Race/ethnicity differences in satisfaction with life among persons with traumatic brain injury.

OBJECTIVE: To determine differences in life satisfaction at 1-year post-TBI among Caucasian, African American, Hispanic, and Asian individuals with TBI, after adjusting for covariates that significantly differ between ethnic groups and/or affect the Satisfaction with Life Scale (SWLS) at one year post-injury. DESIGN: Retrospective study. SETTING: Longitudinal dataset of the TBI Model Systems National Database. PARTICIPANTS: 3,368 individuals with moderate to severe TBI (2478 Caucasian, 629 African American, 180 Hispanic, and 81 Asian/Pacific Islander) hospitalized between 1989 and 2005. MAIN OUTCOME MEASURES: Satisfaction with Life Total score at 1 year post injury. RESULTS: African Americans had 3.21 units lower SWLS scores one year post-injury than Asian/Pacific Islanders (95% CI = 0.61-5.81) and 1.99 units lower SWLS scores than Caucasians (95% CI = 0.97-3.00) after controlling for marital status, employment at admission, cause of injury, FIM at discharge, and LOS in acute care. CONCLUSIONS: African Americans have poorer self-reported life satisfaction than Caucasians and Asians one year after TBI. This effect is not due to pre-injury marital or employment status, cause of injury, nor injury severity or functional status. Further research on the factors which might explain these differences is warranted, so that targeted rehabilitation programs can be designed and implemented that enhance quality of life for all individuals who have suffered a TBI.

Ethnicity/racial differences in employment outcomes following spinal cord injury.

OBJECTIVE: To examine differences in employment outcomes among Hispanics and Caucasians with Spinal Cord Injuries at one year post-injury. DESIGN: Retrospective study. SETTING: Longitudinal dataset of the SCI Model Systems. PARTICIPANTS: 11,424 Individuals diagnosed with spinal cord injury (1369 Hispanics and 10055 Caucasians) that were enrolled in the National Spinal Cord Injury Statistical Center (NSCISC) database and interviewed during their scheduled one-year post-injury follow-up evaluation between 1975 and 2006. MAIN OUTCOME MEASURES: Employment status (competitively employed, unemployed and other). RESULTS: After adjusting for age, gender, marital status, education level, employment status at admissions, cause of injury, category of neuro-impairment, and ASIA impairment scale, race/ethnicity has a significant effect on employment status at 1 year post-injury. Specifically, the odds of unemployment versus employment were 1.864 times greater for Hispanics than for Caucasians (95% CI = 1.478, 2.349) and the odds of unemployment versus other were 1.980 times greater for Hispanics than for Caucasians (95% CI = 1.625, 2.413). CONCLUSIONS: Racial disparities do exist in successful employment after 1 year post SCI, particularly between Caucasians and Hispanics. Future research should focus on what factors contribute to this disparity, along with forming new education and rehabilitation strategies to improve return-to-work outcomes for Hispanics after SCI.

Motor threshold in transcranial magnetic stimulation: the impact of white matter fiber orientation and skull-to-cortex distance.

The electrophysiology of transcranial magnetic stimulation (TMS) of motor cortex is not well understood. In this study, we investigate several structural parameters of the corticospinal tract and their relation to the TMS motor threshold (MT) in 17 subjects, with and without schizophrenia. We obtained structural and diffusion tensor MRI scans and measured the fractional anisotropy and principal diffusion direction for regions of interest in the corticospinal tract. We also measured the skull-to-cortex distance over the left motor region. The anterior-posterior trajectory of principle diffusion direction of the corticospinal tract and skull-to-cortex distance were both found to be highly correlated with MT, while fractional anisotropy, age and schizophrenia status were not. Two parameters-skull-to-cortex distance and the anterior component of the principle diffusion direction of the corticospinal tract as it passes the internal capsule-are highly predictive of MT in a linear regression model, and account for 82% of the variance observed (R2 = 0.82, F = 20.27, P < 0.0001) in measurements of MT. The corticospinal tract's anterior-posterior direction alone contributes 13% of the variance explained.

Neurocognitive deficits and prefrontal cortical atrophy in patients with schizophrenia.

RATIONALE: Cognitive deficits are of particular importance in schizophrenia since they are strongly associated with poor prognosis. We investigated the relationship between prefrontal cortical atrophy as measured by MRI and the neuropsychological performance of participants diagnosed with DSM-IV-TR schizophrenia. METHODS: Fourteen unmedicated adult patients and thirteen matched controls were studied. Subjects underwent MRI yielding 1 mm isotropic T1-weighted images. Voxel based morphometry was applied to all images using SPM5. The mean gray level of Brodmann area (BA) 9 was also extracted and evaluated using simple regression along with relative score differences on patients neuropsychological tests compared to controls. RESULTS: Patients exhibited a poorer performance on the Controlled Word Association Task (COWAT), Wisconsin Card Sorting Test (WCST) and Trail Making Test (TMT). Patients also presented a greater level of apathy as indexed by the Apathy Evaluation Scale (AES). There was a significant decrease in gray matter volume in patients with schizophrenia in left supplementary motor area, bilateral superior frontal gyrus, left middle frontal gyrus, right opercular area, left angular gyrus, left superior temporal gyrus and left cerebellar hemisphere. Within the schizophrenia group, decreased BA9 gray matter volume was correlated with poorer performance on the WCST and TMT-B. CONCLUSION: Prefrontal gray matter abnormalities in schizophrenia patients may be associated with some symptoms including difficulties with set-shifting and decreased mental flexibility. Further studies evaluating prefrontal connectivity may clarify if such impairment results from abnormalities of the frontal area alone, or are a result of altered networks involving the frontal and extra-frontal areas.