Workers' risk of unemployment after traumatic brain injury: a normed comparison.

We examined, among those persons working preinjury, the risk of unemployment 1 year after traumatic brain injury (TBI) relative to expected risk of unemployment for the sample under a validated risk-adjusted econometric model of employment in the U.S. population. Results indicate that 42% of TBI cases were unemployed versus 9% expected, relative risk (RR) = 4.5, 95% confidence interval (CI) (4.12, 4.95). The relative risk for unemployment was higher among males, those with higher education, persons with more severe injuries, and more impaired early neuropsychological or functional status. Difference in unemployment rates gave similar results for gender, severity of injury, and early neuropsychological and functional status. However, for education, the excess was smaller among those more highly educated, but the unemployment rate in the more highly educated in the general population was sufficiently small to yield a larger relative risk. In conclusion, after accounting for underlying risk of unemployment in the general population, unemployment is substantially higher after TBI for people who were employed when they were injured. The differential employment status varies depending on demographics, severity of brain injury, early functional outcome, and neurobehavioral indicators. For characteristics such as education, associated with rates of unemployment in the general population, different methods used to compare the rates may yield different results.

Self-report of extent of recovery and barriers to recovery after traumatic brain injury: a longitudinal study.

OBJECTIVE: To examine the perspective of survivors of traumatic brain injury (TBI) regarding the extent and nature of their recovery over time. DESIGN: Inception cohort, longitudinal study. SETTING: Level I trauma center. PARTICIPANTS: One hundred fifty-seven consecutively hospitalized individuals with TBI (mean age, 36.1 yr; 80% men) with a broad range of injury severity. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants reported the extent of their recovery and barriers to full recovery at 1, 6, and 12 months. RESULTS: Participants reported a median return to normal at the 3 follow-up times of 65%, 80%, and 85%. After 1 month, self-reported extent of recovery correlated well with performance on the Glasgow Outcome Scale (p <.001 at 6 and 12 mo) and Wechsler Adult Intelligence Scale Performance IQ (p =.001 at 12 mo). The major reported barrier to recovery was physical difficulties, which constituted over half of the concerns at all time periods. Report of physical-related concerns decreased significantly (p =.002) over time whereas cognition-related concerns increased significantly (p =.02). CONCLUSION: Brain injury survivors consider themselves to have greater recovery than previously reported by clinicians or family members, consider physical problems a significant factor in their recovery, and appear to become more aware of cognitive impairments over time.

Utility of a composite measure to detect problematic alcohol use in persons with traumatic brain injury.

OBJECTIVES: To examine factors complicating the study of alcohol-related effects in traumatic brain injury (TBI) patients and to evaluate a composite measure to categorize such patients according to degree of alcohol-related problems. DESIGN: Inception cohort. SETTING: Level I trauma center. PATIENTS: Consecutively hospitalized adult TBI patients (n = 156; 73% men; 87% Caucasian; mean age, 30yr; mean education, 12yr). Selection criteria required objective evidence of brain trauma; minimum survival of 1 month postinjury; age 15 years or older; and English speaking. MAIN OUTCOME MEASURES: An index of problematic drinking based on a measure created by combining blood-alcohol level, quantity-frequency of consumption, and the Short Michigan Alcoholism Screening Test. Preinjury characteristics were obtained through structured interview. RESULTS: Participants with highly problematic drinking showed poorer premorbid psychosocial functioning, including lower educational attainment, greater likelihood of problems with the law, lower perceived social support, and greater prevalence of other substance abuse. CONCLUSION: The composite index is useful in identifying problematic drinkers among TBI patients. Results have implications for interpreting and planning research on the role of alcohol in TBI outcomes.

Neuropsychological effects of valproate in traumatic brain injury: a randomized trial.

OBJECTIVES: To examine the neuropsychological side effects of valproate (VPA) given to prevent posttraumatic seizures. METHODS: In a randomized, double-masked, parallel group clinical trial, we compared the seizure prevention and neuropsychological effects of 1 or 6 months of VPA to 1 week of phenytoin. We studied 279 adult subjects who were randomized within 24 hours of injury and examined with a battery of neuropsychological measures at 1, 6, and 12 months after injury. We examined drug effects cross-sectionally at 1, 6, and 12 months and longitudinally by examining differential change from 1 to 6 months and from 6 to 12 months as a function of protocol-dictated changes in treatment. RESULTS: No significant adverse or beneficial neuropsychological effects of VPA were detected. CONCLUSIONS: Valproate (VPA) appears to have a benign neuropsychological side effects profile, making it a cognitively safe antiepileptic drug to use for controlling established seizures or stabilizing mood. However, based on this study, VPA should not be used for prophylaxis of posttraumatic seizures because it does not prevent posttraumatic seizures, there was a trend toward more deaths in the VPA groups, and it did not have positive effects on cognition.

Side effects and mortality associated with use of phenytoin for early posttraumatic seizure prophylaxis.

OBJECT: The goals of this study were to determine if the use of phenytoin to prevent early posttraumatic seizures following head injury was associated with significant adverse side effects and also to determine if the reduction in early posttraumatic seizures after phenytoin administration was associated with a change in mortality rates in head-injured patients. METHODS: The authors performed a secondary analysis of the data obtained in a prospective double-blind placebo-controlled study of 404 patients who were randomly assigned to receive phenytoin or placebo for the prevention of early and late posttraumatic seizures. The incidence of adverse drug effects during the first 2 weeks of treatment, however, was low and not significantly different between the treated and placebo groups. Hypersensitivity reactions occurred in 0.6% of the patients in the phenytoin-treated group compared with 0% in the placebo group (p = 1.0) during week 1, and in 2.5% of phenytoin-treated compared with 0% of placebo-treated patients (p = 0.12) for the first 2 weeks of treatment. Mortality rates were also similar in both groups. Although the mortality rate was higher in patients who developed seizures, this increase was related to the greater severity of the injuries sustained by these patients at the time of the original trauma. CONCLUSIONS: The results of this study indicate that the incidence of early posttraumatic seizure can be effectively reduced by prophylactic administration of phenytoin for 1 or 2 weeks without a significant increase in drug-related side effects. Reduction in posttraumatic seizure during the 1st week, however, was not associated with a reduction in the mortality rate.

Valproate therapy for prevention of posttraumatic seizures: a randomized trial.

OBJECT: Seizures frequently accompany moderate to severe traumatic brain injury. Phenytoin and carbamazepine are effective in preventing early, but not late, posttraumatic seizures. In this study the authors compare the safety and effectiveness of valproate with those of short-term phenytoin for prevention of seizures following traumatic brain injury. METHODS: The study was a randomized, double-blind, single-center, parallel-group clinical trial. Treatment began within 24 hours of injury. One hundred thirty-two patients at high risk for seizures were assigned to receive a 1-week course of phenytoin, 120 were assigned to receive a 1-month course of valproate, and 127 were assigned to receive a 6-month course of valproate. The cases were followed for up to 2 years. The rates of early seizures were low and similar when using either valproate or phenytoin (1.5% in the phenytoin treatment group and 4.5% in the valproate arms of the study; p = 0.14, relative risk [RR] = 2.9, 95% confidence interval [CI] 0.7-13.3). The rates of late seizures did not differ among treatment groups (15% in patients receiving the 1-week course of phenytoin, 16% in patients receiving the 1-month course of valproate, and 24% in those receiving the 6-month course of valproate; p = 0.19, RR = 1.4, 95% CI 0.8-2.4). The rates of mortality were not significantly different between treatment groups, but there was a trend toward a higher mortality rate in patients treated with valproate (7.2% in patients receiving phenytoin and 13.4% in those receiving valproate; p = 0.07, RR = 2.0, 95% CI 0.9-4.1). The incidence of serious adverse events, including coagulation problems and liver abnormalities, was similar in phenytoin- and valproate-treated patients. CONCLUSIONS: Valproate therapy shows no benefit over short-term phenytoin therapy for prevention of early seizures and neither treatment prevents late seizures. There was a trend toward a higher mortality rate among valproate-treated patients. The lack of additional benefit and the potentially higher mortality rate suggest that valproate should not be routinely used for the prevention of posttraumatic seizures.

Emotional and behavioral adjustment after traumatic brain injury.

OBJECTIVES: To examine emotional and behavioral adjustment and recovery over 1 year after traumatic brain injury (TBI), and to determine whether the difficulties, if present, are due to neurologic insult. DESIGN: Longitudinal evaluation of adjustment from 1 month to 1 year after injury. SETTING: Level I trauma center at a university hospital. PATIENTS: One hundred fifty-seven consecutively hospitalized adults with TBI and 125 trauma controls with other system injuries evaluated at 1 and 12 months after injury. MAIN OUTCOME MEASURES: Katz Adjustment Scale (KAS). RESULTS: The TBI group at 1 year follow-up demonstrated significant emotional and behavioral maladjustment, but such difficulties did not appear to be mediated by the brain injury, since the KAS scores for the TBI and trauma control groups were not significantly different. Those with moderate TBI reported greater difficulties than those with mild or severe injuries. Changes in adjustment over 1 year were common for both groups. Within the TBI group there was differential recovery: improvement in cognitive clarity, dysphoric mood, and emotional stability, but increased difficulties with anger management, antisocial behaviors, and self-monitoring. CONCLUSIONS: These results raise questions about commonly held beliefs that those with mild TBI report greater distress, and clarify some misconceptions regarding change in emotional and behavioral functioning over time.

Test-retest reliability and practice effects of expanded Halstead-Reitan Neuropsychological Test Battery.

Test-retest reliabilities and practice effects of a broad range of neuropsychological measures were examined in 384 normal or neurologically stable adults. Median test-retest interval was 11 months (range 3-16 months). The reliability estimates for most of the measures are reasonably good, ranging from .70 to low .90s. An exception is the relatively poor reliabilities of most memory measures. For all test measures, the value on initial testing is a strong determinant of the value on the second examination. Practice effects are seen on most measures. The magnitude of the practice effects, however, varies as a function of type of measure, test-retest interval, age, and overall competency level of the participant. This study provides several types of retest information that may be useful for future research and clinical work: comparative reliabilities of the various measures, estimate of error variability associated with each administration, standard deviation of the change, and comparative magnitude of practice effects on various tests.

Detecting significant change in neuropsychological test performance: a comparison of four models.

A major use of neuropsychological assessment is to measure changes in functioning over time; that is, to determine whether a difference in test performance indicates a real change in the individual or just chance variation. Using 7 illustrative test measures and retest data from 384 neurologically stable adults, this paper compares different methods of predicting retest scores, and of determining whether observed changes in performance are unusual. The methods include the Reliable Change Index, with and without correction for practice effect, and models based upon simple and multiple regression. For all test variables, the most powerful predictor of follow-up performance was initial performance. Adding demographic variables and overall neuropsychological competence at baseline significantly but slightly improved prediction of all follow-up scores. The simple Reliable Change Index without correction for practice performed least well, with high error rates and large prediction intervals (confidence intervals). Overall prediction accuracy was similar for the other three methods; however, different models produce large differences in predicted scores for some individuals, especially those with extremes of initial test performance, overall competency, or demographics. All 5 measures from the Halstead-Reitan Battery had residual (observed--predicted score) variability that increased with poorer initial performance. Two variables showed significant nonnormality in the distribution of residuals. For accurate prediction with smallest prediction--confidence intervals, we recommend multiple regression models with attention to differential variability and nonnormality of residuals.

Aging effect on psychosocial outcome in traumatic brain injury.

OBJECTIVE: To examine the effects of age on outcome in persons with traumatic brain injury. DESIGN: Longitudinal cohort design. SETTING: Level I trauma center. PATIENTS: A total of 411 hospitalized subjects with mild to severe traumatic brain injury prospectively studied to 1 year; their age range was 18 to 89 years. MAIN OUTCOME MEASURES: Glasgow Outcome Scale, living situation, and employment. RESULTS: Increasing age is associated with increasing levels of psychosocial limitations, especially in persons 60 years of age and older. Part of the reason is the greater severity of injury sustained by older persons as reflected in longer coma (despite equivalent initial coma depth) and greater numbers of complications and surgeries for subdural hematomas. However, the consequences of traumatic brain injuries appear to worsen with increasing age at each level of brain injury severity examined, including the milder injuries. CONCLUSIONS: Older adults clearly show less complete recovery 1 year after brain injury than younger adults, either because they have reduced reserves with which to tolerate brain injury or because their physiologic status creates a more destructive injury. Glasgow Coma Scale alone may underestimate the severity of brain injury in the aged as well as its associated consequences. Caution is advised in generalizing findings based principally on younger individuals to older adults with traumatic brain injuries.

Risk of seizure recurrence after the first late posttraumatic seizure.

OBJECTIVE: To determine the incidence and risk factors for seizure recurrence after the onset of late posttraumatic seizures (ie, seizures occurring more than 7 days after injury). DESIGN: Longitudinal cohort design. SETTING: Level 1 trauma center. PATIENTS: Sixty-three moderately to severely head-injured adults who developed late posttraumatic seizures during the course of their participation in a randomized, placebo-controlled study of the effectiveness of prophylactic phenytoin (Dilantin) for prevention of posttraumatic seizures. MAIN OUTCOME MEASURES: Time from the first unprovoked late seizure to time of seizure recurrence. RESULTS: The cumulative incidence of recurrent late seizures was 86% by approximately 2 years. However, the frequency of recurrent seizures varied considerably across subjects: 52% experienced at least five late seizures, and 37% had 10 or more late seizures within 2 years of the first late seizure. The relative risk of recurrence was highest in patients with a history of acute subdural hematoma and prolonged coma (ie, longer than 7 days). CONCLUSIONS: When late seizures develop after severe head injury, the probability of recurrence is high, which suggests that patients be treated aggressively with anticonvulsant medication after a first unprovoked late seizure.

The impact of posttraumatic seizures on 1-year neuropsychological and psychosocial outcome of head injury.

This study examined the relationship of posttraumatic seizures and head injury severity to neuropsychological performance and psychosocial functioning in 210 adults who were prospectively followed and assessed 1 year after moderate to severe traumatic head injury. Eighteen percent (n = 38) of the patients experienced 1 or more late seizures (i.e., seizures occurring 8 or more days posttrauma) by the time of the 1-year followup. As expected, the head injured patients who experienced late posttraumatic seizures were those with the most severe head injuries, and they were significantly more impaired on the neuropsychological and psychosocial measures compared to those who remained seizure free. However, after the effects of head injury severity were controlled, there were no significant differences in neuropsychological and psychosocial outcome at 1 year as a function of having seizures. These findings suggest that worse outcomes in patients who develop posttraumatic seizures up to 1 year posttrauma largely reflect the effects of the brain injuries that cause seizures, rather than the effect of seizures.

Alcohol use before and after traumatic head injury.

STUDY OBJECTIVE: To determine (1) the significance of blood alcohol level in the emergency department in history of alcohol abuse and (2) the significance of habitual alcohol use in head-injured patients before and after injury. DESIGN: Inception cohort study with 1-year follow-up. SETTING: Level I trauma center. PARTICIPANTS: One hundred ninety-seven hospitalized adult head-injury survivors with a broad spectrum of head-injury severity. RESULTS: Alcohol use and behavioral problems associated with alcohol use were assayed before injury and in the month and year after injury. The patients' blood alcohol levels in the ED were also examined. Preinjury alcohol abuse was frequent; 42% of the subjects were legally intoxicated while in the ED. The amount of drinking and magnitude of reported preinjury alcohol problems decreased soon after the injury but was followed by an increase by 1 year, although the amount of drinking did not return to the preinjury level (P < .0001). Patients with more severe head injuries decreased their drinking more than did those with less severe head injuries. The patients' blood alcohol levels in the ED were a good indicator of the magnitude of their preinjury alcohol problems (r = .51 to .59; each, P < .001). CONCLUSION: Preinjury habitual alcohol abuse is frequent in head-injured patients. Blood alcohol levels in the ED are indicative of history of problem drinking and might serve as a basis for treatment referral. The first weeks after injury in hospitalized patients may provide an opportunity to begin interventions because head-injured patients drink less at that time.

Classification and regression trees (CART) for prediction of function at 1 year following head trauma.

A cohort of 514 hospitalized head-injury survivors was identified based on their injury and 448 (87%) of them were followed for 1 year. Comprehensive neurobehavioral testing was performed 1 month and 1 year after injury. The authors developed predictions of six neuropsychological and two psychosocial outcomes 1 year after head injury. Prediction trees are presented for verbal IQ, Halstead's Impairment Index, and work status at 1 year. Early predictors of neurobehavioral outcome in survivors are similar to previously reported predictors of mortality. Extent (both depth and length) of coma and age are the medical and demographic variables most predictive of late outcome. Adding 1-month scores substantially improves prediction of neuropsychological variables. The classification and regression tree is a useful technique for predicting long-term outcome in patients with head injury. The trees are simple enough to be used in a clinical setting and, especially with 1-month scores, predictions are accurate enough for clinical utility.

One year psychosocial outcome in head injury.

Psychosocial outcome at one year post-injury was examined prospectively in 466 hospitalized head-injured subjects, 124 trauma controls, and 88 friend controls. The results indicate that head injury is associated with persistent psychosocial limitations. However, the presence and extent of limitations are related to the demographics of the population injured, to other system injuries sustained in the same accident, and particularly to the severity of the head injury. More severe head injuries are associated with limitations implying greater dependence on others including poorer Glasgow Outcome Scale (GOS) ratings, dependent living, unemployment, low income, and reliance on family and social subsidy systems. Head injury severity is more closely related to more objective indices of psychosocial outcome (e.g., employment) than to self-perceived psychosocial limitations, such as measured by the Sickness Impact Profile (SIP).

Neuropsychological outcome in relation to head injury severity. Contributions of coma length and focal abnormalities.

Neuropsychological test performances of 102 consecutive head-injured patients were evaluated at 1 mo and 1 yr after injury. The results of the study indicated that both coma length and the presence of focal abnormalities on computed tomography (CT) scans contribute independently to neuropsychological outcome. The effects of coma length are stronger than the effects of focal abnormalities evident on CT scans and continue to exert a stronger influence on neuropsychological outcome over the year postinjury. These results suggest that the extent of diffuse pathology may be a more important determinant of long-term behavioral outcome than the presence of focal lesions.

Employment following traumatic head injuries.

OBJECTIVE: Determine rates of, and factors predictive of, return to work in patients with civilian traumatic head injuries. DESIGN: Inception cohort study with 1- to 2-year follow-up. SETTING: Hospitalized patients in a level I trauma center. PATIENTS: Three hundred sixty-six hospitalized head-injured subjects who were workers before injury and 95 comparison subjects participated in prospective, longitudinal investigations of employment following head injury. Head-injured and comparison subjects were similar on basic demographics and preinjury employment status. The comparison subjects consisted of patients who sustained traumatic injury to the body but not to the head. MAIN OUTCOME MEASURE: Time taken to return to work following head injury. RESULTS: Survival methodology was used for analysis. Whether patients returned to work and when related to both the characteristics of the injured patients (eg, education, preinjury work history), the severity of head injury and associated neuropsychologic problems, and severity of other system injuries. More precise predictions were possible using the multivariate model. CONCLUSIONS: The present study provides a means of assessing employment potential predictively. This can be useful for clinical and research purposes. The results should be used cautiously and should stimulate discussions of appropriate use of services and resources to meet individual patients' needs.

Psychosocial recovery after head injury.

Psychosocial recovery after head injury was prospectively examined at 1 and 12 months postinjury in a group of 102 hospitalized adult head-injured patients representing a broad range of head injury severity. For comparison purposes, 102 friend controls were used. Outcome was assessed with a battery of psychosocial measures including the Sickness Impact Profile, the Head Injury Symptom Checklist, and the Modified Function Status Index. The results indicate that head-injury patients experience significant psychosocial problems (eg, ability to return to work, resume leisure activity, concentrate and remember information, feelings of irritability) at both 1 and 12 months postinjury but these difficulties improve over time. Whereas improvements occur in both psychosocial and physical areas of functioning, improvements are greater in the physical area. The nature and extent of difficulties seen vary as a function of head injury severity, and time from injury to observation. Finally, the results suggest that not all problems reported by head-injured patients are solely related to the injury (eg, irritability, anxiety, fatigue, or headaches).

Outcomes after cardiac arrest.

The simplest, most easily determined, and most easily understood outcomes after cardiac arrest are survival and awakening. Awakening is defined by the patient's being able to follow commands or produce comprehensible speech. Both occur at specific times, thus lending themselves to life-table analyses. Unfortunately, these simple measures are not adequate to characterize the disability that may be present in those who survive and awaken after cardiac arrest. For such patients, measures of independence are needed. These measures often require longer follow-up, direct contact with patients, and a greater understanding of the instrument to be used than for the simple measures. Investigators must decide based on the goals of a particular study what outcomes are most appropriate and the amount of resources that they are willing to devote to outcome assessment. As initial steps in resuscitation research, there may be more to gain from studies of large numbers of patients evaluated with simple measures than small numbers of patients evaluated intensively with more detailed measures.