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Background: The link between sarcopenia and cognitive impairment has not yet been thoroughly evaluated, especially among older adults. Objective: To evaluate the relationship between probable sarcopenia and cognitive impairment among community-dwelling older adults in two Brazilian cities. Methods: Probable sarcopenia was assessed using the EWGSOP2 (2018) criteria. Thus, participants were classified as probably having sarcopenia if they had SARC-F (Strength, Assistance in walking, Rise from a chair, Climb stairs and Falls) ≥4 points and low grip strength. Cognitive function was evaluated through the Mini-Mental State Examination (MMSE), verbal fluency (VF) and clock drawing test (CDT). Results: In a sample of 529 older adults (mean age 80.8±4.9 years; mean education 4.2±3.67 years; 70.1% women), 27.3% of the participants had SARC-F≥4, 38.3% had low grip strength and 13.6% were classified as probable sarcopenia cases. After adjusting for possible confounders (age, sex, education, depression, diabetes, hypertension, leisure-time physical activity and obesity), probable sarcopenia was found to be associated with impairment in the MMSE (OR 2.52; 95%CI 1.42‒4.47; p=0.002) and in VF (OR 2.17; 95%CI 1.17‒4.01; p=0.014). Low grip strength was found to be associated with impairment in the MMSE (OR 1.83; 95%CI 1.18‒2.82; p=0.006) and in the CDT (OR 1.79; 95%CI 1.18‒2.73; p=0.006). SARC-F scores were found to be associated with impairment in the MMSE (OR 1.90; 95%CI 1.18‒3.06; p=0.008). Conclusion: The results suggested that probable sarcopenia and its components present a significant association with cognitive deficits among community-dwelling older adults. Future longitudinal studies will further explore the causal relationship.

Alzheimer’s disease (AD) is associated with a progressive dementia, and there is good evidence that it is more pronounced in individuals that have fewer stimuli during their lives. Environmental stimulation promotes morphological and functional changes in the brain, leading to amplification of cognitive functions, and has been described in humans and animals. In this study, we evaluated the effects of enriched environment (EE) stimulation on spatial memory and senile plaque formation in transgenic mice PDGFB-APPSwInd (TG) that overexpress the human amyloid precursor protein, normally resulting in an increased density of senile plaques. We compared this group of EE stimulated transgenic mice (TG-EE) with an EE stimulated control group of age-matched C57Bl/6 wild type animals (WT-EE). Both groups were exposed to EE stimulation between the ages of 8 and 12 months. As controls of the experiment, there were a group of TG mice not exposed to EE (TG-Ctrl) and a group of WT mice not exposed to EE (WT-Ctrl). The TG-EE group presented improved spatial memory when compared to the TG-Ctrl animals. In addition, the TG-EE group showed a 69.2% reduction in the total density of senile plaques in the hippocampus when compared to the TG-Ctrl group. In this group, the concentration of senile plaques was greater in the dorsal part of the hippocampus, which is linked to spatial localization, and the reduction of this density after the submission to EE was as high as 85.1%. EE stimulation had no effect on the density of amyloid-β (Aβ) oligomers. However, amyloid scavenger receptor class B member 1 (SR-B1) density was significantly decreased in the TG-Ctrl mice, but not in the TG-EE mice, suggesting that cognitive stimulation had an effect on the formation of a cognitive reserve that could prevent the accumulation of senile plaques. It is suggested that the stimulation of old mice by EE for 4 months led to the formation of brain resilience that protected the brain from the deposition of senile plaques, one of the hallmarks of AD, leading to improvement in spatial memory.

Objectives: Frailty is characterized by a functioning decline in multiple systems accompanied by an increase in individual's vulnerability to stressors. It appears to be higher in low and middle-income countries compared with high-income ones. This study aimed to evaluate the prevalence of frailty in non-institutionalized Brazilian older adults. Design: a systematic review and meta-analysis study. Setting: Cross-sectional and prospective data from Brazil. Participants: non-institutionalized adults aged 60 and older. Methods: Electronic searches were performed in PubMed/MEDLINE, LILACS, SCOPUS and Web of Science, considering the studies published between March 2001 and July 2018, using a combination of the following terms and correlates: "elder" AND "frail" AND "prevalence" AND "Brazil". Two independent reviewers selected studies according to the inclusion criteria. Disagreements were resolved by a third reviewer (title/abstract) and by consensus. Studies with samples ≥221 subjects were considered for meta-analysis. Results: 28 studies were included, while 18 had the data meta-analyzed. The majority of studies (61%) included older adults only from the Southeastern region. The number of subjects ranged from 53 to 5,532 individuals (N = 17,604) and the average age ranged from 65.6 to 85.5 years. The overall prevalence of frailty was 24%. When considering the different assessment methods, the prevalence was lower for frailty phenotype (16%) compared with other criteria (40%). Regarding sex, the prevalence of frailty was similar for women (28%) and men (25%). The prevalence of frailty was higher in older adults recruited from health care services (30%) compared to community ones (22%). Conclusion: In Brazil, the overall prevalence of frailty in non-institutionalized older adults is higher than observed from more developed countries. However, it may vary according to the assessment methods and settings.

Resumo Objetivo Investigar e comparar o perfil sociodemográfico, cognitivo e de fragilidade dos participantes do Estudo Fragilidade em Idosos Brasileiros em medidas de seguimento (SG) e linha de base (LB) realizadas em 2016-2017 e 2008-2009, respectivamente. Métodos Participaram da LB 1.284 idosos residentes em Campinas e Ermelino Matarazzo (SP), Brasil, que compuseram amostra única. No SG foram novamente entrevistados 549 participantes (42,5%); 192 tinham falecido (14,9%) e 543 foram perdidos (42,4%). Em ambos os momentos, foram avaliadas as variáveis sexo, idade, escolaridade, estado conjugal, renda familiar, arranjo de moradia, status cognitivo (Mini-Exame do Estado Mental) e fenótipo de fragilidade (três ou mais de cinco critérios). As diferenças intergrupos e intragrupos foram verificadas pelos testes qui-quadrado de Pearson e de McNemar, respectivamente. O nível de significância foi estabelecido em p<0,05. Resultados Entre os sobreviventes, os participantes eram mais jovens (72,2±5,3 anos) do que entre os falecidos (75,5±6,8 anos) e havia mais idosos casados, com nível educacional mais elevado, sem deficit cognitivo e pré-frágeis. Da LB para o SG, houve aumento estatisticamente significativo do número de idosos que moravam sozinhos (17,1% vs. 22,0%), não tinham companheiro(a) (46,4% vs. 55,4%), tinham renda familiar menor que três salários-mínimos (52,2% vs. 62,2%), apresentavam deficit cognitivo (17,7% vs. 23,5%) e eram frágeis (9,8% vs. 24,5%) Conclusão Da LB para o SG, ocorreu aumento da vulnerabilidade física, cognitiva e social dos idosos. Estes resultados reforçam a importância de políticas públicas que favoreçam a qualidade de vida dos idosos e a redução das iniquidades de saúde ao longo da vida.