ABSTRACT
OBJECTIVE: To compare the results of neuropsychological tests, evoked potentials N200 and P300 and polymorphisms of ApoE and BDNF rs6265 between patients with normal cognition and those with mild cognitive impairment (MCI) and Alzheimer's dementia (AD). METHODS: This is a cross-sectional study of elderly individuals with normal cognition and those with MCI and AD, who were submitted to evoked potential tests (N200 and P300) by means of hearing stimuli based on the auditory oddball paradigm. Genotyping was obtained by using the real-time PCR technique. RESULTS: Sixty-five patients were evaluated as follows: 14 controls, 34 with MCI and 17 with AD. N200 latency and P300 latency and amplitude were not associated with MCI and AD diagnosis. Patients with cognitive impairment (MCI or AD) showed increase in the latencies of P300 and N200. BNDF gene was not associated with cognitive impairment. CONCLUSION: Latencies of N200 and P300 increased in cognitively impaired patients with the presence of ApoE ε-4 allele.
Subject(s)
Alzheimer Disease/diagnosis , Apolipoproteins E/genetics , Brain-Derived Neurotrophic Factor/genetics , Cognitive Dysfunction/diagnosis , Evoked Potentials, Auditory/physiology , Aged , Aged, 80 and over , Alleles , Alzheimer Disease/etiology , Alzheimer Disease/physiopathology , Case-Control Studies , Cognitive Dysfunction/genetics , Cognitive Dysfunction/physiopathology , Cross-Sectional Studies , Female , Genotype , Humans , Male , Neuropsychological TestsABSTRACT
OBJECTIVE: Translate, transcultural adaptation and application to Brazilian Portuguese of the Alzheimer's Disease Cooperative Study - Activities of Daily Living (ADCS-ADL) scale as a cognitive screening instrument. METHOD: We applied the back translation added with pretest and bilingual methods. The sample was composed by 95 elderly individuals and their caregivers. Thirty-two (32) participants were diagnosed as mild cognitive impairment (MCI) patients, 33 as Alzheimer's disease (AD) patients and 30 were considered as cognitively normal individuals. RESULTS: There were only little changes on the scale. The Cronbach alpha coefficient was 0.89. The scores were 72.9 for control group, followed by MCI (65.1) and by AD (55.9), with a p-value < 0.001. The ROC curve value was 0.89. We considered a cut point of 72 and we observed a sensibility of 86.2%, specificity of 70%, positive predictive value of 86.2%, negative predictive value of 70%, positive likelihood ratio of 2.9 and negative likelihood ratio of 0.2. CONCLUSION: ADCS-ADL scale presents satisfactory psychometric properties to discriminate between MCI, AD and normal cognition.
Subject(s)
Cognition Disorders/diagnosis , Surveys and Questionnaires , Activities of Daily Living , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/physiopathology , Brazil , Case-Control Studies , Cognition Disorders/physiopathology , Cross-Cultural Comparison , Female , Geriatric Assessment/methods , Humans , Male , ROC Curve , Sensitivity and Specificity , Severity of Illness Index , TranslationsABSTRACT
Summary Objective: Translate, transcultural adaptation and application to Brazilian Portuguese of the Alzheimer's Disease Cooperative Study - Activities of Daily Living (ADCS-ADL) scale as a cognitive screening instrument. Method: We applied the back translation added with pretest and bilingual methods. The sample was composed by 95 elderly individuals and their caregivers. Thirty-two (32) participants were diagnosed as mild cognitive impairment (MCI) patients, 33 as Alzheimer's disease (AD) patients and 30 were considered as cognitively normal individuals. Results: There were only little changes on the scale. The Cronbach alpha coefficient was 0.89. The scores were 72.9 for control group, followed by MCI (65.1) and by AD (55.9), with a p-value < 0.001. The ROC curve value was 0.89. We considered a cut point of 72 and we observed a sensibility of 86.2%, specificity of 70%, positive predictive value of 86.2%, negative predictive value of 70%, positive likelihood ratio of 2.9 and negative likelihood ratio of 0.2. Conclusion: ADCS-ADL scale presents satisfactory psychometric properties to discriminate between MCI, AD and normal cognition.
Resumo Objetivo: Tradução, adaptação transcultural para o português brasileiro e aplicação da escala Alzheimer's Disease Cooperative Study - Activities of Daily Living (ADCS-ADL) como instrumento de triagem cognitiva. Método: Retrotradução associada ao método bilíngue e de pré-teste. A amostra foi constituída por 95 idosos e seus respectivos acompanhantes, sendo 30 controles, 32 portadores de comprometimento cognitivo leve (CCL) e 33 portadores de demência de Alzheimer (DA) em fase inicial. Resultados: Um pequeno número de modificações ocorreu na escala. O coeficiente alpha de Cronbach foi 0,89. O grupo controle pontuou 72,9, seguido pelo CCL (65,1) e pelo DA (55,9), valor p<0,001. A curva ROC demonstrou valor de 0,89. Com o ponto de corte de 72, observamos sensibilidade de 86,2%, especificidade de 70%, valor preditivo positivo de 86,2%, valor preditivo negativo de 70%, razão de verossimilhança positiva de 2,9 e razão de verossimilhança negativa de 0,2. Conclusão: A escala ADCS-ADL apresenta propriedades psicométricas satisfatórias para discriminar entre DA, CCL e cognição normal.
Subject(s)
Humans , Male , Female , Aged , Surveys and Questionnaires , Cognition Disorders/diagnosis , Translations , Severity of Illness Index , Brazil , Activities of Daily Living , Case-Control Studies , Geriatric Assessment/methods , Cross-Cultural Comparison , ROC Curve , Sensitivity and Specificity , Cognition Disorders/physiopathology , Alzheimer Disease/diagnosis , Alzheimer Disease/physiopathologyABSTRACT
Objective : The assessment of visuospatial abilities and memory using tasks such as the Taylor Complex Figure Task (TCFT) is biased for older adults with low formal education. We devised a "Simplified" version of the TCFT designed to assess older adults with low educational background and provide preliminary evidence of its psychometric properties. Methods : We evaluated a heterogeneous sample of healthy older adults and patients with mild cognitive impairment and Alzheimer's disease dementia using the simplified TCFT and other neuropsychological measures. Results : Our results suggest that the test copy, immediate and delayed recall have high inter-rater agreement and internal consistency, significant correlations with other tests of visuospatial abilities, memory and intelligence, and also detected significant group differences between controls and patients. Conclusion : Our study presents a new measure for assessing low-educated elderly with promising evidence of validity and reliability.
Objetivo : A avaliação de habilidades visioespaciais e de memória por tarefas como a Figura Complexa Taylor (FCT) é enviesada para de idosos com baixa escolarização formal. Propomos uma versão "simplificada" da FCT (FCTs) projetada para a avaliação dos idosos com baixo nível educacional e apresentamos evidências preliminares de suas propriedades psicométricas. Métodos : Avaliamos uma amostra heterogênea de idosos saudáveis e pacientes com comprometimento cognitivo leve e demência por Doença de Alzheimer usando a FCTs e outras medidas neuropsicológicas. Resultados : Nossos resultados sugerem que a cópia de teste, a evocação imediata e a evocação tardia têm alta concordância entre avaliadores e elevada consistência interna, apresentam correlações significativas com outros testes de habilidades visioespaciais, memória e inteligência, além de documentarem diferenças significativas entre o grupo controles e os pacientes. Conclusão : Nosso estudo apresenta uma nova medida para a avaliação neuropsicológica de idosos com baixa escolaridade, com evidências promissoras de validade e confiabilidade.
Subject(s)
Humans , Education , Alzheimer Disease , Cognitive Dysfunction , Neuropsychological TestsABSTRACT
OBJECTIVE: The assessment of visuospatial abilities and memory using tasks such as the Taylor Complex Figure Task (TCFT) is biased for older adults with low formal education. We devised a "Simplified" version of the TCFT designed to assess older adults with low educational background and provide preliminary evidence of its psychometric properties. METHODS: We evaluated a heterogeneous sample of healthy older adults and patients with mild cognitive impairment and Alzheimer's disease dementia using the simplified TCFT and other neuropsychological measures. RESULTS: Our results suggest that the test copy, immediate and delayed recall have high inter-rater agreement and internal consistency, significant correlations with other tests of visuospatial abilities, memory and intelligence, and also detected significant group differences between controls and patients. CONCLUSION: Our study presents a new measure for assessing low-educated elderly with promising evidence of validity and reliability.
OBJETIVO: A avaliação de habilidades visioespaciais e de memória por tarefas como a Figura Complexa Taylor (FCT) é enviesada para de idosos com baixa escolarização formal. Propomos uma versão "simplificada" da FCT (FCTs) projetada para a avaliação dos idosos com baixo nível educacional e apresentamos evidências preliminares de suas propriedades psicométricas. MÉTODOS: Avaliamos uma amostra heterogênea de idosos saudáveis e pacientes com comprometimento cognitivo leve e demência por Doença de Alzheimer usando a FCTs e outras medidas neuropsicológicas. RESULTADOS: Nossos resultados sugerem que a cópia de teste, a evocação imediata e a evocação tardia têm alta concordância entre avaliadores e elevada consistência interna, apresentam correlações significativas com outros testes de habilidades visioespaciais, memória e inteligência, além de documentarem diferenças significativas entre o grupo controles e os pacientes. CONCLUSÃO: Nosso estudo apresenta uma nova medida para a avaliação neuropsicológica de idosos com baixa escolaridade, com evidências promissoras de validade e confiabilidade.
ABSTRACT
BACKGROUND AND OBJECTIVES: The neuropsychological exam plays a central role in the assessment of elderly patients with cognitive complaints. It is particularly relevant to differentiate patients with mild dementia from those subjects with mild cognitive impairment. Formal education is a critical factor in neuropsychological performance; however, there are few studies that evaluated the psychometric properties, especially criterion related validity, neuropsychological tests for patients with low formal education. The present study aims to investigate the validity of an unstructured neuropsychological assessment protocol for this population and develop cutoff values for clinical use. METHODS AND RESULTS: A protocol composed by the Rey-Auditory Verbal Learning Test, Frontal Assessment Battery, Category and Letter Fluency, Stick Design Test, Clock Drawing Test, Digit Span, Token Test and TN-LIN was administered to 274 older adults (96 normal aging, 85 mild cognitive impairment and 93 mild Alzheimer`s disease) with predominantly low formal education. Factor analysis showed a four factor structure related to Executive Functions, Language/Semantic Memory, Episodic Memory and Visuospatial Abilities, accounting for 65% of explained variance. Most of the tests showed a good sensitivity and specificity to differentiate the diagnostic groups. The neuropsychological protocol showed a significant ecological validity as 3 of the cognitive factors explained 31% of the variance on Instrumental Activities of Daily Living. CONCLUSION: The study presents evidence of the construct, criteria and ecological validity for this protocol. The neuropsychological tests and the proposed cutoff values might be used for the clinical assessment of older adults with low formal education.
