ABSTRACT
BACKGROUND: Education influences brain health and dementia. However, its impact across regions, specifically Latin America (LA) and the United States (US), is unknown. METHODS: A total of 1412 participants comprising controls, patients with Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD) from LA and the US were included. We studied the association of education with brain volume and functional connectivity while controlling for imaging quality and variability, age, sex, total intracranial volume (TIV), and recording type. RESULTS: Education influenced brain measures, explaining 24%-98% of the geographical differences. The educational disparities between LA and the US were associated with gray matter volume and connectivity variations, especially in LA and AD patients. Education emerged as a critical factor in classifying aging and dementia across regions. DISCUSSION: The results underscore the impact of education on brain structure and function in LA, highlighting the importance of incorporating educational factors into diagnosing, care, and prevention, and emphasizing the need for global diversity in research. HIGHLIGHTS: Lower education was linked to reduced brain volume and connectivity in healthy controls (HCs), Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD). Latin American cohorts have lower educational levels compared to the those in the United States. Educational disparities majorly drive brain health differences between regions. Educational differences were significant in both conditions, but more in AD than FTLD. Education stands as a critical factor in classifying aging and dementia across regions.
ABSTRACT
Brain clocks, which quantify discrepancies between brain age and chronological age, hold promise for understanding brain health and disease. However, the impact of multimodal diversity (geographical, socioeconomic, sociodemographic, sex, neurodegeneration) on the brain age gap (BAG) is unknown. Here, we analyzed datasets from 5,306 participants across 15 countries (7 Latin American countries -LAC, 8 non-LAC). Based on higher-order interactions in brain signals, we developed a BAG deep learning architecture for functional magnetic resonance imaging (fMRI=2,953) and electroencephalography (EEG=2,353). The datasets comprised healthy controls, and individuals with mild cognitive impairment, Alzheimer's disease, and behavioral variant frontotemporal dementia. LAC models evidenced older brain ages (fMRI: MDE=5.60, RMSE=11.91; EEG: MDE=5.34, RMSE=9.82) compared to non-LAC, associated with frontoposterior networks. Structural socioeconomic inequality and other disparity-related factors (pollution, health disparities) were influential predictors of increased brain age gaps, especially in LAC (R2=0.37, F2=0.59, RMSE=6.9). A gradient of increasing BAG from controls to mild cognitive impairment to Alzheimer's disease was found. In LAC, we observed larger BAGs in females in control and Alzheimer's disease groups compared to respective males. Results were not explained by variations in signal quality, demographics, or acquisition methods. Findings provide a quantitative framework capturing the multimodal diversity of accelerated brain aging.
ABSTRACT
Cognitive studies on Parkinson's disease (PD) reveal abnormal semantic processing. Most research, however, fails to indicate which conceptual properties are most affected and capture patients' neurocognitive profiles. Here, we asked persons with PD, healthy controls, and individuals with behavioral variant frontotemporal dementia (bvFTD, as a disease control group) to read concepts (e.g., 'sun') and list their features (e.g., hot). Responses were analyzed in terms of ten word properties (including concreteness, imageability, and semantic variability), used for group-level comparisons, subject-level classification, and brain-behavior correlations. PD (but not bvFTD) patients produced more concrete and imageable words than controls, both patterns being associated with overall cognitive status. PD and bvFTD patients showed reduced semantic variability, an anomaly which predicted semantic inhibition outcomes. Word-property patterns robustly classified PD (but not bvFTD) patients and correlated with disease-specific hypoconnectivity along the sensorimotor and salience networks. Fine-grained semantic assessments, then, can reveal distinct neurocognitive signatures of PD.
ABSTRACT
Introducción: la patología vascular cerebral tiene un enormeimpacto en la vida de las personas. Ocasiona grandes pérdidasdesde el punto de vista físico, psicológico y social. La recuperaciónde la enfermedad cerebrovascular aguda (ECVA) esun fenómeno complejo que hasta la fecha ha sido escasamenteinvestigado desde la perspectiva del paciente. El objetivo deeste trabajo es conocer qué significa la recuperación para laspersonas que recientemente han sufrido un ictus.Metodología: estudio cualitativo en el que se desarrollaronentrevistas en profundidad a 12 pacientes afectados de ictus duranteel primer mes de su recuperación. Se entrevistó en dosocasiones a cada participante, una en el hospital y otra en sudomicilio. Las entrevistas fueron grabadas y transcritas en sutotalidad. Se alcanzó la saturación de los datos. El texto generadofue analizado mediante análisis del discurso.Resultados y conclusiones: el significado de la recuperaciónpara los pacientes es un objetivo, en el que la pérdida y la recuperaciónde lo perdido son lo importante, y un proceso dondela esperanza, la incertidumbre y la búsqueda de evidenciasde mejoría conforman las categorías. Describieron que paraellos recuperarse significa llegar a estar como estaban antesdel ictus o en el caso de que esto no fuera posible, por lo menos,recuperar para valerse. A pesar de que reconocen que sufuturo es incierto, conservan la esperanza de que con tiempoy esfuerzo conseguirán recuperarse.Los resultados obtenidos son coherentes con la bibliografíarevisada. La comprensión de lo que recuperarse significa paralas personas con ictus es esencial para el planteamiento de objetivosy el desarrollo de planes de cuidados individualizados (AU)
Introduction: Brain vascular pathology has an enormous impacton the patients life. It leads to great physical, psychologicaland social losses. Recovery from acute cerebrovasculardisease (ACVD) is a complex phenomenon which up untilrecently had been scarcely studied from the patients perspective.The objective of this study is to understand what recoverymeans to patients who have recently suffered an ictus.Methodology: qualitative study in which 12 ictus patientswere interviewed in-depth within the first month of recovery.Each participant was interviewed twice, once in the hospitaland once in their home. Each interview was recorded andtranscribed in its entirety. Data saturation was reached. Thegenerated text was analyzed using discourse analysis.Results and conclusions: to patients, recovery encompassestwo dimensions: recovery as an objective, in which loss andrecovery of what has been lost are the most important aspects;and recovery as a process, where hope, uncertainty and thesearch for evidence of improvement constitute the categories.They determined that recovery means returning to their previousstate, before the ictus, or, in the case of that not beingpossible, at least recovering enough to be self-sufficient.Although they acknowledge that their future is uncertain, theyremain hopeful that with time and effort they will achieve recovery.The results obtained are coherent with reviewed literature.Understanding what recovery means to ictus patients is essentialto determine objectives and to develop individualizad care plans (AU)