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1.
Dement Geriatr Cogn Disord ; 53(4): 180-189, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38663362

RESUMO

INTRODUCTION: Neighborhood socioeconomic status (NSES) has been linked with overall health, and this study will evaluate whether NSES is cross-sectionally associated with cognition in non-Hispanic whites (NHWs) and Mexican Americans (MAs) from the Health and Aging Brain: Health Disparities Study (HABS-HD). METHODS: The HABS-HD is a longitudinal study conducted at the University of North Texas Health Science Center. The final sample analyzed (n = 1,312) were 50 years or older, with unimpaired cognition, and underwent an interview, neuropsychological examination, imaging, and blood draw. NSES was measured using the national area deprivation index (ADI) percentile ranking, which considered socioeconomic variables. Executive function and processing speed were assessed by the trail making tests (A and B) and the digit-symbol substitution test, respectively. Linear regression was used to assess the association of ADI and cognitive measures. RESULTS: MAs were younger, more likely to be female, less educated, had higher ADI scores, performed worse on trails B (all p < 0.05), and had lower prevalence of APOE4 + when compared to NHWs (p < 0.0001). A higher percentage of MAs lived in the most deprived neighborhoods than NHWs. For NHWs, ADI did not predict trails B or DSS scores, after adjusting for demographic variables and APOE4. For MAs, ADI predicted trails A, trails B, and DSS after adjusting for demographic covariates and APOE4 status. CONCLUSION: Our study revealed that living in an area of higher deprivation was associated with lower cognitive function in MAs but not in NHWs, which is important to consider in future interventions to slow cognitive decline.


Assuntos
Envelhecimento , Função Executiva , Americanos Mexicanos , Testes Neuropsicológicos , Classe Social , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Envelhecimento/psicologia , Cognição/fisiologia , Estudos de Coortes , Estudos Transversais , Disparidades nos Níveis de Saúde , Estudos Longitudinais , Americanos Mexicanos/psicologia , Características da Vizinhança , Velocidade de Processamento , Características de Residência , Texas/epidemiologia , Brancos/psicologia
2.
Alzheimers Dement ; 19(1): 36-43, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35235702

RESUMO

INTRODUCTION: Despite the clinical implementation, there remain significant gaps in our knowledge regarding the impact of race/ethnicity or common medical comorbidity on plasma Alzheimer's disease (AD) biomarkers. METHODS: Plasma biomarkers of amyloid beta (Aß)40, Aß42 , total tau, and neurofilament light chain (NfL) were measured across cognitively normal Mexican Americans (n = 445) and non-Hispanic Whites (n = 520). RESULTS: Dyslipidemia was associated with elevated Aß40 (P = .01) and Aß42 (P = .001) while hypertension was associated with elevated Aß40 (P = .003), Aß42 (P < .001), and total tau (P = .002) levels. Diabetes was associated with higher Aß40 (P < .001), Aß42 (P < .001), total tau (P < .001), and NfL (P < .001) levels. Chronic kidney disease (CKD) was associated with elevations in Aß40 (P < .001), Aß42 (P < .001), total tau (P < .001), and NfL (P < .001) levels. Mexican Americans had significantly lower Aß40 (P < .001) and higher total tau (P = .005) levels. DISCUSSION: Plasma AD biomarkers vary significantly in association with common medical comorbidities as well as ethnicity. These findings are important for those using these biomarkers in clinical practice and clinical trials.


Assuntos
Doença de Alzheimer , Humanos , Peptídeos beta-Amiloides , Etnicidade , Proteínas tau , Biomarcadores , Comorbidade , Fragmentos de Peptídeos
3.
Alzheimers Dement ; 19(11): 5086-5094, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37104247

RESUMO

INTRODUCTION: The influence of apolipoprotein E (APOE) genotype on mild cognitive impairment (MCI) and Alzheimer's disease (AD) is well studied in the non-Hispanic white (NHW) population but not in the Hispanic population. Additionally, health risk factors such as hypertension, stroke, and depression may also differ between the two populations. METHODS: We combined three data sets (National Alzheimer's Coordinating Center [NACC], Alzheimer's Disease Neuroimaging Initiative [ADNI], Health and Aging Brain Study: Health Disparities [HABS-HD]) and compared risk factors for MCI and AD between Hispanic and NHW participants, with a total of 24,268 participants (11.1% Hispanic). RESULTS: APOEε4 was associated with fewer all-cause MCI cases in Hispanic participants (Hispanic odds ratio [OR]: 1.114; NHW OR: 1.453), and APOEε2 (Hispanic OR: 1.224; NHW OR: 0.592) and depression (Hispanic OR: 2.817; NHW OR: 1.847) were associated with more AD cases in Hispanic participants. DISCUSSION: APOEε2 may not be protective for AD in Hispanic participants and Hispanic participants with depression may face a higher risk for AD. HIGHLIGHTS: GAAIN allows for discovery of data sets to use in secondary analyses. APOEε2 was not protective for AD in Hispanic participants. APOEε4 was associated with fewer MCI cases in Hispanic participants. Depression was associated with more AD cases in Hispanic participants.


Assuntos
Doença de Alzheimer , Apolipoproteínas E , Disfunção Cognitiva , Hispânico ou Latino , População Branca , Humanos , Envelhecimento , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Apolipoproteína E2/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/genética , Hispânico ou Latino/genética , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , Fatores de Risco , População Branca/genética , População Branca/psicologia , População Branca/estatística & dados numéricos
4.
Dement Geriatr Cogn Disord ; 51(1): 26-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35226898

RESUMO

INTRODUCTION: The APOEε4 allele is the single strongest genetic risk for late-onset Alzheimer's disease (AD). Prior work demonstrates that not only the APOEε4 allele varies by race/ethnicity but also the risk for AD and cognitive impairment conveyed by the APOEε4 allele varies by the racial/ethnic group as well as genetic ancestry. Here, we sought to examine the link between the APOEε4 and neuropsychological functioning among Mexican Americans (MAs). METHODS: Data were examined from 1,633 (852 MAs and 781 non-Hispanic Whites [NHWs]) participants of the Health & Aging Brain Study - Health Disparities (HABS-HD) and were enrolled with all requisite data to be included into the current analyses. RESULTS: The frequency of both ε4 and ε2 alleles was significantly lower among MAs as compared to NHWs. Among MAs, APOEε4 allele presence was associated specifically with poorer immediate and delayed memory (Wechsler Memory Scale - Third Edition [WMS-III] Logical Memory and Spanish-English Verbal Learning Test [SEVLT]). Among NHWs, APOEε4 allele presence was associated with poorer immediate and delayed memory as well as worse executive functioning (Trials B) and verbal fluency (Animal naming). DISCUSSION/CONCLUSION: The APOEε4 allele was associated with poorer cognition across multiple domains among NHWs; however, allele presence was specifically associated with poorer memory performance among MAs. When combined with prior work, the current findings demonstrate that the risk factors associated with cognitive dysfunction differ among MAs as compared to NHWs and require additional investigation.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Envelhecimento/genética , Doença de Alzheimer/genética , Doença de Alzheimer/psicologia , Apolipoproteína E4/genética , Encéfalo , Etnicidade , Humanos , Americanos Mexicanos/genética , Testes Neuropsicológicos
5.
Alzheimers Dement ; 18(1): 77-87, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34057802

RESUMO

INTRODUCTION: Representation of Mexican Americans in Alzheimer's disease (AD) clinical research has been extremely poor. METHODS: Data were examined from the ongoing community-based, multi-ethnic Health & Aging Brain among Latino Elders (HABLE) study. Participants underwent functional exams, clinical labs, neuropsychological testing, and 3T magnetic resonance imaging of the brain. Fasting proteomic markers were examined for predicting mild cognitive impairment (MCI) and AD using support vector machine models. RESULTS: Data were examined from n = 1649 participants (Mexican American n = 866; non-Hispanic White n = 783). Proteomic profiles were highly accurate in detecting MCI (area under the curve [AUC] = 0.91) and dementia (AUC = 0.95). The proteomic profiles varied significantly between ethnic groups and disease state. Negative predictive value was excellent for ruling out MCI and dementia across ethnic groups. DISCUSSION: A blood-based screening tool can serve as a method for increasing access to state-of-the-art AD clinical research by bridging between community-based and clinic-based settings.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Vida Independente , Programas de Rastreamento , Americanos Mexicanos/estatística & dados numéricos , População Branca/estatística & dados numéricos , Idoso , Doença de Alzheimer/etnologia , Biomarcadores/sangue , Disfunção Cognitiva/sangue , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Seleção de Pacientes , Proteômica
6.
Dement Geriatr Cogn Disord ; 50(3): 266-273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34569492

RESUMO

INTRODUCTION: Alzheimer's disease (AD) is the most frequently occurring neurodegenerative disease; however, little work has been conducted examining biomarkers of AD among Mexican Americans. Here, we examined diffusion tensor MRI marker profiles for detecting mild cognitive impairment (MCI) and dementia in a multi-ethnic cohort. METHODS: 3T MRI measures of fractional anisotropy (FA) were examined among 1,636 participants of the ongoing community-based Health & Aging Brain among Latino Elders (HABLE) community-based study (Mexican American n = 851; non-Hispanic white n = 785). RESULTS: The FA profile was highly accurate in detecting both MCI (area under the receiver operating characteristic curve [AUC] = 0.99) and dementia (AUC = 0.98). However, the FA profile varied significantly not only between diagnostic groups but also between Mexican Americans and non-Hispanic whites. CONCLUSION: Findings suggest that diffusion tensor imaging markers may have a role in the neurodiagnostic process for detecting MCI and dementia among diverse populations.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Idoso , Envelhecimento , Doença de Alzheimer/diagnóstico por imagem , Anisotropia , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Americanos Mexicanos
7.
Dement Geriatr Cogn Disord ; 47(1-2): 68-78, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30861514

RESUMO

BACKGROUND: Mexican Americans are at increased risk of developing mild cognitive impairment (MCI) and Alzheimer's disease compared to non-Hispanic whites. This study sought to examine the relationship between vascular risk, depression, and cognition in Mexican American elders. METHODS: Data from 470 (390 normal controls, 80 MCI patients) Mexican Americans enrolled in the Health and Aging Brain among Latino Elders (HABLE) study were used. The cardiovascular risk was assessed by the Framingham Risk Score. Cognition was assessed with a neuropsychological battery, and depression was assessed based on scores from the Geriatric Depression Scale (GDS). ANOVAs were utilized to determine the differences in neuropsychological scores of normal controls with and without depression and CVD risk (low vs. high). Follow-up logistic regression was conducted to determine MCI risk. RESULTS: The results of this study indicated that comorbid depression and a high CVD risk were associated with poorer cognitive performance in Mexican Americans. Depressed women with high CVD risk were more likely to have executive dysfunction, language deficits, and poorer global cognition than nondepressed women with a high CVD risk. In Mexican American men, those with a high vascular risk and depression were more likely to have executive dysfunction and poorer immediate memory than the nondepressed high-risk group. Higher GDS scores (OR = 1.10; 95% CI 1.02-1.10, p = 0.001) and higher vascular risk scores (OR = 1.05; 95% CI 1.02-1.10, p = 0.001) significantly predicted MCI status in Mexican Americans. CONCLUSION: The results of this study indicated that comorbid depression and a high CVD risk were associated with poorer cognitive performance and increased risk of MCI in Mexican Americans.


Assuntos
Doença de Alzheimer , Doenças Cardiovasculares , Disfunção Cognitiva , Depressão , Americanos Mexicanos/psicologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/etnologia , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Cognição/fisiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etnologia , Disfunção Cognitiva/etiologia , Comorbidade , Depressão/diagnóstico , Depressão/etnologia , Depressão/etiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Prognóstico , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia
8.
Int Psychogeriatr ; 29(10): 1693-1699, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28629481

RESUMO

BACKGROUND: This study explored the combined impact of depression and inflammation on memory functioning among Mexican-American adults and elders. METHODS: Data were analyzed from 381 participants of the Health and Aging Brain study among Latino Elders (HABLE). Fasting serum samples were collected and assayed in duplicate using electrochemiluminesce on the SECTOR Imager 2400A from Meso Scale Discovery. Positive DepE (depression endophenotype) was codified as any score >1 on a five-point scale based on the GDS-30. Inflammation was determined by TNFα levels and categorized by tertiles (1st, 2nd, 3rd). WMS-III LMI and LMII as well as CERAD were utilized as measures of memory. ANOVAs examined group differences between positive DepE and inflammation tertiles with neuropsychological scale scores as outcome variables. Logistic regressions were used to examine level of inflammation and DepE positive status on the risk for MCI. RESULTS: Positive DepE as well as higher inflammation were both independently found to be associated with lower memory scores. Among DepE positive, those who were high in inflammation (3rd tertile) were found to perform significantly worse on WMS-III LM I (F = 4.75, p = 0.003), WMS-III LM II (F = 8.18, p < 0.001), and CERAD List Learning (F = 17.37, p < 0.001) when compared to those low on inflammation (1st tertile). The combination of DepE positive and highest tertile of inflammation was associated with increased risk for MCI diagnosis (OR = 6.06; 95% CI = 3.9-11.2, p < 0.001). CONCLUSION: Presence of elevated inflammation and positive DepE scores increased risk for worse memory among Mexican-American older adults. Additionally, the combination of DepE and high inflammation was associated with increased risk for MCI diagnosis. This work suggests that depression and inflammation are independently associated with worse memory among Mexican-American adults and elders; however, the combination of both increases risk for poorer memory beyond either alone.


Assuntos
Disfunção Cognitiva/etnologia , Depressão/etnologia , Inflamação/etnologia , Transtornos da Memória/etnologia , Americanos Mexicanos , Idoso , Disfunção Cognitiva/complicações , Estudos de Coortes , Depressão/complicações , Feminino , Humanos , Inflamação/complicações , Modelos Logísticos , Masculino , Transtornos da Memória/complicações , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Risco , Estados Unidos/epidemiologia
9.
Alzheimers Dement ; 13(1): 45-58, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27870940

RESUMO

The last decade has seen a substantial increase in research focused on the identification of blood-based biomarkers that have utility in Alzheimer's disease (AD). Blood-based biomarkers have significant advantages of being time- and cost-efficient as well as reduced invasiveness and increased patient acceptance. Despite these advantages and increased research efforts, the field has been hampered by lack of reproducibility and an unclear path for moving basic discovery toward clinical utilization. Here we reviewed the recent literature on blood-based biomarkers in AD to provide a current state of the art. In addition, a collaborative model is proposed that leverages academic and industry strengths to facilitate the field in moving past discovery only work and toward clinical use. Key resources are provided. This new public-private partnership model is intended to circumvent the traditional handoff model and provide a clear and useful paradigm for the advancement of biomarker science in AD and other neurodegenerative diseases.


Assuntos
Doença de Alzheimer/sangue , Biomarcadores/sangue , Comportamento Cooperativo , Parcerias Público-Privadas , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
10.
Alzheimers Dement ; 12(3): 292-323, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27012484

RESUMO

During the past decade, a conceptual shift occurred in the field of Alzheimer's disease (AD) considering the disease as a continuum. Thanks to evolving biomarker research and substantial discoveries, it is now possible to identify the disease even at the preclinical stage before the occurrence of the first clinical symptoms. This preclinical stage of AD has become a major research focus as the field postulates that early intervention may offer the best chance of therapeutic success. To date, very little evidence is established on this "silent" stage of the disease. A clarification is needed about the definitions and lexicon, the limits, the natural history, the markers of progression, and the ethical consequence of detecting the disease at this asymptomatic stage. This article is aimed at addressing all the different issues by providing for each of them an updated review of the literature and evidence, with practical recommendations.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Encéfalo/patologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Animais , Encéfalo/diagnóstico por imagem , Progressão da Doença , Humanos
11.
Int J Geriatr Psychiatry ; 30(8): 881-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25394326

RESUMO

OBJECTIVE: The objective was to evaluate in a cognitively normal population the utility of an endophenotype of the depression-cognition link previously shown to be related to cognitive functioning in mild cognitive impairment and Alzheimer's disease. METHODS: The data of 460 cognitively normal adults aged 32-92 years (M = 63.5, standard deviation = 9.24) from the Western Australian Memory Study with the Cross-national comparisons of the Cambridge Cognitive Examination-revised (CAMCOG-R) scores and 30-item Geriatric Depression Scale (GDS) scores were analyzed to determine the relationship between the five-item depressive endophenotype (DepE) scale drawn from the GDS and level of performance on a measure of cognitive functioning. RESULTS: For the entire sample, there was a nonsignificant trend toward a negative relationship between DepE and CAMCOG-R scores. When analyzed for those 65 years and older, there was a significant negative relationship between the two measures (p = 0.001) with DepE scores significantly increasing the risk for performing more poorly on the CAMCOG-R (odds ratio = 1.53). Analysis of data for those 70 years and older showed that DepE was the only predictor significantly related to poorer CAMCOG-R performance (p = 0.001). For the 70 years and older group, DepE scores significantly increased the risk of poorer CAMCOG-R scores (odds ratio = 2.23). Analysis of the entire sample on the basis of ApoEε4 carrier status revealed that DepE scores were significantly negatively related only to ApoEε4 noncarrier regardless of age. CONCLUSIONS: Elevated DepE scores are associated with poor neuropsychological performance among cognitively normal older adults. Use of the DepE may allow for the identification of a subset of older adults where depression is a primary factor in cognitive decline and who may benefit from antidepressant therapies.


Assuntos
Disfunção Cognitiva/diagnóstico , Transtorno Depressivo/complicações , Endofenótipos , Adulto , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Disfunção Cognitiva/genética , Disfunção Cognitiva/psicologia , Transtorno Depressivo/psicologia , Feminino , Psiquiatria Geriátrica , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Austrália Ocidental
12.
Alzheimers Dement ; 11(5): 561-78, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25443858

RESUMO

Current state-of-the-art diagnostic measures of Alzheimer's disease (AD) are invasive (cerebrospinal fluid analysis), expensive (neuroimaging) and time-consuming (neuropsychological assessment) and thus have limited accessibility as frontline screening and diagnostic tools for AD. Thus, there is an increasing need for additional noninvasive and/or cost-effective tools, allowing identification of subjects in the preclinical or early clinical stages of AD who could be suitable for further cognitive evaluation and dementia diagnostics. Implementation of such tests may facilitate early and potentially more effective therapeutic and preventative strategies for AD. Before applying them in clinical practice, these tools should be examined in ongoing large clinical trials. This review will summarize and highlight the most promising screening tools including neuropsychometric, clinical, blood, and neurophysiological tests.


Assuntos
Doença de Alzheimer/diagnóstico , Testes Diagnósticos de Rotina/métodos , Diagnóstico Precoce , Doença de Alzheimer/sangue , Doença de Alzheimer/complicações , Depressão/etiologia , Testes Diagnósticos de Rotina/normas , Eletrofisiologia , Olho/fisiopatologia , Marcha/fisiologia , Humanos , Transtornos da Memória/etiologia
13.
Alzheimers Dement ; 11(5): 549-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25282381

RESUMO

The lack of readily available biomarkers is a significant hindrance toward progressing to effective therapeutic and preventative strategies for Alzheimer's disease (AD). Blood-based biomarkers have potential to overcome access and cost barriers and greatly facilitate advanced neuroimaging and cerebrospinal fluid biomarker approaches. Despite the fact that preanalytical processing is the largest source of variability in laboratory testing, there are no currently available standardized preanalytical guidelines. The current international working group provides the initial starting point for such guidelines for standardized operating procedures (SOPs). It is anticipated that these guidelines will be updated as additional research findings become available. The statement provides (1) a synopsis of selected preanalytical methods utilized in many international AD cohort studies, (2) initial draft guidelines/SOPs for preanalytical methods, and (3) a list of required methodological information and protocols to be made available for publications in the field to foster cross-validation across cohorts and laboratories.


Assuntos
Doença de Alzheimer/sangue , Biomarcadores/sangue , Guias como Assunto/normas , Doença de Alzheimer/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Humanos
14.
Dement Geriatr Cogn Disord ; 38(5-6): 300-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25011444

RESUMO

BACKGROUND: Neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) are a major factor in nursing home placement and a primary cause of stress for caregivers. Elevated cholesterol has been linked to psychiatric disorders and has been shown to be a risk factor for AD and to impact disease progression. The present study investigated the relationship between cholesterol and NPS in AD. METHODS: Data on cholesterol and NPS from 220 individuals (144 females, 76 males) with mild-to-moderate AD from the Texas Alzheimer's Research and Care Consortium (TARCC) cohort were analyzed. The total number of NPS and symptoms of hyperactivity, psychosis, affect and apathy were evaluated. Groups based on total cholesterol (TC; ≥200 vs. <200 mg/dl) were compared with regard to NPS. The impact of gender was also assessed. RESULTS: Individuals with high TC had lower MMSE scores as well as significantly more NPS and more symptoms of psychosis. When stratified by gender, males with high TC had significantly more NPS than females with high TC or than males or females with low TC. CONCLUSION: The role of elevated cholesterol in the occurrence of NPS in AD appears to be gender and symptom specific. A cross-validation of these findings will have implications for possible treatment interventions, especially for males with high TC.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/psicologia , Colesterol/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Texas
15.
Dement Geriatr Cogn Disord ; 37(1-2): 45-57, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24107792

RESUMO

BACKGROUND: Prior work on the link between blood-based biomarkers and cognitive status has largely been based on dichotomous classifications rather than detailed neuropsychological functioning. The current project was designed to create serum-based biomarker algorithms that predict neuropsychological test performance. METHODS: A battery of neuropsychological measures was administered. Random forest analyses were utilized to create neuropsychological test-specific biomarker risk scores in a training set that were entered into linear regression models predicting the respective test scores in the test set. Serum multiplex biomarker data were analyzed on 108 proteins from 395 participants (197 Alzheimer patients and 198 controls) from the Texas Alzheimer's Research and Care Consortium. RESULTS: The biomarker risk scores were significant predictors (p < 0.05) of scores on all neuropsychological tests. With the exception of premorbid intellectual status (6.6%), the biomarker risk scores alone accounted for a minimum of 12.9% of the variance in neuropsychological scores. Biomarker algorithms (biomarker risk scores and demographics) accounted for substantially more variance in scores. Review of the variable importance plots indicated differential patterns of biomarker significance for each test, suggesting the possibility of domain-specific biomarker algorithms. CONCLUSIONS: Our findings provide proof of concept for a novel area of scientific discovery, which we term 'molecular neuropsychology'.


Assuntos
Algoritmos , Biomarcadores/sangue , Neuropsicologia/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/sangue , Doença de Alzheimer/psicologia , Cognição/fisiologia , Estudos de Coortes , Feminino , Humanos , Inteligência , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
16.
Environ Res ; 130: 59-69, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24559533

RESUMO

Exposure to arsenic causes many diseases. Most Americans in rural areas use groundwater for drinking, which may contain arsenic above the currently allowable level, 10µg/L. It is cost-effective to estimate groundwater arsenic levels based on data from wells with known arsenic concentrations. We compared the accuracy of several commonly used interpolation methods in estimating arsenic concentrations in >8000 wells in Texas by the leave-one-out-cross-validation technique. Correlation coefficient between measured and estimated arsenic levels was greater with inverse distance weighted (IDW) than kriging Gaussian, kriging spherical or cokriging interpolations when analyzing data from wells in the entire Texas (p<0.0001). Correlation coefficient was significantly lower with cokriging than any other methods (p<0.006) for wells in Texas, east Texas or the Edwards aquifer. Correlation coefficient was significantly greater for wells in southwestern Texas Panhandle than in east Texas, and was higher for wells in Ogallala aquifer than in Edwards aquifer (p<0.0001) regardless of interpolation methods. In regression analysis, the best models are when well depth and/or elevation were entered into the model as covariates regardless of area/aquifer or interpolation methods, and models with IDW are better than kriging in any area/aquifer. In conclusion, the accuracy in estimating groundwater arsenic level depends on both interpolation methods and wells' geographic distributions and characteristics in Texas. Taking well depth and elevation into regression analysis as covariates significantly increases the accuracy in estimating groundwater arsenic level in Texas with IDW in particular.


Assuntos
Arsênio/análise , Monitoramento Ambiental/métodos , Água Subterrânea/química , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Análise de Regressão , Texas
17.
Age Ageing ; 43(3): 364-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24321843

RESUMO

OBJECTIVE: cardiovascular burden is considered a risk factor for the development of cognitive dysfunction and dementia. While this link is well established in the literature, implementing this work in primary care settings remains a challenge. The goal of this study is to examine the utility of the Hachinski Ischemic Scale (HIS) in identifying cognitive dysfunction and diagnosis of mild cognitive impairment (MCI) in an ethnically diverse sample. METHODS: data were analysed on 517 participants (211 Mexican Americans and 306 non-Hispanic Whites) recruited from Project FRONTIER, a study of rural health. Neuropsychological measures were utilised to assess for cognitive functioning. RESULTS: among non-Hispanic Whites, HIS scores were significantly related to poorer performance on tasks of global cognition [B (SE) = -0.13 (0.06), P = 0.02], immediate memory [B (SE) = -0.85 (0.26), P < 0.001], attention [B (SE) = -1.6 (0.36), P < 0.001] and executive functioning [B (SE) = 0.46 (0.12), P < 0.001], and significantly predicted diagnosis of MCI [odds ratio (OR) = 1.4; 95% confidence interval (CI) = 1.2-1.6]. For Mexican Americans, HIS scores were significantly related to immediate memory [B (SE) = -0.78 (0.28), P = 0.01], attention [B (SE) = -0.74 (0.36), P = 0.04] and executive functioning [B (SE) = 0.37 (0.14), P = 0.01]; however, HIS scores were not significantly related to diagnosis of MCI in Mexican Americans (OR = 1.2, 95% CI = 0.96-1.4, P = 0.116). CONCLUSION: HIS scores were related to cognitive functioning; however, these results differed by ethnicity. It is possible that these findings indicate that vascular factors may increase risk for MCI among non-Hispanic Whites but not for Mexican Americans. These findings are consistent with past research that suggests risk factors for MCI may differ by ethnicity.


Assuntos
Transtornos Cognitivos , Cognição/fisiologia , Demência , Doenças Vasculares , Idoso , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etnologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Demência/diagnóstico , Demência/etnologia , Demência/etiologia , Demência/fisiopatologia , Função Executiva , Feminino , Humanos , Testes de Inteligência , Masculino , Americanos Mexicanos , Testes Neuropsicológicos , Prognóstico , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia , Doenças Vasculares/complicações , Doenças Vasculares/diagnóstico , Doenças Vasculares/etnologia , Doenças Vasculares/psicologia , Pesos e Medidas , População Branca
18.
Environ Health ; 13(1): 15, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24621105

RESUMO

BACKGROUND: The aim was to examine the link between low-level arsenic exposure and cognitive functioning, and the potential role of a single nucleotide polymorphism (SNP A35991G, rs10748835) of the AS3MT gene in modifying this link. METHODS: Data were analyzed on 526 participants from Project FRONTIER. Hierarchical linear regressions were created with neuropsychological raw index scores as the outcome variable and arsenic exposure and AS3MT SNP as different predictor variables. RESULTS: Within the total sample, arsenic exposure was negatively associated with language (p < 0.001) and executive functioning (p < 0.001). Among those with the AA genotype of the AS3MT gene, arsenic levels were negatively associated with language (p < 0.001), attention (p = 0.01), and executive functioning (p = 0.04). Among those with the AG genotype, arsenic levels were positively associated with immediate (p = 0.04) and delayed memory (p < 0.001) and negatively associated with executive functioning (p = 0.03). Among those with the GG genotype, arsenic levels were negatively associated with visuospatial functioning (p = 0.02). CONCLUSIONS: Low-level arsenic exposure is associated with cognitive functioning; however, this association is modified by an AS3MT gene.


Assuntos
Arsênio/toxicidade , Cognição/efeitos dos fármacos , Metiltransferases/genética , Poluentes Químicos da Água/toxicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Arsênio/análise , Atenção/efeitos dos fármacos , Monitoramento Ambiental , Função Executiva/efeitos dos fármacos , Humanos , Memória/efeitos dos fármacos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Polimorfismo de Nucleotídeo Único , População Rural , Fala/efeitos dos fármacos , Texas , Poluentes Químicos da Água/análise
19.
Alzheimers Dement ; 10(1): 115-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23850333

RESUMO

Treatment of Alzheimer's disease (AD) is significantly hampered by the lack of easily accessible biomarkers that can detect disease presence and predict disease risk reliably. Fluid biomarkers of AD currently provide indications of disease stage; however, they are not robust predictors of disease progression or treatment response, and most are measured in cerebrospinal fluid, which limits their applicability. With these aspects in mind, the aim of this article is to underscore the concerted efforts of the Blood-Based Biomarker Interest Group, an international working group of experts in the field. The points addressed include: (1) the major challenges in the development of blood-based biomarkers of AD, including patient heterogeneity, inclusion of the "right" control population, and the blood-brain barrier; (2) the need for a clear definition of the purpose of the individual markers (e.g., prognostic, diagnostic, or monitoring therapeutic efficacy); (3) a critical evaluation of the ongoing biomarker approaches; and (4) highlighting the need for standardization of preanalytical variables and analytical methodologies used by the field.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Biomarcadores/sangue , Progressão da Doença , Humanos
20.
JAMA Netw Open ; 7(9): e2431180, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39226056

RESUMO

Importance: Determining the influence of race and ethnicity on change in cognitive test performance has significant implications for clinical practice and research in populations at risk for Alzheimer disease. Objective: To evaluate the significance of race and ethnicity in predicting longitudinal cognitive test performance and to develop models to support evidence-based practice. Design, Setting, and Participants: This prognostic study included baseline and 24-month follow-up data that were obtained from the Health and Aging Brain Study-Health Disparities (HABS-HD) study, an ongoing longitudinal observational study of aging and dementia in a multiracial, multiethnic cohort. Participants included community-dwelling adults and elders living in the Dallas and Fort Worth metropolitan area who were Hispanic and non-Hispanic adults older than the age of 50 years and were cognitively unimpaired. Exposure: The primary exposure of interest was time, measured in months. Main Outcomes and Measures: Demographic variables included age, sex, education, and race and ethnicity. Cognitive domains included attention and working memory, processing speed, language, memory, and executive functioning. Linear regression models predicted follow-up performance from baseline performance and demographic variables for 13 commonly used neuropsychological tests. Follow-up testing was the primary outcome for all domains. Raw scores from 13 standardized tests were used for analyses. Results: This study included 799 adults who were cognitively unimpaired (352 Hispanic individuals [44.1%]; 447 non-Hispanic individuals [55.9%]; 524 female [65.6%]; mean [SD] age, 65.4 [8.1] years). In the regression models, all 13 follow-up scores were significantly predicted from their respective baseline scores and demographic variables. Baseline performance and education were the most consistent predictors of follow-up scores, contributing to all 13 models. Age was significantly associated with follow-up in 11 models, and sex was significant in 5 models. Race and ethnicity contributed to 10 of 13 models, with Hispanic participants predicted to have poorer follow-up scores than their non-Hispanic White counterparts on each test. Conclusions and Relevance: In this longitudinal study of cognitive change in Hispanic and non-Hispanic older adults who were cognitively unimpaired, standardized regression-based models were influenced by multiple demographic variables, including race and ethnicity. These findings highlight the importance of including race and ethnicity in such cognitive change models. This ability to accurately predict cognitive change is expected to become increasingly important as clinical practice and clinical trials need to become more diverse and culturally appropriate in this burgeoning global medical and societal crisis.


Assuntos
Cognição , Hispânico ou Latino , Testes Neuropsicológicos , Humanos , Feminino , Masculino , Hispânico ou Latino/estatística & dados numéricos , Hispânico ou Latino/psicologia , Idoso , Pessoa de Meia-Idade , Estudos Longitudinais , Testes Neuropsicológicos/estatística & dados numéricos , Disfunção Cognitiva/etnologia , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Envelhecimento/etnologia
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