Renato Anghinah

Diagnóstico de doença de Alzheimer no Brasil: avaliação cognitiva e funcional. Recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

The educational and cultural heterogeneity of the Brazilian population leads to peculiar characteristics regarding the diagnosis of Alzheimers disease (AD). This consensus had the objective of recommending evidence-based guidelines for the clinical diagnosis of AD in Brazil. Studies on the diagnosis of AD published in Brazil were systematically evaluated in a thorough research of PUBMED and LILACS databases. For global cognitive evaluation, the Mini-Mental State Examination was recommended; for memory evaluation: delayed recall subtest of CERAD or of objects presented as drawings; attention: trail-making or digit-span; language: Boston naming, naming test from ADAS-Cog or NEUROPSI; executive functions: verbal fluency or clock-drawing; conceptualization and abstraction: similarities from CAMDEX or NEUROPSI; construction: drawings from CERAD. For functional evaluation, IQCODE, or Pfeffer Questionnaire or Bayer Scale for Activities of Daily Living was recommended. The panel concluded that the combined use of cognitive and functional evaluation based on interview with informant is recommended.The educational and cultural heterogeneity of the Brazilian population leads to peculiar characteristics regarding the diagnosis of Alzheimers disease (AD). This consensus had the objective of recommending evidence-based guidelines for the clinical diagnosis of AD in Brazil. Studies on the diagnosis of AD published in Brazil were systematically evaluated in a thorough research of PUBMED and LILACS databases. For global cognitive evaluation, the Mini-Mental State Examination was recommended; for memory evaluation: delayed recall subtest of CERAD or of objects presented as drawings; attention: trail-making or digit-span; language: Boston naming, naming test from ADAS-Cog or NEUROPSI; executive functions: verbal fluency or clock-drawing; conceptualization and abstraction: similarities from CAMDEX or NEUROPSI; construction: drawings from CERAD. For functional evaluation, IQCODE, or Pfeffer Questionnaire or Bayer Scale for Activities of Daily Living was recommended. The panel concluded that the combined use of cognitive and functional evaluation based on interview with informant is recommended.

Diagnóstico de doença de Alzheimer no Brasil: critérios diagnósticos e exames complementares. Recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

This panel had the objective of recommending evidence-based guidelines for the clinical diagnosis of Alzheimers disease (AD) in Brazil. Guidelines from other countries and papers on the diagnosis of AD in Brazil were systematically evaluated in a thorough research of PUBMED and LILACS databases. The panel concluded that dementia diagnosis should be based on the DSM criteria and AD diagnosis, on the McKhann et al. criteria (NINCDS-ADRDA). The recommended auxiliary tests are: blood cell count, blood urea nitrogen, serum levels of creatinine, free-tyroxine, thyroid-stimulant hormone, albumin, hepatic enzymes, vitamin B12 and calcium, serological tests for syphilis and, for those aged less than 60 years, serological tests for HIV. Cerebrospinal fluid examination is recommended in special situations. Computed tomography (or preferentially magnetic resonance imaging, when available) is mandatory and has the main objective of excluding other diseases. SPECT and EEG are optional diagnostic methods.

Performance of a Brazilian population on the test of functional health literacy in adults

OBJECTIVE To analyze the scoring obtained by an instrument, which evaluates the ability to read and understand items in the health care setting, according to education and age. METHODS The short version of the Test of Functional Health Literacy in Adults was administered to 312 healthy participants of different ages and years of schooling. The study was conducted between 2006 and 2007, in the city of São Paulo, Southeastern Brazil. The test includes actual materials such as pill bottles and appointment slips and measures reading comprehension, assessing the ability to read and correctly pronounce a list of words and understand both prose passages and numerical information. Pearson partial correlations and a multiple regression model were used to verify the association between its scores and education and age. RESULTS The mean age of the sample was 47.3 years(sd=16.8) and the mean education was 9.7 years(sd=5; range: 1 - 17). A total of 32.4% of the sample showed literacy/numeracy deficits, scoring in the inadequate and marginal functional health literacy ranges. Among the elderly (65 years or older) this rate increased to 51.6%. There was a positive correlation between schooling and scores (r=0.74; p<0.01) and a negative correlation between age and the scores (r=-0.259; p<0.01). The correlation between the scores and age was not significant when the effects of education were held constant (rp=-0.031, p=0.584). A significant association (B=3.877, Beta =0.733; p<0.001) was found between schooling and scores. Age was not a significant predictor in this model (B=-0.035, Beta=-0.22; p=0.584). CONCLUSIONS The short version of the Test of Functional Health Literacy in Adults was a suitable tool to assess health literacy in the study population. The high number of individuals classified as functional illiterates in this test highlights the importance of special assistance to help them properly understand directions for healthcare.OBJETIVO: Analisar os escores de instrumento que avalia habilidade de leitura e compreensao de materiais da area da saude segundo escolaridade e idade. METODOS: Foram avaliados 312 participantes saudaveis de diferentes idades por meio da versao reduzida do instrumento Test of Functional Health Literacy in Adults. O estudo foi realizado entre 2006 e 2007 na cidade de Sao Paulo (SP). O instrumento envolve materiais como frascos de medicamentos e cartoes de agendamento de consultas, avaliando a compreensao de leitura e de conceitos numericos. Os testes de correlacao parcial e de Pearson e um modelo de regressao multipla foram usados para verificar a associacao entre os escores no instrumento, escolaridade e idade. RESULTADOS: As medias de idade e de escolaridade da amostra foram respectivamente 47,3 (dp=16,8 ) e 9,7 (dp=5; de um a 17 anos de estudo). O total de 32,4% da amostra mostraram deficits de alfabetizacao funcional/ uso de conceitos numericos na area de saude, com desempenho inadequado ou limitrofe no instrumento. Entre idosos (65 anos ou mais) esta taxa atingiu 51,6%. Encontrou-se correlacao positiva entre anos de estudo e escores no instrumento (r=0,740; p<0,01) e correlacao negativa entre idade e escores no instrumento (r=-0,259; p<0,01). A correlacao entre escores no instrumento e idade nao foi significante quando os efeitos da escolaridade foram controlados (r=-0,031, p=0,584). Uma associacao significante (B=3,877, Beta=0,733; p<0,001) foi encontrada entre anos de estudo e escores no instrumento. A idade nao foi uma variavel preditiva no modelo (B=-0,035, Beta=-0,22; p=0,584). CONCLUSOES: O instrumento e adequado para avaliar a alfabetizacao funcional em saude na populacao brasileira. O elevado numero de individuos classificados como analfabetos funcionais indica a importância de adocao de medidas especiais para ajudar estes individuos a compreenderem corretamente as orientacoes para cuidados de saude.

Prevalence of potentially reversible dementias in a dementia outpatient clinic of a tertiary university-affiliated hospital in Brazil

The importance of investigating the etiology for dementia lies in the possibility of treating potentially reversible dementias. The aims of this retrospective study are to determine the prevalence of potentially reversible dementias among 454 outpatients seen at the Cognitive and Behavioral Neurology Unit, Hospital das Clínicas, São Paulo University School of Medicine-Brazil, between the years of 1991 and 2001, and observe their evolution in follow-up. Among the initial 454 patients, 275 fulfilled the DSM-IV criteria for dementia. Alzheimers disease was the most frequent diagnosis (164 cases; 59.6%). Twenty-two cases (8.0%) of potentially reversible dementia were observed, the most frequent diagnoses being neurosyphilis (nine cases) and hydrocephalus (six cases). Full recovery was observed in two patients and partial recovery in 10 patients. Two cases were not treated and eight cases were lost on follow-up. The prevalence found in the present study falls within the range reported in previous studies (0-30%).

Comparison between two tests of delayed recall for the diagnosis of dementia

UNLABELLED Diagnosis of dementia is a challenge in populations with heterogeneous educational background. OBJECTIVE To compare the accuracies of two delayed recall tests for the diagnosis of dementia in a community with high proportion of illiterates. METHOD The delayed recall of a word list from the CERAD battery (DR-CERAD) was compared with the delayed recall of objects presented as line drawings from the Brief Cognitive Screening Battery (DR-BCSB) using ROC curves. Illiterate (23 controls and 17 patients with dementia) and literate individuals (28 controls and 17 patients with dementia) were evaluated in a community-dwelling Brazilian population. RESULTS The DR-BCSB showed higher accuracy than the DR-CERAD in the illiterate (p=0.029), similar accuracy in the literate individuals (p=0.527), and a trend for higher accuracy in the entire population (p=0.084). CONCLUSION the DR-BCSB could be an alternative for the diagnosis of dementia in populations with high proportion of illiterates.

Improving Alzheimer's Disease Diagnosis with Machine Learning Techniques:

There is not a specific test to diagnose Alzheimers disease (AD). Its diagnosis should be based upon clinical history, neuropsychological and laboratory tests, neuroimaging and electroencephalography (EEG). Therefore, new approaches are necessary to enable earlier and more accurate diagnosis and to follow treatment results. In this study we used a Machine Learning (ML) technique, named Support Vector Machine (SVM), to search patterns in EEG epochs to differentiate AD patients from controls. As a result, we developed a quantitative EEG (qEEG) processing method for automatic differentiation of patients with AD from normal individuals, as a complement to the diagnosis of probable dementia. We studied EEGs from 19 normal subjects (14 females/5 males, mean age 71.6 years) and 16 probable mild to moderate symptoms AD patients (14 females/2 males, mean age 73.4 years. The results obtained from analysis of EEG epochs were accuracy 79.9% and sensitivity 83.2%. The analysis considering the diagnosis of each individual patient reached 87.0% accuracy and 91.7% sensitivity.

Characterizing Alzheimer’s Disease Severity via Resting-Awake EEG Amplitude Modulation Analysis

Changes in electroencephalography (EEG) amplitude modulations have recently been linked with early-stage Alzheimer’s disease (AD). Existing tools available to perform such analysis (e.g., detrended fluctuation analysis), however, provide limited gains in discriminability power over traditional spectral based EEG analysis. In this paper, we explore the use of an innovative EEG amplitude modulation analysis technique based on spectro-temporal signal processing. More specifically, full-band EEG signals are first decomposed into the five well-known frequency bands and the envelopes are then extracted via a Hilbert transform. Each of the five envelopes are further decomposed into four so-called modulation bands, which were chosen to coincide with the delta, theta, alpha and beta frequency bands. Experiments on a resting-awake EEG dataset collected from 76 participants (27 healthy controls, 27 diagnosed with mild-AD, and 22 with moderate-AD) showed significant differences in amplitude modulations between the three groups. Most notably, i) delta modulation of the beta frequency band disappeared with an increase in disease severity (from mild to moderate AD), ii) delta modulation of the theta band appeared with an increase in severity, and iii) delta modulation of the beta frequency band showed to be a reliable discriminant feature between healthy controls and mild-AD patients. Taken together, it is hoped that the developed tool can be used to assist clinicians not only with early detection of Alzheimer’s disease, but also to monitor its progression.

Time perception distortion in neuropsychiatric and neurological disorders.

There is no sense organ specifically dedicated to time perception, as there is for other senses such as hearing and vision. However, this subjective sense of time is fundamental to our conception of reality and it creates the temporal course of events in our lives. Here, we explored neurobiological relations from the clinical perspective, examining timing ability in patients with different neurological and psychiatric conditions (e.g. Parkinsons disease, depression, bipolar disorder, anxiety disorders and schizophrenia). The neural bases of present distortions in time perception and temporal information processing still remain poorly understood. We reviewed: a) how the brain is capable of encoding time in different environments and multiple tasks, b) different models of interval timing, c) brain structures and neurotransmitters associated with time perception, d) the relationship between memory and time perception, e) neural mechanisms underlying different theories in neural and mental processes, and f) the relationship between different mental diseases and time perception. Bibliographic research was conducted based on publications over the past thirteen years written in English in the databases Scielo, Pubmed/MEDLINE, ISI Web of Knowledge. The time perceptions research are executed to evaluate time perception in mental diseases and can provide evidence for future clinical applications.

The effects of automated artifact removal algorithms on electroencephalography-based Alzheimer's disease diagnosis

Over the last decade, electroencephalography (EEG) has emerged as a reliable tool for the diagnosis of cortical disorders such as Alzheimers disease (AD). EEG signals, however, are susceptible to several artifacts, such as ocular, muscular, movement, and environmental. To overcome this limitation, existing diagnostic systems commonly depend on experienced clinicians to manually select artifact-free epochs from the collected multi-channel EEG data. Manual selection, however, is a tedious and time-consuming process, rendering the diagnostic system “semi-automated.” Notwithstanding, a number of EEG artifact removal algorithms have been proposed in the literature. The (dis)advantages of using such algorithms in automated AD diagnostic systems, however, have not been documented; this paper aims to fill this gap. Here, we investigate the effects of three state-of-the-art automated artifact removal (AAR) algorithms (both alone and in combination with each other) on AD diagnostic systems based on four different classes of EEG features, namely, spectral, amplitude modulation rate of change, coherence, and phase. The three AAR algorithms tested are statistical artifact rejection (SAR), blind source separation based on second order blind identification and canonical correlation analysis (BSS-SOBI-CCA), and wavelet enhanced independent component analysis (wICA). Experimental results based on 20-channel resting-awake EEG data collected from 59 participants (20 patients with mild AD, 15 with moderate-to-severe AD, and 24 age-matched healthy controls) showed the wICA algorithm alone outperforming other enhancement algorithm combinations across three tasks: diagnosis (control vs. mild vs. moderate), early detection (control vs. mild), and disease progression (mild vs. moderate), thus opening the doors for fully-automated systems that can assist clinicians with early detection of AD, as well as disease severity progression assessment.

Estudo da coerência do eletrencefalograma para a banda de frequência alfa em indivíduos adultos normais e com provável demência do tipo Alzheimer

We studied the occiptal inter-hemispheric coherence (IHCoh) of EEG (electrodes O1-O2) for alpha band (alpha1 - 8,0 to 10,0 Hz and alpha2 - 10,1 to 12,5 Hz) in healthy adults and Alzheimers type dementia (ATD) subjects, to observe if there is any significant difference between these two groups that could help in the early diagnosis of ATD. We found a decrease of occipital IHCoh in ATD group for both alpha sub-bands. We believe that Coh analysis of EEG is a powerful auxiliary method in ATD diagnosis.