Latência e amplitude do P300 auditivo na doença de Alzheimer: uma revisão sistemática

O P300 desempenha um papel fundamental como método de avaliação e monitoramento das demências, entre elas a doença de Alzheimer. OBJETIVO: Realizar uma busca por artigos que analisaram os valores de latência e amplitude de P300 na doença de Alzheimer. MÉTODOS: Foi realizada uma busca nas seguintes bases de dados: Web of Science, PubMed/Medline, Psyc Info, Biological Abstracts e Scielo. Utilizaram-se as seguintes palavras-chave: speed of information processing, speed of processing, information processing, aged, older, elderly, older people, alzheimer dementia, alzheimer disease, Alzheimer, além de referências cruzadas dos artigos selecionados. RESULTADOS: Foram encontrados oito estudos que preencheram os critérios de inclusão adotados para o presente trabalho. Estes estudos mostraram que existe um consenso em relação ao aumento da latência de P300 de idosos com doença de Alzheimer quando comparados com idosos sem a doença. Porém, verifica-se que, com relação à amplitude de P300, ainda não há um consenso, mas, isso pode estar relacionado às diferentes variáveis metodológicas adotadas nos estudos revisados. CONCLUSÃO: Há necessidade de se padronizar as variáveis envolvidas no método de avaliação do P300 para idosos com doença de Alzheimer, para que seja possível comparar os valores de latência e amplitude de P300 dessa população.

Non-pharmacological interventions on cognitive functions in older people with mild cognitive impairment (MCI)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Gait and risk of falls associated with frontal cognitive functions at different stages of Alzheimer's disease

The decline in frontal cognitive functions contributes to alterations of gait and increases the risk of falls in patients with dementia, a category which included Alzheimer's disease (AD). The objective of the present study was to compare the gait parameters and the risk of falls among patients at different stages of AD, and to relate these variables with cognitive functions. This is a cross-sectional study with 23 patients with mild and moderate AD. The Clinical Dementia Rating was used to classify the dementia severity. The kinematic parameters of gait (cadence, stride length, and stride speed) were analyzed under two conditions: (a) single task (free gait) and (b) dual task (walking and counting down). The risk of falls was evaluated using the Timed Up-and-Go test. The frontal cognitive functions were evaluated using the Frontal Assessment Battery (FAB), the Clock Drawing Test (CDT) and the Symbol Search Subtest. The patients who were at the moderate stage suffered reduced performance in their stride length and stride speed in the single task and had made more counting errors in the dual task and still had a higher fall risk. Both the mild and the moderate patients exhibited significant decreases in stride length, stride speed and cadence in the dual task. Was detected a significant correlation between CDT, FAB, and stride speed in the dual task condition. We also found a significant correlation between subtest Similarities, FAB and cadence in the dual task condition. The dual task produced changes in the kinematic parameters of gait for the mild and moderate AD patients and the gait alterations are related to frontal cognitive functions, particularly executive functions.

Serum homocysteine and physical exercise in patients with Parkinson's disease

Background: Hyperhomocysteinemia is a major risk factor for cerebral and peripheral vascular diseases, as well as cortical and hippocampal injury, including an increased risk of dementia and cognitive impairment. Elevated serum homocysteine (Hcy) concentrations are common in patients with Parkinson's disease (PD) who have been treated with levodopa; however, physical exercises can help reduce Hcy concentrations. The aim of the present study was to compare serum Hcy levels in patients with PD who partook in regular physical exercises, sedentary PD patients, and healthy controls.Methods: Sixty individuals were enrolled in the present study across three groups: (i) 17 patients who did not partake of any type of exercise; (ii) 24 PD patients who exercised regularly; and (iii) 19 healthy individuals who did not exercise regularly. All participants were evaluated by Hoehn and Yahr scale, the Unified Parkinson's Disease Rating Scale (UPDRS) and Schwab and England scale (measure daily functionality). The serum levels of Hcy were analyzed by blood samples collected of each participant. An analysis of variance and a Tukey's post hoc test were applied to compare and to verify differences between groups. Pearson's correlation and stepwise multiple regression analyses were used to consider the association between several variables.Results: Mean plasma Hcy concentrations in individuals who exercised regularly were similar to those in the healthy controls and significantly lower than those in the group that did not exercise at all (P = 0.000). In addition, patients who did not exercise were receiving significantly higher doses of levodopa than those patients who exercised regularly (P = 0.001). A positive relationship between levodopa dose and Hcy concentrations (R(2) = 0.27; P = 0.03) was observed in patients who did not exercise, but not in those patients who exercised regularly (R(2) = 0.023; P = 0.15).Conclusions: The results of the present study suggest that, even with regular levodopa therapy, Hcy concentrations in PD patients who exercise regularly are significantly lower than in patients who do not exercise and are similar Hcy concentrations in healthy controls.

Imaginário e envelhecimento: imagens simbólicas de três nonagenários

Ensaio de hermenêutica sobre as imagens simbólicas de nonagenários com a finalidade de investigar as estruturas do imaginário prevalentes e suas organizações psíquicas. Por meio de entrevistas semanais abertas, foram coligidas estórias, grafismos, sonhos, devaneios e lembranças dos anciões. O material foi analisado analisado segundo a teoria do imaginário de Gilbert Durand, que propõe uma interpretação não pulsional do símbolo. Os critérios de amostragem foram: faixa etária acima de 90 anos, ausência de um quadro de demência senil arteriosclerótica (serem clinicamente saudáveis), atividade social e participação voluntária. Os resultados indicam ausência de uma estrutura do imaginário recorrente, presença de uma exuberante imaginação simbólica, permeabilidade entre conteúdos da memória e imaginação, além de criatividade e vívidos processos afetivos.

Investigações epidemiológicas sobre demência nos países em desenvolvimento

Na medida em que a população mundial está envelhecendo, a demência está se constituindo em importante problema de saúde pública, particularmente nos países em desenvolvimento. Investigações epidemiológicas nestes países são escassas e apresentam dificuldades metodológicas adicionais, principalmente no que se refere à adequação sociocultural dos instrumentos utilizados para a definição de casos. Tendo em vista estas preocupações, foi fundado o Grupo de Pesquisa em Demência 10/66, que é constituído por uma rede internacional de pesquisadores, predominantemente de países em desenvolvimento. O nome do grupo tem como referência o paradoxo de que menos de 10% dos estudos populacionais sobre demência são dirigidos aos 2/3 ou mais de casos de pessoas com demência que vivem em países em desenvolvimento. O objetivo do artigo é atualizar informações da literatura sobre as diferenças de prevalência e incidência de demência encontradas em países desenvolvidos e em desenvolvimento.

DIAGNOSIS of REGIONAL CEREBRAL BLOOD FLOW ABNORMALITIES USING SPECT: AGREEMENT BETWEEN INDIVIDUALIZED STATISTICAL PARAMETRIC MAPS and VISUAL INSPECTION BY NUCLEAR MEDICINE PHYSICIANS WITH DIFFERENT LEVELS of EXPERTISE IN NUCLEAR NEUROLOGY

INTRODUCTION: Visual analysis is widely used to interpret regional cerebral blood flow (rCBF) SPECT images in clinical practice despite its limitations. Automated methods are employed to investigate between-group rCBF differences in research Studies but have rarely been explored in individual analyses.OBJECTIVES: To compare visual inspection by nuclear physicians with the automated statistical parametric mapping program using a SPECT dataset of patients with neurological disorders and normal control images.METHODS: Using statistical parametric mapping, 14 SPECT images from patients with various neurological disorders were compared individually with a databank of 32 normal images using a statistical threshold of p<0.05 (corrected for multiple comparisons at the level of individual voxels or clusters). Statistical parametric mapping results were compared with Visual analyses by a nuclear physician highly experienced in neurology (A) as well as a nuclear physician with a general background of experience (B) who independently classified images as normal or altered, and determined the location of changes and the severity.RESULTS: of the 32 images of the normal databank, 4 generated maps showing rCBF abnormalities (p<0.05, corrected). Among the 14 images from patients with neurological disorders, 13 showed rCBF alterations. Statistical parametric mapping and physician A completely agreed on 84.37% and 64.28% of cases from the normal databank and neurological disorders, respectively. The agreement between statistical parametric mapping and ratings of physician B were lower (71.18% and 35.71%, respectively).CONCLUSION: Statistical parametric mapping replicated the findings described by the more experienced nuclear physician. This finding suggests that automated methods for individually analyzing rCBF SPECT images may be a valuable resource to complement visual inspection in clinical practice.

Depression severity levels and cognitive functions in institutionalized elderly patients

Depression is a highly prevalent illness among institutionalized aged and assumes peculiar characteristics such as the risk for progressing to dementia. The aims of this study was to assess the cognitive functions of institutionalized elderly with clinical diagnosis of depression and compare the severity of depressive symptoms with cognitive performance. From 120 residents at a nursing home in Rio Claro, Brazil, we study 23 individuals (mean age: 74.3 years; mean schooling: 4.0 years) with diagnosis of depression. At first, a clinical diagnosis of depression and measurement of its symptoms using the Geriatric Depression Scale were performed. The patient then underwent a neuropsychological assessment based on the following tests: Mini-Mental Examination, Verbal Fluency, Visual Perception, Immediate Memory, Recent Memory, Recognition, Clock Drawing Test. The patients were divided into two groups: those with less severe depression symptoms (Group 1: N=9) and more severe symptoms (Group 2: N=14). The significant difference between symptom severity of the two groups was p=0.0001. Patients with more severe symptoms revealed a slightly inferior cognitive performance in most of the tests when compared to those with less severe symptoms (p>0.05). In relation to Verbal Fluency, patients with more severe depression symptoms presented a significantly inferior cognitive performance when compared to those with less severe symptoms (p=0.0082). Verbal Fluency revealed to be a more sensitive test for measuring early cognitive alterations in institutionalized aged with depression, and appears to be a useful resource in monitoring the cognitive functions of patients faced with the risk of dementia. © Copyright Moreira Jr. Editora.

Caracterização e análise do estado mental e funcional de idosos institucionalizados em instituições públicas de longa permanência

Background: This study had as objective to characterize the institutionalized elderly residents in three long-term care facilities, about their functional capacity and mental state, and to evaluate if there is a correlation between both. Methods: To do so, three instruments were used: an identification form, the Mini-Mental State Examination (MMSE) and Barthel's Index. For statistical analysis the Person's Correlation and ANOVA Test were used. Results: The population studied consisted of 115 elders with ages between 62 and 104 years old, 40.66% females and 59.13% males. 49.56% are literate and 50.43% illiterate. Regarding the marital status, singles (46.65%) and widows (21.8%) were predominant. About the mental and functional state, there was a high rate of elders showing cognitive decline (76.72%) and functionally independent (75.65%). Conclusions: According to the results, one can notice that there is a mild degree of correlation between the Barthel's Index and MMSE (r = 0.441; p < 0.000), and the variables of gender and age are not influenced in the results of these instruments. There is a significant statistical relation (p < 0.0001) between education and mental and/or functional state of the individual.

El tratamiento fisioterapéutico ¿es efectivo en el mantenimiento físico y en la reducción del declive cognitivo de las demencias?

Introduction. Dementia is a chronic and neurodegenerative disease responsible for a progressive decline of cognition and physical capacity. Objective: To verify the effectiviness of three months of physiotherapy intervention on cognitive functions and balance of institutionilized elderly people with dementia. Patients and methods. This study has comprised thirty subjects, divided in two groups: EG (experimental group) and CG (control group). EG was composed by 15 participants with mean age of 71,6 ± 8,5 years and scholarity of 4,7 ± 4,2 years. CG was formed by 15 subjects with mean age of 78,5 ± 7,6 years and scholarity of 2,2 ± 1,8 years. The sample was evaluated by means of the following instruments: Mini-Mental State Examination, Semantic Verbal Fluency test, Clock Drawing test, Berg Balance Scale and Timed Get Up and Go test. The statistical procedures were done by means of Multivariate Analisis of Variance (MANOVA), with significance of 5 % (p < 0,05). Results. The results has shown a heterogeneity of both groups related to age (F = 0,2, p < 0,05) and scholarity (F = 2,6, p < 0,05). MANOVA pointed beneficts of physiotherapy on balance (F = 7,3, p < 0,01) but not on cognitive functions (F = 0,3, p > 0,05). Conclusions. Three months of physiotherapy were effective to improuve physical capacity of institucionilized elderly people with dementia. Neverthless, it was not able to minimize cognitive decline commonly seen on dementia. The question if a prolonged intervention could propitiate cognitive beneficts remains, specially in a more homogeneous groups.

Influencia de la actividad física en la enfermedad de Alzheimer: un caso clínico

Alzheimer's dementia (AD) is a neurodegenerative disorder that causes motor and cognitive decline. The aim of this study was to analyze the influence of a specific physical activity program on the cognitive, depressive symptoms and functional capacity of patients with diagnosis of probable AD. The subject, a 79-year old woman, participated in this program for three months, with 50 min sessions three times a week. The instruments used were the Cambridge Cognitive Examination; the Geriatric Depression Scale; and the Battery of the American Alliance for Health Physical Education, Recreation and Dance. The results in relationship with the depressive symptoms and functional capacity were significantly positive. There were no changes in regards to the patient's cognitive functions. In conclusion, this physical activity program seems to be an important part of the treatment for patients with AD, as it improves the functional capacity and also stimulates cognitive tasks. © 2008 Asociación Española de Fisioterapeutas.

Atitudes distintas de profssionais de diferentes especialidades médicas relacionadas à autonomia e aspectos jurídicos no cuidado de pacientes com demência

The evaluation of competence of Alzheimer's disease (AD) patients to assume personal or collective responsibilities and the resulting legal implications is a relevant issue. Objectives: The aim of this study was to evaluate the attitudes of different medical specialists towards the disability of patients with Alzheimer's disease and practitioners' competence to interfere with decision-making autonomy. Methods: Professionals from different areas (Neurology, Psychiatry, Geriatrics, and General Practice) were interviewed by one of the authors, after being presented a fictitious clinical case which raised several topics, namely: [1] Critical judgment and capacity of the patient to take decisions related to daily activities; [2] The role of family physicians in nominating trustees and caregivers. Results: Answers to the first question did not differ regarding degree of preservation of awareness but at least 25% stressed that the patient must be carefully listened to, independent of caregiver or legal representative opinion. There were significant knowledge gaps in responses to the second question. Half of the physicians interviewed did not have adequate information about the legal aspects of caring for patients with Alzheimer's disease. Conclusions: Legal aspects is a topic that must be incorporated into professional training in order to improve attitudes toward the long-term management of patients with dementia.

Apatia na doença de alzheimer: Contribuição para uma visão clínica da progressão da demência

In addition to cognitive impairment, apathy is increasingly recognized as an important neuropsychiatric syndrome in Alzheimer's disease (AD). Aims: To identify the relationship between dementia severity and apathy levels, and to discuss the association of this condition with other psychopathological manifestations in AD patients. Methods: This study involved 15 AD patients (mean age: 77 years; schooling: 4.9 years), with mild, moderate and severe dementia, living in Rio Claro S P, Brazil. Procedures included evaluation of cognitive status by the Mini-Mental State Examination, Clinical Dementia Rating, and Global Deterioration Scale. Apathy syndrome was assessed by the Apathy Evaluation Scale and Neuropsychiatric Inventory (NPI-apathy domain). Other psychopathological manifestations such as depression were also considered. Results: Patients with more severe dementia presented higher levels of apathy, reinforcing the hypothesis that apathy severity aggravates as the disease progresses. Using the Spearman coefficient correlation an association was identified between the MMSE and Apathy Evaluation Scale (r=0.63; p=0.01), and also between the MMSE and NPI-apathy domain (r=0.81; p=0.01). Associations were also found between the Global Deterioration Scale and Apathy Evaluation Scale (r=0.58; p=0.02), and between the Global Deterioration Scale and NPI-apathy domain (r=0.81; p=0.01). Conclusions: Apathy is a distinct syndrome among patients with AD and increases with global deterioration.

Estudo longitudinal de rastreio cognitivo em sujeitos da comunidade

Cognitive changes in normal aging can be similar to the alterations that take place in the initial stages of a dementia process. Longitudinal studies can provide a better understanding of this progression. Objectives: To evaluate the cognitive and functional evolution of community-dwelling individuals without dementia through a three-year longitudinal study. Methods: 168 individuals were evaluated in 2006. Three years later in 2009, 73 of these subjects were reevaluated as regards cognition and functionality using the Mini Mental State Examination (MMSE), Brief Cognitive Battery (BCB) and the Pfeffer Functional Activities Questionnaire. The statistical analysis included descriptive measurements, the Wilcoxon's test for intra-group comparison, and the Spearman's correlation coefficient test for comparing cognitive and functionality scores. Results: After three years, the Wilcoxon's test showed a discreet yet significant cognitive decline (MMSE: -0.7 points; p=0.02; Z= -2.29; and global score on the BCB: +3.6 points; p=0.02; Z= -2.29), in addition to functional decline (Pfeffer: +0.7 points; p= 0.001; Z= -3.38). Conclusions: After three years of follow-up we observed a discreet yet significant functional and cognitive decline in the subjects. Longitudinal cognitive screening represents an important strategy in the early identification of changes from normal conditions to a dementia process.