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1.
Phys Rev Lett ; 125(12): 128102, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016724

RESUMO

Neurodegenerative diseases, such as Alzheimer's or Parkinson's disease, show characteristic degradation of structural brain networks. This degradation eventually leads to changes in the network dynamics and degradation of cognitive functions. Here, we model the progression in terms of coupled physical processes: The accumulation of toxic proteins, given by a nonlinear reaction-diffusion transport process, yields an evolving brain connectome characterized by weighted edges on which a neuronal-mass model evolves. The progression of the brain functions can be tested by simulating the resting-state activity on the evolving brain network. We show that while the evolution of edge weights plays a minor role in the overall progression of the disease, dynamic biomarkers predict a transition over a period of 10 years associated with strong cognitive decline.


Assuntos
Demência/patologia , Modelos Neurológicos , Doenças Neurodegenerativas/patologia , Animais , Relógios Biológicos , Encéfalo/patologia , Encéfalo/fisiopatologia , Morte Celular/fisiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Conectoma/métodos , Demência/fisiopatologia , Humanos , Camundongos , Doenças Neurodegenerativas/fisiopatologia , Neurônios/patologia
3.
PLoS Comput Biol ; 16(9): e1008186, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32941425

RESUMO

Identifying heterogeneous cognitive impairment markers at an early stage is vital for Alzheimer's disease diagnosis. However, due to complex and uncertain brain connectivity features in the cognitive domains, it remains challenging to quantify functional brain connectomic changes during non-pharmacological interventions for amnestic mild cognitive impairment (aMCI) patients. We present a quantitative method for functional brain network analysis of fMRI data based on the multi-graph unsupervised Gaussian embedding method (MG2G). This neural network-based model can effectively learn low-dimensional Gaussian distributions from the original high-dimensional sparse functional brain networks, quantify uncertainties in link prediction, and discover the intrinsic dimensionality of brain networks. Using the Wasserstein distance to measure probabilistic changes, we discovered that brain regions in the default mode network and somatosensory/somatomotor hand, fronto-parietal task control, memory retrieval, and visual and dorsal attention systems had relatively large variations during non-pharmacological training, which might provide distinct biomarkers for fine-grained monitoring of aMCI cognitive alteration. An important finding of our study is the ability of the new method to capture subtle changes for individual patients before and after short-term intervention. More broadly, the MG2G method can be used in studying multiple brain disorders and injuries, e.g., in Parkinson's disease or traumatic brain injury (TBI), and hence it will be useful to the wider neuroscience community.


Assuntos
Encéfalo , Disfunção Cognitiva , Diagnóstico por Computador/métodos , Distribuição Normal , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/terapia , Conectoma , Humanos , Imagem por Ressonância Magnética , Memória/fisiologia , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Aprendizado de Máquina não Supervisionado
4.
N Z Med J ; 133(1522): 112-127, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32994621

RESUMO

Dementia is recognised to be one of the most challenging diseases facing society, both now and in the future, with its prevalence estimated to increase substantially by 2050. The potential contributions of age-related sensory deficits have attracted little attention until recently, when a landmark study suggested that hearing loss could be a greater risk factor for dementia than hypertension, obesity, smoking, depression, physical inactivity or social isolation. Over the last decade, evidence has been gradually accumulating to suggest that the other part of the inner ear, the balance organs or 'vestibular system', might also be important in the development of cognitive dysfunction and dementia. Increasing evidence suggests that dizziness associated with vestibular dysfunction, a common reason for patients consulting their GPs, increases the risk of cognitive dysfunction, including dementia, and our understanding of the basic neurobiology of this sensory system supports this view. This paper aims to review and critically evaluate the relevant evidence.


Assuntos
Disfunção Cognitiva , Demência , Tontura , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/complicações , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/fisiopatologia , Demência/complicações , Demência/epidemiologia , Demência/fisiopatologia , Tontura/complicações , Tontura/epidemiologia , Tontura/fisiopatologia , Perda Auditiva , Humanos , Fatores de Risco , Doenças Vestibulares
5.
Am J Alzheimers Dis Other Demen ; 35: 1533317520960875, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32969235

RESUMO

We present a case report to showcase that behavioral, cognitive, and functional decline may be associated with COVID-19 stay-home guidance among older adults with pre-existent cognitive impairment. In a functionally independent and physically active older adult with Mild Cognitive Impairment, there was worsening in depression and anxiety symptoms associated with the restrictions of COVID-19. Functional decline was also noted as assessed by Instrumental Activities of Daily Living. We discuss solutions to mitigate the effects of COVID-19 restrictions in this vulnerable population.


Assuntos
Atividades Cotidianas , Ansiedade/psicologia , Disfunção Cognitiva/psicologia , Infecções por Coronavirus , Depressão/psicologia , Transtorno Depressivo/psicologia , Pandemias , Pneumonia Viral , Isolamento Social/psicologia , Idoso , Antidepressivos/uso terapêutico , Betacoronavirus , Disfunção Cognitiva/fisiopatologia , Transtorno Depressivo/tratamento farmacológico , Exercício Físico , Humanos , Vida Independente , Corrida Moderada , Solidão , Masculino , Mirtazapina/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Telemedicina , Trazodona/uso terapêutico
6.
PLoS One ; 15(7): e0236654, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735628

RESUMO

BACKGROUND: The ability to detect one's own memory capacity and develop strategies based on daily contexts is important for daily activities. The Contextual Memory Test (CMT) assesses self-awareness, self-efficacy, self-perception/evaluation of performance, recall, and strategy use that are associated with daily contexts, and could be a potentially suitable measurement for assessing memory and meta-memory in older adults with and without cognitive impairment. Nevertheless, the test-retest reliability and minimal detectable change (MDC) remain unknown in these individuals. OBJECTIVE: The purpose of this study was to examine test-retest reliability and calculate MDC of the CMT in healthy older adults and those with mild cognitive impairment (MCI). METHODS: Eighty-three participants completed the CMT twice with a one-month interval. Test-retest reliability was examined using intraclass correlation coefficient (ICC) in all seven domains of the CMT and the recognition subtest. The standard error of measurement (SEM) and MDC were calculated. The Bland-Altman analysis was performed to evaluate the degree of agreement between measurements. RESULTS: The ICC of five domains (self-awareness, self-perception/evaluation of performance, immediate/delayed/total recall) and the recognition subtest were good to excellent (ICC = 0.63-0.94) in healthy and MCI participants and the MDC% were less than 30% The ICC of the other two domains (self-efficacy and total strategy use, TSS) were low (ICC = 0.07-0.59) and the MDC% exceeded 30%. The Bland-Altman analysis showed generally better performance in the 2nd than the 1st measurement in most CMT domains. CONCLUSIONS: Our results revealed sufficient test-retest reliability and acceptable MDC in most CMT domains in healthy and MCI participants. Only the self-efficacy and TSS domains demonstrated low ICC and large MDC. Possible practice effects were found between repeated measurements. Clinicians should be cautious when evaluating self-efficacy and strategy use using the CMT in older adults. Further improvements are needed for these two domains.


Assuntos
Disfunção Cognitiva/fisiopatologia , Testes de Memória e Aprendizagem , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
7.
Med Clin North Am ; 104(5): 909-917, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32773054

RESUMO

Advancing age is associated with increasing risk of activities important for independence, such as driving and living alone. Cognitive impairment is more common with older age; financial resources and social support may dwindle. Risk, cognitive impairment, and decisional capacity each change over time. Transparent decision making and harm reduction help balance risk and safety. When a patient lacks decisional capacity, an option that considers the patient's preferences and shows respect for the person is favored. Vulnerable patients making choices that are high risk, and patients for whom others are making such choices, may require state intervention.


Assuntos
Condução de Veículo , Disfunção Cognitiva , Vida Independente , Segurança , Populações Vulneráveis , Idoso , Condução de Veículo/legislação & jurisprudência , Condução de Veículo/psicologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Função Executiva , Humanos , Vida Independente/ética , Vida Independente/psicologia , Risco , Populações Vulneráveis/legislação & jurisprudência , Populações Vulneráveis/psicologia
8.
PLoS One ; 15(8): e0231294, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853207

RESUMO

Eigenvector alignment, introduced herein to investigate human brain functional networks, is adapted from methods developed to detect influential nodes and communities in networked systems. It is used to identify differences in the brain networks of subjects with Alzheimer's disease (AD), amnestic Mild Cognitive Impairment (aMCI) and healthy controls (HC). Well-established methods exist for analysing connectivity networks composed of brain regions, including the widespread use of centrality metrics such as eigenvector centrality. However, these metrics provide only limited information on the relationship between regions, with this understanding often sought by comparing the strength of pairwise functional connectivity. Our holistic approach, eigenvector alignment, considers the impact of all functional connectivity changes before assessing the strength of the functional relationship, i.e. alignment, between any two regions. This is achieved by comparing the placement of regions in a Euclidean space defined by the network's dominant eigenvectors. Eigenvector alignment recognises the strength of bilateral connectivity in cortical areas of healthy control subjects, but also reveals degradation of this commissural system in those with AD. Surprisingly little structural change is detected for key regions in the Default Mode Network, despite significant declines in the functional connectivity of these regions. In contrast, regions in the auditory cortex display significant alignment changes that begin in aMCI and are the most prominent structural changes for those with AD. Alignment differences between aMCI and AD subjects are detected, including notable changes to the hippocampal regions. These findings suggest eigenvector alignment can play a complementary role, alongside established network analytic approaches, to capture how the brain's functional networks develop and adapt when challenged by disease processes such as AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Mapeamento Encefálico/métodos , Disfunção Cognitiva/fisiopatologia , Idoso , Amnésia/fisiopatologia , Encéfalo/fisiopatologia , Córtex Cerebral/fisiopatologia , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Modelos Teóricos , Rede Nervosa/fisiopatologia , Vias Neurais/fisiopatologia
9.
BMC Neurol ; 20(1): 264, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611388

RESUMO

INTRODUCTION: The level of function of instrumental activities of daily living (IADL) is crucial for a person's autonomy. A clear understanding of the nature of IADL and its limitations in people with mild cognitive impairment (MCI) is lacking. Literature suggests numerous possible influencing factors, e.g. cognitive function, but has not considered other domains of human functioning, such as environmental factors. Our aim was to develop a comprehensive model of IADL functioning that depicts the relevant influencing factors. METHODS: We conducted a four-round online Delphi study with a sample of international IADL experts (N = 69). In the first round, panelists were asked to mention all possible relevant cognitive and physical function factors, as well as environmental and personal factors, that influence IADL functioning. In the subsequent rounds, panelists rated the relevance of these factors. Consensus was defined as: 1) ≥70% agreement between panelists on a factor, and 2) stability over two successive rounds. RESULTS: Response rates from the four rounds were high (83 to 100%). In the first round, 229 influencing factors were mentioned, whereof 13 factors reached consensus in the subsequent rounds. These consensual factors were used to build a model of IADL functioning. The final model included: five cognitive function factors (i.e. memory, attention, executive function, and two executive function subdomains -problem solving / reasoning and organization / planning); five physical function factors (i.e. seeing functions, hearing functions, balance, gait / mobility functions and functional mobility functions); two environmental factors (i.e. social network / environment and support of social network / environment); and one personal factor (i.e. education). CONCLUSIONS: This study proposes a comprehensive model of IADL functioning in people with MCI. The results from this Delphi study suggest that IADL functioning is not merely affected by cognitive function factors, but also by physical function factors, environmental factors and personal factors. The multiplicity of factors mentioned in the first round also underlines the individuality of IADL functioning in people with MCI. This model may serve as a basis for future research in IADL functioning in people with MCI.


Assuntos
Atividades Cotidianas , Cognição/fisiologia , Disfunção Cognitiva/fisiopatologia , Atividades Cotidianas/psicologia , Técnica Delfos , Função Executiva , Feminino , Humanos , Masculino , Memória , Testes Neuropsicológicos
10.
Neurology ; 95(10): e1333-e1340, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641520

RESUMO

OBJECTIVE: To assess cerebrovascular reactivity in response to a visual task in participants with cerebral amyloid angiopathy (CAA), Alzheimer disease (AD), and mild cognitive impairment (MCI) using fMRI. METHODS: This prospective cohort study included 40 patients with CAA, 22 with AD, 27 with MCI, and 25 healthy controls. Each participant underwent a visual fMRI task using a contrast-reversing checkerboard stimulus. Visual evoked potentials (VEPs) were used to compare visual cortex neuronal activity in 83 participants. General linear models using least-squares means, adjusted for multiple comparisons with the Tukey test, were used to estimate mean blood oxygen level-dependent (BOLD) signal change during the task and VEP differences between groups. RESULTS: After adjustment for age and hypertension, estimated mean BOLD response amplitude was as follows: CAA 1.88% (95% confidence interval [CI] 1.60%-2.15%), AD 2.26% (1.91%-2.61%), MCI 2.15% (1.84%-2.46%), and control 2.65% (2.29%-3.00%). Only patients with CAA differed from controls (p = 0.01). In the subset with VEPs, group was not associated with prolonged latencies or lower amplitudes. Lower BOLD amplitude response was associated with higher white matter hyperintensity (WMH) volumes in CAA (for each 0.1% lower BOLD response amplitude, the WMH volume was 9.2% higher, 95% CI 6.0%-12.4%) but not other groups (p = 0.002 for interaction) when controlling for age and hypertension. CONCLUSIONS: Mean visual BOLD response amplitude was lowest in participants with CAA compared to controls, without differences in VEP latencies and amplitudes. This suggests that the impaired visual BOLD response is due to reduced vascular reactivity in CAA. In contrast to participants with CAA, the visual BOLD response amplitude did not differ between those with AD or MCI and controls.


Assuntos
Doença de Alzheimer/fisiopatologia , Angiopatia Amiloide Cerebral/fisiopatologia , Circulação Cerebrovascular/fisiologia , Disfunção Cognitiva/fisiopatologia , Idoso , Estudos de Coortes , Estudos Transversais , Imagem Ecoplanar , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Córtex Visual/fisiopatologia
11.
Anesthesiology ; 133(3): 595-610, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32701572

RESUMO

BACKGROUND: Sevoflurane anesthesia induces Tau phosphorylation and cognitive impairment in neonatal but not in adult mice. This study tested the hypothesis that differences in brain Tau amounts and in the activity of mitochondria-adenosine triphosphate (ATP)-Nuak1-Tau cascade between the neonatal and adult mice contribute to the age-dependent effects of sevoflurane on cognitive function. METHODS: 6- and 60-day-old mice of both sexes received anesthesia with 3% sevoflurane for 2 h daily for 3 days. Biochemical methods were used to measure amounts of Tau, phosphorylated Tau, Nuak1, ATP concentrations, and mitochondrial metabolism in the cerebral cortex and hippocampus. The Morris water maze test was used to evaluate cognitive function in the neonatal and adult mice. RESULTS: Under baseline conditions and compared with 60-day-old mice, 6-day-old mice had higher amounts of Tau (2.6 ± 0.4 [arbitrary units, mean ± SD] vs. 1.3 ± 0.2; P < 0.001), Tau oligomer (0.3 ± 0.1 vs. 0.1 ± 0.1; P = 0.008), and Nuak1 (0.9 ± 0.3 vs. 0.3 ± 0.1; P = 0.025) but lesser amounts of ATP (0.8 ± 0.1 vs. 1.5 ± 0.1; P < 0.001) and mitochondrial metabolism (74.8 ± 14.1 [pmol/min] vs. 169.6 ± 15.3; P < 0.001) in the cerebral cortex. Compared with baseline conditions, sevoflurane anesthesia induced Tau phosphorylation at its serine 202/threonine 205 residues (1.1 ± 0.4 vs. 0.2 ± 0.1; P < 0.001) in the 6-day-old mice but not in the 60-day-old mice (0.05 ± 0.04 vs. 0.03 ± 0.01; P = 0.186). The sevoflurane-induced Tau phosphorylation and cognitive impairment in the neonatal mice were both attenuated by the inhibition of Nuak1 and the treatment of vitamin K2. CONCLUSIONS: Higher brain Tau concentrations and lower brain mitochondrial metabolism in neonatal compared with adult mice contribute to developmental stage-dependent cognitive dysfunction after sevoflurane anesthesia.


Assuntos
Anestésicos Inalatórios/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Disfunção Cognitiva/etiologia , Sevoflurano/farmacologia , Proteínas tau/farmacologia , Fatores Etários , Animais , Animais Recém-Nascidos , Disfunção Cognitiva/fisiopatologia , Modelos Animais de Doenças , Masculino , Camundongos
12.
Life Sci ; 258: 118107, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32682919

RESUMO

Cognitive impairment has been widely recognized as a common symptom of chronic stress. Ginsenoside Rd (GRd), the major active compound in Panax ginseng, was previously reported in various neurological researches. However, little research is available regarding on the effect of GRd on cognitive improvement in mice subjected to chronic stress. In the present study, we investigated the neuroprotective effects of GRd in chronic restraint stress (CRS)-induced cognitive deficits and explored the potential mechanism in male C57BL/6J mice. Our results demonstrated that oral administration of GRd for 28 days markedly increased the spontaneous alternation in Y-maze and the relative discrimination index in novel object or location recognition tests following CRS. Additionally, GRd treatment considerably increased the antioxidant enzymes activities in the hippocampus. The expression levels of hippocampus and serum inflammation factors in the CRS groups were also counter-regulated by GRd treatment. Meanwhile, GRd treatment could reverse CRS-induced the decrease in phosphorylated phosphoinositide 3-kinase (PI3K), camp-reflecting element binding protein (CREB), brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) expression in the hippocampus. These findings provided evidences that GRd improves cognitive impairment in CRS mice by mitigating oxidative stress and inflammation, while upregulating the hippocampal BDNF-mediated CREB signaling pathway.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ginsenosídeos/uso terapêutico , Restrição Física , Transdução de Sinais , Estresse Psicológico/tratamento farmacológico , Animais , Doença Crônica , Disfunção Cognitiva/sangue , Disfunção Cognitiva/fisiopatologia , Modelos Animais de Doenças , Ginsenosídeos/química , Ginsenosídeos/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/patologia , Hipocampo/fisiopatologia , Inflamação/sangue , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Atividade Motora/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Receptor trkB/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/sangue , Estresse Psicológico/fisiopatologia
13.
Science ; 369(6500): 167-173, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32646997

RESUMO

Reversing brain aging may be possible through systemic interventions such as exercise. We found that administration of circulating blood factors in plasma from exercised aged mice transferred the effects of exercise on adult neurogenesis and cognition to sedentary aged mice. Plasma concentrations of glycosylphosphatidylinositol (GPI)-specific phospholipase D1 (Gpld1), a GPI-degrading enzyme derived from liver, were found to increase after exercise and to correlate with improved cognitive function in aged mice, and concentrations of Gpld1 in blood were increased in active, healthy elderly humans. Increasing systemic concentrations of Gpld1 in aged mice ameliorated age-related regenerative and cognitive impairments by altering signaling cascades downstream of GPI-anchored substrate cleavage. We thus identify a liver-to-brain axis by which blood factors can transfer the benefits of exercise in old age.


Assuntos
Envelhecimento/sangue , Encéfalo/fisiologia , Cognição/fisiologia , Fígado/enzimologia , Neurogênese , Fosfolipase D/sangue , Condicionamento Físico Animal , Animais , Circulação Sanguínea , Encéfalo/irrigação sanguínea , Disfunção Cognitiva/sangue , Disfunção Cognitiva/fisiopatologia , Glicosilfosfatidilinositóis/metabolismo , Camundongos , Fosfolipase D/metabolismo , Regeneração , Transdução de Sinais
14.
PLoS One ; 15(7): e0234255, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726311

RESUMO

'Normal aging' in the brain refers to age-related changes that occur independent of disease, in particular Alzheimer's disease. A major barrier to mapping normal brain aging has been the difficulty in excluding the earliest preclinical stages of Alzheimer's disease. Here, before addressing this issue we first imaged a mouse model and learn that the best MRI measure of dendritic spine loss, a known pathophysiological driver of normal aging, is one that relies on the combined use of functional and structural MRI. In the primary study, we then deployed the combined functional-structural MRI measure to investigate over 100 cognitively-normal people from 20-72 years of age. Next, to cover the tail end of aging, in secondary analyses we investigated structural MRI acquired from cognitively-normal people, 60-84 years of age, who were Alzheimer's-free via biomarkers. Collectively, the results from the primary functional-structural study, and the secondary structural studies revealed that the dentate gyrus is a hippocampal region differentially affected by aging, and that the entorhinal cortex is a region most resistant to aging. Across the cortex, the primary functional-structural study revealed and that the inferior frontal gyrus is differentially affected by aging, however, the secondary structural studies implicated other frontal cortex regions. Together, the results clarify how normal aging may affect the brain and has possible mechanistic and therapeutic implications.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Senescência Celular/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Animais , Encéfalo/metabolismo , Mapeamento Encefálico/métodos , Disfunção Cognitiva/fisiopatologia , Espinhas Dendríticas/patologia , Giro Denteado/patologia , Córtex Entorrinal/patologia , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Camundongos , Pessoa de Meia-Idade
15.
Gerontology ; 66(4): 401-408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32623430

RESUMO

BACKGROUND: Many studies have demonstrated an inverse relationship between gait performance and cognitive impairment. The main purposes of this study were: (1) to design and validate a complex gait test (CGT) in older people, (2) to analyze the effects of age and sex on CGT, and (3) to analyze the association between CGT performance and physical functioning and cognitive measures. METHODS: A total of 279 older people (60-97 years) were analyzed in 2019. Fitness tests, gait performance, and several cognitive measures such asthe Trail-Walking Test and Montreal Cognitive Assessment were used. RESULTS: The CGT reported adequate reliability and validity parameters. In the test-retest analysis, the intra-class correlation coefficient was 0.868 (p < 0.001). There was a significant correlation between the CGT and Trail-Walking Test (r = 0.592; p < 0.001). The linear regression analysis showed that the CGT was associated with the Montreal Cognitive Assessment (R2 = 0.357; p =0.001). The binary logistic regression analysis revealed that a high CGT score was a risk factor for mild cognitive impairment (odds ratio 1.201, 95% CI 1.081-1.334; p = 0.001). The ROC curve of the mild cognitive impairment was predicted by the CGT performance (area under the curve = 0.768, 95% CI 0.647-0.889; p < 0.001), reaching the cut-off point at 20.25 s. CONCLUSIONS: The CGT showed good reliability and validity and may serve as a potential biomarker in mild cognitive impairment prediction in older adults aged 60-97 years.


Assuntos
Cognição/fisiologia , Teste de Esforço/normas , Marcha/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/fisiopatologia , Estudos de Coortes , Estudos Transversais , Feminino , Avaliação Geriátrica , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores Sexuais , Espanha , Caminhada/fisiologia
16.
Neurology ; 95(6): e662-e670, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32636325

RESUMO

OBJECTIVE: Early biomarkers for dementia with Lewy bodies (DLB) are lacking. To determine whether EEG differentiates the prodromal phase of DLB from other causes of mild cognitive impairment (MCI) and whether EEG is predictive for time to conversion from MCI to DLB, we compared EEGs and clinical follow-up of patients with MCI due to DLB with those of patients with MCI due to Alzheimer disease (MCI-AD). METHODS: We compared 37 patients with MCI who developed DLB during follow-up or had an abnormal 123I-PF-CIT SPECT scan (MCI-DLB) with 67 age-matched patients with MCI-AD. EEGs were assessed visually with a score of increasing abnormality (range 1-5). We performed fast Fourier transform to analyze the power spectrum. With survival analyses, EEG characteristics were related to time to progression to dementia. RESULTS: The visual EEG score was higher in MCI-DLB (score >2 in 60%) compared to MCI-AD (score >2 in 8%, p < 0.001). We found frontal intermittent delta activity in 22% of MCI-DLB, not in MCI-AD. Patients with MCI-DLB had a lower peak frequency (7.5 [6.0-9.9] Hz vs 8.8 [6.8-10.2] in MCI-AD, p < 0.001) and more slow-wave activity. Several individual EEG measures showed good performance to discriminate MCI-DLB from MCI-AD (areas under the curve up to 0.94). In MCI-DLB, high visual EEG score, diffuse abnormalities, and low α2 power were related to time to progression to dementia (hazard ratios 4.1, 9.9, 5.1, respectively). CONCLUSIONS: Profound EEG abnormalities are already present in the prodromal stage of DLB and have diagnostic and prognostic value. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that EEG abnormalities are more common in MCI-DLB than MCI-AD.


Assuntos
Eletroencefalografia , Doença por Corpos de Lewy/diagnóstico , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Diagnóstico Diferencial , Progressão da Doença , Diagnóstico Precoce , Feminino , Seguimentos , Análise de Fourier , Humanos , Radioisótopos do Iodo , Doença por Corpos de Lewy/líquido cefalorraquidiano , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/fisiopatologia , Masculino , Pessoa de Meia-Idade , Países Baixos , Fragmentos de Peptídeos/líquido cefalorraquidiano , Estudos Prospectivos , Compostos Radiofarmacêuticos , Avaliação de Sintomas , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Tropanos , Proteínas tau/líquido cefalorraquidiano
17.
BMJ ; 370: m2397, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699176

RESUMO

OBJECTIVE: To assess the effects of food supplementation on improving working memory and additional measures including cerebral blood flow in children at risk of undernutrition. DESIGN: Randomized controlled trial. SETTING: 10 villages in Guinea-Bissau. PARTICIPANTS: 1059 children aged 15 months to 7 years; children younger than 4 were the primary population. INTERVENTIONS: Supervised isocaloric servings (≈1300 kJ, five mornings each week, 23 weeks) of a new food supplement (NEWSUP, high in plant polyphenols and omega 3 fatty acids, within a wide variety and high fortification of micronutrients, and a high protein content), or a fortified blended food (FBF) used in nutrition programs, or a control meal (traditional rice breakfast). MAIN OUTCOME MEASUREMENTS: The primary outcome was working memory, a core executive function predicting long term academic achievement. Additional outcomes were hemoglobin concentration, growth, body composition, and index of cerebral blood flow (CBFi). In addition to an intention-to-treat analysis, a predefined per protocol analysis was conducted in children who consumed at least 75% of the supplement (820/925, 89%). The primary outcome was assessed by a multivariable Poisson model; other outcomes were assessed by multivariable linear mixed models. RESULTS: Among children younger than 4, randomization to NEWSUP increased working memory compared with the control meal (rate ratio 1.20, 95% confidence interval 1.02 to 1.41, P=0.03), with a larger effect in the per protocol population (1.25, 1.06 to 1.47, P=0.009). NEWSUP also increased hemoglobin concentration among children with anemia (adjusted mean difference 0.65 g/dL, 95% confidence interval 0.23 to 1.07, P=0.003) compared with the control meal, decreased body mass index z score gain (-0.23, -0.43 to -0.02, P=0.03), and increased lean tissue accretion (2.98 cm2, 0.04 to 5.92, P=0.046) with less fat (-5.82 cm2, -11.28 to -0.36, P=0.04) compared with FBF. Additionally, NEWSUP increased CBFi compared with the control meal and FBF in both age groups combined (1.14 mm2/s×10-8, 0.10 to 2.23, P=0.04 for both comparisons). Among children aged 4 and older, NEWSUP had no significant effect on working memory or anemia, but increased lean tissue compared with FBF (4.31 cm2, 0.34 to 8.28, P=0.03). CONCLUSIONS: Childhood undernutrition is associated with long term impairment in cognition. Contrary to current understanding, supplementary feeding for 23 weeks could improve executive function, brain health, and nutritional status in vulnerable young children living in low income countries. Further research is needed to optimize nutritional prescriptions for regenerative improvements in cognitive function, and to test effectiveness in other vulnerable groups. TRIAL REGISTRATION: ClinicalTrials.gov NCT03017209.


Assuntos
Anemia/dietoterapia , Disfunção Cognitiva/dietoterapia , Suplementos Nutricionais/efeitos adversos , Desnutrição/dietoterapia , Estado Nutricional/fisiologia , Sucesso Acadêmico , Anemia/epidemiologia , Estudos de Casos e Controles , Circulação Cerebrovascular/fisiologia , Criança , Pré-Escolar , Cognição/fisiologia , Disfunção Cognitiva/fisiopatologia , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Alimentos Fortificados/provisão & distribução , Guiné-Bissau/epidemiologia , Humanos , Lactente , Análise de Intenção de Tratamento/métodos , Masculino , Desnutrição/epidemiologia , Desnutrição/prevenção & controle , Micronutrientes/provisão & distribução , Medição de Risco
18.
Acta otorrinolaringol. esp ; 71(3): 175-280, mayo-jun. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-192633

RESUMO

OBJECTIVE: Presbycusis or age-related hearing loss is a bilaterally symmetric sensorineural hearing loss associated exclusively with age, excluding any other causes of hearing loss. Presbycusis is very relevant because of its high prevalence, and its consequences (e.g., alterations in communication, social isolation, depression, dementia), and the economic impact. This paper reports the first attempt to estimate the prevalence of presbycusis in an otologically normal population, i.e., without previous ear disease, exposure to noise, or potentially ototoxic substances, or familial hearing loss. METHODS: A total of 4290 subjects from 5 to 90 years old were included in the study. RESULTS: No statistically significant differences were found between right and left ear, nor between males and females, in any of the age groups. Presbycusis was detected over 60 years following the WHO classification; although the results vary depending on the classification used. Moderate hearing loss (≥ 41 dB) was detected in the population over 72 years. None of the subjects had severe or profound hearing impairment. The prevalence of presbycusis increased with age, being 100% in individuals aged 80 years and older. The prevalence of presbycusis is highly variable depending on the pure-tone averaged frequencies and the classification system used; therefore, a common classification system should be used. CONCLUSIONS: An otologically normal population is needed to establish the prevalence of presbycusis as in non-screened populations it is the hearing level including all types of hearing loss that is measured, but not presbycusis itself


ANTECEDENTES Y OBJETIVO: La presbiacusia o pérdida auditiva relacionada con la edad, es una hipoacusia neurosensorial bilateral y simétrica asociada exclusivamente a la edad. La presbiacusia es muy relevante debido a su alta prevalencia y sus consecuencias (alteraciones en la comunicación, aislamiento social, depresión, demencia) y el impacto económico. Este es el primer trabajo que aporta datos sobre la prevalencia de la presbiacusia en una población otológicamente normal, es decir, sin enfermedad auditiva previa, exposición a ruido o sustancias potencialmente ototóxicas o pérdida de audición familiar. MATERIAL Y MÉTODOS: Un total de 4.290 sujetos de 5 a 90 años de edad fueron incluidos en el estudio. RESULTADOS: No se encontraron diferencias entre el oído derecho y el izquierdo, ni entre varones y mujeres. La presbiacusia se detectó a partir de los 60 años siguiendo la clasificación de la OMS, aunque los resultados varían dependiendo de la clasificación utilizada. Se detectó hipoacusia moderada (≥ 41dB) en la población mayor de 72 años. Ninguno de los sujetos tenía hipoacusia grave o profunda. La prevalencia de presbiacusia aumentó con la edad, siendo del 100% en individuos de 80 años o más. La prevalencia de la presbiacusia es altamente variable dependiendo de las frecuencias promediadas y del sistema de clasificación utilizado; por lo tanto, debería utilizarse un sistema de clasificación común. CONCLUSIONES: Para establecer la prevalencia de la presbiacusia se necesita una población otológicamente normal ya que, si la población no está cribada, lo que se mide es la hipoacusia que incluye todos los tipos de pérdida auditiva, pero no la presbiacusia de forma aislada


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Presbiacusia/epidemiologia , Presbiacusia/classificação , Voluntários Saudáveis/estatística & dados numéricos , Audiometria , Análise de Variância , Disfunção Cognitiva/fisiopatologia
19.
Mayo Clin Proc ; 95(6): 1281-1292, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32498781

RESUMO

Dementia affects nearly 50 million people worldwide, translating into one new case every 3 seconds. Dementia syndrome is one of the leading causes of disability among older adults, yet it remains vastly underdiagnosed. A timely diagnosis of dementia is essential to ensuring optimal care and support of individuals and their loved ones. Although there is no single test for dementia, health care providers can use a structured approach to the workup and management of new cognitive symptoms. Comprehensive MEDLINE and PubMed searches were performed to develop an unbiased, practical diagnostic approach to these symptoms. This review guides primary care providers in the workup, diagnosis, delivery, and initial management of patients presenting with new cognitive symptoms.


Assuntos
Disfunção Cognitiva/diagnóstico , Demência/diagnóstico , Atenção Primária à Saúde/métodos , Idoso , Disfunção Cognitiva/fisiopatologia , Demência/fisiopatologia , Humanos , Programas de Rastreamento/métodos , Testes de Estado Mental e Demência
20.
World Neurosurg ; 138: 672-679, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32545020

RESUMO

OBJECTIVE: In this study, we considered the treatment of cognitive characteristics of Parkinson's subtypes under resting magnetic resonance imaging scans, and used magnetic resonance imaging to analyze brain activity characteristics of patients with Parkinson's subtypes at rest. METHODS: In this study, patients with neurological Parkinson's disease subtypes were selected: 27 patients in the tremor group, 33 patients in the orthostatic gastric instability group, and 3 patients with mild cognitive impairment and neuropathic Parkinson's disease. Scientific treatment was adopted. RESULTS: Nineteen patients had mild cognitive dysfunction tremor and unstable posture, and 23 of them had mild cognitive dysfunction. Fifteen healthy controls were subjected to resting state functional magnetic resonance imaging by plane echo imaging sequence scanning. Neurological diseases-Regional consistency analysis of brain regions in patients with Parkinson's disease increased, including the right lower lobe, while regional consistency analysis of brain regions decreased, including the right frontal gyrus, right middle anterior gyrus, and lateral cerebellum. CONCLUSIONS: The experimental results show that the local consistency analysis method based on resting magnetic resonance imaging scan can effectively detect the differences in early neural activity in patients with Parkinson's disease subtype cognitive impairment, and can effectively reflect the brain characteristics of Parkinson's disease.


Assuntos
Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Idoso , Estudos de Casos e Controles , Cognição , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Feminino , Neuroimagem Funcional , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Descanso , Tremor/fisiopatologia
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