Prevalence of cognitive impairment in Brazilian indigenous community from Amazonas / Prevalência de comprometimento cognitivo em indígenas brasileiros do amazonas

ABSTRACT. Studies on the prevalence of dementia in the indigenous population are still scarce worldwide. In the few available studies, prevalence evidence varies from low to very high, with early onset of the disease and high mortality rate after the initial diagnosis. Still, little is known about the rate of dementia in indigenous populations from low- and middle-income countries, where the dementia prevalence in the general population is estimated to increase significantly in the next decades. Objective: This study aimed to determine the prevalence of cognitive impairment and associated factors in Brazilian indigenous people of the Mura ethnicity in Amazonas, Brazil. Methods: A total of 217 indigenous individuals aged 50 years and older from Amazonas, Brazil, were submitted to cognitive assessment. Attention, memory, verbal fluency, visuospatial performance, and mood state composed the cognitive impairment diagnosis. Results: The prevalence of cognitive impairment was 43.3% (95%CI 36.6-49.7) and varied according to age [OR=1.03 (95%CI 1.00-1.06)], education [OR=0.74 (95%CI 0.62-0.87)], body mass index [OR=0.91 (95%CI 0.83-0.98)], and income [OR=0.52 (95%CI 0.27-0.99)]. Conclusions: Cognitive impairment had an early onset in an indigenous community, and its prevalence was greater in older individuals with low education and low family income. These findings highlight the importance of implementing public indigenous health policies focusing on health professional training for early cognitive impairment detection.

RESUMO. No mundo, estudos sobre a prevalência de demência em idosos indígenas são insuficientes, porém nas evidências disponíveis, a prevalência varia de baixa a muito alta, com início precoce da doença e elevada taxa de mortalidade após o diagnóstico inicial. As evidências em países de baixa e média renda são escassas, e neles a prevalência de demência aumentará significativamente nas próximas décadas. Objetivo: Determinar a prevalência de déficit cognitivo e fatores associados em indígenas brasileiros da etnia Mura no Amazonas, Brasil. Métodos: Duzentos e dezessete indígenas com 50 anos ou mais do Amazonas, Brasil, foram submetidos a avaliação cognitiva. Atenção, memória, fluência verbal, desempenho visuoespacial e estado de humor compuseram o diagnóstico de déficit cognitivo. Resultados: A prevalência de déficit cognitivo foi de 43,3% (intervalo de confiança - IC95% 36,6-49,7) e variou de acordo com a idade [odds ratio - OR=1,03 (IC95% 1,00-1,06)], educação [OR=0,74 (IC95% 0,62-0,87)], índice de massa corporal [OR=0,91 (IC95% 0,83-0,98)] e renda [OR=0,52 (IC95% 0,27-0,99)]. Conclusões: O comprometimento cognitivo teve início precoce na comunidade indígena, sendo sua prevalência maior em idosos com baixa escolaridade e baixa renda familiar. Esses achados destacam a importância da implementação de políticas públicas de saúde indígena, com foco na formação de profissionais de saúde, para a detecção precoce do déficit cognitivo.

Does brain creatine content rely on exogenous creatine in healthy youth? A proof-of-principle study.

It has been hypothesized that dietary creatine could influence cognitive performance by increasing brain creatine in developing individuals. This double-blind, randomized, placebo-controlled, proof-of-principle study aimed to investigate the effects of creatine supplementation on cognitive function and brain creatine content in healthy youth. The sample comprised 67 healthy participants aged 10 to 12 years. The participants were given creatine or placebo supplementation for 7 days. At baseline and after the intervention, participants undertook a battery of cognitive tests. In a random subsample of participants, brain creatine content was also assessed in the regions of left dorsolateral prefrontal cortex, left hippocampus, and occipital lobe by proton magnetic resonance spectroscopy (1H-MRS) technique. The scores obtained from verbal learning and executive functions tests did not significantly differ between groups at baseline or after the intervention (all p > 0.05). Creatine content was not significantly different between groups in left dorsolateral prefrontal cortex, left hippocampus, and occipital lobe (all p > 0.05). In conclusion, a 7-day creatine supplementation protocol did not elicit improvements in brain creatine content or cognitive performance in healthy youth, suggesting that this population mainly relies on brain creatine synthesis rather than exogenous creatine intake to maintain brain creatine homeostasis.

Performance of a sample of patients with Mild Cognitive Impairment (MCI), Alzheimer's Disease (AD) and healthy elderly on a lexical decision test (LDT) as a measure of pre-morbid intelligence / Desempenho de uma amostra de pacientes com Comprometimento Cognitivo Leve (CCL), doença de Alzheimer (DA) e idosos saudáveis em Teste de Decisão Lexical (TDL) como medida de QI pré-mórbido

Objective:The objective of this study was to describe the performance of healthy elderly patients with aging-related pathologies (MCI) and patients with AD on a lexical decision test.Methods:The study included 38 healthy elderly subjects, 61 MCI and 26 AD patients from the Neurology Department of the Hospital das Clinicas, Behavioral and Cognitive Neurology Group. The neuropsychological instruments included the episodic memory test (RAVLT), subtests from the WAIS-III (Matrix Reasoning and Vocabulary) to determine estimated IQ, the Boston naming test (BNT) and Lexical Decision Test (LDT).Results:All groups differed on the MMSE, as expected according to their pathologies, memory tests, naming and estimated IQ. For the vocabulary and the LDT - measures of crystalized intelligence no differences were found.Conclusion:The LDT demonstrated that lexical decision can be used as a measure of pre-morbid IQ among the individuals assessed in a Brazilian sample.

Objetivo:O objetivo deste artigo é descrever o desempenho de idosos saudáveis, idosos com patologias relacionadas ao envelhecimento (CCL) e de idosos com DA, em teste de decisão lexical.Métodos:Participaram 38 idosos saudáveis, 61 CCL e 26 DA, atendidos no Setor de Neurologia do Hospital das Clínicas (GNCC) e do Centro de Referência em Distúrbios Cognitivos (CEREDIC). Os instrumentos neuropsicológicos incluíram teste de memória episódica (RAVLT), Subtestes do WAIS-III (Vocabulário e Raciocínio Matricial) para estabelecer QI estimado, teste de nomeação (BNT) e o Teste de Decisão Lexical (TDL).Resultados:Todos os grupos diferiram quanto ao MEEM, de acordo com o esperado para as patologias, para os testes de memória, para a nomeação e o QI estimado. No caso do vocabulário e do TDL - medidas de inteligência cristalizada não apresentaram diferença.Conclusão:O TDL permitiu que se mostrasse que a decisão lexical pode ser uma medida de QI pré-mórbido nos indivíduos avaliados em uma amostra da população brasileira.