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1.
Georgian Med News ; (294): 83-87, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687955

RESUMO

The aim of the research was to investigate the relationship between cerebral microembolization and the development of postoperative cognitive impairment in patients after coronary artery bypass grafting with and without prophylactic administration of nitroglycerin at the end of artificial blood circulation. The study included 72 patients (43 male and 29 female) who had ACBPS using an ABCA. The patients were randomized into two clinical groups. The number of patients in the control group was 34 patients, in the study group - 38 patients. The study of the cognitive sphere was performed using a battery of clinical tests that included MSA and MMSE scales, Trail-making test, Grooved Pageboard, fine hands-motor test, 10 words test by AR Luria, Wexler's test, Schultz tables. The assessment was carried out on a day before the intervention and on the fifth day after the surgical intervention. It was shown that by all patients undergoing aorto-coronary bypass syrgery microembolization within the cerebral blood flow had been determined. The vast majority of microemboli is formed at the beginning of artificial blood circulation, at the moment of clamping aorta, as well as during the restoration of effective cardiac activity. Intraoperative microembolization of cerebral blood flow in excess of 750 microemboli leads to clinically significant deterioration of the brain functions in the early postoperative period. When used as a peripheral vasodilator, nitroglycerin, at a dose of 8-10 µg/kg*min in high (120-130%) volume perfusion rate, decreases the number of microemboluses in the basin of СМА by 2.4%.


Assuntos
Aorta/diagnóstico por imagem , Substitutos Sanguíneos , Ponte Cardiopulmonar/efeitos adversos , Disfunção Cognitiva/etiologia , Ponte de Artéria Coronária/efeitos adversos , Embolia Intracraniana/psicologia , Infarto do Miocárdio/cirurgia , Idoso , Idoso de 80 Anos ou mais , Ponte Cardiopulmonar/métodos , Circulação Cerebrovascular , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Ponte de Artéria Coronária/métodos , Feminino , Humanos , Embolia Intracraniana/complicações , Embolia Intracraniana/diagnóstico por imagem , Embolia Intracraniana/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle
2.
Medicine (Baltimore) ; 98(45): e17824, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702636

RESUMO

The hippocampus is one of the earliest sites involved in the pathology of Alzheimer's disease (AD). Therefore, we specifically investigated the sensitivity and specificity of hippocampal volume and glucose metabolism in patients being evaluated for AD, using automated quantitative tools (NeuroQuant - magnetic resonance imaging [MRI] and Scenium - positron emission tomography [PET]) and clinical evaluation.This retrospective study included adult patients over the age of 45 years with suspected AD, who had undergone fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET-CT) and MRI. FDG-PET-CT images were analyzed both qualitatively and quantitatively. In quantitative volumetric MRI analysis, the percentage of the total intracranial volume of each brain region, as well as the total hippocampal volume, were considered in comparison to an age-adjusted percentile. The remaining brain regions were compared between groups according to the final diagnosis.Thirty-eight patients were included in this study. After a mean follow-up period of 23 ±â€Š11 months, the final diagnosis for 16 patients was AD or high-risk mild cognitive impairment (MCI). Out of the 16 patients, 8 patients were women, and the average age of all patients was 69.38 ±â€Š10.98 years. Among the remaining 22 patients enrolled in the study, 14 were women, and the average age was 67.50 ±â€Š11.60 years; a diagnosis of AD was initially excluded, but the patients may have low-risk MCI. Qualitative FDG-PET-CT analysis showed greater accuracy (0.87), sensitivity (0.76), and negative predictive value (0.77), when compared to quantitative PET analysis, hippocampal MRI volumetry, and specificity. The positive predictive value of FDG-PET-CT was similar to the MRI value.The performance of FDG-PET-CT qualitative analysis was significantly more effective compared to MRI volumetry. At least in part, this observation could corroborate the sequential hypothesis of AD pathophysiology, which posits that functional changes (synaptic dysfunction) precede structural changes (atrophy).


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Fluordesoxiglucose F18/metabolismo , Hipocampo/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/metabolismo , Diagnóstico Precoce , Feminino , Glucose/metabolismo , Hipocampo/metabolismo , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Medicine (Baltimore) ; 98(40): e17127, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31577703

RESUMO

To investigate the functional connectome alterations in cerebral small-vessel disease (CSVD) patients with thalamus lacunes and its relation to cognitive impairment.This case-control study was approved by the local research ethics committee, and all participants provided informed consent. There were 14 CSVD patients with thalamus lacunes (CSVDw.), 27 without (CSVDwo.), and 34 healthy controls (HC) recruited matched for age, sex, and education to undergo a 3T resting-state functional MR examination. The whole-brain functional connectome was constructed by thresholding the Pearson correlation matrices of 90 brain regions, and the topologic properties were analyzed by using graph theory approaches. Networks were compared between CSVD patients and HC, and associations between network measures and cognitive function were tested.Compared with HC, the functional connectome in CSVDw. patients showed abnormalities at the global level and at the nodal level (P < .05, false discovery rate corrected). The network-based statistics method identified a significantly altered network consisting 6 nodes and 13 connections. Among all the 13 connections, only two connections had significant correlation with episodic memory (EM) and processing speed (PS) respectively (P < .05). The CSVDwo. patients showed no significant network alterations relative to controls (P > .05).The configurations of brain functional connectome in CSVDw. patients were perturbed but not obvious for those without, and correlated with the mild cognitive impairment, especially for EM and PS. This study suggested that lacunes on thalamus played a vital role in mediating the neural functional changes of CSVD patients.


Assuntos
Doenças de Pequenos Vasos Cerebrais/patologia , Disfunção Cognitiva/patologia , Conectoma , Leucoencefalopatias/patologia , Tálamo/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Estudos Transversais , Escolaridade , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Leucoencefalopatias/complicações , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Índice de Gravidade de Doença , Fatores Sexuais , Tálamo/diagnóstico por imagem
4.
Clin Interv Aging ; 14: 1631-1642, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571843

RESUMO

Purpose: Recent studies have found associations of increased brain amyloid beta (Aß) accumulation and several abnormal sleep-wake patterns, including shorter latency and increased fragmentation in preclinical Alzheimer's disease (AD). There is little known about the relationship between sleep and tau. The objective of this study was to understand the associations of both tau and Aß with early signs of sleep and night-time behavior changes in clinically normal elderly adults. Specifically, we have addressed the question of how informant-based subjective sleep reports are linked to regional [18F]flortaucipir and [18F]florbetapir uptake. Methods: Imaging and behavioral data from 35 subjects were obtained from the Alzheimer's Disease Neuroimaging Initiative. The Neuropsychiatric Inventory Sleep (NPI-sleep) Questionnaire was used to assess the sleep and night-time behavior changes. Regional tau-positron emission tomography (PET) (entorhinal, brainstem) and Aß-PET (posterior cingulate, precuneus, medial orbitofrontal) uptake values were calculated. A series of linear regression analyses were used to determine the combination of sleep symptoms that built the best models to predict each pathology. Results: Informant-based reports of abnormal night-time behavior (NPI questions k3, k5, and k8) were significantly associated with increased entorhinal tau and Aß (all regions) accumulation. Interestingly, informant-based reports of sleep deficiencies without abnormal nigh-time activity (NPI questions k1, k2, and k6) were negatively associated with entorhinal tau burden. Conclusion: Detection of abnormal night-time behaviors (wandering, pacing, other inappropriate activities) by family members indicates early signs of both AD pathologies and may encourage the affected individuals to seek help by health care providers for detailed cognitive/neurobehavioral assessments.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Córtex Entorrinal/metabolismo , Sono , Proteínas tau/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Compostos de Anilina , Sintomas Comportamentais , Carbolinas , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Córtex Entorrinal/diagnóstico por imagem , Etilenoglicóis , Feminino , Humanos , Masculino , Neuroimagem , Tomografia por Emissão de Pósitrons/métodos , Inquéritos e Questionários , Fatores de Tempo
5.
Postgrad Med ; 131(7): 501-508, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31483196

RESUMO

Objectives: Aiginition Longitudinal Biomarker Investigation Of Neurodegeneration (ALBION) is a longitudinal ongoing study initiated in 2018 that takes place in the Cognitive Disorders Clinic of Aiginition Hospital of the National and Kapodistrian University of Athens. Its aim is to address several research questions concerning the preclinical and prodromal stage of Alzheimer's disease and explore potential markers for early detection, prediction, and primary prevention of dementia. Methods: We here present the design and the preliminary baseline characteristics of ALBION. The sample of our study consists of people aged over 50 who are concerned about their memory but are cognitively normal (CN) or have mild cognitive deficits. Each participant undergoes an extensive assessment including several demographic, medical, social, environmental, clinical, nutritional, neuropsychological determinants and lifestyle activities. Furthermore, we are collecting data from portable devices, neuroimaging techniques and biological samples (blood, stools, CSF). All participants are assessed annually for a period of 10 years. Results: In total, 47 participants have completed the initial evaluation up to date and are divided in two groups, CN individuals (N = 26) and MCI patients (N = 21), based on their cognitive status. The participants are, on average, 64 years old, 46.3% of the sample is male with an average of 12.73 years of education. MCI patients report more comorbidities and have a lower score in the MMSE test. Regarding APOE status, 2 participants are ε4 homozygotes and 10 ε4 heterozygotes. CSF analyses (Aß42, Τ-tau, P-tau) revealed no differences between the two groups. Conclusion: The ALBION study offers an opportunity to explore preclinical dementia and identify new and tailored markers, particularly relating to lifestyle. Further investigation of these populations may provide a wider profile of the changes taking place in the preclinical phase of dementia, leading to potentially effective therapeutic and preventive strategies.


Assuntos
Doença de Alzheimer/prevenção & controle , Disfunção Cognitiva/metabolismo , Prevenção Primária , Sintomas Prodrômicos , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apolipoproteínas E/genética , Biomarcadores , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Diagnóstico Precoce , Eletroencefalografia , Feminino , Neuroimagem Funcional , Grécia , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Dados Preliminares , Proteínas tau/líquido cefalorraquidiano
6.
Neurology ; 93(14): e1348-e1359, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31484713

RESUMO

OBJECTIVE: To determine which pathologic process could be responsible for the acceleration of cognitive decline during the course of multiple sclerosis (MS), using longitudinal structural MRI, which was related to cognitive decline in relapsing-remitting MS (RRMS) and progressive MS (PMS). METHODS: A prospective cohort of 230 patients with MS (179 RRMS and 51 PMS) and 59 healthy controls was evaluated twice with 5-year (mean 4.9, SD 0.94) interval during which 22 patients with RRMS converted to PMS. Annual rates of cortical and deep gray matter atrophy as well as lesion volume increase were computed on longitudinal (3T) MRI data and correlated to the annual rate of cognitive decline as measured using an extensive cognitive evaluation at both time points. RESULTS: The deep gray matter atrophy rate did not differ between PMS and RRMS (-0.82%/year vs -0.71%/year, p = 0.11), while faster cortical atrophy was observed in PMS (-0.87%/year vs -0.48%/year, p < 0.01). Similarly, faster cognitive decline was observed in PMS compared to RRMS (p < 0.01). Annual cognitive decline was related to the rate of annual lesion volume increase in stable RRMS (r = -0.17, p = 0.03) to the rate of annual deep gray matter atrophy in converting RRMS (r = 0.50, p = 0.02) and annual cortical atrophy in PMS (r = 0.35, p = 0.01). CONCLUSIONS: These results indicate that cortical atrophy and cognitive decline accelerate together during the course of MS. Substrates of cognitive decline shifted from worsening lesional pathology in stable RRMS to deep gray matter atrophy in converting RRMS and to accelerated cortical atrophy in PMS only.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/psicologia , Adulto , Idoso , Atrofia/diagnóstico por imagem , Atrofia/epidemiologia , Atrofia/psicologia , Disfunção Cognitiva/epidemiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Estudos Prospectivos
7.
Postgrad Med ; 131(7): 533-538, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31478419

RESUMO

Introduction: Depression in patients with mild cognitive impairment (MCI) and dementia of the Alzheimer's type (AD) is associated with worse prognosis. Indeed, depressed MCI patients have worse cognitive performance and greater loss of gray-matter volume in several brain areas. To date, knowledge of the factors that can mitigate this detrimental effect is still limited. The aim of the present study was to understand in what way cognitive reserve/brain reserve and depression interact and are linked to regional atrophy in early stage AD. Methods: Depression was evaluated with the Patient Health Questionnaire-9 in 90 patients with early AD, and a cutoff of ≥ 5 was used to separate depressed (n = 44) from non-depressed (n = 46) patients. Each group was further stratified into high/low cognitive reserve/brain reserve. Cognitive reserve was calculated using years of education as proxy, while normalized parenchymal volumes were used to estimate brain reserve. Voxel-based morphometry was carried out to extract and analyze gray-matter maps. 2 × 2 ANCOVAs were run to test the effect of the reserve-by-depression interaction on gray matter. Age and hippocampal ratio were used as covariates. Composite indices of major cognitive domains were also analyzed with comparable models. Results: No reserve-by-depression interaction was found in the analytical models of gray matter. Depression was associated with less gray matter volume in the cerebellum and parahippocampal gyrus. The brain reserve-by-depression interaction was a significant predictor of executive functioning. Among those with high brain reserve, depressed patients had poorer executive skills. No significant results were found in association with cognitive reserve. Conclusion: These findings suggest that brain reserve may modulate the association between neurodegeneration and depression in patients with MCI and dementia of the AD type, influencing in particular executive functioning.


Assuntos
Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Reserva Cognitiva , Depressão/psicologia , Substância Cinzenta/diagnóstico por imagem , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Depressão/diagnóstico por imagem , Depressão/fisiopatologia , Feminino , Substância Cinzenta/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Giro Para-Hipocampal/diagnóstico por imagem , Giro Para-Hipocampal/patologia , Questionário de Saúde do Paciente
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(7): 805-812, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31413220

RESUMO

OBJECTIVE: To evaluate the white-matter integrity and its correlation with cognitive function in patients with mild cognitive impairment (MCI) complicated with lacunar infarctions (LI) by diffusion tensor imaging (DTI) of magnetic resonance (MR).
 Methods: Twenty-six patients with MCI were selected including 14 patients with combined LI and 12 patients without combined LI, and 16 healthy volunteers were recruited as normal control. All subjects completed cognitive function assessment and DTI sequence of MR. Factional anisotropy (FA) and mean diffusivity (MD) values among the MCI with LI group (MCI-LI), the MCI without LI group (MCI-non LI), and the normal control group (NC) were compared, and the correlation between DTI parameters and cognition was determined by multiple linear stepwise regression.
 Results: Compared with the MCI-non LI group, the FA values were significantly decreased (P<0.05) and MD values were significantly increased (P<0.05) in the white matter fiber bundles (such as the left hippocampus of the cingulate tract, the frontal fascicle of the corpus callosum, the right inferior frontal occipital fascicle, and the right superior longitudinal fascicle) in the MCI-LI group. In the MCI-LI group, the FA value of right cingulate gyrus was significantly correlated with Activity of Daily Living Scale (ADL) score (B=-50.2, 95% CI -77.7 to -22.7, P=0.003); the FA value of left anterior thalamic radiation (B=443.8, 95% CI 222.9 to 664.8, P=0.001) and MD value of left inferior longitudinal tract (B=-318.5, 95% CI -534.7 to -102.3, P=0.009) were significantly correlated with Wechsler digit symbol substitution (WDSS) score; the FA value of left superior temporal lobe longitudinal tract was significantly correlated with Backward Digit Span (BDSP) score (B=12.5, 95% CI 1.5 to 23.4, P=0.030).
 Conclusion: The integrity of white matter is significantly destroyed in MCI patients with LI than that in MCI patients without LI, and there is a correlation between cognitive function and DTI parameters in some white matter tracts in MCI patients with LI.


Assuntos
Disfunção Cognitiva , Acidente Vascular Cerebral Lacunar , Substância Branca , Anisotropia , Encéfalo , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Testes Neuropsicológicos
9.
Dement Geriatr Cogn Disord ; 47(4-6): 243-253, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31408858

RESUMO

BACKGROUND: Endothelial dysfunction and subsequent inflammation contribute to the development of vascular cognitive impairment (VCI). Soluble intercellular adhesion molecule-1 (sICAM-1) is upregulated in endothelial dysfunction and promotes an inflammatory response; however, the relationship between sICAM-1 and VCI remains equivocal. OBJECTIVE: To determine whether sICAM-1 contributes to the prediction of VCI. METHODS: Community-dwelling older adults (n = 172) from the "Cohort of Obesity, Sarcopenia and Frailty of Older Mexican Adults" (COSFOMA) study were identified as VCI or controls using standard neuropsychological evaluations and neuroimaging. sICAM-1 was quantified using ELISA, and multivariate logistic regression determined the association between sICAM-1 and VCI. RESULTS: A total of 31 VCI cases were identified. sICAM-1 was higher in VCI (VCI: 450.7 [241.6] ng/mL vs. controls: 296.9 [140.9] ng/mL). sICAM-1 concentrations above the 90th percentile (464.1 ng/mL) were associated with VCI group membership in all models (OR: 6.9, 95% CI: 1.1-42.2). The final saturated model explained 64% of the variance in VCI group membership. CONCLUSION: High concentrations of sICAM-1 are independently associated with VCI group membership. Efforts to further characterize the relationship between indices of endothelial dysfunction and pathological changes to the aging brain should be further pursued.


Assuntos
Biomarcadores/sangue , Disfunção Cognitiva/sangue , Demência Vascular/sangue , Molécula 1 de Adesão Intercelular/sangue , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Demência Vascular/diagnóstico por imagem , Demência Vascular/psicologia , Feminino , Idoso Fragilizado , Humanos , Vida Independente , Masculino , México , Neuroimagem , Testes Neuropsicológicos , Valor Preditivo dos Testes , Fatores Socioeconômicos , Regulação para Cima
10.
Indian J Med Res ; 149(4): 503-507, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31411174

RESUMO

Background & objectives: There is a paucity of literature on the cognitive profiles of vascular dementia (VaD) in India. The current study was undertaken to investigate the pattern of cognitive deficits in patients with VaD. Methods: Fifty patients fulfilling the Diagnostic and Statistical Manual of Mental Disorders-IV criteria of dementia and National Institute of Neurological Disorders and Stroke - Association Internationale pour la Recherche et l'Enseignement en Neurosciences criteria for VaD were assessed using Mini Mental State Examination, Kolkata Cognitive Screening Battery and other relevant tests including magnetic resonance imaging of brain. Results: Twenty patients had small vessel dementia, whereas the least common was haemorrhagic dementia in four patients. In patients with small vessel dementia, apart from memory, all patients had problem in attention and executive function, whereas 12 patients had visuoconstructional deficit and eight patients had language problem. In a total of 12 patients with large vessel dementia, apart from memory, executive dysfunction and visuoconstructional deficit were noted in 10 patients, whereas attention deficit was noted in eight patients. Attention was found to be more involved in small-vessel dementia than large-vessel dementia though all had memory impairment (P<0.01). Interpretation & conclusions: Small vessel dementia was the commonest subtype of VaD in our study. Memory, attention and executive functions were predominantly affected in patients with VaD. Attention was significantly more involved in small vessel dementia than large vessel dementia. Further studies with large sample size need to be done in different regions of the country.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Transtornos Cognitivos/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Demência Vascular/fisiopatologia , Idoso , Vasos Sanguíneos/patologia , Encéfalo/fisiopatologia , Transtornos Cognitivos/complicações , Transtornos Cognitivos/diagnóstico por imagem , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico por imagem , Demência Vascular/complicações , Demência Vascular/diagnóstico por imagem , Feminino , Humanos , Índia/epidemiologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
11.
Zhonghua Nei Ke Za Zhi ; 58(9): 662-667, 2019 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-31461817

RESUMO

Objective: To investigate the correlation of functional connectivity (FC) and the integrity of connective fibres between hippocampus and thalamus in Alzheimer's disease(AD) and amnestic mild cognitive impairment (aMCI). Methods: Both resting-state functional magnetic resonance imaging (rs-fMRI) and diffusion tensor imaging (DTI) data of 40 AD patients, 37 aMCI patients and 41 normal control subjects matching with age and educational level were collected. These subjects were all recruited from outpatient Department of Neurology in the Second Medical Center of Chinese PLA General Hospital, as well as poster, from May 2016 to January 2018. The FC strength between bilateral hippocampus and thalamus, as well as the parameters representing integrity of connective fibres, including fractional anisotropy (FA) and mean diffusivity(MD),were analyzed. Also, the correlations between FC strength and FA or MD strength were analyzed in the study. Results: Compared to that of normal control subjects, the FC strength between billateral hippocampus and thalamus in patients with AD, aMCI were not significantly different(P>0.05). The integrity of bilateral connective fibres between hippocampus and thalamus were damaged in AD patients when compared to normal control subjects(P<0.01). A positive correlation of connective fibres integrity with FC strength between hippocampus and thalamus was found in the left side(r=0.25,P<0.05) but rather in the right side. Conclusion: In AD and aMCI patients, structural connectivity between left hippocampus and thalamus affects the functional connectivity between them.


Assuntos
Doença de Alzheimer/fisiopatologia , Amnésia/complicações , Disfunção Cognitiva/fisiopatologia , Hipocampo/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Tálamo/diagnóstico por imagem , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/patologia , Estudos de Casos e Controles , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Humanos , Imagem por Ressonância Magnética/métodos
13.
Medicine (Baltimore) ; 98(29): e16509, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335725

RESUMO

To evaluate the use of amyloid-positron emission tomography (PET) in routine clinical practice, in a selected population with cognitive impairment that meets appropriate use criteria (AUC).A multicenter, observational, prospective case-series study of 211patients from 2 level-3 hospitals who fulfilled clinical AUC for amyloid-PET scan in a naturalistic setting. Certainty degree was evaluated using a 5-point Likert scale: 0 (very low probability); 1 (low probability); 2 (intermediate probability); 3 (high probability); and 4 (practically sure), before and after amyloid PET. The treatment plan was considered as cognition-specific or noncognition-specific.Amyloid-PET was positive in 118 patients (55.9%) and negative in 93 patients (44.1%). Diagnostic prescan confidence according amyloid-PET results showed that in both, negative and positive-PET subgroup, the most frequent category was intermediate probability (45.7% and 55.1%, respectively). After the amyloid-PET, the diagnostic confidence showed a very different distribution, that was, in the negative-PET group the most frequent categories are very unlikely (70.7%) and unlikely (29.3%), while in the positive-PET group were very probable (57.6%) and practically sure (39%). Only in 14/211 patients (6.6%) the result of the amyloid-PET did not influence the diagnostic confidence, while in 194 patients (93.4%), the diagnostic confidence improved significantly after amyloid-PET results. The therapeutic intention was modified in 93 patients (44.1%). Specific treatment for Alzheimer disease was started, before amyloid-PET, in 80 patients (37.9%).This naturalistic study provides evidence that the implementation of amyloid-PET is associated with a significant improvement in diagnostic confidence and has a high impact on the therapeutic management of patients with mild cognitive impairment fulfilled clinical AUC.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Placa Amiloide/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Idoso , Doença de Alzheimer/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Clin Interv Aging ; 14: 1167-1175, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303750

RESUMO

Purpose: We assessed the effect of home-based cognitive intervention (HCI) on cognitive function along with brain metabolism by 18F-FDG PET in patients with amnestic MCI (aMCI). Patients and methods: Fifty-seven patients with aMCI from three hospitals were randomized (30 HCI, 27 control). For 12 weeks, subjects received HCI. Thirty-two subjects (15 HCI, 17 control) underwent brain 18-F-FDG-PET imaging at baseline and at 12 and 24 weeks. Results: The HCI group showed significant improvement in the scores of the Controlled Oral Word Association Test (COWAT) 12 and at 24 weeks. Significant brain metabolic changes by 18F-FDG PET were not observed. Conclusion: The current study suggests that HCI was effective in improving general cognition along with frontal executive function in patients with aMCI.


Assuntos
Cognição , Terapia Cognitivo-Comportamental/métodos , Disfunção Cognitiva/reabilitação , Idoso , Encéfalo/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Função Executiva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos , Resultado do Tratamento
15.
Med Biol Eng Comput ; 57(9): 1961-1983, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301007

RESUMO

In this paper, we propose a network analysis-based approach to help experts in their analyses of subjects with mild cognitive impairment (hereafter, MCI) and Alzheimer's disease (hereafter, AD) and to investigate the evolution of these subjects over time. The inputs of our approach are the electroencephalograms (hereafter, EEGs) of the patients to analyze, performed at a certain time and, again, 3 months later. Given an EEG of a subject, our approach constructs a network with nodes that represent the electrodes and edges that denote connections between electrodes. Then, it applies several network-based techniques allowing the investigation of subjects with MCI and AD and the analysis of their evolution over time. (i) A connection coefficient, supporting experts to distinguish patients with MCI from patients with AD; (ii) A conversion coefficient, supporting experts to verify if a subject with MCI is converting to AD; (iii) Some network motifs, i.e., network patterns very frequent in one kind of patient and absent, or very rare, in the other. Patients with AD, just by the very nature of their condition, cannot be forced to stay motionless while undergoing examinations for a long time. EEG is a non-invasive examination that can be easily done on them. Since AD and MCI, if prodromal to AD, are associated with a loss of cortical connections, the adoption of network analysis appears suitable to investigate the effects of the progression of the disease on EEG. This paper confirms the suitability of this idea Graphical Abstract Ability of our proposed model to distinguish a control subject from a patient with MCI and a patient with AD. Blue edges represent strong connections among the corresponding brain areas; red edges denote middle connections, whereas green edges indicate weak connections. In the control subject (at the top), most connections are blue. In the patient with MCI (at the middle), most connections are red and green. In the patient with AD (at the bottom), most connections are either absent or green. .


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Análise por Conglomerados , Tomada de Decisões Assistida por Computador , Feminino , Humanos , Masculino , Modelos Neurológicos , Sensibilidade e Especificidade
16.
Magn Reson Imaging ; 62: 167-173, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31279772

RESUMO

An inventive scheme for automated tissue segmentation and classification is offered in this paper using Fast Discrete Wavelet Transform (DWT)/Band Expansion Process (BEP), Kernel-based least squares Support Vector Machine (KLS-SVM) and F-score, backed by Principal Component Analysis (PCA). Using input as T1, T2 and Proton Density (PD) scans of patients, CSF (Cerebrospinal Fluid), WM (White matter) and GM (Gray matter) are afforded as output, which act as hallmark for brain atrophy and thus sustaining in diagnosis of Alzheimer's disease (AD) from Mild Cognitive Impairment (MCI) and Healthy Controls (HC). The blending of BEP features from DWT and texture features from Gray Level Co-occurrence Matrix (GLC) promises to be a savior in atrophy revelation of the segmented tissues. Data used for evaluation of this study is taken from the ADNI database that encloses T1-weighted s-MRI (Structural Magnetic Imaging Resonance) scans of 158 patients with AD and 145 HC. Preprocessing steps unearthed five parameters for classification (i.e. cortical thickness, curvature, gray matter volume, surface area, and sulcal depth), in the preliminary step. For challenging the classifier performance, ROC (Receiver operating characteristics) curves are painted and the SVM classifiers of two-dimensional spaces took the top two important features as classification features for separating HC and AD to the maximum extent. The final results revealed that Fast DWT + F-Score + PCA + KLS-SVM + Poly Kernel is giving 100% tissue classification accuracy for test samples under consideration with only 7 input features.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Atrofia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Imagem por Ressonância Magnética , Idoso , Algoritmos , Doença de Alzheimer/patologia , Atrofia/patologia , Encéfalo/patologia , Mapeamento Encefálico , Disfunção Cognitiva/patologia , Reações Falso-Positivas , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão , Análise de Componente Principal , Curva ROC , Máquina de Vetores de Suporte , Análise de Ondaletas
17.
Neurology ; 93(4): e334-e346, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31266904

RESUMO

OBJECTIVE: To investigate the relationship between cognitive reserve (CR) and clinical progression across the Alzheimer disease (AD) spectrum. METHODS: We selected 839 ß-amyloid (Aß)-positive participants with normal cognition (NC, n = 175), mild cognitive impairment (MCI, n = 437), or AD dementia (n = 227) from the Alzheimer's Disease Neuroimaging Initiative (ADNI). CR was quantified using standardized residuals (W scores) from a (covariate-adjusted) linear regression with global cognition (13-item Alzheimer's Disease Assessment Scale-cognitive subscale) as an independent variable of interest, and either gray matter volumes or white matter hyperintensity volume as dependent variables. These W scores, reflecting whether an individual's degree of cerebral damage is lower or higher than clinically expected, were tested as predictors of diagnostic conversion (i.e., NC to MCI/AD dementia, or MCI to AD dementia) and longitudinal changes in memory (ADNI-MEM) and executive functions (ADNI-EF). RESULTS: The median follow-up period was 24 months (interquartile range 6-42). Corrected for age, sex, APOE4 status, and baseline cerebral damage, higher gray matter volume-based W scores (i.e., greater CR) were associated with a lower diagnostic conversion risk (hazard ratio [HR] 0.22, p < 0.001) and slower decline in memory (ß = 0.48, p < 0.001) and executive function (ß = 0.67, p < 0.001). Stratified by disease stage, we found similar results for NC (diagnostic conversion: HR 0.30, p = 0.038; ADNI-MEM: ß = 0.52, p = 0.028; ADNI-EF: ß = 0.42, p = 0.077) and MCI (diagnostic conversion: HR 0.21, p < 0.001; ADNI-MEM: ß = 0.43, p = 0.003; ADNI-EF: ß = 0.59, p < 0.001), but opposite findings (i.e., more rapid decline) for AD dementia (ADNI-MEM: ß = -0.91, p = 0.002; ADNI-EF: ß = -0.77, p = 0.081). CONCLUSIONS: Among Aß-positive individuals, greater CR related to attenuated clinical progression in predementia stages of AD, but accelerated cognitive decline after the onset of dementia.


Assuntos
Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Reserva Cognitiva , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Compostos de Anilina , Estudos de Casos e Controles , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Meios de Contraste , Progressão da Doença , Etilenoglicóis , Função Executiva , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Memória , Pessoa de Meia-Idade , Tamanho do Órgão , Fragmentos de Peptídeos/líquido cefalorraquidiano , Tiazóis , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
18.
Neurology ; 93(4): e322-e333, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31289148

RESUMO

OBJECTIVE: To determine the time required for a preclinical Alzheimer disease population to decline in a meaningful way, use estimates of decline to update previous clinical trial design assumptions, and identify factors that modify ß-amyloid (Aß)-related decline. METHODS: In 1,120 cognitively unimpaired individuals from 3 international cohorts, we estimated the relationship between Aß status and longitudinal changes across multiple cognitive domains and assessed interactions between Aß and baseline factors. Power analyses were performed to explore sample size as a function of treatment effect. RESULTS: Cognitively unimpaired Aß+ participants approach mild cognitive impairment (MCI) levels of performance 6 years after baseline, on average. Achieving 80% power in a simulated 4-year treatment trial, assuming a 25% treatment effect, required 2,000 participants/group. Multiple factors interacted with Aß to predict cognitive decline; however, these findings were all cohort-specific. Despite design differences across the cohorts, with large sample sizes and sufficient follow-up time, the Aß+ groups declined consistently on cognitive composite measures. CONCLUSIONS: A preclinical AD population declines to the cognitive performance of an early MCI population in 6 years. Slowing this rate of decline by 40%-50% delays clinically relevant impairment by 3 years-a potentially meaningful treatment effect. However, assuming a 40%-50% drug effect highlights the difficulties in preclinical AD trial design, as a more commonly assumed treatment effect of 25% results in a required sample size of 2,000/group. Designers of preclinical AD treatment trials need to prepare for larger and longer trials than are currently being considered. Interactions with Aß status were inconsistent and not readily generalizable.


Assuntos
Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Compostos de Anilina , Doenças Assintomáticas , Benzotiazóis , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Meios de Contraste , Progressão da Doença , Etilenoglicóis , Feminino , Humanos , Masculino , Rememoração Mental , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Tiazóis , Fatores de Tempo , Teste de Sequência Alfanumérica
19.
Acta Neurol Scand ; 140(4): 281-289, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31265131

RESUMO

OBJECTIVES: To study the development of cognitive and emotional symptoms between 3 and 12 months after a minor stroke. MATERIAL AND METHODS: We included patients from stroke units at hospitals in the Central Norway Health Authority and from Haukeland University Hospital. We administered a selection of cognitive tests, and the patients completed a questionnaire 3 and 12 months post-stroke. Cognitive impairment was defined as impairment of ≥2 cognitive tests. RESULTS: A total of 324 patients completed the 3-month testing, whereas 37 patients were lost to follow-up at 12 months. The results showed significant improvement of cognitive function defined as impairment of ≥2 cognitive tests (P = .03) from months 3 to 12. However, most patients still showed cognitive impairment at 12 months with a prevalence of 35.4%. There is significant association between several of the cognitive tests and hypertension and smoking (P = .002 and .05). The prevalence of depression, but not anxiety, increased from 3 to 12 months (P = .04). The prevalence of fatigue did not change and was thus still high with 29.5% after 12 months. CONCLUSIONS: This study shows that an improvement of cognitive function still occurs between 3 and 12 months. Despite this, the prevalence of mostly minor cognitive impairment still remains high 12 months after the stroke. The increasing prevalence of depressive symptoms highlights the importance of being vigilant of depressive symptoms throughout the rehabilitation period. Furthermore, high prevalence of fatigue persisted.


Assuntos
Ansiedade/epidemiologia , Disfunção Cognitiva/epidemiologia , Depressão/epidemiologia , Fadiga/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Adulto , Idoso , Ansiedade/diagnóstico por imagem , Ansiedade/psicologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Estudos de Coortes , Depressão/diagnóstico por imagem , Depressão/psicologia , Fadiga/diagnóstico por imagem , Fadiga/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/psicologia
20.
Nat Commun ; 10(1): 2353, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164641

RESUMO

The link between brain amyloid-ß (Aß), metabolism, and dementia symptoms remains a pressing question in Alzheimer's disease. Here, using positron emission tomography ([18F]florbetapir tracer for Aß and [18F]FDG tracer for glucose metabolism) with a novel analytical framework, we found that Aß aggregation within the brain's default mode network leads to regional hypometabolism in distant but functionally connected brain regions. Moreover, we found that an interaction between this hypometabolism with overlapping Aß aggregation is associated with subsequent cognitive decline. These results were also observed in transgenic Aß rats that do not form neurofibrillary tangles, which support these findings as an independent mechanism of cognitive deterioration. These results suggest a model in which distant Aß induces regional metabolic vulnerability, whereas the interaction between local Aß with a vulnerable environment drives the clinical progression of dementia.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Disfunção Cognitiva/metabolismo , Emaranhados Neurofibrilares/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Compostos de Anilina , Animais , Animais Geneticamente Modificados , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Etilenoglicóis , Fluordesoxiglucose F18 , Humanos , Imagem por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Ratos
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