Utility of post-traumatic amnesia in predicting 1-year productivity following traumatic brain injury: comparison of the Russell and Mississippi PTA classification intervals

BACKGROUND

Duration of post-traumatic amnesia (PTA) correlates with global outcomes and functional disability. Russell proposed the use of PTA duration intervals as an index for classification of traumatic brain injury (TBI) severity. Alternative duration-based schemata have been recently proposed as better predictors of outcome to the commonly cited Russell intervals.

OBJECTIVE

Validate a TBI severity classification model (Mississippi intervals) of PTA duration anchored to late productivity outcome, and compare sensitivity against the Russell intervals.

METHODS

Prospective observational data on TBI Model System participants (n=3846) with known or imputed PTA duration during acute hospitalisation. Productivity status at 1-year postinjury was used to compare predicted outcomes using the Mississippi and Russell classification intervals. Logistic regression model-generated curves were used to compare the performance of the classification intervals by assessing the area under the curve (AUC); the highest AUC represented the best-performing model.

RESULTS

All severity variables evaluated were individually associated with return to productivity at 1&emsp14;year (RTP1). Age was significantly associated with RTP1; however, younger patients had a different association than older patients. After adjustment for individually significant variables, the odds of RTP1 decrease by 14% with every additional week of PTA duration (95% CI 12% to 17%; p<0.0001). The AUC for the Russell intervals was significantly smaller than the Mississippi intervals.

CONCLUSIONS

PTA duration is an important predictor of late productivity outcome after TBI. The Mississippi PTA interval classification model is a valid predictor of productivity at 1&emsp14;year postinjury and provides a more sensitive categorisation of PTA values than the Russell intervals.

Age-related differences in length of stays, hospitalization costs, and outcomes for an injury-matched sample of adults with paraplegia

OBJECTIVE

To investigate the effects of age at injury on neurological and functional outcomes and hospitalization length of stays and charges following spinal cord injuries resulting in paraplegia.

METHODS

Subjects were 180 adults with paraplegia who were assessed in acute care and inpatient rehabilitation as part of the National Institute on Disability and Rehabilitation Research Model Spinal Cord Injury Systems. Age differences were examined by separating the sample into 3 age groups (18-39, 40-59, and 60+ years). A matched block design was used to control for injury characteristics. Cramer's statistic was used to identify age-related differences in qualitative variables; 3 x 5 one-way analysis of variance identified the main effects of age on quantitative variables. Tukey post hoc tests were performed to identify differences between age and age x injury characteristic variable levels. OUTCOME AND TREATMENT MEASURES: American Spinal Injury Association motor index scores, Functional Independence Measure (FIM) motor scores, discharge to private residence ratios, and hospitalization length of stays and charges were outcome and treatment measures.

RESULTS

Age-related differences were found for etiology and health care plan, as well as for preinjury marital status, education level, and employment status. The main effects of age at injury were found for the following treatment and outcome measures: rehabilitation length of stays, FIM motor scores at rehabilitation discharge, FIM motor improvement (change), and FIM motor daily improvement (efficiency). Tukey post hoc tests revealed that older patients had longer rehabilitation stays, lower rehabilitation discharge FIM motor scores, and showed less improvement compared with younger and middle-aged injury-matched patients. No age-related differences were found in rates of discharge disposition.

CONCLUSIONS

Using a matched block design procedure, older patients are discharged with lower levels of functional independence and show lower levels of improvement despite longer rehabilitation stays when compared with younger patients. Older patients' neurological recovery appears equivocal to younger patients' recovery. In contrast to findings with a matched tetraplegia sample, older and younger patients with paraplegia are discharged to private residences at similar rates.

Nontraumatic vs. traumatic spinal cord injury: a rehabilitation outcome comparison

OBJECTIVE

Nontraumatic spinal cord injury (SCI) represents a significant proportion of individuals admitted for SCI rehabilitation; however, there is limited literature regarding their outcomes. As our society continues to age and nontraumatic injuries present with greater frequency, further studies in this area will become increasingly relevant. The objective of this study was to compare outcomes of patients with nontraumatic SCI with those with traumatic SCI after inpatient rehabilitation.

DESIGN

A longitudinal study with matched block design was used comparing 86 patients with nontraumatic SCI admitted to a SCI rehabilitation unit and 86 patients with traumatic SCI admitted to regional model SCI centers, controlling for age, neurologic level of injury, and American Spinal Injury Association impairment classification. Main outcome measures included acute and rehabilitation hospital length of stay, FIM scores, FIM change, FIM efficiency, rehabilitation charges, and discharge-to-home rates.

RESULTS

Results indicate that when compared with traumatic SCI, patients with nontraumatic SCI had a significantly (P < 0.01) shorter rehabilitation length of stay (22.38 vs. 41.35 days) and lower discharge FIM scores (57.3 vs. 65.6), FIM change (18.6 vs. 31.0), and rehabilitation charges ($25,050 vs. $64,570). No statistical differences were found in acute care length of stay, admission FIM scores, FIM efficiency, and community discharge rates.

CONCLUSIONS

The findings indicate that patients with nontraumatic SCI can achieve rates of functional gains and community discharge comparable with traumatic SCI. Whereas patients with traumatic SCI achieved greater overall functional improvement, patients with nontraumatic SCI had shorter rehabilitation length of stay and lower rehabilitation charges. These findings have important implications for the interdisciplinary rehabilitation process in the overall management and outcome of individuals with nontraumatic SCI.

Gender-related differences in acute rehabilitation lengths of stay, charges, and functional outcomes for a matched sample with spinal cord injury: a multicenter investigation

OBJECTIVE

To examine the effects of gender on length of stay (LOS), treatment costs, and outcomes by using a matched sample of patients with spinal cord injury (SCI).

DESIGN

A 2 x (15 x 3) mixed, block design was used retrospectively to analyze the impact of gender on subjects matched for age, American Spinal Injury Association (ASIA) motor impairment classification, and level of neurologic injury.

SETTING

Twenty medical centers in the federally sponsored Spinal Cord Injury Model Systems project.

PARTICIPANTS

One thousand seventy-four adult patients with SCI admitted between 1988 and 1998 were assessed at acute-care admission, inpatient rehabilitation admission, and inpatient rehabilitation discharge.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

ASIA motor index and FIM instrument admission, discharge, and efficiency scores; rehabilitation LOS and medical care charges; and discharge disposition.

RESULTS

Analysis revealed no gender-related differences in FIM motor scores on admission and discharge. No differences in FIM motor efficiencies or daily change were observed. No significant differences were found for ASIA motor scores on acute-care admission and rehabilitation discharge. No differences in acute rehabilitation LOS and charges were observed. No gender-related differences were seen in the likelihood of discharge to an institutional setting.

CONCLUSION

Gender was not a significant factor in functional outcome of SCI patients after acute rehabilitation.

The prevalence and symptom rates of depression after traumatic brain injury: a comprehensive examination

PRIMARY OBJECTIVE

Differing definitions of depression, limited sample sizes, and variability in methodologies have contributed to equivocal findings about the prevalence of depression among persons with traumatic brain injury. The present investigation used standardized diagnostic criteria and a large sample to identify the manifestations of depression after TBI.

METHODS AND PROCEDURES

722 outpatients with brain injury, referred for comprehensive assessment at a regional Level I trauma centre, were studied. Depressive symptoms were characterized utilizing standard DSM-IV criteria and the Neurobehavioural Functioning Inventory.

RESULTS

Forty-two per cent of patients with brain injury met the prerequisite number of symptoms for a DSM-IV diagnosis of major depressive disorder. Fatigue (46%), frustration (41%), and poor concentration (38%) were the most commonly cited manifestations of depression.

CONCLUSIONS

Many patients with brain injury are at great risk for developing depressive disorders. Future research should focus on prognostic factors, developing protocols for identification of high risk patients, and examining the efficacy of treatment interventions.

Relation of electromyography-induced pain to type of recording electrodes

Pain is an important consideration in the performance of needle electromyography (EMG). Prior investigations have suggested that pain is greater with a concentric needle electrode (CNE) than monopolar needle electrode (MNE). This prospective randomized study tested this hypothesis using improved methodology and disposable rather than reusable needle electrodes. Ninety consecutive outpatients were enrolled and randomized to CNE (diameter = 0.46 mm) or MNE (diameter = 0.41 mm) arms. Subjects underwent a standardized 4 limb-muscle needle EMG protocol during which pretest and posttest verbal analog pain scale (0-10) measures were obtained. As anticipated, EMG-induced pain was significantly higher (P < 0.001) than pre-EMG baseline pain. However, analysis of variance (ANOVA) revealed no significant differences in pain ratings between the CNE and MNE arms. Among other factors analyzed, only gender significantly influenced EMG-induced pain, with females reporting higher levels than males. Thus, pain is not an important selection criterion for type of disposable needle electrode.

Age, outcome, and rehabilitation costs after paraplegia caused by traumatic injury of the thoracic spinal cord, conus medullaris, and cauda equina

The object of this study was to investigate the relationships of age on neurologic and functional outcome, hospitalization length of stay (LOS), and hospital charges after spinal cord injury (SCI). At 20 medical centers, 2,169 consecutive adult patients with paraplegia SCI were assessed in acute care and inpatient rehabilitation. Outcome and treatment measures included the ASIA motor index score, functional independence measure, discharge to community ratio, LOS, and hospital charges. Age differences were examined by separating the sample into 11 age categories and conducting one-way analyses of variance on treatment, medical expense, and outcome measures that included the Functional Independence Measure (FIM) and ASIA motor index scores. Cramer's statistic was used to derive a chi-square value that indicated whether variables differed significantly in terms of age. Post-hoc Tukey tests were also performed. Age-related differences were found with multiple demographic variables. Significant differences between age categories were found with regard to the following treatment measures: ASIA motor index scores at acute-care admission and at discharge, rehabilitation LOS, inpatient rehabilitation hospitalization charges, total LOS, total hospitalization charges, FIM scores at inpatient rehabilitation admission and discharge, FIM change, and FIM efficiency. In conclusion, in patients with paraplegia, age appears to adversely affect functional outcome, rehabilitation LOS, and hospital costs. However, neurologic recovery as defined by the ASIA motor scores does not appear to be related to age.

A multicenter investigation of age-related differences in lengths of stay, hospitalization charges, and outcomes for a matched tetraplegia sample

OBJECTIVE

To examine the effects of age at injury on lengths of stay, treatment costs, and outcomes using a matched sample of tetraplegic spinal cord injury (SCI) patients.

DESIGN

Differences were examined by separating the sample into three age categories (18 to 34, 35 to 64, and 65+ years old) matched for American Spinal Injury Association (ASIA) Motor Impairment Classification and level of neurologic preservation bilaterally. Analysis of variance was used to examine age group differences for lengths of stay, medical expenses, and functional outcome.

SETTING

Sixteen medical centers in the federally sponsored Spinal Cord Injury Model Systems Project.

PARTICIPANTS

Three hundred seventy-five adult patients with tetraplegic SCI admitted between 1988 and 1996 were assessed at acute care admission, inpatient rehabilitation admission, and inpatient rehabilitation discharge.

MAIN OUTCOME MEASURES

ASIA Motor Index and Functional Independence Measure (FIM) admission, discharge, and efficiency scores; acute care and rehabilitation lengths of stay and medical care charges; and discharge disposition.

RESULTS

Analyses revealed equivalent lengths of stay and charges for all age groups. There were no age-related differences in ASIA and FIM Motor scores at acute care and inpatient rehabilitation admission. Younger patients' scores on the FIM Motor subscale improved significantly more than did middle and older patients'. The two younger groups of patients had a more significant improvement than did older patients, as indicated by ASIA Motor Index scores. When taking lengths of stay into account, the FIM motor scores of the youngest group of patients improved more quickly than those of the two older groups. Furthermore, the younger and middle age groups demonstrated greater treatment efficiency than the older patient group based on ASIA Motor Index score ratios. Younger patients were least likely to be discharged to institutional settings.

CONCLUSIONS

Along with neurologic and functional status, age should be considered when formulating treatment plans and prognostic statements. For older patients, alternative rehabilitation settings with lower-intensity treatment and lower charges may prove to be a more efficacious use of resources.

Nontraumatic spinal cord injury: incidence, epidemiology, and functional outcome

OBJECTIVES

To identify and compare the incidence, demographics, neurologic presentation, and functional outcome of individuals with nontraumatic spinal cord injury (SCI) to individuals with traumatic SCI.

DESIGN

A 5-year prospective study.

SETTING

Level I trauma center of a Regional SCI Model System.

PATIENTS

Two hundred twenty adult SCI admissions.

MAIN OUTCOME MEASURES

Demographics, etiology, level and completeness of injury, Functional Independent Measure (FIM) scores.

RESULTS

Of SCI admissions, 39% were nontraumatic in etiology (spinal stenosis, 54%; tumor, 26%). Compared to subjects with traumatic SCI, those individuals with nontraumatic SCI were significantly (p < .01) older and were more likely married, female, and retired. Injury characteristics revealed significantly more paraplegia and incomplete SCI within the nontraumatic SCI group (p < .01). Both nontraumatic and traumatic SCI individuals had significant FIM changes from rehabilitation admission to discharge (p < .01). Those with tetraplegia-incomplete nontraumatic SCI had significantly higher admission motor FIM scores and shorter rehabilitation length of stay than in the traumatic group (p < .05). Paraplegic-complete and paraplegic-incomplete nontraumatic SCI subjects had lower discharge motor FIM scores, FIM change, and FIM efficiency than those with traumatic SCI. Similar discharge-to-home rates were noted in both nontraumatic and traumatic SCI groups.

CONCLUSIONS

These data suggest that individuals with nontraumatic SCI represent a significant proportion of SCI rehabilitation admissions and, although differing from those with traumatic SCI in demographic and injury patterns, can achieve similar functional outcomes.

Etiology and incidence of rehospitalization after traumatic brain injury: a multicenter analysis

OBJECTIVE

To investigate incidence and etiology of rehospitalizations at 1, 2, and 3 years after traumatic brain injury.

DESIGN

Descriptive statistics were computed in a prospective study of etiology and incidence of rehospitalization at years 1, 2, and 3 postinjury. Analysis of variance (ANOVA) and chi2 were used to identify factors relating to rehospitalization; factors included length of stay, admission and discharge functional status, payer source, medical complications, injury severity, and demographics.

SETTING

Four medical centers in the federally sponsored Traumatic Brain Injury Model Systems. In each setting, the continuum of care includes emergency medical services, intensive and acute medical care, inpatient rehabilitation, and a spectrum of community rehabilitation services.

PARTICIPANTS

Six hundred sixty-five rehabilitation patients admitted to acute care within 24 hours of traumatic brain injury between 1989 and 1996.

MAIN OUTCOME MEASURES

Annual incidence and etiology of rehospitalization.

RESULTS

The annual incidence of rehospitalization ranged from 20% to 22.5%. Approximately half the rehospitalizations were for elective reasons. The most common reason for rehospitalization was for orthopedic or reconstructive surgery, followed by infectious disorders and general health maintenance. After the first year, the incidence of readmissions for seizures and psychiatric difficulties increased substantially. ANOVA and chi2 analyses were performed on data from the first year postinjury. No statistically significant associations were noted between incidence and etiology of rehospitalization and: demographics; injury severity; payer source for rehabilitation; concurrent injuries; acute care and rehabilitation length of stays; discharge Functional Assessment Measure; and discharge residence (p > .05).

CONCLUSIONS

There is a relatively stable but high rate of rehospitalization for at least 3 years after injury. The costs of rehospitalization should be considered when evaluating the long-term consequences of injury.

Concordance of patients' and family members' ratings of neurobehavioral functioning after traumatic brain injury

OBJECTIVE

To examine differences in family and patient evaluation of neurobehavioral functioning in adults with traumatic brain injury (TBI).

DESIGN

Differences were examined by conducting 70 paired sample t tests on scale items and 6 paired sample t tests on scale scores from a neurobehavioral inventory.

SETTING

Medical center outpatient clinic.

PARTICIPANTS

Three hundred one consecutive adult patients with TBI and 301 informants, primarily family members, completed the neurobehavioral inventory.

MAIN OUTCOME MEASURE

Neurobehavioral Functioning Inventory (NFI) comprised of six scales with items describing symptoms and daily living problems.

RESULTS

Paired t test analyses of the six scales indicated that patients reported a significantly greater level of communication problems than did their matched family members. No differences were found for the other five scales. Paired t test analyses of the 70 scale items revealed significant differences in patient and family ratings for only 13 items. In all 13 instances, patients reported greater levels of dysfunction than were reported by their family members. Analysis of variance (ANOVA) indicated a main effect of injury severity for only the Communication and Memory/Attention scales.

CONCLUSIONS

Findings indicate general agreement between family members and patients regarding patients' everyday problems. Results do not support contentions that patients tend to underestimate difficulties. Agreement levels appear related to injury severity, item specificity, and item content. More research is needed to identify other variables relating to agreement levels, including age, injury severity, and amount of contact between patients and family members.

Agreement between persons with traumatic brain injury and their relatives regarding psychosocial outcome using the Community Integration Questionnaire

OBJECTIVE

To extend psychometric research on the Community Integration Questionnaire (CIQ) by comparing patients' reports with those of family members.

DESIGN

Reports on community integration were obtained from family members and patients 1 year after brain injury. Kappa reliability coefficients were used to examine agreement for individual items on the questionnaire. Total scores for the three CIQ scales were compared between groups using independent samples t tests.

SETTING

Outpatient clinics affiliated with the four NIDRR traumatic brain injury Model System rehabilitation centers.

PARTICIPANTS

CIQ data were obtained for 259 adult patients with traumatic brain injury. For 122 cases, patients and family members provided corresponding data. In 101 cases, only self-reported data were available. In 36 cases, information was provided solely by family members. All patients received inpatient rehabilitation and were at least 16 years of age. The full range of brain injury severity was represented.

MAIN OUTCOME MEASURE

The 15-item CIQ, comprised of three scales, Home Integration, Productive Activity, and Social Integration.

RESULTS

Analysis of kappa values found "moderate" to "almost perfect" agreement levels for all 15 items. Almost-perfect ratings were found for three of the four items on the Productive Activity Scale. Comparisons were made between scale scores derived from patients and families. The Home Integration scale showed differences, with patient scores higher than those reported by family members (t = 3.51, p < .01). However, the difference in scores was attributable to small discrepancies on two items and was not considered clinically meaningful. The Total CIQ score also showed a difference, with patients reporting significantly higher levels of integration relative to family members (t = 2.30, p < .05). This difference was also attributable to discrepancies on two items of the Home Integration Scale.

CONCLUSIONS

The results have important implications for researchers who may be limited to one source of data. The hypothesis that patients and family members have very different perspectives of patients' community activities was not supported. Rather, similar ratings of individual activities were given with two exceptions, meal preparation and housekeeping. More research is needed to delineate relationships between agreement ratings and outcome categories.

Neuromuscular and somatic problems of post-acute brain injury patients

Information regarding traumatic brain injury sequelae in a sample of 503 traumatic brain injury patients was obtained using the Neurobehavioral Functioning Inventory (NFI). Data revealed that motor dysfunction was more frequently reported than somatic difficulties. Analyses of variance indicated that unemployed patients experienced significantly more motor problems than patients working 40 or more hours per week. No differences in the incidence of somatic complaints, headaches, or muscular pain were found between employed and unemployed patients. Data suggests that long-term, interdisciplinary rehabilitation may be cost effective, especially when viewed in the context of successful employment.