Self-reported changes to nighttime sleep after traumatic brain injury

OBJECTIVES: To explore subjective sleep reports from people in the chronic stages of traumatic brain injury (TBI) and to examine the extent and nature of sleep complaints in this population. DESIGN: Survey. SETTING: All participants were community based at the time of data collection. PARTICIPANTS: Sixty-three subjects with TBI consecutively recruited after discharge from rehabilitation and 63 age- and sex-matched controls from the general community. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: A 7-day self-reported sleep-wake diary assessing sleep and wake times, sleep onset latency, frequency, and duration of nocturnal awakenings and daytime naps; a general sleep questionnaire used to evaluate sleep changes and quality; and the Epworth Sleepiness Scale to measure daytime sleepiness. RESULTS: Group-wise comparisons showed a significantly higher frequency of reported sleep changes after TBI (80%) relative to the control group (23%), supporting previous findings. The TBI group reported more nighttime awakenings and longer sleep onset latency; these changes were more frequently reported by participants with TBI with milder injuries. Increased levels of anxiety and depression were associated with increased reporting of sleep changes. CONCLUSIONS: These findings confirm the experience of changes to sleep after TBI and may at least in part account for the reported increased daytime sleepiness in this population. Sleep disturbance should be addressed during rehabilitation. Treatments need to focus on correcting the underlying cause of the sleep problem and to address patients' subjective experiences of their sleep, possibly through education and mood stabilization.     

Headache after moderate and severe traumatic brain injury: a longitudinal analysis

OBJECTIVES: To measure longitudinally headache (HA) after moderate and severe traumatic brain injury (TBI) and to examine potential association with demographic, injury, and psychologic factors. DESIGN: Cohort study. SETTING: Four Veterans Administration rehabilitation facilities (Minneapolis, Palo Alto, Richmond, Tampa) within the Defense and Veterans Brain Injury Center. PARTICIPANTS: Consecutive patients (military or veteran beneficiaries) with moderate or severe TBI (N=109) who during acute rehabilitation consented to data collection and who completed 6- and 12-month follow-up evaluations. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: HA frequency, location, type, and incapacitation levels measured during prospective neurologic assessments. RESULTS: Nearly 38% (41/109) of patients had acute posttraumatic headache (PTHA) symptoms; most often in a frontal location (20/41), most often of daily frequency (31/41), and showing no relation to injury severity, emotional, or demographic variables. Postacutely, PTHA symptom severity declined within the group. Better individual improvement was associated with less anxiety and depression at 6-month follow-up. Almost all subjects (21/22) with PTHA symptoms that persisted into the 6-month follow-up period reported symptoms again at 12-month follow-up. CONCLUSIONS: PTHA severity in this sample of persons with moderate and severe TBI showed a pattern of improvement that leveled off by 6 months posthospitalization.     

Recovery of ambulation after traumatic brain injury

OBJECTIVES: To identify variables that are predictive of independent ambulation after traumatic brain injury (TBI) and to define the time course of recovery. DESIGN: Retrospective review of consecutive admissions of patients with severe TBI over a 32-month period. SETTING: Brain injury unit in an acute, inpatient rehabilitation hospital. PARTICIPANTS: Of 264 patients screened, 116 met criteria that included the ability to participate in motor and functional evaluation on admission to acute rehabilitation, and the absence of other neurologic disorders or fractures that affect one's ability to ambulate. INTERVENTION: Inpatient rehabilitation on a specialized TBI unit by an interdisciplinary team.Main outcome measures Recovery of independent ambulation and time to recover independent ambulation. RESULTS: Of eligible patients, 73.3% achieved independent ambulation by latest follow-up (up to 5.1 mo). Patients who achieved independent ambulation were significantly younger (P<.05), had better gait scores on admission (P<.05), and tended to be less severely injured-based on duration of posttraumatic amnesia (PTA; P=.058)-than those who did not ambulate independently. There were no differences in recovery based on neuropathologic profile. Mean time to independent ambulation +/- standard deviation was 5.7+/-4.3 weeks; of those achieving independent ambulation, 82.4% did so by 2 months and 94.1% by 3 months. If not independent by 3 months postinjury, patients had a 13.9% chance of recovery. Multivariate regression analysis generated prediction models for time to independent ambulation, using admission FIM instrument scores and age (38% of variance); initial gait score, loss of consciousness, and age (40% of variance); or initial gait score and PTA (58% of variance), when restricted to just those patients with diffuse axonal injury. CONCLUSIONS: Most patients with severe TBI achieved independent ambulation; the vast majority did so within 3 months postinjury. Functional measures, injury severity measures, and age can help guide prognosis and expectations for time to recover.     

Major and minor depression after traumatic brain injury

Hart T, Brenner L, Clark AN, Bogner JA, Novack TA, Chervoneva I, Nakase-Richardson R, Arango-Lasprilla JC. Major and minor depression after traumatic brain injury.

Objective

To examine minor as well as major depression at 1 year posttraumatic brain injury (TBI), with particular attention to the contribution of depression severity to levels of societal participation.

Design

Observational prospective study with a 2-wave longitudinal component.

Setting

Inpatient rehabilitation centers, with 1-year follow up conducted primarily by telephone.

Participants

Persons with TBI (N=1570) enrolled in the TBI Model System database and followed up at 1-year postinjury.

Interventions

Not applicable.

Main Outcome Measures

FIM, Patient Health Questionnaire-9, Participation Assessment with Recombined Tools-Objective, Glasgow Outcome Scale-Extended, and the Satisfaction With Life Scale.

Results

Twenty-two percent of the sample reported minor depression, and 26% reported major depression at 1-year post-TBI. Both levels of depression were associated with sex (women), age (younger), preinjury mental health treatment and substance abuse, and cause of injury (intentional). There was a monotonic dose-response relationship between severity of depression and all 1-year outcomes studied, including level of cognitive and physical disability, global outcome, and satisfaction with life. With other predictors controlled, depression severity remained significantly associated with the level of societal participation at 1-year post-TBI.

Conclusions

Minor depression may be as common as major depression after TBI and should be taken seriously for its association to negative outcomes related to participation and quality of life. Findings suggest that, as in other populations, minor and major depression are not separate entities, but exist on a continuum. Further research should determine whether people with TBI traverse between the 2 diagnoses as in other patient groups.     

A longitudinal study of health-related quality of life after traumatic brain injury

OBJECTIVE: To examine the longitudinal course of health-related quality of life from 1 month to 3 to 5 years after traumatic brain injury (TBI). DESIGN: Longitudinal cohort study with 4 evaluation points. SETTING: Level I trauma center. PARTICIPANTS: Consecutive hospital admissions of 133 adolescents and adults with complicated mild to severe TBI who completed the outcome measure at all 4 time points, 111 general trauma patients, and 87 healthy friend controls. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Sickness Impact Profile. RESULTS: TBI patients reported significant limitations at 1 month postinjury, with substantial improvement occurring by 6 months, especially in the physical domain. Psychosocial improvement was smaller, and perceived cognitive, emotional, and communication difficulties did not change over the time period assessed. Persons with TBI had clear difficulties relative to healthy peers, but their reported level of difficulties was very similar to that of the persons who had sustained a general trauma by 1 year postinjury. CONCLUSIONS: In this sample, TBI was associated with significant early limitations in most aspects of everyday life. Considerable improvement was noted over the first 6 months postinjury, especially in physical domains. Some aspects of psychosocial functioning also improved, although reported limitations in communication, cognitive, and emotional domains remained constant over time. These findings highlight the persistence of injury-related difficulties that compromise quality of life.     

Cognitive impairment in patients with traumatic brain injury and obstructive sleep apnea

OBJECTIVE: To examine the impact of comorbid obstructive sleep apnea (OSA) on the cognitive functioning of traumatic brain injury (TBI) patients. DESIGN: A case-control study. Neuropsychologic test performances of TBI patients with OSA were compared with those who did not have OSA. The diagnosis of OSA was based on standard criteria using nocturnal polysomnography. SETTING: Three academic medical centers with level I trauma centers, accredited sleep disorders centers, and rehabilitation medicine programs. PARTICIPANTS: Thirty-five TBI patients who were part of a project that assessed the effect of sleep disorders in a larger sample of consecutively recruited TBI patients. There were 19 patients with TBI and OSA. They were compared with 16 TBI patients without OSA who were comparable in terms of age, education, severity of injury (when available), time postinjury, and Glasgow Coma Scale scores (when available). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The Psychomotor Vigilance Test, Rey Complex Figure Test, Rey Auditory Verbal Learning Test, digit span test from the Wechsler Memory Scale-Revised, and finger-tapping test. RESULTS: The TBI patients with OSA performed significantly worse than the non-sleep disordered TBI patients on verbal and visual delayed-recall measures. The groups performed comparably on motor, visual construction, and attention tests. The TBI patients with OSA made more attention lapses (reaction times >/=500ms), but showed comparable fastest and slowest reaction times on a measure of sustained attention. CONCLUSIONS: OSA is associated with more impairment of sustained attention and memory in TBI patients. It is possible that early identification and treatment of OSA may improve cognitive, and thus potentially functional, outcomes of TBI patients with this disease.     

Natural history of depression in traumatic brain injury

OBJECTIVE: To examine prospectively the rates, risk factors, and phenomenology of depression over 3 to 5 years after traumatic brain injury (TBI). DESIGN: Inception cohort longitudinal study. SETTING: Level I trauma center. PARTICIPANTS: Consecutive admissions of 283 adults with moderate to severe TBI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Center for Epidemiologic Studies Depression (CES-D) Scale. RESULTS: The rates of moderate to severe depression ranged from 31% at 1 month to 17% at 3 to 5 years. With 1 exception, the relation between brain injury severity and depression was negligible. Less than high school education, preinjury unstable work history, and alcohol abuse predicted depression after injury. Examination of CES-D factors indicate that, in addition to somatic symptoms, both depressed affect and lack of positive affect contribute to elevated CES-D scores. CONCLUSIONS: High rates of depressive symptoms cannot be dismissed on grounds that somatic symptoms related to brain injury are mistaken for depression. Depressed affect and lack of positive affect are also elevated in persons with TBI. Preinjury psychosocial factors are predictive of depression and knowing them should facilitate efforts to detect, prevent, and treat depression after TBI.     

Driving and community integration after traumatic brain injury

Rapport LJ, Coleman Bryer R, Hanks RA. Driving and community integration after traumatic brain injury.

Objective

To examine resumption of driving after traumatic brain injury (TBI) and its relation to community integration.

Design

Cross-sectional cohort study; survey and cognitive data.

Settings

Inpatient rehabilitation hospital of the Traumatic Brain Injury Model Systems and community.

Participants

Persons (N=261) ranging from 3 months to 15 years postinjury.

Interventions

Not applicable.

Main Outcome Measures

Barriers to Driving Questionnaire, Driver Survey, Community Integration Measure, and Craig Hospital Assessment and Reporting Technique.

Results

Forty-four percent of survivors had resumed driving; of nondrivers, 48% reported a strong desire to resume driving. Nondriver survivors who sought to resume driving generally rated themselves as currently fit to drive, viewed themselves as having physical and cognitive profiles like those of survivor drivers, and reported their greatest barriers to driving as social and resource related. However, cognitive functioning was similar to nondriver survivors who did not seek to resume driving and significantly worse than survivors who were currently driving. Nondrivers showed poorer community integration than did drivers, even after accounting for injury severity, social support, negative affectivity, and use of alternative transportation. Use of alternative transportation was common among nondrivers, but it was unrelated to community integration outcomes. Cognitive functioning moderated risk of adverse incident: among survivors with low cognitive functioning and high self-estimates of driving ability, which is indicative of unawareness of deficit, adverse incidents showed positive relation to amount of driving and inverse relation to cognitive functioning.

Conclusions

Driving status has unique and independent association with post-TBI community integration. Additional research is needed to evaluate transportation barriers that undermine full engagement in community living after TBI and to determine which barriers to driving reflect valid risk to survivors and the public.     

Outcome after traumatic brain injury: effects of aging on recovery

OBJECTIVE: To identify differences in outcome after traumatic brain injury (TBI) compared with orthopedic injuries as a function of age. DESIGN: Longitudinal data analyses from an inception cohort. SETTING: Outpatient rehabilitation program. PARTICIPANTS: Eighty-two orthopedic injury patients and 195 TBI patients. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Independent living, employment, and level of functioning 1 to 2 years after injury. RESULTS: Older patients and those with TBI were more likely to have increased dependence postinjury. Older TBI patients were more likely to have changes in employment status compared with orthopedic injury patients younger or TBI. The Mayo-Portland Adaptability Inventory and Disability Rating Scale were moderately predictive of level of functioning, return to employment, and independent living status 1 to 2 years postinjury. Injury severity was only mildly predictive of outcome. CONCLUSIONS: The effect of age on outcome affects recovery from neurologic injuries and, to a lesser extent, orthopedic injuries. Outcome after TBI is best predicted by patients' age and estimates of level of function at discharge. Findings suggest that older patients and those with TBI have a greater likelihood of becoming physically and financially dependent on others. Rehabilitation efforts should focus on maximizing levels of independence to limit financial and emotional costs to patients and their families.     

Occupational categories and return to work after traumatic brain injury: a multicenter study

OBJECTIVE: To further evaluate determinants of return to work (RTW) after traumatic brain injury (TBI), with focus on the relation between preinjury occupational category and RTW outcome. DESIGN: Prospective collaborative cohort study. SETTING: Seventeen National Institute on Disability and Rehabilitation Research-designated Traumatic Brain Injury Model Systems. PARTICIPANTS: Consecutive sample of 1341 patients (age range, 18-62y) who were hospitalized with a TBI diagnosis, received both acute neurotrauma services and inpatient rehabilitation services, consented to participate, were employed before injury, and completed a 1-year follow-up assessment. INTERVENTION: An inpatient interdisciplinary brain injury rehabilitation program. MAIN OUTCOME MEASURE: Competitive employment at 1 year postinjury. RESULTS: Participants were categorized into 1 of 3 groups depending on preinjury occupational title: professional/managerial (n=192), skilled (n=751), or manual labor (n=398). Chi-square analyses were computed to examine changes across occupation groups between preinjury occupation group and postinjury RTW. The rate of successful RTW was greatest for professional/managerial (56%), lower for skilled (40%), and lowest for manual labor (32%), yielding an odds ratio of 2.959 between the highest and lowest groups. Of those with successful RTW, most did so within the same occupational category grouping. A multiple logistic regression showed that preinjury occupation, education level, discharge FIM score, age, sex, marital status, and hospital length of stay each influenced RTW. CONCLUSIONS: Prior research has shown that preinjury employment status (employed vs unemployed) greatly influences the odds of successful RTW after TBI. A related hypothesis, that occupational classification also influences RTW outcome, has been understudied and has yielded conflicting results. The current study shows convincingly that the type of occupation influences RTW outcome, with the best prospect for RTW among people with professional/managerial jobs. Occupational category should be examined in the future development of predictive models for RTW after TBI.     

Functional limitations and depression after traumatic brain injury: examination of the temporal relationship

Pagulayan KF, Hoffman JM, Temkin NR, Machamer JE, Dikmen SS. Functional limitations and depression after traumatic brain injury: examination of the temporal relationship.

Objective

To examine the temporal relationship between self-reported injury-related functional limitations and depressive symptomatology after traumatic brain injury (TBI).

Design

A longitudinal cohort study with 3 evaluation points.

Setting

A level I trauma center.

Participants

Adolescents and adults (N=135) with complicated mild to severe TBI (72% had complicated mild injuries) who were recruited within 24 hours of injury and then completed the measure at all 3 time points.

Interventions

Not applicable.

Main Outcome Measures

Sickness Impact Profile and Center for Epidemiological Studies−Depression Scale.

Results

Individuals who reported more depressive symptomatology consistently endorsed more injury-related difficulties, showing the strong relationship between depression and perceived psychosocial functioning. Examination of these relationships over time revealed that increased depressive symptomatology follows higher levels of perceived injury-related changes but that reports of injury-related changes are not associated with earlier depression. These findings suggest a unidirectional temporal relationship between these variables.

Conclusions

Perceived changes in daily functioning appear to influence emotional well-being over time after TBI. However, depressive symptoms do not appear to negatively impact individuals' perception of later functioning. These results further our understanding of the complicated relationship between these variables and may have important implications for treatment of depression after TBI.     

Access to inpatient rehabilitation after violence-related traumatic brain injury

OBJECTIVES: To examine injury characteristics, demographics, and discharge disposition after traumatic brain injury of violent or nonviolent cause. DESIGN: Cohort study. SETTING: Level I trauma center. PARTICIPANTS: Patients (N=1807) admitted with a Head Abbreviated Injury Score (AIS) of 2 or more over a 2-year period. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Injury cause was classified as violent or nonviolent. Discharge disposition was classified as home, inpatient rehabilitation, skilled nursing facility (SNF), and other. RESULTS: The violence group was more likely to be male, to include individuals from diverse racial groups, to have an alcohol level above the legal limit, to have a more severe Head AIS, and to have Medicaid funding and equal access to inpatient rehabilitation compared with the nonviolence group. The violence group, though, was more likely to be discharged to home than to inpatient rehabilitation and more likely to be discharged to inpatient rehabilitation than to an SNF. The nonviolence group had a longer acute care length of stay and a higher rate of injuries to other body systems. CONCLUSIONS: People with violence-related injuries often present unique rehabilitation challenges. After accounting for injury severity and demographics, there was no evidence of bias against the violently injured in gaining access to inpatient rehabilitation services.     

Feasibility of a brief neuropsychologic test battery during acute inpatient rehabilitation after traumatic brain injury

Kalmar K, Novack TA, Nakase-Richardson R, Sherer M, Frol AB, Gordon WA, Hanks RA, Giacino JT, Ricker JH. Feasibility of a brief neuropsychologic test battery during acute inpatient rehabilitation after traumatic brain injury.

Objectives

To determine (1) if more than 50% of patients with moderate to severe traumatic brain injury (TBI) who met study criteria can complete a battery of neuropsychologic tests in less than 75 minutes 2 to 6 weeks after injury regardless of posttraumatic amnesia (PTA) status; (2) which tests are most likely to be completed; and (3) range of scores obtained.

Design

Prospective multicenter observational study.

Setting

Acute inpatient neurorehabilitation hospitals.

Participants

Screened 543 Traumatic Brain Injury Model System patients with moderate to severe TBI; 354 were tested at 2 to 6 weeks postinjury.

Interventions

Not applicable.

Main Outcome Measure

Percentage of patients able to complete the neuropsychologic tests in less than 75 minutes.

Results

Two hundred eighteen (62%) patients completed the battery in 66 minutes on average. Mean interval from injury to testing was 28.3±7.1 days. Tests completed with the highest frequency were California Verbal Learning Test−II, FAS, and animal naming. Performance was less impaired (P<.001) on all measures for patients who had emerged from PTA.

Conclusions

Approximately two thirds of screened patients were able to complete a brief neuropsychologic test battery at 2 to 6 weeks postinjury, regardless of PTA status. Although patients out of PTA were less impaired on all test measures, confusion did not preclude participation in the test battery or prohibit assignment of test scores. Early neuropsychologic assessment after TBI is feasible even for many patients who are still in PTA.     

Employment after traumatic brain injury: differences between men and women

Corrigan JD, Lineberry LA, Komaroff E, Langlois JA, Selassie AW, Wood KD. Employment after traumatic brain injury: differences between men and women.

Objective

To determine whether there are sex differences in employment 1 year after traumatic brain injury.

Design

Prospective cohort.

Setting

Acute care hospitals in South Carolina and Traumatic Brain Injury Model Systems (TBIMS) rehabilitation centers.

Participants

Subjects in the TBIMS national dataset and the South Carolina Traumatic Brain Injury Follow-up Registry who were expected to be working before injury and followed at 1 year postinjury.

Interventions

Not applicable.

Main Outcome Measure

Change in employment from preinjury to 1 year postinjury.

Results

When other measured influences on change in hours worked were held constant, there were significant interactions for sex by age and sex by marital status. Compared with men, women were more likely to decrease hours or stop working, except in the oldest age group (55−64y) in which men were more likely to stop working. For women, there was a pattern showing better employment outcomes as age increased. Decreased employment for women was most evident for married women, who were much more likely to reduce hours or stop working. There was also a tendency for divorced women to be more likely to stop working when compared with divorced men.

Conclusions

These findings run counter to the current literature. Although definitive explanations must await future studies, causal factors arising from differential societal behavior toward women as well as discriminatory attitudes about women and employment deserve further study.     

Comparison between successful and failed sit-to-stand trials of a patient after traumatic brain injury

OBJECTIVE: To compare the peak whole-body center of mass (COM) velocities and joint angular contributions in successful and unsuccessful sit-to-stand (STS) trials in a subject with traumatic brain injury (TBI). DESIGN: Single-case study. SETTING: Motion research laboratory. PARTICIPANT: A 24-year-old man who was 3.5 years post-TBI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Peak horizontal and vertical velocities of the whole-body COM and peak angular velocities of the ankle, knee, hip, and shoulder joints. RESULTS: The peak whole-body COM vertical velocity was significantly lower in the unsuccessful STS trials. Angular velocities at the hip, knee, ankle, and shoulder joints in successful trials exceeded those in unsuccessful trials (P<.001). The subject's peak knee extension velocity was the single major predictor of the peak whole-body COM vertical velocity (r(2)=.90). Knee extension angular velocities greater than 3.25 radian/s were associated with successful STS trials. Knee extension angular velocities between 2.75 and 3.25 radian/s were associated with successful rising 50% of the time; the subject had no success in rising when velocities were less than 2.75 radian/s. CONCLUSIONS: For this subject, sit-back failures occurred in STS attempts characterized by peak whole-body COM vertical velocities that were lower than those generated in successful rising trials. These unsuccessful rising attempts were primarily the result of the subject's inability to generate sufficient knee extension angular velocity.     

Neuropsychologic and functional outcome after complicated mild traumatic brain injury

Kashluba S, Hanks RA, Casey JE, Millis SR. Neuropsychologic and functional outcome after complicated mild traumatic brain injury.

Objective

To investigate the extent to which neuropsychologic and functional outcome after complicated mild traumatic brain injury (TBI) parallels that of moderate TBI recovery.

Design

A longitudinal study comparing neuropsychologic and functional status of persons with complicated mild TBI and moderate TBI at discharge from inpatient rehabilitation and at 1 year postinjury.

Setting

Rehabilitation hospital with a Traumatic Brain Injury Model System.

Participants

Persons with complicated mild TBI (n=102), each with an intracranial brain lesion documented through neuroimaging and a highest Glasgow Coma Scale (GCS) score in the emergency department between 13 and 15, and 127 persons with moderate TBI.

Interventions

Not applicable.

Main Outcome Measures

FIM instrument, Disability Rating Scale, Community Integration Questionnaire, Wechsler Memory Scale logical memory I and II, Rey Auditory Verbal Learning Test, Trail-Making Test, Controlled Oral Word Association Test, Symbol Digit Modalities Test, Wisconsin Card Sorting Test, and block design.

Results

Few differences in neuropsychologic performance existed between the TBI groups. Less severely impaired information processing speed and verbal learning were seen in the complicated mild TBI group at rehabilitation discharge and 1 year postinjury. Despite overall improvement across cognitive domains within the complicated mild TBI group, some degree of impairment remained at 1 year postinjury on those measures that had identified participants as impaired soon after injury. No differences on functional ability measures were found between the TBI groups at either time period postinjury, with both groups exhibiting incomplete recovery of functional status at the 1-year follow-up.

Conclusions

When classifying severity of TBI based on GCS scores, consideration of a moderate injury designation should be given to persons with an intracranial bleed and a GCS score between 13 and 15.     

The minimally conscious state and recovery potential: a follow-up study 2 to 5 years after traumatic brain injury

OBJECTIVE: To document recovery in persons who were in the minimally conscious state (MCS) for at least 1 month after traumatic brain injury (TBI). DESIGN: Patient series. SETTING: Participants who had been discharged from an inpatient rehabilitation unit. PARTICIPANTS: Eighteen people with TBI and their relatives. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Western Neuro Sensory Stimulation Profile, Disability Rating Scale (DRS), FIM instrument, Dementia Rating Scale, and Sydney Psychosocial Reintegration Scale (SPRS). RESULTS: Level of functioning at follow-up varied from extremely severe disability or greater on the DRS (n=4) to mild disability (n=1). These outcomes were corroborated by results of the FIM and the Dementia Rating Scale. All participants experienced some (44%) or major (56%) change in their level of psychosocial functioning on the SPRS compared with their preinjury level. There were no significant correlations between duration of time in the MCS and outcome on FIM, DRS, or SPRS. CONCLUSIONS: These results highlight the heterogeneity of outcome even after a prolonged duration of MCS after TBI. A large proportion of the patients was functionally independent in basic daily activities, although all experienced residual impairments and disabilities. The low correlation coefficients between duration of MCS and the outcome measures suggest that prognostic statements based on length of time a person is in the MCS cannot be made with confidence.