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.

Influence of schooling and age on cognitive performance in healthy older adults

Few studies have examined the influence of a low level of schooling on age-related cognitive decline in countries with wide social and economic inequalities by using the Cambridge Automated Neuropsychological Test Battery (CANTAB). The aim of the present study was to assess the influence of schooling on age-related cognitive decline using unbiased cognitive tests. CANTAB allows cognitive assessment across cultures and education levels with reduced interference of the examiner during data acquisition. Using two-way ANOVA, we assessed the influences of age and education on test scores of old adults (61–84 years of age). CANTAB tests included: Visual Sustained Attention, Reaction Time, Spatial Working Memory, Learning and Episodic Memory. All subjects had a minimum visual acuity of 20/30 (Snellen Test), no previous or current history of traumatic brain/head trauma, stroke, language impairment, chronic alcoholism, neurological diseases, memory problems or depressive symptoms, and normal scores on the Mini Mental State Examination (MMSE). Subjects were grouped according to education level (1 to 7 and ≥8 years of schooling) and age (60–69 and ≥70 years). Low schooling level was associated with significantly lower performance on visual sustained attention, learning and episodic memory, reaction time, and spatial working memory. Although reaction time was influenced by age, no significant results on post hoc analysis were detected. Our findings showed a significantly worse cognitive performance in volunteers with lower levels of schooling and suggested that formal education in early life must be included in the preventive public health agenda. In addition, we suggest that CANTAB may be useful to detect subtle cognitive changes in healthy aging.

Association between depression severity and executive functioning in late-life depression: a systematic review / Associação entre a severidade dos sintomas depressivos e o funcionamento executivo de idosos com depressão: uma revisão sistemática

OBJECTIVE: Late-life depression is an under-diagnosed and under-treated disease that reduces the well-being of older adults. Executive dysfunction is another critical impairment in elderly depressed individuals which further disrupts their everyday functioning. This systematic review aims to analyze the association between executive function and depression severity in elderly individuals diagnosed with major depressive disorder. METHOD: The studies were retrieved from MEDLINE/PubMed, ISI Web of Knowledge and PsychInfo, after a search strategy combining the terms "depression", "executive function", "neuropsychological assessment", "elderly" and "late life". Study selection, data collection and quality ratings was performed by two independent raters. RESULTS: A total of 1,130 articles were found but only 8 studies met the defined eligibility criteria and evaluated the association between depression severity and executive functioning. Six out of 8 studies found an association between depression severity and executive function, with correlations ranging from small to large (r= -0.15 to -0.53). The included reports had several methodological limitations such as selective data reporting, non-comprehensive executive function assessment and not controlling potential biases. CONCLUSION: Depression severity may be more strongly correlated with a specific set of executive abilities although it also seems to be a broad-based association with executive functioning as a whole. Future high-quality prospective studies are recommended in order to understand the causal relationship between depression severity and executive functioning taking into account possible mediators such as age-related or neurodegenerative cognitive impairment, educational level and other clinic characteristics (e.g. age of onset, medication).

OBJETIVO: A depressão de início tardio é uma doença subdiagnosticada e subtratada que reduz o bem-estar da pessoa idosa. A disfunção executiva é outra alteração crítica em idosos deprimidos, perturbando ainda mais o seu funcionamento diário. Esta revisão sistemática tem como objetivo analisar a associação entre o funcionamento executivo e a severidade dos sintomas depressivos em idosos diagnosticados com transtorno depressivo major. MÉTODOS: Foi realizada uma busca nas bases de dados MEDLINE/PubMed, ISI Web of Knowledge e PsychInfo utilizando os termos "depression", "executive function", "neuropsychological assessment", "elderly" e "late life". A seleção, classificação dos estudos e coleta de dados foram realizadas por dois avaliadores independentes. RESULTADOS: Foram encontrados 1130 artigos, mas apenas 8 estudos preencheram os critérios de elegebilidade. Três avaliaram a associação entre a severidade dos sintomas e o funcionamento executivo. Seis dos 8 estudos encontraram uma associação entre a severidade dos sintomas e o funcionamento executivo, com correlações de diversas magnitudes (r= -0,15 a -0,53). Os artigos incluídos apresentaram várias limitações metodológicas, tais como descrição seletiva de dados, avaliação não compreensiva do funcionamento executivo e falha no controlo de possíveis vieses. CONCLUSÃO: A severidade dos sintomas depressivos pode ser fortemente correlacionada com um conjunto específico de habilidades executivas, embora pareça também existir uma associação mais ampla com o funcionamento executivo como um todo. Recomenda-se a realização de estudos prospetivos com o fim de compreender a relação causal entre a severidade dos sintomas depressivos e o funcionamento executivo, tendo em conta possíveis mediadores tais como défices cognitivos associados ao envelhecimento ou outros processos neuro-degenerativos, nível de escolaridade e outras características clínicas (idade de início da doença, medicação).

Atividades avançadas de vida diária e incidência de declínio cognitivo em idosos: Estudo SABE / Actividades avanzadas de la vida diaria y la incidencia de deterioro cognitivo en los ancianos: Estudio SABE / Advanced activities of daily living and incidence of cognitive decline in the elderly: the SABE Study

O objetivo deste trabalho foi avaliar o impacto das atividades avançadas de vida diária (AAVD) na incidência de declínio cognitivo. A amostra foi composta por idosos participantes do estudo longitudinal Saúde, Bem-estar e Envelhecimento (SABE). O declínio cognitivo foi avaliado por meio do Mini - Exame do Estado Mental abreviado. As AAVD compreenderam 12 atividades sociais, produtivas, físicas e de lazer que envolvem funções cognitivas superiores. Foram considerados grupos de covariáveis do estudo: fatores sociodemográficos, saúde geral, estilo de vida e funcionalidade. A associação entre a incidência de declínio cognitivo e as variáveis independentes foi avaliada usando-se o modelo de regressão de Poisson múltiplo. A incidência de declínio foi de 7,9%. A média de desempenho de AAVD em 2006 foi significativamente maior entre os idosos que não desenvolveram o declínio. Após análise multivariada os resultados mostraram que quanto maior o número de AAVD realizadas menor a chance de declínio cognitivo no período estudado.

El objetivo de este estudio fue evaluar el impacto de las actividades avanzadas de vida diaria (AAVD) en la incidencia del deterioro cognitivo. La muestra estuvo compuesta por ancianos participantes en el estudio longitudinal Salud, Bienestar y Envejecimiento (SABE). El deterioro cognitivo se evaluó mediante el Mini- Examen del Estado Mental abreviado. Las AAVD comprendieron 12 actividades sociales, productivas, físicas y de ocio que involucran funciones cognitivas superiores. Se consideraron grupos de covariables del estudio: factores sociodemográficos, salud general, estilo de vida y funcionalidad. La asociación entre la incidencia de deterioro cognitivo y las variables independientes fue evaluada mediante la plantilla de regresión de Poisson múltiple. La incidencia de deterioro fue de un 7,9%. La media de desempeño de AAVD en 2006 fue significativamente mayor entre los ancianos que no desarrollaron el deterioro. Después de un análisis multivariado los resultados mostraron que cuanto mayor es el número de AAVD, más pequeña es la incidencia del deterioro cognitivo en el periodo estudiado.

The objective of this study was to evaluate the association between advanced activities of daily living (AADL) and incidence of cognitive decline. The sample consisted of non-institutionalized older adults who participated in the second (2006) and third (2010) waves of the Health, Wellbeing, and Aging (SABE) cohort study in São Paulo, Brazil. Cognitive decline was measured using a modified Mini-Mental State Examination. Advanced activities of daily living covered 12 social, productive, physical, and leisure-time activities that involve higher cognitive functions. Other covariates included socio-demographic conditions, overall health, lifestyle, and functional disability. The association between the independent variables and incidence of cognitive decline was assessed by multiple Poisson regression. Incidence of cognitive decline was 7.9%. Mean number of AADL in 2006 was significantly higher among elders who had not developed cognitive decline. Multivariate analysis showed that the number of AADL performed was a significant inverse predictor of cognitive decline.