Rural-urban disparities in fruit and vegetable consumption and cognitive performance in Brazil

Objectives: Rural residents are exposed to many risk factors for poor diet quality, such as low socioeconomic status and food insecurity. However, the differences between urban and rural residents regarding the association of fruit and vegetable consumption with cognitive performance have not been explored. The aim of this study was to investigate the association of fruit and vegetable consumption with cognitive performance in urban and rural areas in a nationally representative sample of Brazilian older adults. Methods: The sample included 9,412 adults aged 50 years or older from the Brazilian Longitudinal Study of Aging (Estudo Longitudinal da Saúde dos Idosos Brasileiros [ELSI]). The association between consumption of fruits and vegetables and cognitive performance was evaluated using linear regression. Results: In 8,158 participants (mean age 61.6 ± 9.3 years, 54% women, 44% White, and 15% from rural areas), the mean frequency of fruit and vegetable consumption was 2.0 ± 1.3 times a day. Higher intake of fruits and vegetables was associated with better memory (β = 0.031, 95%CI 0.014-0.049), verbal fluency (β = 0.030, 95%CI 0.004-0.056), and global cognition (β = 0.035, 95%CI 0.015-0.055) performance in urban, but not rural residents (p for interaction = 0.036). Conclusion: Higher frequency of fruit and vegetable intake was associated with better cognitive performance in urban, but not in rural areas in Brazil.

Retest effects in a diverse sample: sociodemographic predictors and possible correction approaches / Efeito de reteste em uma amostra diversa: preditores sociodemográficos e possíveis abordagens para a correção

ABSTRACT. Repeated cognitive assessment in longitudinal studies favors the occurrence of retest effects, usually increasing the scores obtained at the follow-up assessments when compared to baseline. Therefore, retest effects can compromise the evaluation of cognitive decline in older adults. Objectives: We aimed to verify the occurrence of the retest effect and the impact of sociodemographic characteristics on the follow-up scores in a sample of 5,592 participants with a diverse sociodemographic profile, who were assessed twice during 4 years of follow-up. Methods: We tested two possible approaches to correct the retest effect and calculated the Reliable Change Index. Results: We observed increased scores at the follow-up assessment after 4 years, but the results indicate a modest occurrence of retest effects. The regression difference correction successfully generated follow-up corrected scores, while the mean difference did not provide effective corrections. Sociodemographic characteristics had a minor impact on the retest. Conclusions: We recommend the regression difference correction for retest effects. The absence of this methodological approach might lead to biased results using longitudinal cognitive scores.

RESUMO. Avaliações cognitivas repetidas em estudos longitudinais favorecem a ocorrência de efeitos de retestagem ou de prática, geralmente aumentando os escores obtidos nas avaliações de acompanhamento quando comparados aos da primeira avaliação. Sendo assim, os efeitos do retestagem podem comprometer a verificação do declínio cognitivo em idosos. Objetivos: Objetivamos verificar a ocorrência do efeito de prática e o impacto das características sociodemográficas nos escores de seguimento em uma amostra de 5.592 participantes com perfil sociodemográfico diverso, avaliada duas vezes durante quatro anos de seguimento. Métodos: Testamos duas abordagens possíveis para corrigir o efeito de prática e calculamos o índice de mudança confiável. Resultados: Observamos escores sutilmente maiores na avaliação de seguimento após quatro anos, o que sugere a ocorrência de efeitos de retestagem. A correção pela diferença da regressão gerou escores corrigidos de acompanhamento satisfatórios, enquanto a correção pela diferença média não forneceu correções eficazes. As características sociodemográficas tiveram impacto mínimo no efeito de prática. Conclusões: Recomendamos a forma de correção pela diferença da regressão para efeitos de retestagem. A ausência dessa abordagem metodológica, quando utilizamos escores cognitivos longitudinais, pode levar a resultados enviesados.

Longitudinal measurement invariance of neuropsychological tests in a diverse sample from the ELSA-Brasil study

Objective: Longitudinal measurement invariance analyses are an important way to assess a test's ability to estimate the underlying construct over time, ensuring that cognitive scores across visits represent a similar underlying construct, and that changes in test performance are attributable to individual change in cognitive abilities. We aimed to evaluate longitudinal measurement invariance in a large, social and culturally diverse sample over time. Methods: A total of 5,949 participants from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) were included, whose cognition was reassessed after four years. Longitudinal measurement invariance analysis was performed by comparing a nested series of multiple-group confirmatory factor analysis models (for memory and executive function factors). Results: Configural, metric, scalar and strict invariance were tested and supported over time. Conclusion: Cognitive temporal changes in this sample are more likely to be due to normal and/or pathological aging. Testing longitudinal measurement invariance is essential for diverse samples at high risk of dementia, such as in low- and middle-income countries.

Semantic memory, but not education or intelligence, moderates cognitive aging: a cross-sectional study

Objective: Aging studies regularly assume that years of education are a protective factor for baseline cognition. In developing countries with specific sociocultural issues, this relationship may not work as expected, and an unmet need remains for alternative resilience factors. This study aimed to analyze different moderators for the relationship between aging and general cognition that could reflect better protective factors. Methods: One hundred and fourteen Brazilian older adults, deemed healthy by global cognition, absence of psychiatric symptoms, or neurological history, participated in this cross-sectional study. Moderators for the relationship between age and global cognition included education, intelligence, and occupational factors. Semantic memory was added as a protective factor reflecting culturally acquired conceptual knowledge. Results: As expected, age alone is a predictor of global cognitive scores; surprisingly, however, education, intelligence, and occupation were not moderators of the association. Semantic memory was a significant moderator (p = 0.007), indicating that knowledge acquired during life may be a protective factor. Conclusion: In developing countries, the use of resilience factors based only on years of education may be misleading. Sociocultural issues influence the educational system and achievement and, consequently, affect the use of this simple measure. Resilience-factor studies should consider using crystallized abilities when studying populations with sociocultural particularities.

Plasma IL-17A levels in patients with late-life depression

Objective: A consistent body of research has confirmed that patients with major depressive disorder (MDD) have increased concentrations of pro-inflammatory cytokines, including IL-6, TNF-α, IL-1β, the soluble IL-2 receptor, and C-reactive protein, compared to controls; however, there is limited information on IL-17A in MDD. Moreover, information about IL-17A in older populations, i.e., patients with late-life depression (LLD), is conspicuously missing from the literature. The purpose of this study was to investigate the role of IL-17A in LLD. Methods: A convenience sample of 129 individuals, 74 with LLD and 55 non-depressed controls, were enrolled in this study. The Mann-Whitney U test was used to compare plasma IL-17A levels between LLD and controls subjects, and Spearman's rank order correlation was used to investigate correlation of these levels with clinical, neuropsychological, and cognitive assessments. Results: Plasma IL-17A levels were not statistically different between LLD patients and controls (p = 0.94). Among all subjects (LLD + control), plasma IL-17A did not correlate significantly with depressive symptoms (rho = -0.009, p = 0.92) but a significant correlation was observed with cognitive assessments (rho = 0.22, p = 0.01). Conclusion: Our findings do not support an association between plasma IL-17A levels and LLD. Nevertheless, IL-17A may be associated with cognitive impairment in LLD patients. If this finding is confirmed in future longitudinal studies, modulation of the T-helper 17 cell (Th17) immune response may be a treatment target for cognitive impairment in this population.

Assessing knowledge: psychometric properties of the BAMS semantic memory battery

Abstract Background: Semantic memory is a cultural influenced cognitive domain that is responsible for our knowledge about words and the world. Semantic Memory Battery (BAMS) is a new battery that evaluate semantic memory based on a compendium of tasks, including verbal fluency, naming, conceptualization, categorization, general questions, and word definitions, and was designed to consider cultural aspects. Objectives: We aimed to evaluate the BAMS psychometrics structure comprising classical and modern analysis, and also evaluate a clinical subdivision of the battery. Methods: 114 Brazilian cognitively healthy older adults BAMS performance provided data for psychometric analysis using validity tests, item response theory analysis and confirmatory factor analysis for goodness-of-fit measures. Results: BAMS results revealed good validity and good-fit measures in each subtest, total score (X2 = 20.684, p = 0.110) and a hierarchical structure with clinical subdivision of the battery (X2 = 20.089, p = 0.093). Discussion: BAMS is a new compendium of tasks that evaluate distinct aspects of semantic memory and can clinically consider the impact of executive function. This battery evaluates verbal fluency, naming, conceptualization, categorization, general knowledge and word definitions. The BAMS has clinical importance once semantic memory is mostly influenced by culture and language, and there is an absence of broadly semantic memory tests in our scenario, especially with older adults that can have a pathological aging condition that affects primarily or secondarily this domain.

Functional decline in the elderly with MCI: Cultural adaptation of the ADCS-ADL scale / Declínio funcional em idosos com comprometimento cognitivo leve: adaptação cultural da escala ADCS-ADL

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.

Development, validity, and reliability of the General Activities of Daily Living Scale: a multidimensional measure of activities of daily living for older people

Objective: To propose and evaluate the psychometric properties of a multidimensional measure of activities of daily living (ADLs) based on the Katz and Lawton indices for Alzheimer's disease (AD) and mild cognitive impairment (MCI). Methods: In this study, 85 patients with MCI and 93 with AD, stratified by age (≤ 74 years, > 74 years), completed the Mini Mental State Examination (MMSE) and the Geriatric Depression Scale, and their caregivers completed scales for ADLs. Construct validity (factor analysis), reliability (internal consistency), and criterion-related validity (receiver operating characteristic analysis and logistic regression) were assessed. Results: Three factors of ADL (self-care, domestic activities, and complex activities) were identified and used for item reorganization and for the creation of a new inventory, called the General Activities of Daily Living Scale (GADL). The components showed good internal consistency (> 0.800) and moderate (younger participants) or high (older participants) accuracy for the distinction between MCI and AD. An additive effect was found between the GADL complex ADLs and global ADLs with the MMSE for the correct classification of younger patients. Conclusion: The GADL showed evidence of validity and reliability for the Brazilian elderly population. It may also play an important role in the differential diagnosis of MCI and AD. .

Evaluating Language Comprehension in Alzheimer's disease: the use of the Token Test / Avaliação da compreensão da linguagem na doença de Alzheimer: o uso do Token Test

OBJECTIVE: To analyze the psychometric properties of the Token test (TT), a verbal comprehension test, and its applicability to the diagnosis of mild Alzheimer's disease (AD). METHODS: One hundred and sixty participants (80 AD and 80 controls) performed the TT and a short battery of neuropsychological tests designed to evaluate general cognitive status, working memory and executive functions. Internal consistency, factor structure, correlation with other measures and group comparisons were evaluated. RESULTS: The test evinced good internal consistency and a bi-factorial structure (related to comprehension and attention). Differences between AD and controls were significant, however the TT presented only moderate sensitivity and specificity for the AD diagnosis. CONCLUSION: The TT showed evidence of good psychometric properties and adequacy for characterizing comprehension deficits in AD, but it was not an appropriate test for the AD detection and diagnosis.

OBJETIVO: Investigar as propriedades psicométricas do Token test (TT), um teste de compreensão verbal, e sua aplicabilidade no diagnóstico da doença de Alzheimer em fase inicial (DA). MÉTODOS: Cento e sessenta participantes (80 DA e 80 controles) foram avaliados por meio do TT e de testes neuropsicológicos que avaliam a cognição geral, memória operacional e funções executivas. Avaliou-se a consistência interna, correlações com outros testes neuropsicológicos, estrutura fatorial e poder diagnóstico do TT. RESULTADOS: O teste apresenta boa consistência interna e estrutura bi-fatorial (relacionada à compreensão e atenção). Foram encontradas diferenças significativas entre o desempenho de DA e dos controles. Contudo, a sensibilidade e especificidade do TT para o diagnóstico de DA foi apenas moderada. CONCLUSÃO: O TT apresenta boas propriedades psicométricas e mostra-se adequado para a caracterização de comprometimentos de linguagem na DA. Entretanto, nossos resultados sugerem que o teste por si só é insuficiente para a detecção e diagnóstico dessa demência.