Ana Luisa Sosa

Introduction/Objective: Primary progressive aphasia (PPA) is a clinical syndrome characterized by progressive language impairment. Three subtypes have been identified: semantic (svPPA), nonfluent (nfPPA), and logopenic (lvPPA). Although clinical criteria exist to classify these subtypes, the specific ways in which semantic cognition is impaired across these variants have not yet been fully elucidated. This cross-sectional study aimed to analyze the effects of cognitive demand and imaginability on semantic cognition in patients with PPA. Methods: Fifteen patients with PPA (five per variant) and 20 healthy controls completed a semantic association task comprising 20 items. The task included two levels of cognitive demand (low and high) and two types of concepts (concrete and abstract). Participants selected the word with the strongest semantic link to a probe word, based on synonymy, categorical relations, or shared features. Accuracy and reaction times were recorded and analyzed using nonparametric statistics. Results: All PPA groups performed significantly worse than controls, showing fewer correct responses and longer reaction times. svPPA patients exhibited the greatest impairment across all conditions. nfPPA patients performed similarly to controls with concrete concepts but showed deficits with abstract words. lvPPA patients experienced greater difficulty under high cognitive demand, particularly with abstract words, indicating impaired semantic control. Discussion: These findings suggest that svPPA is characterized by global impairment of conceptual knowledge, whereas nfPPA and lvPPA exhibit more selective deficits depending on concept type and cognitive demand. Conclusion: The research herein highlights the importance of considering cognitive demand and imaginability when assessing semantic cognition in PPA.

In amnestic mild cognitive impairment (aMCI), neuroinflammation evolves during disease progression, affecting microglial function and potentially accelerating the pathological process. Currently, no effective treatment exists, leading to explorations of various symptomatic approaches, though few target the underlying physiological mechanisms. Modulating inflammatory processes may be critical in slowing disease progression. Cognitive stimulation (CS) and transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal cortex (l-DLPFC) show promise, but the results are heterogeneous. Thus, a randomized, double-blind, placebo-controlled clinical trial is currently underway. The first-stage results were examined after three weeks of intervention in two groups: active tDCS combined with CS and sham tDCS combined with CS. Twenty-two participants underwent two assessments: T0 (baseline) and T1 (after 15 sessions of tDCS, active or sham, and 9 sessions of CS). The results demonstrated that CS improved cognition, increased brain-derived neurotrophic factor (BDNF) levels, and reduced peripheral proinflammatory cytokine levels (interleukin IL-6 and chemokine CX3CL1) in serum. This decrease in IL-6 may promote microglial proliferation and survival as a modulatory effect response, while the increase in BDNF might suggest a regulatory mechanism in microglia–neuron interaction responses. However, tDCS did not enhance the cognitive or modulatory effects of CS, suggesting that longer interventions might be required to achieve substantial benefits.

Structural inequality, the uneven distribution of resources and opportunities, influences health outcomes. However, the biological embedding of structural inequality in aging and dementia, especially among underrepresented populations, is unclear. We examined the association between structural inequality (country-level and state-level Gini indices) and brain volume and connectivity in 2,135 healthy controls, and individuals with Alzheimer’s disease and frontotemporal lobe degeneration from Latin America and the United States. Greater structural inequality was linked to reduced brain volume and connectivity, with stronger effects in Latin America, especially in the temporo-cerebellar, fronto-thalamic and hippocampal regions. In the United States, milder effects were observed in the insular-cingular and temporal areas. Results were more pronounced in Alzheimer’s disease and were independent of age, sex, education, cognition and other confounding factors. The findings highlight the critical role of structural inequality in aging and dementia, emphasizing the biological embedding of macrosocial factors and the need for targeted interventions in underserved populations.

Brain clocks, which quantify discrepancies between brain age and chronological age, hold promise for understanding brain health and disease. However, the impact of diversity (including geographical, socioeconomic, sociodemographic, sex and neurodegeneration) on the brain-age gap is unknown. We analyzed datasets from 5,306 participants across 15 countries (7 Latin American and Caribbean countries (LAC) and 8 non-LAC countries). Based on higher-order interactions, we developed a brain-age gap deep learning architecture for functional magnetic resonance imaging (2,953) and electroencephalography (2,353). The datasets comprised healthy controls and individuals with mild cognitive impairment, Alzheimer disease and behavioral variant frontotemporal dementia. LAC models evidenced older brain ages (functional magnetic resonance imaging: mean directional error = 5.60, root mean square error (r.m.s.e.) = 11.91; electroencephalography: mean directional error = 5.34, r.m.s.e. = 9.82) associated with frontoposterior networks compared with non-LAC models. Structural socioeconomic inequality, pollution and health disparities were influential predictors of increased brain-age gaps, especially in LAC (R² = 0.37, F² = 0.59, r.m.s.e. = 6.9). An ascending brain-age gap from healthy controls to mild cognitive impairment to Alzheimer disease was found. In LAC, we observed larger brain-age gaps in females in control and Alzheimer disease groups compared with the respective males. The results were not explained by variations in signal quality, demographics or acquisition methods. These findings provide a quantitative framework capturing the diversity of accelerated brain aging.

Background: LatAm‐FINGERS is the first non‐pharmacological multicenter randomized clinical trial to prevent cognitive impairment in Latin America (LA). The trial congregates the effort of 12 Countries, including Argentina, Bolivia, Brazil, Chile, Colombia, Costa Rica, Dominican Republic, Ecuador, Mexico, Peru, Puerto Rico, and Uruguay. The main aim is to investigate the feasibility of a 24‐month multi‐domain lifestyle intervention and its efficacy on the cognition of 1200 participants.Method: Recruitment strategies differed across countries and regions because they were adapted to the idiosyncrasies of the local populations. Recruitment from medical center databases was found insufficient to provide a diverse cohort. Alternative strategies included social media posts with infographics and videos. A novel and successful strategy was in‐person talks in local city halls and local nongovernmental organizations for older adults. The use of positive colloquial language was found to be much more effective in reaching underserved populations than scientific language (e.g., focusing on brain health vs. clinical trials). A significant recruitment source in low‐income regions of Peru, Bolivia, and Ecuador was the promotion within non‐Catholic religious organizations. Appealing to the religious leaders’ endorsement was crucial for generating trust and interest in different communities. In Mexico, one successful recruitment strategy involved performing physical exercises in local parks in low‐income neighborhoods to demonstrate the intervention in‐vivo, which attracted interested people from the area. Overall, in‐person contact with participants and time dedicated to explaining the trial’s rationale in lay language was the most important strategy.Result: As of January 2023, we have enrolled 948 participants in the study. The mean (SD) age is 67.5 (4.8) years, 75% are female, the level of education is 12.6 (3.8) years, and the MMSE score is 27.3 (1.7). To date, 58% of the population self‐reports as mestizo (mixed race), and 28% as Caucasian. Other ethnicities represented include Native American (1.5%), Mulato (5%), Black (2%), Asian (0.7%), and other (5%).Conclusion: The LatAm‐FINGERS trial recruited participants from a wide range of diverse populations. Our results support that using tailored and idiosyncratic strategies is decisive in reaching different communities and ensuring the representativeness of the study sample.

Background: Older adult participation in lifestyle‐based programs has been described round 80%. (Lee et al., 2018). Participation at dementia prevention programs has been influenced by age, gender, marital status, and interest in receiving health education (Coley et al., 2021). The aim of this study is to evaluate the participation and adoption of lifestyle changes of older adults in a multidomain dementia prevention program from the LatAm Fingers Initiative, in MexicoMethod: healthy cognitive older adults between 60 to 77 years old were recruited. 148 pre‐screenings were done to complete a 100 participants sample, all of them were randomized between Systematic (SIG) (supervised participation) or Flexible FIG (educational advises) Lifestyle Intervention groups (50 per group). Participation is defined as attendance to educational session for physical, nutritional, cognitive and cardiovascular health plus attendance to physical activities, diary diet delivery, and 48 levels per week of cognitive online activities through 6‐months. Participation was classified as low, moderate, and high.Result: Mean age was 70.06 (±5.4) years old, and 70.8% participants were females. From 48 participants of the systematic group (SIG) there were two dropouts because problems for traveling, and work. 45% of the SIG, are participating on the four intervention domains. 40 participants are currently at the physical activity intervention. From them high participation and adoption of physical activity was 52.5%, moderate participation was 37.5% and low, 10%. From Nutritional intervention are 26 participants who showed high participation at 57.7%, 11.5% moderate and 30.8%, low. The 21 participants that are at the Cognitive intervention stage, 33.3% had high participation, 52.4% moderate and 14.3% low participation. From the 18 participants at the health intervention stage, 94.4% participants had high participation and 5.6% low.Conclusion: from this preliminary data, we found that the in the SIG the participation rates, are moderate to high. Physical, nutritional, and cardiovascular health activities showed more than 50% of participation rate. Also, nutritional domain showed the lowest percentage of participation among the four interventions.

Background: The proportion of older people have consequences for labor and financial market. Older adults (OA) can consume economic resources that they cannot afford, total health care spending is three times greater in households with at least one OA with a disability, 70% of the costs of caring for someone with dementia are borne by families and reported emotional and financial hardships are twice as high for caregivers of this OA. This study focuses on the impact of physical and cognitive disabilities on the economic difficulties of the families.Method: This was an observational, cross‐sectional study. It involved 2396 people aged 65 years and older, identified within the dementia research group protocols (DRG)10/66. Measures included the WHODAS 2.0 and the INDEP economic hardship study assessments. We performed descriptive statistics of the sociodemographic distribution and explored the association of physical disability, dementia, or both, with the presence of sociodemographic and economic variables with different types of supports for coping the “financial hardship” using bivariate tests and logistic regression models, odds ratios were estimated to assess the associations of interest.Result: The distribution of disability with or without cognitive impairment was greater in women and cognitive impairment was greater in men (p = 0.010). When analyzing the distribution of the types of economic support, resorting to social assistance programs showed an association with the presence of cognitive impairment with disability odds ratio (OR) of 10.4 (95% confidence interval = 95%CI 1.3‐81.1) and without disability OR 8.0 (95%CI 1.1‐59.7) in the adjusted estimators (RR). Recourse to the work setting support was associated with the presence of disability in simple RR, OR 2.2(95%CI 1.2‐4.2) and adjusted OR 2.5(95%CI 1.3‐4.8). Support from friends or relatives was associated with the presence of disability and cognitive impairment also in simple RR OR 2.0 (95%CI 1.4‐3.0) and adjusted OR 2.1(95%CI 1.4‐3.3).Conclusion: In older Mexican adults, cognitive impairment increases the use of social assistance programs, physical disability increases the use of savings or property, and the presence of cognitive impairment with physical disability increases the use of social assistance programs, support in the work setting and from friends or family.

Background: Computerized training has been used to improve cognitive functioning and has been shown to be effective in a wide range of populations. However, its use in elders can be complicated due to many factors including schooling, motivation, perception of difficulty and unfamiliarity with the technology. For the multidomain dementia prevention program LatAm‐FINGERS, the brainHQ software is being used to perform the cognitive training. The aim of this work is to show the perception of participants about this program.Method: Twenty‐five urban‐Mexican elders cognitively healthy but with risk factors for dementia, are receiving the cognitive training through brainHQ. They indicated in a 5‐point Likert scale (1 = low, 5 = high) how enthusiastic and fearful they felt to begin the training and how difficult it has been. They also reported if they used a smartphone, a computer or a tablet before and how comfortable they felt using it.Results: Participants were between 60‐77 years old, with an average age of 70.9 ± 4.7 years old and an average schooling of 9.33 ± 3.5 years, 56% were females. Most of the sample (92%) uses smart technology, mainly smartphones, but only 8% feels very comfortable using it, 55% reports regular comfort and 37% feels not comfortable at all. When asked about brainHQ training, over half of the sample (56%) reported high enthusiasm, 68% reported little fear and more than half reported some degree of difficulty (see figure 1). No significant differences between men and women were found. Using Spearman`s test, a significant negative correlation between schooling and perceived difficulty was found (rho = ‐.68, p = .03), but not between schooling and enthusiasm or fear.Conclusion: In general, the participants have a good attitude towards the use of brainHQ, although they reported not feeling very comfortable with the use of intelligent technologies, they were enthusiastic about starting the training, and most of them were not afraid. However, the perceived difficulty could hinder training, especially in those with less schooling, therefore, it is important to develop strategies that encourage them to continue with the program to obtain the benefits of computerized training.