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Background Healthy brain aging can be defined as aging without neurological or psychiatric disorders, sustaining functional independence. In addition to the absence of disease and preserved functionality, there are individuals who stand out for their superior performance to that considered normal for their age in cognitive tests. These individuals are called “high-performance older adults” (HPOA). Objectives To investigate the presence of HPOA in an oldest-old population with low education, and if present, to investigate associations with sociodemographic, clinical, and lifestyle variables. Methods We evaluated 132 cognitively healthy individuals from the Pietà Study, a population-based investigation with 639 participants. We used the delayed recall from the Rey Auditory-Verbal Learning Test to verify the existence of HPOA and to classify participants based on their performance. Sociodemographic, clinical, and lifestyle variables associated with HPOA were investigated. Results We identified 18 individuals fulfilling HPOA criteria (age: 77.4 ± 2.6 years old; 14 women; education: 4.6 ± 3.4 years). The other participants, 114 total (age: 79.8 ± 4.5 years old; 69 women; education: 3.0 ± 2.7 years) were classified as “standard performance older adults” (SPOA). In multivariate analysis, younger age (odds ratio [OR] = 0.672; 95% confidence interval [CI]: 0.462–0.979; p = 0.037) and lower scores on the Geriatric Depression Scale (OR = 0.831; 95%CI: 0.688–0.989; p = 0.038) were associated with HPOA. Conclusions The present study identifies for the first time HPOA with low educational level, thereby reinforcing the existence of biological substrates related to this condition. Furthermore, the data suggest an association between younger age and less depressive symptoms with HPOA.

In developing countries, cardiovascular risk factors are poorly controlled, leading to high prevalence of cerebrovascular diseases. The aim of the study was to evaluate the burden of white matter lesions in magnetic resonance through the Fazekas scale in a population aged 75+ years living in the community, and to investigate possible associations between vascular lesions, cardiovascular risk factors and cognitive status. Subjects were selected from a community-based study on brain aging conducted in Caeté (Minas Gerais state), Brazil. Overall, 177 participants (112 cognitively healthy, 36 with cognitive impairment-no dementia and 29 with dementia), being 108 women, aged 79.3 ± 3.8 years, with 3.1 ± 2.9 years of educational level, underwent a 3 Tesla magnetic resonance scanner with fluid attenuated image recovery acquisition. Severity of white matter lesions was assessed through the Fazekas scale. Severe white matter lesions were present in 31.1% of the whole sample and in 25.0% of the cognitively healthy individuals. A significant association was found between severe white matter lesions and cognitive impairment (OR = 2.20, 95% CI 1.17–6.53; p = 0.021), as well as with hypertension (OR = 1.92, 95% CI 1.03–7.39; p = 0.043). In conclusion, a high prevalence of severe white matter lesions was observed in this elderly Brazilian population sample, and white matter lesions were associated with hypertension and cognitive status. Importantly, the prevalence of white matter lesions was also high in cognitively healthy subjects. Keywords: White matter lesions, Aging, Dementia, Hypertension

According to the cognitive reserve theory, intellectual stimuli acquired during life can prevent against developing cognitive impairment. The underlying cognitive reserve mechanisms were underexplored in low-educated individuals. Because episodic memory impairment due to hippocampal dysfunction is a key feature of Alzheimer’s dementia (AD), we sought to look at a possible cognitive reserve mechanism by determining whether few years of education moderated the relationship between the hippocampal volumes and the episodic-memory scores. The sample was composed by 183 older adults, 40.1% male, with the median age of 78[76,82] years and the median years of education of 4[2,10] who had undergone an episodic-memory test and a 3-Tesla MRI scan to access the hippocampal volumes. Overall, 112 were cognitively healthy, 26 had cognitive impairment-no dementia (CIND) and 45 had dementia. We used multiple linear regression to assess whether the interaction between years of education and each hippocampal volume significantly predicted the episodic-memory scores’ variance, controlling for cognitive diagnosis and nuisance variables. The interaction term with the left hippocampus (ß = 0.2, p = 0.043, CI = 1.0, 1.4), but not with the right (ß = 0.1, p = 0.218, CI = 0.9, 1.2) significantly predicted the variation on memory scores. The mechanism by which the left hippocampus seems to play a more important role on memory processing in more educated individuals needs to be further investigated and might be associated with a better use of mnemonic strategies or higher hippocampal connectivity. Because the sample’s median years of education was four, which corresponds to primary school, we may infer that this level might be sufficient to contribute for building cognitive reserve.

ABSTRACT The low-educated elderly are a vulnerable population in whom studying the role of white matter integrity on memory may provide insights for understanding how memory declines with aging and disease. Methods: Thirty-one participants (22 women), 23 cognitively healthy and eight with cognitive impairment-no dementia, aged 80.4 ± 3.8 years, with 2.2 ± 1.9 years of education, underwent an MRI scan with diffusion tensor imaging (DTI) acquisition. We verified if there were correlations between the performance on the Brief Cognitive Screening Battery (BCSB) and the Rey Auditory Verbal Learning Test (RAVLT) with DTI parameters. Results: The BCSB delayed recall task correlated with frontotemporoparietal connection bundles, with the hippocampal part of the cingulum bilaterally and with the right superior longitudinal fasciculus. The RAVLT learning and delayed recall scores also correlated with the hippocampal part of the cingulum bilaterally. Conclusions: Although preliminary, our study suggests that the integrity of white matter frontotemporoparietal fasciculi seems to play a role in episodic memory performance in the low-educated elderly. This finding opens opportunities to study potential targets for memory decline prevention in vulnerable populations.

Abstract Introduction Late-life depression (LLD) is common, but remains underdiagnosed. Validated screening tools for use with the oldest-old in clinical practice are still lacking, particularly in developing countries. Objectives To evaluate the accuracy of a screening tool for LLD in a community-dwelling oldest-old sample. Methods We evaluated 457 community-dwelling elderly subjects, aged ≥75 years and without dementia, with the Geriatric Depression Scale (GDS-15). Depression diagnosis was established according to DSM-IV criteria following a structured psychiatric interview with the Mini International Neuropsychiatric Interview (MINI). Results Fifty-two individuals (11.4%) were diagnosed with major depression. The area under the receiver operating characteristic (ROC) curve was 0.908 (p

ABSTRACT Recently, there has been an increasing number of studies on exceptional cognitive aging. Herein, we aim to objectively provide the operationalized characterization of older adults with unusually high memory ability. Some authors have defined them as “SuperAgers”, individuals aged 80 years or older with memory ability similar or superior to middle-aged subjects. On the other hand, the terminology “high-performing older adults” (HPOA) seems to appropriately conceptualize these individuals without exaggeration. A threshold for age is not a reliable criterion, but may be defined as 75 and 80 years of age for developing and developed countries, respectively. We propose that HPOA may exhibit episodic memory test scores equal to or greater than those of individuals aged 50-60 years, according to the validated tables for the respective country. This group must also have global cognition scores within expected average values for age and education. Executive functioning may play a central role in the exceptional memory performance of this group. Further studies are essential to confirm existing findings and may provide important evidence for cognitive aging theory and the neurobiology of dementia.