Classification Schema of Posttraumatic Amnesia Duration-Based Injury Severity Relative to 1-Year Outcome: Analysis of Individuals with Moderate and Severe Traumatic Brain Injury

Prolonged duration of post-traumatic amnesia: A sensitive classification for predicting cognitive outcomes in children recovering from traumatic brain injury

OBJECTIVE

A paucity of data exists regarding the duration of post-traumatic amnesia (PTA) as a predictor of cognitive functioning among children after traumatic brain injury (TBI). The study aimed to assess the relationship between PTA duration and areas of neurocognitive function among the pediatric population in the sub-acute phase of recovery and rehabilitation.

METHODS

Data were collected from medical files on 103 children aged 5.5-16.5 hospitalized at a pediatric rehabilitation department with a diagnosis of moderate-severe TBI (msTBI) between the years 2004-2019. The Children Orientation and Amnesia Test was used to evaluate PTA duration. Measures of high-order cognitive abilities of attention and executive function were collected using the Test of Everyday Attention-Child version (TEA-Ch).

RESULTS

Three PTA duration groups were assembled out of a cluster analysis: "Long PTA" (M = 21 days), "Very Long PTA" (M = 47 days), and "Extremely Long PTA" (M = 94 days). Analyses revealed that the "Long PTA" group preformed significantly better than the "Very Long PTA" and "Extremely Long PTA" groups on all TEA-Ch measures, that is, Selective Attention, Attentional Control Switching, and Sustained Attention.

CONCLUSIONS

This study is the first to demonstrate that PTA duration is a useful predictor of high-order cognitive functions among children with msTBI in the sub-acute phase of recovery and rehabilitation. The findings emphasize the importance of using a more sensitive classification of prolonged PTA durations to improve outcome prediction and allocation of resources to those who can benefit most after severe brain injuries.

Effect of Race and Nativity on Functional Outcomes Following Traumatic Brain Injury Among Asian, Hispanic, and Non-Hispanic White Survivors in the United States: A NIDILRR TBI Model Systems Study

OBJECTIVE

To compare the racial/ethnic differences in traumatic brain injury (TBI) recovery among Asians, Hispanics, and Whites, and explore the effect of nativity in the recovery process.

SETTING

Six Traumatic Brain Injury Model Systems (TBIMS) centers.

PARTICIPANTS

In total, 7953 patients who had at least 1 severe TBI between 2000 and 2016 were admitted to one of the TBIMS centers.

DESIGN

Secondary data analysis.

MAIN MEASURES

Functional Independent Measure (FIM instrument) ratings.

RESULTS

Asians had the lowest injury severity at admission, but they failed to make the improvements made by the Hispanics and the Whites between the rehabilitation discharge and the 1-year follow-up. The magnitude of improvement made by the foreign-born Asians was less than that made by their native-born counterparts. Both Asian and the Hispanic groups had lower functional outcomes at the 1-year follow-up, and the differences in functional outcomes between the Asian and Hispanic groups were not statistically significant. The above racial/ethnic disparities in functional outcomes were not fully explained by differences in sociodemographic status, injury characteristics, and immigration-related factors. The effect of nativity was mediated by covariates.

CONCLUSIONS

This study reveals racial/ethnic disparities post-TBI functional recovery. Despite lower injury severity and apparent financial resource advantages, Asians did not experience better functional outcomes. Although the effect of nativity was not established in this study, contextual factors related to ethnicity and immigration experiences should be further investigated.

Sleep from acute to chronic traumatic brain injury and cognitive outcomes

STUDY OBJECTIVES

Traumatic brain injuries (TBIs) cause persistent cerebral damage and cognitive deficits. Because sleep may be a critical factor for brain recovery, we characterized the sleep of patients with TBI from early hospitalization to years post-injury and explored the hypothesis that better sleep during hospitalization predicts more favorable long-term cognitive outcomes.

METHODS

We tested patients with moderate-to-severe TBI in the hospitalized (n = 11) and chronic (n = 43) stages using full-night polysomnography, with 82% of the hospitalized group being retested years post-injury. Hospitalized patients with severe orthopedic and/or spinal cord injury (n = 14) and healthy participants (n = 36) were tested as controls for the hospitalized and chronic TBI groups, respectively. Groups had similar age and sex and were compared for sleep characteristics, including slow waves and spindles. For patients with TBI, associations between sleep during hospitalization and long-term memory and executive function were assessed.

RESULTS

Hospitalized patients with TBI or orthopedic injuries had lower sleep efficiency, higher wake after sleep onset, and lower spindle density than the chronic TBI and healthy control groups, but only hospitalized patients with brain injury had an increased proportion of slow-wave sleep. During hospitalization for TBI, less fragmented sleep, more slow-wave sleep, and higher spindle density were associated to more favorable cognitive outcomes years post-injury, while injury severity markers were not associated with these outcomes.

CONCLUSION

These findings highlight the importance of sleep following TBI, as it could be a strong predictor of neurological recovery, either as a promoter or an early marker of cognitive outcomes.

Return to School Outcomes among Adults with TBI One Year After Rehabilitation Discharge: A TBIMS Study

OBJECTIVE

To examine return to school outcomes 1 year after traumatic brain injury (TBI) rehabilitation discharge.

DESIGN

Longitudinal observational study using Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) data at 1-year post-TBI.

SETTING

Inpatient rehabilitation centers using follow-up telephone calls.

INDIVIDUALS

Individuals (n = 237) enrolled in the TBIMS-NDB since 2001 between the ages of 18 and 59 years who were engaged in postsecondary education (full or part-time) before recorded TBI.

MAIN MEASURES

Return to school, categorized as in a postsecondary setting at first follow-up (reported hours in school greater than zero at one-year follow-up).

RESULTS

Using an alpha level of 0.05 binary logistic regression analysis identified four predictive variables. Significant predictors of return to school include being of lower age, possessing a higher level of functioning at discharge, reporting lower ratings of disability at discharge, and being able to use a vehicle independently for transportation.

CONCLUSION

Pursuit of higher education is a viable means of community reintegration after TBI. Some individuals with TBI face a myriad of barriers and challenges when returning to school. Study findings may facilitate understanding of how TBI affects return to school and community reintegration outcomes.

Cognitive-Communication Predictors of Employment Outcomes 1 and 5 Years Posttraumatic Brain Injury

OBJECTIVE

To examine changes in functional memory, problem solving, comprehension, expression, and social communication over the first 2 years posttraumatic brain injury (TBI) and the ability of each to predict return to work (RTW) outcomes at 1 year and 5 years postinjury.

DESIGN

Secondary analysis of data from a multicenter longitudinal cohort study.

SETTING

Acute inpatient rehabilitation facilities and community follow-up.

PARTICIPANTS

A total of 3543 individuals between 16 and 60 years of age who were competitively employed at the time of TBI and had completed year 1, year 2, and year 5 postinjury follow-ups.

MAIN OUTCOME MEASURES

Year 1 and year 5 RTW status (± competitively employed) at the time of study completion.

RESULTS

Greater function across each of the 5 cognitive-communication abilities was associated with RTW success at 1 year and 5 years post-TBI. At discharge, these 5 abilities showed comparable odds of predicting later employment. At year 1 and year 2 follow-ups, independence with problem solving was the most predictive of employment 5 years post-TBI, followed by social interaction, memory, expression, and comprehension.

CONCLUSIONS

An increased rehabilitation focus on functional memory, problem solving, comprehension, expression, and social interaction post-TBI has the potential to improve RTW outcomes.

Patterns of Functional Change Five to Ten Years after Moderate-Severe Traumatic Brain Injury

This study aims to characterize the patterns of functional change experienced between 5 and 10 years after moderate-severe traumatic brain injury (TBI). The study included TBI Model Systems national database participants (N = 372) at six sites who experienced TBI, received inpatient rehabilitation, and were followed at 5 and 10 years post-TBI. Outcome measures included self- or proxy-reported Functional Independence Measure (FIM^TM) structured interview at 5 and 10 years post-TBI and domain change indices (DCIs) at 10 years to assess subjective change over the previous 5 years. When all seven FIM and subjective DCI subscales were considered together, 69% reported improvement in at least one subscale and 41% reported decline in at least one subscale; 51% reported more domains improved than declined, and 20% reported more domains declined than improved. Age at injury, post-traumatic amnesia duration, FIM, and depression and anxiety at year 5 were associated with FIM change and DCI measures. Although most persons with moderate-severe TBI do not experience widespread change from year 5 to 10 on individual FIM subscales or perceived domain-specific subscales, the vast majority do report change in one or more domains, with more improvement than decline and more change in subjective DCI than in FIM. Clinicians and researchers should be alert to the possibility of both positive and deleterious changes many years after TBI.

Assessment and Management of Patients in the Acute Stages of Recovery after Traumatic Brain Injury in Adults: A Worldwide Survey

Most individuals with traumatic brain injury (TBI) experience a period of confusion after emergence from coma, termed post-traumatic amnesia, post-traumatic confusional state, or delirium. Recent guidelines suggest the importance of assessment and consistent management during this phase, but current practice worldwide remains unknown. This survey aimed to elucidate current international practice in assessment and treatment of patients in the acute stages of recovery after TBI. The web-based survey was distributed to clinicians working with patients with acute TBI. There were 400 participants (68.8% females), from 41 countries, mostly neuropsychologists, rehabilitation physicians, and occupational therapists (OTs), with an average 12.8 years of experience. Of those working with adults (n = 376, 94%), most described this acute period as post-traumatic amnesia and used its duration to indicate injury severity. More than 85% used a tool to assess patients; in order of frequency, the Glasgow Coma Scale (GCS), Westmead PTA Scale (WPTAS), Galveston Orientation and Amnesia Test, Rancho Los Amigos Scale, and O-Log. Meeting criteria on the assessment tool or clinical judgment determined emergence from this phase, indicated by recovery of orientation, day-to-day memories, and ability to follow commands or participate in rehabilitation. Most patients had physiotherapy, OT, speech therapy, and environmental changes, with a third of participants indicating sedating medication was prescribed during this phase. Findings suggest that, consistent with guidelines, PTA is a widely recognized and measured TBI recovery phase, used to determine injury severity and readiness for therapy.

Functional Change from Five to Fifteen Years after Traumatic Brain Injury

Few studies have assessed the long-term functional outcomes of traumatic brain injury (TBI) in large, well-characterized samples. Using the Traumatic Brain Injury Model Systems cohort, this study assessed the maintenance of independence between years 5 and 15 post-injury and risk factors for decline. The study sample included 1381 persons with TBI who received inpatient rehabilitation, survived to 15 years post-injury, and were available for data collection at 5 or 10 years and 15 years post-injury. The Functional Independence Measure (FIM) and Disability Rating Scale (DRS) were used to measure functional outcomes. The majority of participants had no changes during the 10-year time frame. For FIM, only 4.4% showed decline in Self-Care, 4.9% declined in Mobility, and 5.9% declined in Cognition. Overall, 10.4% showed decline in one or more FIM subscales. Decline was detected by DRS Level of Function (24% with >1-point change) and Employability (6% with >1-point change). Predictors of decline factors across all measures were age >25 years and, across most measures, having less than or equal to a high school education. Additional predictors of FIM decline included male sex (FIM Mobility and Self-Care) and longer rehabilitation length of stay (FIM Mobility and Cognition). In contrast to studies reporting change in the first 5 years post-TBI inpatient rehabilitation, a majority of those who survive to 15 years do not experience functional decline. Aging and cognitive reserve appear to be more important drivers of loss of function than original severity of the injury. Interventions to identify those at risk for decline may be needed to maintain or enhance functional status as persons age with a TBI.

Two Coarse Spatial Patterns of Altered Brain Microstructure Predict Post-traumatic Amnesia in the Subacute Stage of Severe Traumatic Brain Injury

Introduction: Diffuse traumatic axonal injury (TAI) is one of the key mechanisms leading to impaired consciousness after severe traumatic brain injury (TBI). In addition, preferential regional expression of TAI in the brain may also influence clinical outcome. Aim: We addressed the question whether the regional expression of microstructural changes as revealed by whole-brain diffusion tensor imaging (DTI) in the subacute stage after severe TBI may predict the duration of post-traumatic amnesia (PTA). Method: Fourteen patients underwent whole-brain DTI in the subacute stage after severe TBI. Mean fractional anisotropy (FA) and mean diffusivity (MD) were calculated for five bilateral brain regions: fronto-temporal, parieto-occipital, and midsagittal hemispheric white matter, as well as brainstem and basal ganglia. Region-specific calculation of mean FA and MD only considered voxels that showed no tissue damage, using an exclusive mask with all voxels that belonged to local brain lesions or microbleeds. Mean FA or MD of the five brain regions were entered in separate partial least squares (PLS) regression analyses to identify patterns of regional microstructural changes that account for inter-individual variations in PTA. Results: For FA, PLS analysis revealed two spatial patterns that significantly correlated with individual PTA. The lower the mean FA values in all five brain regions, the longer that PTA lasted. A pattern characterized by lower FA values in the deeper brain regions relative to the FA values in the hemispheric regions also correlated with longer PTA. Similar trends were found for MD, but opposite in sign. The spatial FA changes as revealed by PLS components predicted the duration of PTA. Individual PTA duration, as predicted by a leave-one-out cross-validation analysis, correlated with true PTA values (Spearman r = 0.68, p permutation = 0.008). Conclusion: Two coarse spatial patterns of microstructural damage, indexed as reduction in FA, were relevant to recovery of consciousness after TBI. One pattern expressed was consistent with diffuse microstructural damage across the entire brain. A second pattern was indicative of a preferential damage of deep midline brain structures.

Concordance between current American Academy of Sleep Medicine and Centers for Medicare and Medicare scoring criteria for obstructive sleep apnea in hospitalized persons with traumatic brain injury: a VA TBI Model System study

STUDY OBJECTIVES

The objective of this study was to compare obstructive sleep apnea (OSA), demographic, and traumatic brain injury (TBI) characteristics across the American Academy of Sleep Medicine (AASM) and Centers for Medicare and Medicare (CMS) scoring rules in moderate to severe TBI undergoing inpatient neurorehabilitation.

METHODS

This is a secondary analysis from a prospective clinical trial of sleep apnea at 6 TBI Model System study sites (n = 248). Scoring was completed by a centralized center using both the AASM and CMS criteria for OSA. Hospitalization and injury characteristics were abstracted from the medical record, and demographics were obtained by interview by trained research assistants using TBI Model System standard procedures.

RESULTS

OSA was prevalent using the AASM (66%) and CMS (41.5%) criteria with moderate to strong agreement (weighted κ = 0.64; 95% confidence interval = 0.58-0.70). Significant differences were observed for participants meeting AASM and CMS criteria (concordant group) compared with those meeting criteria for AASM but not CMS (discordant group). At an apnea-hypopnea index ≥ 5 events/h, the discordant group (n = 61) had lower Emergency Department Glasgow Coma Scale Scores consistent with greater injury severity (median, 5 vs 13; P = .0050), younger age (median, 38 vs 58; P < .0001), and lower body mass index (median, 22.1 vs 24.8; P = .0007) compared with the concordant group (n = 103). At an apnea-hypopnea index ≥ 15 events/h, female sex but no other differences were noted, possibly because of the smaller sample size.

CONCLUSIONS

The underestimation of sleep apnea using CMS criteria is consistent with prior literature; however, this is the first study to report the impact of the criteria in persons with moderate to severe TBI during a critical stage of neural recovery. Management of comorbidities in TBI has become an increasing focus for optimizing TBI outcomes. Given the chronic morbidity after moderate to severe TBI, the impact of CMS policy for OSA diagnosis for persons with chronic disability and young age are considerable.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Comparison of Sleep Apnea Assessment Strategies to Maximize TBI Rehabilitation Participation and Outcome; Identifier: NCT03033901.

Sleep spindles are resilient to extensive white matter deterioration

Sleep spindles are an essential part of non-rapid eye movement sleep, notably involved in sleep consolidation, cognition, learning and memory. These oscillatory waves depend on an interaction loop between the thalamus and the cortex, which relies on a structural backbone of thalamo-cortical white matter tracts. It is still largely unknown if the brain can properly produce sleep spindles when it underwent extensive white matter deterioration in these tracts, and we hypothesized that it would affect sleep spindle generation and morphology. We tested this hypothesis with chronic moderate to severe traumatic brain injury (n = 23; 30.5 ± 11.1 years old; 17 m/6f), a unique human model of extensive white matter deterioration, and a healthy control group (n = 27; 30.3 ± 13.4 years old; 21m/6f). Sleep spindles were analysed on a full night of polysomnography over the frontal, central and parietal brain regions, and we measured their density, morphology and sigma-band power. White matter deterioration was quantified using diffusion-weighted MRI, with which we performed both whole-brain voxel-wise analysis (Tract-Based Spatial Statistics) and probabilistic tractography (with High Angular Resolution Diffusion Imaging) to target the thalamo-cortical tracts. Group differences were assessed for all variables and correlations were performed separately in each group, corrected for age and multiple comparisons. Surprisingly, although extensive white matter damage across the brain including all thalamo-cortical tracts was evident in the brain-injured group, sleep spindles remained completely undisrupted when compared to a healthy control group. In addition, almost all sleep spindle characteristics were not associated with the degree of white matter deterioration in the brain-injured group, except that more white matter deterioration correlated with lower spindle frequency over the frontal regions. This study highlights the resilience of sleep spindles to the deterioration of all white matter tracts critical to their existence, as they conserve normal density during non-rapid eye movement sleep with mostly unaltered morphology. We show that even with such a severe traumatic event, the brain has the ability to adapt or to withstand alterations in order to conserve normal sleep spindles.

Epilepsy after severe traumatic brain injury: frequency and injury severity

Objective: To estimate national frequency of posttraumatic epilepsy (PTE) after severe traumatic brain injury (TBI) and assess injury severity (Glasgow Coma Scale (GCS) and posttraumatic amnesia (PTA)) as prognostic factors for PTE.

METHODS

Data on patients ≥18 years surviving severe TBI 2004-2016 were retrieved from the Danish Head Trauma Database (n = 1010). The cumulative incidence proportion (CIP) was estimated using death as competing event. The association between injury severity and PTE was assessed using multivariable competing risk regressions.

RESULTS

CIP of PTE 28 days and one year post-TBI was 6.8% (95% confidence interval (CI) 5.4-8.5) and 18.5% (95% CI 16.1-21.1%), respectively. Injury severity was not associated with PTE within 28 days post-TBI but indicated higher PTE-rates in less severely injured patients. PTA-duration >70 days was associated with PTE 29-365 days post-TBI (Adjusted sub-hazard ratio 4.23 (95% CI 1.79-9.99)). GCS was not associated with PTE 29-365 days post-TBI.

CONCLUSION

The PTE frequency was higher compared to previous estimates. Increasing injury severity was associated with PTE 29-365 days post-TBI when measured with PTA, but not with GCS. Though nonsignificant, the increased PTE-risk within 28 days in lower severity suggests an underdiagnosing of PTE.

Comparison of Diagnostic Sleep Studies in Hospitalized Neurorehabilitation Patients With Moderate to Severe Traumatic Brain Injury

BACKGROUND

OSA is prevalent during a time of critical neural repair after traumatic brain injury (TBI). The diagnostic utility of existing sleep studies is needed to inform clinical management during acute recovery from TBI.

RESEARCH QUESTION

This study aimed to evaluate the non-inferiority and diagnostic accuracy of a portable level 3 sleep study relative to level 1 polysomnography in hospitalized neurorehabilitation patients with TBI.

STUDY DESIGN AND METHODS

This is a prospective clinical trial conducted at six TBI Model System study sites between May 2017 and February 2019. Of 896 admissions, 449 were screened and eligible for the trial, with 345 consented. Additional screening left 263 eligible for and completing simultaneous administration of both level 1 and level 3 sleep studies, with final analyses completed on 214 (median age = 42 years; ED Glasgow Coma Scale = 6; time to polysomnography [PSG] = 52 days).

RESULTS

Agreement was moderate to strong (weighted kappa = 0.78, 95% CI, 0.72-0.83) with the misclassification commonly occurring with mild sleep apnea due to underestimation of apnea hypopnea index (AHI). Most of those with moderate to severe sleep apnea were correctly classified (n = 54/72). Non-inferiority was not demonstrated: the minimum tolerable specificity of 0.5 was achieved across all AHI cutoff scores (lower confidence limits [LCL] range, 0.807-0.943), but the minimum tolerable sensitivity of 0.8 was not (LCL range, 0.665-0.764).

INTERPRETATION

Although the non-inferiority of level 3 portable diagnostic testing relative to level 1 was not established, strong agreement was seen across sleep apnea indexes. Most of those with moderate to severe sleep apnea were correctly identified; however, there was risk of misclassification with level 3 sleep studies underestimating disease severity for those with moderate to severe AHI and disease presence for those with mild AHI during early TBI neurorehabilitation.

Relationship Between Hispanic Nativity, Residential Environment, and Productive Activity Among Individuals With Traumatic Brain Injury: A TBI Model Systems Study

OBJECTIVE

To examine the influence of nativity and residential characteristics on productive activity among Hispanics at 1 year after traumatic brain injury (TBI).

SETTING

Acute rehabilitation facilities and community follow-up.

PARTICIPANTS

A total of 706 Hispanic individuals in the TBI Model Systems National Database.

DESIGN

Secondary data analysis from a multicenter longitudinal cohort study.

MAIN MEASURES

Nativity (foreign born or US native), productive activity derived from interview questions regarding employment status, and other demographic information. Census data were extracted by zip code to represent residential characteristics of aggregate household income and proportion of foreign language speakers (FLS).

RESULTS

Among foreign-born individuals with TBI, those living in an area with a higher proportion of FLS were 2.8 times more likely to be productive than those living in areas with a lower proportion of FLS. Among individuals living in an area with a lower proportion of FLS, US-born Hispanics were 2.7 times more likely to be productive compared with Hispanic immigrants.

CONCLUSION

The relationship between nativity and productive activity at 1 year post-TBI was moderated by the residential proportion of FLS. Findings underscore the importance of considering environmental factors when designing vocational rehabilitation interventions for Hispanics after TBI.

Retrograde Autobiographical Memory From PTA Emergence to Six-Month Follow-Up in Moderate to Severe Traumatic Brain Injury

OBJECTIVE

The overwhelming focus of research on memory following traumatic brain injury (TBI) has been on anterograde amnesia, and very little attention has been paid to retrograde amnesia. There is evidence to suggest that retrograde autobiographical memory deficits exist after severe TBI, although there have been no prospective studies of autobiographical memory in a representative sample of moderate to severe cases recruited from hospital admissions.

METHODS

The purpose of the present study was to report changes in autobiographical memory performance among a group of patients soon after emergence from posttraumatic amnesia (PTA) and at the 6-month follow-up compared with a healthy control (HC) group. The authors also examined associations with anterograde memory function and community integration to assist in understanding the functional impact of autobiographical memory deficits and potential underlying mechanisms. The Autobiographical Memory Interview and the Rey Auditory Verbal Learning Test were used as measures of retrograde and anterograde memory, respectively, and the Community Integration Questionnaire was used as a measure of functional outcome in the TBI group.

RESULTS

The results demonstrated that both personal semantic and episodic autobiographical memory scores were impaired following emergence from PTA and at the 6-month follow-up. Only subtle differences emerged in change over time in different injury severity groups. Recent retrograde memory function was associated with anterograde memory performance, which supports some degree of overlap in underlying mechanisms.

CONCLUSIONS

The findings suggest that autobiographical memory deficits are prevalent following moderate to severe TBI and warrant consideration in rehabilitation.

Race/Ethnicity and Retention in Traumatic Brain Injury Outcomes Research: A Traumatic Brain Injury Model Systems National Database Study

OBJECTIVE

To investigate the contribution of race/ethnicity to retention in traumatic brain injury (TBI) research at 1 to 2 years postinjury.

SETTING

Community.

PARTICIPANTS

With dates of injury between October 1, 2002, and March 31, 2013, 5548 whites, 1347 blacks, and 790 Hispanics enrolled in the Traumatic Brain Injury Model Systems National Database.

DESIGN

Retrospective database analysis.

MAIN MEASURE

Retention, defined as completion of at least 1 question on the follow-up interview by the person with TBI or a proxy.

RESULTS

Retention rates 1 to 2 years post-TBI were significantly lower for Hispanic (85.2%) than for white (91.8%) or black participants (90.5%) and depended significantly on history of problem drug or alcohol use. Other variables associated with low retention included older age, lower education, violent cause of injury, and discharge to an institution versus private residence.

CONCLUSIONS

The findings emphasize the importance of investigating retention rates separately for blacks and Hispanics rather than combining them or grouping either with other races or ethnicities. The results also suggest the need for implementing procedures to increase retention of Hispanics in longitudinal TBI research.

Employment Stability in the First 5 Years After Moderate-to-Severe Traumatic Brain Injury

OBJECTIVE

To characterize employment stability and identify predictive factors of employment stability in working-age individuals after moderate-to-severe traumatic brain injury (TBI) that may be clinically addressed.

DESIGN

Longitudinal observational study of an inception cohort from the Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) using data at years 1, 2, and 5 post-TBI.

SETTING

Inpatient rehabilitation centers with telephone follow-up.

PARTICIPANTS

Individuals enrolled in the TBIMS-NDB since 2001, aged 18-59, with employment data at 2 or more follow-up interviews at years 1, 2, and 5 (N=5683).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Employment stability, categorized using post-TBI employment data as no paid employment (53.25%), stably (27.20%), delayed (10.24%), or unstably (9.31%) employed.

RESULTS

Multinomial regression analyses identified predictive factors of employment stability, including younger age, white race, less severe injuries, preinjury employment, higher annual earnings, male sex, higher education, transportation independence postinjury, and no anxiety or depression at 1 year post-TBI.

CONCLUSIONS

Employment stability serves as an important measure of productivity post-TBI. Psychosocial, clinical, environmental, and demographic factors predict employment stability post-TBI. Notable predictors include transportation independence as well as the presence of anxiety and depression at year 1 post-TBI as potentially modifiable intervention targets.

Predictors of Satisfaction With Life in Veterans After Traumatic Brain Injury: A VA TBI Model Systems Study

OBJECTIVE

To identify predictors of satisfaction with life in Veterans 1 year after traumatic brain injury (TBI).

SETTING

The VA TBI Model Systems (TBIMS) project includes 5 Veterans Affairs (VA) Polytrauma Rehabilitation Centers.

PARTICIPANTS

Veterans enrolled in the VA TBIMS study who completed the Satisfaction With Life Scale at year 1 follow-up. The sample is largely male (96%) and Caucasian (72%), with a median age of 27 years upon enrollment.

DESIGN

Prospective observational cohort study measuring including demographics (eg, education), preinjury variables (eg, mental health history and employment), and military variables (eg, injury during deployment and injury during active duty status).

MAIN OUTCOME MEASURE

Satisfaction With Life Scale.

RESULTS

Multivariate regression analyses revealed that age, marital status, preinjury employment status, preinjury mental health history, and active duty status at the time of injury were significant predictors of life satisfaction at year 1 follow-up.

CONCLUSIONS

Results of this study suggest that satisfaction with life in Veterans with TBI is mediated by several factors that might inform rehabilitation interventions and discharge recommendations. Preinjury variables and active duty status (a unique aspect of the Veteran population) influence life satisfaction at 1 year postinjury. Limitations and future clinical implications will be discussed.

Community Reintegration Problems Among Veterans and Active Duty Service Members With Traumatic Brain Injury

OBJECTIVES

To examine community reintegration problems among Veterans and military service members with mild or moderate/severe traumatic brain injury (TBI) at 1 year postinjury and to identify unique predictors that may contribute to these difficulties.

SETTING

VA Polytrauma Rehabilitation Centers.

PARTICIPANTS

Participants were 154 inpatients enrolled in the VA TBI Model Systems Program with available injury severity data (mild = 28.6%; moderate/severe = 71.4%) and 1-year postinjury outcome data.

DESIGN

Prospective, longitudinal cohort.

MAIN MEASURES

Community reintegration outcomes included independent driving, employability, and general community participation. Additional measures assessed depression, posttraumatic stress, and cognitive and motor functioning.

RESULTS

In the mild TBI (mTBI) group, posttraumatic stress disorder and depressive symptoms were associated with lower levels of various community reintegration outcomes. In the moderate/severe TBI group, cognition and motor skills were significantly associated with lower levels of community participation, independent driving, and employability.

CONCLUSION

Community reintegration is problematic for Veterans and active duty service members with a history of TBI. Unique comorbidities across injury severity groups inhibit full reintegration into the community. These findings highlight the ongoing rehabilitation needs of persons with TBI, specifically evidence-based mental healthcare, in comprehensive rehabilitation programs consistent with a chronic disease management model.

Incidence, Characterization, and Predictors of Sleep Apnea in Consecutive Brain Injury Rehabilitation Admissions

OBJECTIVE

To prospectively examine the incidence and risk factors for sleep apnea in consecutive brain injury rehabilitation admissions.

SETTING

Inpatient neurorehabilitation hospital.

PARTICIPANTS

Participants (n = 86) were consecutive neurorehabilitation admissions.

DESIGN

Retrospective analysis of prospectively collected data.

MAIN MEASURES

Polysomnography.

RESULTS

Half (49%) of the sample was diagnosed with sleep apnea. For the full sample, univariate logistic regression revealed age (odds ratio: 1.08; 95% confidence interval: 1.04-1.11) and hypertension (odds ratio: 7.77; 95% confidence interval: 2.81-21.47) as significant predictors of sleep apnea diagnosis. Results of logistic regression conducted within the traumatic brain injury group revealed age (odds ratio: 1.07; 95% confidence interval: 1.02-1.13) as the only significant predictor of apnea diagnosis after adjustment for other variables. Hierarchical generalized linear regression models for the prediction of apnea severity (ie, apnea-hypopnea index found that Functional Independence Measure Cognition Score (P = .01) and age (P < .01) were significant predictors. Following adjustment for all other terms, only age (P < .01) remained significant.

CONCLUSION

Sleep apnea is prevalent in acute neurorehabilitation admissions and traditional risk profiles for sleep apnea may not effectively screen for the disorder. Given the progressive nature of obstructive sleep apnea and morbidity associated with even mild obstructive sleep apnea, early identification and intervention may address comorbidities influencing acute and long-term outcome.

Correlations between Cognitive Impairments and Employment Status in Patients with Diffuse Axonal Injury

Patients with diffuse axonal injury (DAI) may initially present with prominent physical impairments, but their cognitive dysfunctions are more persistent and are attributable to later unemployment. In this study, we analyzed how the findings of early and delayed neuropsychological assessments correlated with employment outcome of patients with DAI. A total of 56 patients with DAI without motor or visual dysfunction were included in this study. The neuropsychological battery consisted of the Wechsler Adult Intelligent Scale - Revised (WAIS-R), Wechsler Memory Scale - Revised (WMS-R), Trail Making Test (TMT), Wisconsin Card Sorting Test (WCST), and Word Fluency Test (WFT). This battery of tests was administered twice in early stage after injury and in later stage. The results of all of the neuropsychological tests improved significantly (P <0.001) between the early and later assessments. All scores other than TMT part A and B improved to the normal range (Z-score ≥ 2). The patient characteristics (age, gender, initial Glasgow Coma Scale, and duration of posttraumatic amnesia) had no relationship to the outcome. The results of TMT part B, however, were significantly correlated with employment outcome in both the early and later assessments (P = 0.01, 0.04). Given that TMT evaluates visual attention, we surmise that a lack of attention may be the core symptom of the cognitive deficit and cause the re-employment failure in patients with DAI. TMT part B in both early and later assessments has the potential to accurately predict chronic functional outcome.

Post-traumatic amnesia and confusional state: hazards of retrospective assessment

Retrospective assessment of post-traumatic amnesia (PTA) must take into account factors other than traumatic brain injury (TBI) which may impact on memory both at the time of injury and subsequent to the injury. These include analgesics, anaesthesia required for surgery, and the development of acute or post-traumatic stress disorder. This is relevant in clinical and medicolegal settings. Repeated assessments of the post-injury state, involving tests for continuing amnesia, risk promoting recall of events suggested by the examiner, or generating confabulations. The PTA syndrome affects the categorical autobiographical memory, and is accompanied by confusion as an essential component; this should be suspected from the initial or early Glasgow Coma Scale score (13-14/15) if not directly recorded by clinical staff. PTA by itself is only one of several indices of severity of TBI. The nature of the head injury, including observers' accounts, clinical and neuroimaging data, the possible role of other external injuries, blood loss, acute stress disorder and the potential for hypoxic brain injury, must be taken into account as well as concomitant alcohol or substance abuse, and systemic shock. A plausible mechanism for a TBI must be demonstrable, and other causes of amnesia excluded.

Exploring Vocational Evaluation Practices following Traumatic Brain Injury

BACKGROUND

Individuals with traumatic brain injury (TBI) face many challenges when attempting to return to work (RTW). Vocational evaluation (VE) is a systematic process that involves assessment and appraisal of an individual's current work-related characteristics and abilities.

OBJECTIVE

The aims of this study are to (1) examine demographic and employment characteristics of vocational rehabilitation providers (VRPs), (2) identify the specific evaluation methods that are used in the VE of individuals with TBI, and (3) examine the differences in assessment method practices based upon evaluator assessment preferences.

METHODS

This exploratory case study used a forty-six-item online survey which was distributed to VRPs.

RESULTS

One hundred and nine VRPs accessed the survey. Of these, 74 completed the survey. A majority of respondents were female (79.7%), Caucasian (71.6%), and holding a master's degree (74.3%), and more than half (56.8%) were employed as state vocational rehabilitation counselors (VRCs). In addition, over two-thirds (67.6%) were certified rehabilitation counselors (CRCs). Respondents reported using several specific tools and assessments during the VE process.

CONCLUSIONS

Study findings reveal differences in use of and rationales for specific assessments amongst VRPs. Understanding VRP assessment practices and use of an evidence-based framework for VE following TBI may inform and improve VE practice.

Insomnia symptoms and behavioural health symptoms in veterans 1 year after traumatic brain injury

OBJECTIVE

Insomnia and behavioural health symptoms 1 year after traumatic brain injury (TBI) were examined in a clinical sample representative of veterans who received inpatient treatment for TBI-related issues within the Veterans Health Administration.

METHODS

This was a cross-sectional sub-study (n = 112) of the Polytrauma Rehabilitation Centres' traumatic brain injury model system programme. Prevalence estimates of insomnia, depression, general anxiety, nightmares, headache and substance use, stratified by injury severity, were derived. Univariate logistic regression was used to examine unadjusted effects for each behavioural health problem and insomnia by injury severity.

RESULTS

Participants were primarily male, < 30 years old and high school educated. Twenty-nine per cent met study criteria for insomnia; those with mild TBI were significantly more likely to meet criteria (43%) than those with moderate/severe TBI (22%), χ(2)(1, n = 112) = 5.088, p ≤ 0.05. Univariable logistic regression analyses revealed depressive symptoms and general anxiety were significantly associated with insomnia symptoms after TBI of any severity. Headache and binge drinking were significantly inversely related to insomnia symptoms after moderate/severe TBI, but not MTBI.

CONCLUSIONS

Veterans with history of TBI, of any severity, and current insomnia symptoms may be at increased risk for depression and anxiety 1 year after TBI.

Surviving severe traumatic brain injury in Denmark: incidence and predictors of highly specialized rehabilitation

PURPOSE

To identify all hospitalized patients surviving severe traumatic brain injury (TBI) in Denmark and to compare these patients to TBI patients admitted to highly specialized rehabilitation (HS-rehabilitation).

PATIENTS AND METHODS

Patients surviving severe TBI were identified from The Danish National Patient Registry and The Danish Head Trauma Database. Overall incidence rates of surviving severe TBI and incidence rates of admission to HS-rehabilitation after severe TBI were estimated and compared. Patient-related predictors of no admission to HS-rehabilitation among patients surviving severe TBI were identified using multivariable logistic regression.

RESULTS

The average incidence rate of surviving severe TBI was 2.3 per 100,000 person years. Incidence rates of HS-rehabilitation were generally stable around 2.0 per 100,000 person years. Overall, 84% of all patients surviving severe TBI were admitted to HS-rehabilitation. Female sex, older age, and non-working status pre-injury were independent predictors of no HS-rehabilitation among patients surviving severe TBI.

CONCLUSION

The incidence rate of hospitalized patients surviving severe TBI was stable in Denmark and the majority of the patients were admitted to HS-rehabilitation. However, potential inequity in access to HS-rehabilitation may still be present despite a health care system based on equal access for all citizens.

High-level mobility in chronic traumatic brain injury and its relationship with clinical variables and magnetic resonance imaging findings in the acute phase

OBJECTIVES

To compare high-level mobility in individuals with chronic moderate-to-severe traumatic brain injury (TBI) with matched healthy controls, and to investigate whether clinical variables and magnetic resonance imaging (MRI) findings in the acute phase can predict high-level motor performance in the chronic phase.

DESIGN

A longitudinal follow-up study.

SETTING

A level 1 trauma center.

PARTICIPANTS

Individuals (N=136) with chronic TBI (n=65) and healthy matched peers (n=71).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

High-Level Mobility Assessment Tool (HiMAT) and the revised version of the HiMAT performed at a mean of 2.8 years (range, 1.5-5.4y) after injury.

RESULTS

Participants with chronic TBI had a mean HiMAT score of 42.7 (95% confidence interval [CI], 40.2-45.2) compared with 47.7 (95% CI, 46.1-49.2) in the control group (P<.01). Group differences were also evident using the revised HiMAT (P<.01). Acute-phase clinical variables and MRI findings explained 58.8% of the variance in the HiMAT score (P<.001) and 59.9% in the revised HiMAT score (P<.001). Lower HiMAT scores were associated with female sex (P=.031), higher age at injury (P<.001), motor vehicle collisions (P=.030), and posttraumatic amnesia >7 days (P=.048). There was a tendency toward an association between lower scores and diffuse axonal injury in the brainstem (P=.075).

CONCLUSIONS

High-level mobility was reduced in participants with chronic, either moderate or severe TBI compared with matched peers. Clinical variables in the acute phase were significantly associated with high-level mobility performance in participants with TBI, but the role of early MRI findings needs to be further investigated. The findings of this study suggest that the clinical variables in the acute phase may be useful in predicting high-level mobility outcome in the chronic phase.

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.

The differential contributions of posttraumatic amnesia duration and time since injury in prediction of functional outcomes following moderate-to-severe traumatic brain injury

OBJECTIVE

To examine the relative contributions of preinjury, injury severity, and acute postinjury variables in predicting outcomes at 1 year following moderate-severe traumatic brain injury (TBI).

DESIGN

Secondary analysis of a prospective longitudinal cohort study.

SETTING

Four Veterans Affairs Medical Center acute inpatient rehabilitation programs.

PARTICIPANTS

Active duty military or veterans with a nonpenetrating moderate-to-severe TBI.

MAIN OUTCOME MEASURES

Independent living status (N = 280) and work status (N = 248) at one year postinjury.

RESULTS

Preinjury characteristics as a group accounted for the largest amount of variance in independent living status at 1 year; however, posttraumatic amnesia (PTA) uniquely explained the largest amount of variance (8.8%). Those with less than 60 days PTA were 9 times more likely to be independent; those with less than 30 days PTA were 3 times more likely to be independent. In contrast, acute postinjury characteristics accounted for the largest amount of variance in work status, with time to rehabilitation explaining the most unique variance (10.4%). Those with less than 48 days time to rehabilitation were 2.4 times more likely to be productive.

CONCLUSIONS

This study highlights the differential contribution of variables in the prediction of 2 specific functional outcomes in a military sample, adding to our current body of knowledge to assist clinicians, patients and their families following TBI.

Mortality after surviving traumatic brain injury: risks based on age groups

OBJECTIVE

To assess mortality, life expectancy, risk factors, and causes of death by age groups among persons who received inpatient traumatic brain injury (TBI) rehabilitation.

DESIGN

Prospective cohort study.

SETTING

The TBI Model Systems.

PARTICIPANTS

8573 individuals injured between 1988 and 2009, with survival status per December 31, 2009, determined.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Standardized mortality ratio, life expectancy, and cause of death.

RESULTS

Moderate-severe TBI increases risk of mortality compared with the general population in all age groups, with the exception of those 85 years or older at the time of injury. Teenagers to middle-aged adults are at particular risk. Risk factors for death varied by age group and included gender, marital and employment status, year and cause of injury, and level of disability. External causes of death predominate in younger groups. For the youngest male participants in the sample, longevity was reduced up to 16 years.

CONCLUSION

Risk factors and causes of death varied considerably by age group for individuals with moderate-severe TBI who were receiving acute care rehabilitation. Moderate-severe TBI is a chronic health condition.

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.

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.

Validity of Movement Pattern Kinematics as Measures of Arm Motor Impairment Poststroke

Background and Purpose— Upper limb motor impairment poststroke is commonly evaluated using clinical outcome measures such as the Fugl-Meyer Assessment. However, most clinical measures provide little information about motor patterns and compensations (eg, trunk displacement) used for task performance. Such information is obtained using movement quality kinematic variables (joint ranges, trunk displacement). Evaluation of movement quality may also help distinguish between levels of motor impairment severity in individuals poststroke. Our objective was to estimate concurrent and discriminant validity of movement quality kinematic variables for pointing and reach-to-grasp tasks.

Methods— A retrospective study of kinematic data (sagittal trunk displacement, shoulder flexion, shoulder horizontal adduction, elbow extension) and Fugl-Meyer Assessment scores from 86 subjects (subacute to chronic stroke) performing pointing and reaching tasks was done. Multiple and logistic regression analyses were used to estimate concurrent and discriminant validity respectively. Cutoff points for distinguishing between levels of upper limb motor impairment severity (mild, moderate to severe) were estimated using sensitivity/specificity decision plots. The criterion measure used was the Fugl-Meyer Assessment (upper limb section).

Results— The majority of variance in Fugl-Meyer Assessment scores was explained by a combination of trunk displacement and shoulder flexion (51%) for the pointing task and by trunk displacement alone (52%) for the reach-to-grasp task. Trunk displacement was the only variable that distinguished between levels of motor impairment severity. Cutoff points were 4.8 cm for pointing and 10.2 cm for reach-to-grasp movements.

Conclusion— Movement quality kinematic variables are valid measures of arm motor impairment levels poststroke. Their use in regular clinical practice and research is justified.