RESUMO
We obtained brain MRIs, plasma homocysteine levels and apolipoprotein E genotyping for 11 American Indian Alzheimer disease (AD) subjects and 10 Indian controls. We calculated white matter hyperintensity volume (WMHV), whole brain volume (WBV), and ratio of white matter hyperintensity volume to whole brain volume (WMHV/WBV). There were no significant differences between AD subjects and controls in gender, history of hypertension, diabetes, or history of high cholesterol, but hypertension and diabetes were more common among AD subjects. There was no difference between AD and control groups in age (range for all subjects was 61-89 years), % Indian heritage, waist size or body mass index. Median Indian heritage was 50% or greater in both groups. Range of education was 5-13 years in the AD group and 12-16 years in controls. Median plasma homocysteine concentration was higher in AD subjects (11 micromol/L vs. 9.8 micromol/L), but did not achieve statistical significance. Significantly more AD subjects had apolipoprotein Eepsilon4 alleles than did controls (63% vs.10%). Neuroimaging findings were not significantly different between the 2 groups, but AD subjects had greater WMHV (median 15.64 vs. 5.52 cc) and greater WMHV/WBV ratio (median 1.63 vs. 0.65 %) and a far greater range of WMHV. In combined AD subjects and controls, WBV correlated with BMI and age. WMHV and WMHV/WBV correlated inversely with MMSE scores (p = 0.001, 0.002, respectively). In addition, WMHV correlated positively with % Indian heritage (p = 0.047).
Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Encéfalo/patologia , Predisposição Genética para Doença/genética , Homocisteína/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/etnologia , Apolipoproteína E4/genética , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Análise Mutacional de DNA , Feminino , Testes Genéticos , Genótipo , Humanos , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/etnologia , Indígenas Norte-Americanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas/patologia , Polimorfismo Genético/genéticaRESUMO
BACKGROUND: An estimated 5.3 million people in the United States live with permanent disability related to traumatic brain injury (TBI). Access to rehabilitation after TBI is important in minimizing these disabilities. Ethnic disparities in access to health care have been documented in other diseases, but have not been studied in trauma care. We hypothesized that access to rehabilitation after TBI is influenced by race or ethnicity. METHODS: Retrospective analysis of the National Trauma Data Bank patients with severe blunt TBI (head abbreviated injury score 3-5, n = 58,729) who survived the initial hospitalization was performed. Placement into rehabilitation after discharge was studied in three groups: non-Hispanic white (NHW 77%), African American (14%), and Hispanic (9%). The two minority groups were compared with NHW patients using logistic regression to control for differences in age, gender, overall injury severity (injury severity score), TBI severity (head abbreviated injury score and Glasgow Coma Scale score), associated injuries, and insurance status. RESULTS: The three groups were similar in injury severity score, TBI severity, and associated injuries. After accounting for differences in potential confounders, including injury severity and insurance status, minority patients were 15% less likely to be placed in rehabilitation (odds ratio 0.85, 95% confidence interval 0.8-0.9, p < 0.0001). CONCLUSIONS: Ethnic minority patients are less likely to be placed in rehabilitation than NHW patients are, even after accounting for insurance status, suggesting existence of systematic inequalities in access. Such inequalities may have a disproportionate impact on long-term functional outcomes of African American and Hispanic TBI patients, and suggest the need for an in-depth analysis of this disparity at a health policy level.