI). Research design: Survey administered via telephone 5–16 years after injury (median eight years) and subsequent acute inpatient rehabilitation at a regional Veterans Affairs (VA) medical centre. Methods and procedures: Participants were 119 Veterans and military personnel, aged 23–70 (median 35), 90% male. Demographics, injury characteristics, service needs, whether needs were addressed, barriers to care, health and general functioning were assessed. Main outcomes and results: The most frequent needs were for help with memory, information about available services and managing stress. Obtaining information about services was the most consistently un-addressed need; managing stress was the most consistently addressed need. Cognitive and psychiatric symptoms and alienation from community were associated with needs going un-addressed. Participants treated after an expansion of TBI services at the study site reported fewer un-addressed needs. Not knowing where to get help was the most common barrier to care. Conclusion: Repeated outreach, assessment of needs and education about available services are needed throughout Veterans’ lifespan after moderate to severe TBI.

Prospective Tracking and Analysis of Traumatic Brain Injury in Veterans and Military Personnel.

OBJECTIVE To describe the ongoing Clinical Tracking Form (CTF) study of the Defense and Veterans Brain Injury Center (DVBIC). DESIGN Prospective longitudinal study. Data at baseline and postinjury are collected on participants through interview and questionnaire, review of medical records, and periodic follow-ups throughout their lifetime. SETTING A regional DVBIC site located at a Veterans Affairs Medical Center. PARTICIPANTS Participants (N=211; age range, 18-75y) were enrolled between January 1, 2005, and December 31, 2012, at a regional DVBIC site. INTERVENTION Not applicable. MAIN OUTCOME MEASURES Injury information, functioning, and psychological health. RESULTS Sixty percent of 211 participants were identified as having severe traumatic brain injuries (TBIs), 14% moderate TBIs, and 26% mild TBIs. Of these 211 participants, 79% sustained closed head injuries, 15% penetrating head injuries, and 6% were not reported. Comparing the severity of TBI in combat versus stateside situations, most of the mild injuries (71%) occurred in combat locations, while most of the severe injuries (62%) occurred in the United States. Among those injured in combat, blast-related TBIs (82%) greatly outnumbered non-blast-related TBIs, regardless of severity. CONCLUSIONS The CTF study serves as a significant resource of data to understand the effect and outcomes of TBI in the military population. The lifelong experience of military veterans across the full spectrum of TBI and recovery will be recorded through the CTF, and will translate into more informed clinical decisions and educational efforts to guide future research pathways.