The predictive validity of a brief inpatient neuropsychologic battery for persons with traumatic brain injury

Affective state and community integration after traumatic brain injury

Previous studies investigating the relationship between affective state and community integration have focused primarily on the influence of depression and anxiety. In addition, they have focused on frequency of participation in various activities, failing to address an individual's subjective satisfaction with participation. The purpose of this study was to examine how affective state contributes to frequency of participation and satisfaction with participation after traumatic brain injury among participants with and without a current major depressive episode. Sixty-four community-dwelling participants with a history of complicated mild-to-severe traumatic brain injury participated in this cross-sectional cohort study. High positive affect contributed significantly to frequency of participation (β = 0.401, P = 0.001), and both high positive affect and low negative affect significantly contributed to better satisfaction with participation (F2,61 = 13.63, P < 0.001). Further investigation to assess the direction of these relationships may better inform effective targets for intervention. These findings highlight the importance of assessing affective state after traumatic brain injury and incorporating a subjective measure of participation when considering community integration outcomes.

Cognitive dysfunction in postural tachycardia syndrome

Mental clouding is an almost universal complaint among patients with postural tachycardia syndrome (POTS) but remains poorly understood. Thus, we have determined whether POTS patients exhibit deficits during neuropsychological testing relative to healthy subjects. A comprehensive battery of validated neuropsychological tests was administered to 28 female POTS patients and 24 healthy subjects in a semi-recumbent position. Healthy subjects were matched to POTS patients on age and gender. Selective attention, a primary outcome measure, and cognitive processing speed were reduced in POTS patients compared with healthy subjects (Ruff 2&7 Speed t-score: 40±9 compared with 49±8; P=0.009; Symbol Digit Modalities Test t-score: 45±12 compared with 51±8; P=0.011). Measures of executive function were also lower in POTS patients (Trails B t-score: 46±8 compared with 52±8; P=0.007; Stroop Word Color t-score: 45±10 compared with 56±8; P=0.001), suggesting difficulties in tracking and mental flexibility. Measures of sustained attention, psychomotor speed, memory function or verbal fluency were not significantly different between groups. The present study provides evidence for deficits in selective attention and cognitive processing in patients with POTS, in the seated position when orthostatic stress is minimized. In contrast, other measures of cognitive function, including memory assessments, were not impaired in these patients, suggesting selectivity in these deficits. These findings provide new insight into the profile of cognitive dysfunction in POTS and provide the basis for further studies to identify clinical strategies to better manage the mental clouding associated with this condition.

Education quality, reading recognition, and racial differences in the neuropsychological outcome from traumatic brain injury

Ethnically diverse examinees tend to perform lower on neuropsychological tests. The practice of adjusting normative comparisons for the education level and/or race to prevent overpathologizing low scores is problematic. Education quality, as measured by reading recognition, appears to be a more accurate benchmark for premorbid functioning in certain populations. The present study aimed to extend this line of research to traumatic brain injury (TBI). We hypothesized that a measure of reading recognition, the Wechsler Test of Adult Reading (WTAR), would account for racial differences in neuropsychological performance after TBI. Fifty participants (72% African American, 28% Caucasian) with moderate to severe TBI underwent neuropsychological testing at 1-year post-injury. Reading recognition accounted for all the same variance in neuropsychological performance as race and education (together), as well as considerable additional variance. Estimation of premorbid functioning in African Americans with TBI could be refined by considering reading recognition.

Heterogeneity in Trail Making Test performance in OEF/OIF/OND veterans with mild traumatic brain injury

This study used cluster analysis to examine variability in Trail Making Test (TMT) performance in a sample of Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) veterans referred for mild traumatic brain injury (mTBI). Three clusters were extracted, two of which were characterized by level of performance and the third with a unique performance pattern characterized by slow performance on the TMT B (Low B). Clusters did not differ on demographic or psychiatric variables. The Above Average cluster had better performance on measures of processing speed, working memory, and phonemic fluency compared with the Low B cluster. Results suggest that a subset of patients with mTBI perform poorly on TMT B, which subsequently predicts poorer cognitive functioning on several other neuropsychological measures. This subset may be vulnerable to cognitive changes in the context of mTBI and multiple comorbidities while a number of other patients remain cognitively unaffected under the same circumstances.

Cannabis users have higher premorbid IQ than other patients with first onset psychosis

BACKGROUND

A number of studies have reported that patients with psychosis who use cannabis have better cognitive performance than those who do not. This is surprising as cannabis can impair cognition in healthy subjects. An obvious question is whether the better current performance of psychotic patients who have used cannabis is a reflection of their having a higher premorbid IQ than those psychotic patients who haven't used cannabis.

AIM

In a sample of patients at their first episode of psychosis, we tested the hypothesis that patients who smoked cannabis would have a higher premorbid IQ than patients who did not.

METHODOLOGY

279 participants (119 patients and 160 healthy controls) were assessed in order to obtain current and premorbid IQ measures and detailed information on cannabis use. We examined the association between cannabis use and both premorbid and current IQ in patients and controls.

RESULTS

Patients who had ever smoked cannabis had significantly higher current (p<.001) and premorbid IQ (p=.004) compared to patients who had never used cannabis. This difference was not found among controls.

CONCLUSIONS

These findings suggest that the better cognitive performance of patients with their first episode of psychosis who have used cannabis compared with those who haven't is due to the better premorbid IQ of the former.

Descriptive characteristics and rehabilitation outcomes in active duty military personnel and veterans with disorders of consciousness with combat- and noncombat-related brain injury

OBJECTIVE

To report the injury and demographic characteristics, medical course, and rehabilitation outcome for a consecutive series of veterans and active duty military personnel with combat- and noncombat-related brain injury and disorder of consciousness (DOC) at the time of rehabilitation admission.

DESIGN

Retrospective study.

SETTING

Rehabilitation center.

PARTICIPANTS

From January 2004 to October 2009, persons (N=1654) were admitted to the Polytrauma Rehabilitation System of Care. This study focused on the N=122 persons admitted with a DOC. Participants with a DOC were primarily men (96%), on active duty (82%), ≥12 years of education, and a median age of 25. Brain injury etiologies included mixed blast trauma (24%), penetrating (8%), other trauma (56%), and nontrauma (13%). Median initial Glasgow Coma Scale score was 3, and rehabilitation admission Glasgow Coma Scale score was 8. Individuals were admitted for acute neurorehabilitation approximately 51 days postinjury with a median rehabilitation length of stay of 132 days.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Recovery of consciousness and the FIM instrument.

RESULTS

Most participants emerged to regain consciousness during neurorehabilitation (64%). Average gains ± SD on the FIM cognitive and motor subscales were 19 ± 25 and 7 ± 8, respectively. Common medical complications included spasticity (70%), dysautonomia (34%), seizure occurrence (30%), and intracranial infection (22%). Differential outcomes were observed across etiologies, particularly for those with blast-related brain injury etiology.

CONCLUSIONS

Despite complex comorbidities, optimistic outcomes were observed. Individuals with severe head injury because of blast-related etiologies have different outcomes and comorbidities observed. Health-services research with a focus on prevention of comorbidities is needed to inform optimal models of care, particularly for combat injured soldiers with blast-related injuries.

Incremental validity of neuropsychological evaluations to computed tomography in predicting long-term outcomes after traumatic brain injury

This study evaluated the incremental utility of neuropsychological tests to computed tomography (CT) in predicting long-term outcomes of adults with moderate to severe traumatic brain injury (TBI). Participants were 288 adults with mild complicated, moderate, and severe TBI. Longitudinal data were evaluated during inpatient status in an urban rehabilitation hospital with a TBI Model System, as well as 1 and 2 years post injury. Predictors including demographic characteristics, injury severity, CT characteristics, and neuropsychological evaluations were regressed to outcomes of disability, life satisfaction, and employment at 1 and 2 years post injury. Prediction of life satisfaction was not improved with the use of CT characteristics or neuropsychological tests, but prediction of return to work was improved by these variables at 2 years post injury. Neuropsychological evaluations uniquely contributed to outcome predictions of functional disability, even after considering demographic and injury severity characteristics, including information from CT. In contrast, CT characteristics were not predictive of long-term functional disability at 1 or 2 years post TBI. Taken together, the findings indicate that neuropsychological tests add unique predictive information for long-term functional outcomes after TBI.

Trail Making Test: regression-based norms for the Portuguese population

The main goal of this study was to produce normative data for the Portuguese population on the Trail Making Test (TMT). The study included 1,038 community-dwelling individuals aged between 18 and 93 years, who had educational backgrounds ranging from 3 to 22 years. The results showed that sex, age, and education were significantly associated with TMT performance. These demographic characteristics accounted for 57% of the performance variance at part A and 50% at part B. The normative data are presented as regression-based algorithms to adjust direct and derived test scores for sex, age, and education. The adjusted scores' percentile distributions and their correspondence with scaled scores are also provided.

Syndromics: a bioinformatics approach for neurotrauma research

Substantial scientific progress has been made in the past 50 years in delineating many of the biological mechanisms involved in the primary and secondary injuries following trauma to the spinal cord and brain. These advances have highlighted numerous potential therapeutic approaches that may help restore function after injury. Despite these advances, bench-to-bedside translation has remained elusive. Translational testing of novel therapies requires standardized measures of function for comparison across different laboratories, paradigms, and species. Although numerous functional assessments have been developed in animal models, it remains unclear how to best integrate this information to describe the complete translational "syndrome" produced by neurotrauma. The present paper describes a multivariate statistical framework for integrating diverse neurotrauma data and reviews the few papers to date that have taken an information-intensive approach for basic neurotrauma research. We argue that these papers can be described as the seminal works of a new field that we call "syndromics", which aim to apply informatics tools to disease models to characterize the full set of mechanistic inter-relationships from multi-scale data. In the future, centralized databases of raw neurotrauma data will enable better syndromic approaches and aid future translational research, leading to more efficient testing regimens and more clinically relevant findings.

Addressing neuropsychiatric disturbances during rehabilitation after traumatic brain injury: current and future methods

Cognitive, emotional, behavioral, and sensorimotor disturbances are the principal clinical manifestations of traumatic brain injury (TBI) throughout the early postinjury period. These post-traumatic neuropsychiatric disturbances present substantial challenges to patients, their families, and clinicians providing their rehabilitative care, the optimal approaches to which remain incompletely developed. In this article, a neuropsychiairically informed, neurobiologically anchored approach to understanding and meeting challenges is described. The foundation for thai approach is laid, with a review of clinical case definitions of TBI and clarification of their intended referents. The differential diagnosis of event-related neuropsychiatric disturbances is considered next, after which the clinical and neurobiological heterogeneity within the diagnostic category of TBI are discussed. The clinical manifestations of biomechanical force-induced brain dysfunction are described as a state of post-traumatic encephalopathy (PTE) comprising several phenomenologically distinct stages, PTE is then used as a framework for understanding and clinically evaluating the neuropsychiatric sequelae of TBI encountered commonly during the early post-injury rehabilitation period, and for considering the types and timings of neurorehabilitative interventions. Finally, directions for future research that may address productively the challenges to TBI rehabilitation presented by neuropsychiatric disturbances are considered.

Longitudinal outcome of patients with disordered consciousness in the NIDRR TBI Model Systems Programs

Few studies address the course of recovery from prolonged disorders of consciousness (DOC) after severe traumatic brain injury (TBI). This study examined acute and long-term outcomes of persons with DOC admitted to acute inpatient rehabilitation within the National Institute on Disability and Rehabilitation Research (NIDRR) TBI Model Systems Programs (TBIMS). Of 9028 persons enrolled from 1988 to 2009, 396 from 20 centers met study criteria. Participants were primarily male (73%), Caucasian (67%), injured in motor vehicle collision (66%), with a median age of 28, and emergency department Glasgow Coma Scale (GCS) score of 3. Participant status was evaluated at acute rehabilitation admission and discharge and at 1, 2, and 5 years post-injury. During inpatient rehabilitation, 268 of 396 (68%) regained consciousness and 91 (23%) emerged from post-traumatic amnesia (PTA). Participants demonstrated significant improvements on GCS (z=16.135, p≤0.001) and Functional Independence Measure (FIM) (z=15.584, p≤0.001) from rehabilitation admission (median GCS=9; FIM=18) to discharge (median GCS=14; FIM=43). Of 337 with at least one follow-up visit, 28 (8%) had died by 2.1 years (mean) after discharge. Among survivors, 66 (21%) improved to become capable of living without in-house supervision, and 63 demonstrated employment potential using the Disability Rating Scale (DRS). Participants with follow-up data at 1, 2, and 5 years post-injury (n=108) demonstrated significant improvement across all follow-up evaluations on the FIM Cognitive and Supervision Rating Scale (p<0.01). Significant improvements were observed on the DRS and FIM Motor at 1 and 2 years post-injury (p<0.01). Persons with DOC at the time of admission to inpatient rehabilitation showed functional improvement throughout early recovery and in years post-injury.

Effects of family and caregiver psychosocial functioning on outcomes in persons with traumatic brain injury

OBJECTIVES

To examine the predictive value of caregiver/family status to well-being of persons with brain injury and to examine whether perceived social support to caregivers moderates their well-being.

PARTICIPANTS

One hundred nine pairs of adults, a caregiver, and an individual with TBI.

MAIN MEASURES

Brief Symptom Inventory-18, Satisfaction With Life Scale; Disability Rating Scale; Social Provision Scale, Family Assessment Device, and Disability Rating Scale.

RESULTS

Canonical correlation indicated the presence of a relationship between well-being in TBI and caregiver participants. Two canonical variates accounted for 47.5% variance. Poor psychological well-being among persons with TBI was associated with poor caregiver perceived social support and poor familial behavioral control. Individuals with high disability also had caregivers with poorer psychological well-being. In post hoc multiple regressions, caregiver/family psychosocial characteristics added unique prediction of outcome for individuals with TBI. Hierarchical multiple regressions provided evidence that social support of caregivers moderates outcome status for individuals with TBI.

CONCLUSIONS

Future research efforts should focus on understanding of the specific mechanisms of reciprocal effects, to help design future therapy.

Criterion validity of the Delis-Kaplan Executive Function System (D-KEFS) fluency subtests after traumatic brain injury

The performance of 65 patients with complicated mild-severe traumatic brain injury was evaluated on the Verbal and Design Fluency subtests of the Delis-Kaplan Executive Function System (D-KEFS), and compared with that of 65 demographically matched healthy controls. There were statistically significant group differences on Letter Fluency and Category Switching but not on any of the Design Fluency tasks. Combined, these two Verbal Fluency subtests had a classification accuracy of 65.39%, associated with a likelihood ratio of 1.87. The impact of length of coma on Letter Fluency performance but not Category Switching was mediated at least in part by processing speed. The findings suggest modest criterion validity of some of the D-KEFS Verbal Fluency subtests in the assessment of patients with complicated mild-severe traumatic brain injury.

A critical review of the literature on early rehabilitation of patients with post-traumatic amnesia in acute care

AIMS AND OBJECTIVES

To identify the effect of early rehabilitation of patients with post-traumatic amnesia in patients with traumatic brain injury, to review and critically assess evidence related to the timing of intervention and to identify the effect on outcome of a specific neurological rehabilitation in acute care.

BACKGROUND

Up to 70% of patients with traumatic brain injury will experience post-traumatic amnesia. Although duration of post-traumatic amnesia is correlated negatively with outcome for patients with traumatic brain injury, there is limited evidence relating to what influence timing and effect may have on enhancing early rehabilitation patient outcomes.

DESIGN

A critical literature review.

METHODS

Searches for systematic reviews were undertaken in Medline, CINAHL, Cochrane, PSYC INFO and Neurotraume databases. The efficacy of intervention and timing was classified based on a hierarchy of study designs for questions about health care interventions based on soundness of design.

RESULTS

Six reviews and 11 original studies were included and comprised the review. Many studies used weak designs and small sample size, thus limiting their ability to control confusing variables and outcomes. Few studies included papers with the information about timing and effect of early post-traumatic amnesia intervention. Only one study showed an effect of a reality orientation programme in acute care. Although there was no significant detail reported on the possibility of reducing the post-traumatic amnesia period, the study showed clinical relevance.

CONCLUSION

This review highlights the limited evidence of the effect of early rehabilitation of patients with post-traumatic amnesia. Future research should be conducted to identify the effectiveness of early intervention.

RELEVANCE TO CLINICAL PRACTICE

Although nurses are treating patients with post-traumatic amnesia without systematic assessment, the limited evidence available does little to direct nurses as to the best approach to start early rehabilitation of post-traumatic amnesia to promote good outcomes.

Cognitive correlates with functional outcomes after anoxic brain injury: a case-controlled comparison with traumatic brain injury

OBJECTIVES

To assess the effectiveness of inpatient rehabilitation in adults who have sustained an anoxic brain injury (AnBI). Secondly, to identify areas of cognition that predict functional outcomes at discharge.

DESIGN

Retrospective, matched case-controlled study.

METHODS

Ten patients with moderate-to-severe AnBI and 10 patients with traumatic brain injury (TBI), treated in an inpatient neurorehabilitation programme, were matched on age, acute care length of stay and admission Functional Independence Measure (FIM). Functional outcome was assessed using the FIM and Disability Rating Scale (DRS).

RESULTS

Patients with AnBI performed worse on all measures of functional outcome relative to patients with TBI. Patients with AnBI achieved significantly lower FIM motor and cognitive gain compared with patients with TBI (11.5, SD 13.6 vs. 31.0, SD 19.7 and 2.4, SD 3.9 vs. 7.5, SD 4.2, respectively (p < 0.02)). DRS data showed similar trends of functional improvement between the groups. Several neuropsychometric tests correlated with functional outcome (p < 0.01).

CONCLUSIONS

Patients with AnBI had worse functional outcomes following rehabilitation than patients with TBI, confirming the results of previous reports. Poor cognitive function predicted poor functional outcomes on the FIM and somewhat on the DRS. Research is needed to assess why these differences occur and to improve or develop new effective rehabilitation treatments for AnBI.

Evaluation and Management of Posttraumatic Cognitive Impairments

Psychiatrists are increasingly called upon to care for individuals with cognitive, emotional, and behavioral disturbances after TBI, especially in settings serving military service personnel and Veterans. In both the early and late post-injury periods, cognitive impairments contribute to disability among persons with TBI and are potentially substantial sources of suffering for persons with TBI and their families. In this article, the differential diagnosis, evaluation, and management of posttraumatic cognitive complaints is reviewed. The importance of pre-treatment evaluation as well as consideration of non-cognitive contributors to cognitive problems and functional limitations is emphasized first. The course of recovery after TBI, framed as a progression through posttraumatic encephalopathy, is reviewed next and used to anchor the evaluation and treatment of posttraumatic cognitive impairments in relation to injury severity as well as time post-injury. Finally, pharmacologic and rehabilitative interventions that may facilitate cognitive and functional recovery at each stage of posttraumatic encephalopathy are presented.

Functional cooking skills and neuropsychological functioning in patients with stroke: an ecological validity study

Efforts to relate neuropsychological performance to real-world task functioning have predominantly yielded lackluster results, typically with neuropsychological performance accounting for modest amounts of variance in function. Nonetheless, the ecological validity of neuropsychological measures for predicting functional abilities remains a strong research interest and clinical necessity. This study relates neuropsychological performance to performance on a standardised cooking task (Rabideau Kitchen Evaluation - Revised; RKE-R) in persons with stroke. Results showed that while the composite score of mean neuropsychological performance had the largest association with meal preparation, several neuropsychological measures were significantly related to the RKE-R. Groups of left and right hemisphere stroke patients were not significantly different in terms of RKE-R performance. These results suggest that functional cooking task performance is related to intact cognitive abilities in delayed verbal memory, simple auditory attention, and visuospatial skills, as well as overall cognitive performance. Implications for neuropsychologists are discussed.

A different view of lactate in trauma patients: protecting the injured brain

BACKGROUND

The relationship between lactate and head injury is controversial. We sought to determine the relationship between initial serum lactate, severity of head injury, and outcome. We hypothesized that lactate is elevated in head injured patients, and that initial serum lactate increases as the severity of head injury increases. Furthermore, lactate may be neuroprotective and improve neurologic outcomes.

MATERIALS AND METHODS

We identified normotensive adult patients over a 6-y period at our university-based urban trauma center with isolated blunt head injury. We performed univariate and multivariate analysis to examine the relationship between lactate and Glasgow coma scale (GCS). The correlation of admission lactate with survival and neurologic function was also examined.

RESULTS

There were 555 patients who met study criteria. While controlling for injury severity score and age, increased lactate was associated with more severe head injury (P<0.0001). The admission lactate was 2.2+/-0.07, 3.7+/-0.7, and 4.7+/-0.8 mmol/L in patients with mild, moderate, and severe head injury respectively (P<0.01). Patients with moderate or severe head injury and an admission lactate>5 were more likely to have a normal mental status on discharge (P<0.0001).

CONCLUSIONS

In normotensive isolated head injured patients, there was an increase in serum lactate as head injuries became more severe. Since lactate is a readily available fuel source of the injured brain, this may be a mechanism by which brain function is preserved in trauma patients. Elevations in lactate due to anaerobic metabolism in trauma patients may have beneficial effects by protecting the brain during injury.

Traumatic Brain Injury Model Systems of Care 2002-2007

During the years 2002 to 2007, 16 Traumatic Brain Injury Model Systems of Care (TBIMS) were funded by the National Institute on Disability and Rehabilitation Research to conduct site-specific and collaborative research projects, including contribution to a longitudinal database, within comprehensive systems of care specialized for people with traumatic brain injury. The TBIMS program has been in existence since 1987 and has undergone significant modifications over these years. Herein I provide an overview of the changes that occurred in the 2002-2007 funding cycle, the research initiatives that were carried out during that time, and brief descriptions of the 13 original TBIMS research articles included in this issue of Archives.