Objectives: Leveraging the non-monolithic structure of Latin America, which represents a large variability in social determinants of health (SDoH) and high levels of genetic admixture, we aim to evaluate the relative contributions of SDoH and genetic ancestry in predicting dementia risk in Latin American populations

Methods: Community-dwelling participants aged 65 and older (N = 3808) from Cuba, Dominican Republic, Mexico, and Peru completed the 10/66 protocol assessments. Dementia was diagnosed using the cross-culturally validated 10/66 algorithm. The primary outcome measured was the risk of developing dementia. Multivariate linear regression models adjusted for SDoH were used in the main analysis.

Results: We observed extensive three-way (African/European/Native American) genetic ancestry variation between countries. Individuals with higher proportions of Native American (>70%) and African American (>70%) ancestry were more likely to exhibit factors contributing to worse SDoH, such as lower educational levels (p <0.001), lower SES (p < 0.001), and higher frequency of vascular risk factors (p < 0.001). In unadjusted analysis, American individuals with predominant African ancestry exhibited a higher dementia frequency (p = 0.03) and both Native and African ancestry predominant groups showed lower cognitive performance relative to those with higher European ancestry (p < 0.001). However, after adjusting for measures of SDoH, there was no association between ancestry proportion and dementia probability, and ancestry proportions no longer significantly accounted for the variance in cognitive performance (African predominant p = 0.31 [–0.19, 0.59] and Native predominant p = 0.74 [–0.24, 0.33]).

Conclusions: The findings suggest that social and environmental factors play a more crucial role than genetic ancestry in predicting dementia risk in Latin American populations. This underscores the need for public health strategies and policies that address these social determinants to reduce dementia risk in these communities effectively.

Objectives: Population ageing will lead to a dramatic increase in dementia prevalence globally. Recent evidence suggests a decline in dementia incidence in HIC due to increasing education levels and improvements in cardiovascular health. Although, most of the increase will occur in low and middle-income countries (LMICs), there are no recent estimates of dementia prevalence and incidence in LMICs. The present study aimed to examine new trends on dementia prevalence and incidence in Latin-America and associations of socioeconomic determinants and cardiovascular risk factors.

Methods: Sample size included older adults from Latin America (Cuba, Dominican Republic [DR], Puerto Rico [PR], and Mexico) drawn from the 10/66 Dementia Research Group study. We compare wave 1 (2003–2006) with wave 3 (2016 – 2019) of 10/66 studies. The main outcome was dementia prevalence relative to previous waves. Dementia diagnosis was determined according to the 10/66 dementia criteria. All the 10/66 waves used the same standardized assessments and protocols.

Results: Comparing the first wave (2003 - 2006) with the third wave (2016 - 2019) in four Latin American countries – Cuba, the Dominican Republic, Mexico, and Peru – reveals significant trends in dementia prevalence. Preliminary data suggest an increase in the Dominican Republic, Mexico, and Peru, while Cuba slightly declined, from 12.4 percent in Wave 1 to 10.1 percent in Wave 3. In contrast, the Dominican Republic’s age-adjusted prevalence rose from 11.5 percent to 13.6 percent, Peru from 9.2 percent to 16.8 percent, and Mexico from 8.3 percent to 17.1 percent. Despite, improvements in levels of education, increases in dementia prevalence were associated with higher rates of cardiovascular disease and cardiovascular risk factors, including diabetes, hypertension, obesity and heart disease in the later-born cohorts. Self-reported stroke is also rising.

Conclusions: The increasing prevalence of dementia in LAC underscores the urgent need for targeted health interventions. Prevention strategies should emerge as a key focus in the battle against dementia in Latin America. Addressing modifiable risk factors can significantly impact the incidence and prevalence ofdementia.

Objectives: Because of the continued transition to older populations, various strategies have been developed to estimate the social impact and burden of health care. Regarding mental health, a strategy in the elderly is the measurement of neuropsychiatric symptoms (NPS), these include a wide range of behavioral and psychological manifestations. These are more frequent in the presence of some diseases, such as neurodegenerative syndromes, among which dementias and Parkinson’s disease (PD) stand out. The present study seeks to analyze the frequency of NPS, its relationship with the presence or absence of neurodegenerative syndromes and some characteristics of the elderly and caregivers.

Methods: This is an analysis of data from 12,865 elderly people evaluated within the protocols of the Dementia Research Group 10/66 in 6 Latin American countries (Cuba, Dominican Republic, Puerto Rico, Mexico, Venezuela and Peru). The presence or absence of parkinsonism, dementia and parkinsonism plus dementia (PDD) was identified through previously validated and published Methods. The NPS were assessed using the 12-symptom questionnaire version of the Neuropsychiatric Inventory. Other characteristics such as age, sex and education, in patients and caregivers; socioeconomic status, disability and comorbidities in the elderly; relationship with the elderly, needs and care-burden were assessed in careers.

Results: The most frequent symptoms were depression and sleep disorders in the four groups (without non-NDS neurodegenerative syndromes, parkinsonism, dementia and PDD, ranging from 23% to 49%. About a third of the elderly with parkinsonism, half of those with dementia, and 3 out of 5 of the elderly with PDD had 3 or more NPS. The odds ratios (OR) of each NPS measure by multivariate logistic regression models shown OR from 1.4 to 1.9 in the presence of parkinsonism; between 1.7 and 9.3 in the presence of dementia; and between 1.9 and 10.2 in the presence of PDD.

Conclusions: From a clinical and public mental health perspective, it is necessary to implement systematic Methods for NPS screening, as well as develop support strategies for families and caregivers, mainly of those with neurodegenerative syndromes.

Objectives: Dementia presents a growing public health challenge globally and its impact is significantly pronounced in low and middle-income countries (LMICs), including those in Latin America. This symposium aims to present recent findings on the prevalence, impact, and underlying factors of cognitive impairment and neuropsychiatric symptoms in aging populations across Latin America, with a focus on culturally and regionally specific research findings.

Methods: The symposium will consolidate data from the 10/66 Dementia Research Group, which has conducted extensive research across various Latin American countries. We integrate results from multiple investigations with over 12,000 elderly participants from six Latin American countries, utilizing cross-sectional and longitudinal Methodsologies. These studies employ the 10/66 Dementia Research Group protocols, among other internationally recognized diagnostic tools, to assess dementia, neurodegeneration and neuropsychiatric symptoms.

Results: The symposium will delve into critical yet not well-understood topics. The audience will be first introduced to emerging trends of dementia prevalence and incidence in Latin America and the interaction with different risk factors particular to the region. Second, we will discuss findings from a comprehensive analysis focusing on the prevalence and impact of cognitive impairment and incident dementia in parkinsonism and Parkinson’s Disease. The third presentation will focus on the prevalence of neuropsychiatric symptoms across cognitively unimpaired, dementia, and Parkinson’s’ disease, emphasizing the need to implement systematic screening Methods for early detection from a clinical and public health perspective. The final talk will present data exploring the influence of genetic ancestry alongside social and environmental factors as predictors of dementia risk in Latin America.

Conclusions: The findings presented underscore the complex interplay of genetic, social, and environmental factors in the etiology and progression of neurodegenerative and neuropsychiatric conditions in Latin America. The symposium will highlight the critical need for comprehensive public health strategies and enhanced research focus to better understand and address these issues within aging populations.

Triatomines (Hemiptera: Heteroptera: Reduviidae) are hematophagous insects, well-known for their vectorial role in transmitting Trypanosoma cruzi Chagas (Kinetoplastida: Trypanosomatidae) parasites, the etiological agent of Chagas disease. Trapping these insects would limit human-triatomine interaction and, thus, control the disease. In this context, there is a critical need for effective lures to control triatomines. Through double-choice bioassays, we investigated the preference of Triatoma infestans Klug, T. pallidipennis Stal, and Rhodnius prolixus Stal triatomines for: (a) volatiles from fermented products (various fermentation types and substrates) and (b) commercial insect lures. Furthermore, we identified the chemical composition of these volatiles through headspace collection using Solid Phase Micro Extraction coupled with Gas Chromatograph-Mass Spectrometer (HS-SPME-GC-MS). Volatiles from lactic fermentation and certain fermented fruits, along with commercial lures, attracted triatomines, while other products exhibited possible repellent or dislodging properties. These findings hold promise for the control of triatomines and, ultimately, Chagas disease.

Opus signinum is a lime mortar mix that includes crushed pottery as an aggregate. Because it is water-resistant, it was used to line hydraulic structures like pools and aqueducts. While there have been numerous recreations of Roman ‘concretes’ in the past, hydrophobic linings have received little attention, and all preliminary studies in these recreations have paid more attention to the dry components and the lime than to the hydric needs of the mortar. The experiment presented here was to gain a better understanding, with the help of traditional builders, of the process of mixing and applying hydrophobic linings and calculate the water consumption of individual samples. The data obtained contribute to assessing the water consumption needs on Roman construction sites, what associated logistics these volumes required, and what the technicalities of applying this specific type of lining were.

Rhipicephalus microplus, the cattle fever tick, is the most important ectoparasite impacting the livestock industry worldwide. Overreliance on chemical treatments for tick control has led to the emergence of acaricide-resistant ticks and environmental contamination. An immunological strategy based on vaccines offers an alternative approach to tick control. To develop novel tick vaccines, it is crucial to identify and evaluate antigens capable of generating protection in cattle. Chitinases are enzymes that degrade older chitin at the time of moulting, therefore allowing interstadial metamorphosis. In this study, 1 R. microplus chitinase was identified and its capacity to reduce fitness in ticks fed on immunized cattle was evaluated. First, the predicted amino acid sequence was determined in 4 isolates and their similarity was analysed by bioinformatics. Four peptides containing predicted B-cell epitopes were designed. The immunogenicity of each peptide was assessed by inoculating 2 cattle, 4 times at 21 days intervals, and the antibody response was verified by indirect ELISA. A challenge experiment was conducted with those peptides that were immunogenic. The chitinase gene was successfully amplified and sequenced, enabling comparison with reference strains. Notably, a 99.32% identity and 99.84% similarity were ascertained among the sequences. Furthermore, native protein recognition was demonstrated through western blot assays. Chitinase peptide 3 reduced the weight and oviposition of engorged ticks, as well as larvae viability, exhibiting a 71% efficacy. Therefore, chitinase 3 emerges as a viable vaccine candidate, holding promise for its integration into a multiantigenic vaccine against R. microplus.

The objective of this study was to determine the effect of dietary calcium soaps from garlic (Allium sativum) and willow (Salix babylonica) extracts on nematode loads, nutrient intake and digestibility, nitrogen balance and rumen fermentation kinetics in dairy goats. Nine adult non-lactating Saanen goats were grouped into a complete randomized block design with 3 treatments (n = 3) over a period of 28 d. Animals were fed a diet based on alfalfa hay and a concentrate that was supplemented (65 g/kg DM) with calcium soaps of safflower (control), garlic or willow. Intake of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) were not affected by dietary calcium soaps. However, the highest digestibility of DM and OM were observed in willow supplemented goats. In vitro gas kinetics and fermentation profile were not affected by diets. Results from fecal egg count indicated a reduction in total count, Haemonchus spp. and Trychostrongylus spp. for both garlic and willow compared to control. Our results suggest that calcium soaps of garlic or willow extracts can be used to reduce gastrointestinal parasites in goats without compromising productive traits or rumen function.

Naturally deformed biotite in contact-metamorphosed slates affected by a shear zone of the Southern Iberian Massif near Jaén (SE Spain) were studied by X-ray diffraction, optical microscopy, scanning electron microscopy, electron probe microanalysis and high-resolution transmission and analytical electron microscopy. Biotite is found in the contact metamorphism aureole produced by the intrusion of a granodioritic stock, but shear strain caused its deformation. The southern part of the shear band is strongly deformed, containing thick clay gouge zones. The northern part is less deformed and develops weaker planar-linear fabrics. X-ray diffraction data reveal the predominance of the 2M1 biotite in the undeformed samples whereas the 1M polytype is predominant in the sheared samples. Chemical data and electron images of the biotite from unsheared slates do not show the presence of intercalated phases. This biotite is almost defect-free and electron diffraction patterns have sharp reflections indicating a two-layer polytype (probably 2M1). Back-scattered electron images from the deformed biotite in the moderate deformation part of the shear zone do not reveal intergrown minerals, but the electron microprobe analyses show some Fe- and Mg-enriched compositions. Transmission electron microscopy indicates that disordered polytype packets are predominant (probably 1Md). Their electron diffraction patterns have diffuse streaking along c*. These packets have high dislocation densities, microcavities with ∼5 Å latticefringe regions (probably brucite-like sheets) and interlayering of chlorite-berthierine. Kaolinized biotite can be observed in the clay gouges from the strongly deformed south part of the shear zone. The degree of streaking, as an indication of the intensity of deformation, revealed that the disordered polytype packets are more deformed than the two-layer polytype packets. The microcavities of the disordered polytype packets could act as potential channels for transport of fluids during the shearing stage and serve as sites for chloritization of biotite, producing chlorite-berthierine domains within biotite. Berthierine is an intermediate metastable phase replaced by chlorite with along-layer transitions.

The effects of a subvolcanic intrusion on its host rocks in the Priego de Córdoba area (SE Spain) was studied by optical microscopy, X-ray diffraction and electron microscopy. The intrusion of a laccolith of stratiform dolerite in partially consolidated marly sediments at quite shallow depths below the ocean floor took place during the intracontinental rifting phase of the Subbetic zone of the Betic Cordilleras. In the first stage, contact metamorphism caused the crystallization of calc-silicate consisting of grossular andradite garnet, diopside, vesuvianite and titanite for which the upper temperature limit was 500°C. Phyllosilicates are found in a network of veins cross-cutting the carbonate and calc-silicate matrix, indicating their formation during a process of hydrothermal alteration superimposed on the contact aureole. In the area closest to the subvolcanic rocks, saponite is the main phyllosilicate although some dispersed chlorite is found. In the zone furthest from the contact, corrensite together with saponite and beidellitic smectites were observed. The presence of low-temperature phases (saponite) in the area closest to the laccolith reveals the evolution of the hydrothermal system toward cooler conditions. In the early stage, the circulation of a hot hydrothermal fluid caused the crystallization of chlorite in the area surrounding the subvolcanic body and corrensite in the more distal area, which might have begun even during the contact metamorphism stage. A cooling phase followed, resulting in the crystallization of saponite in the host rocks, and the crystallization of dioctahedral and trioctahedral smectites inside the subvolcanic body.

El objetivo de este artículo es establecer el nivel de eficiencia del gasto público sanitario en América Latina y comprobar su relación con determinadas características institucionales como calidad regulatoria, participación del sector privado, descentralización o tamaño de la burocracia. Se estima una frontera estocástica de verdaderos efectos aleatorios que relaciona el gasto público en salud per cápita frente a la tasa de mortalidad neonatal e infantil y la esperanza de vida después de los sesenta años. Se regresan las ineficiencias resultantes respecto del conjunto de variables institucionales explicativas. Se evidencia el importante papel del gasto público sanitario en la obtención de determinados niveles de realización sanitaria. Sin embargo, su eficiencia es mejorable, especialmente a partir de optimizar la calidad regulatoria del Estado. Latinoamérica ha configurados sistemas sanitarios complejos, pero no han logrado mejorar la coordinación entre sus actores, lo que explica su ineficiencia. La rectoría del gobierno es esencial.

The effects of the farming system (conventional-organic-abandoned) and soil management (native cover crop vs tillage) on vascular plant species were analyzed in sloping olive groves (>20%) in 20 different locations in Andalusia, SE Spain. The soil management techniques included Organic Tillage (OT), Organic Cover Crops (OC), Conventional Tillage (CT), Conventional Non-Tillage (CNT), Abandoned Cover Crops (AC) and Abandoned Woody (AW). Data for the vascular plant species were recorded through three line transects of 30 m with a bar perpendicularly touching every 1 m of the measuring tape. Environmental variables were also recorded at plot level to assess their influence. Dependent variables, such as species abundance, richness and diversity indexes were studied using univariate analysis (one-way ANOVA, Kruskal–Wallis test) while multivariate statistics (ANOSIM, SIMPER, DCA) were used for analyzing the data matrices. We found that the different combinations of farming system and soil management affect biological diversity in terms of individual abundance, plant cover, species richness and diversity, species and family composition. Life forms and species distribution patterns are also affected. The main environmental variables affecting the plant taxa were those related with soil and climate characteristics, slope, olive age and intensive land uses at landscape level, including the percentage of artificial surfaces. The lowest levels of biodiversity (e.g., species richness) were found in the tilled olive groves (CT = 8.1 sp. ± 2.2, OT = 10.0 sp. ± 5.4). Surprisingly, the organic tilled groves (OT) were very poor in species compared to those with native plant cover (OC = 27.9 sp. ± 3.0). The latter, however, showed similar species richness to the abandoned olive groves (AC = 21.2 sp. ± 3.7, AW = 27.2 sp. ± 3.0). Possible solutions for increasingly uncompetitive sloping olive groves include conversion to organic with native plant cover or abandonment for rewilding.

En las fronteras indígenas del Río de la Plata y Chile meridional, principalmente en la primera, la comunicación interétnica estuvo condicionada para las autoridades coloniales por una endémica escasez de lenguaraces e intérpretes, de quienes dependían debido a su habitual desconocimiento del mapu dungum, lengua del sur del reino de generalizada utilización en el siglo XVIII por todos los grupos nativos de la región. Con relación a estos últimos, en cambio, no son pocos los casos documentados de personas que habían incorporado el habla de Castilla (o español como se la denominaba) y la utilizaban en actividades de mediación —inclusive por circunstancial requerimiento de la administración— y de inteligencia. En este artículo, se examinan las distintas maneras en que los oficiales reales, los sacerdotes y especialmente los hombres y mujeres indígenas enfrentaron y resolvieron las dificultades inherentes a la adquisición de ambas lenguas y a las demandas de intermediación.

This study aimed to assess the impact of the introduction of pneumococcal conjugate vaccine 13 (PCV13) on the molecular epidemiology of invasive pneumococcal disease (IPD) in children from Andalusia. A population-based prospective surveillance study was conducted on IPD in children aged <14 years from Andalusia (2018–2020). Pneumococcal invasive isolates collected between 2006 and 2009 in the two largest tertiary hospitals in Andalusia were used as pre-PCV13 controls for comparison of serotype/genotype distribution. Overall IPD incidence rate was 3.55 cases per 100 000 in 2018; increased non-significantly to 4.20 cases per 100 000 in 2019 and declined in 2020 to 1.69 cases per 100 000 (incidence rate ratio 2020 vs. 2019: 0.40, 95% confidence interval (CI) 0.20–0.89, P = 0.01). Proportion of IPD cases due to PCV13 serotypes in 2018–2020 was 28% (P = 0.0001 for comparison with 2006–2009). Serotypes 24F (15%) and 11A (8.3%) were the most frequently identified non-PCV13 serotypes (NVT) in 2018–2020. Penicillin- and/or ampicillin-resistant clones mostly belonged to clonal complex 156 (serotype 14-ST156 and ST2944 and serotype 11A-ST6521). The proportion of IPD cases caused by PCV13 serotypes declined significantly after the initiation of the PCV13 vaccination programme in 2016. Certain NVT, such as serotypes 24F and 11A, warrant future monitoring in IPD owing to invasive potential and/or antibiotic resistance rates.

Alzheimer’s disease (AD) and dementia has emerged as a significant societal issue and a global priority. The prevalence of dementia is rising more rapidly in low and middle income countries (LMIC) than in high income countries. A growing body of evidence shows that prevention through risk factor management is the key to reducing the burden of dementia in the society, especially in LMIC. However, a one-size-fits all approach to health promotion is neither efficient nor effective. Latin American countries (LAC) have unique challenges related to dementia, including rapid aging population, high admixture degree and risk factors profile, which influence the prevalence and presentation of dementia. During this session, we will present findings and tools that will help tailor and personalize risk factor management in Hispanics populations. Participants will be first introduced to genetics of Alzheimer disease in Hispanic populations relative to non-Hispanics and the influence of gene by environment interactions. The second presentation will report on the epidemiology and risk factors of AD using cross countries/society comparisons (Non-Hispanics whites vs Hispanics living in US vs Hispanics living in Latin America.) The third presenter will discuss the development of a tool that visualizes how each risk factor contributes to the risk of dementia and how one may lower their risk by addressing the risk factors. The tool can be used in primary care settings in Cuba, Dominican Republic and Puerto Rico. Finally, the fourth presenter uses state-of-the-art digital assessment tools (brain health assessment), for low-cost monitoring of cognitive functioning, MCI and dementia. Such instruments are important for future evaluation of the impact of preventive strategies. At the end of the presentations, attendees will be able to identify the unique genetic and social determinants that drive AD in LAC. Recommendations will be given for preventive strategies tailored to LMIC. The findings to be shared will be essential for building evidence-based interventions tailored to reducing the burden of dementia in the Hispanic populations.

Session Chair:

Juan Llibre Rodriguez

Alzheimer Disease and genetics in Hispanic Populations

Jorge J Llibre-Guerra

Alzheimer disease epidemiology and risk factors in Caribbean and non-Caribbean Hispanics populations.

Ivonne Z. Jiménez Velázquez

Development of a tool to motivate for healthy behaviors to prevent dementia in the Caribbean.

Daisy Acosta

A brief digital cognitive assessment for detection of cognitive impairment in Hispanics populations.

Ana Rodriguez-Salgado

The main objective of this study was to examine the effectiveness of an intervention implemented by elementary school teachers within the context of the Response to Intervention (RtI) model. For this purpose, a Tier 2 or secondary intervention was implemented by Spanish-speaking teachers in grades K-3 after receiving training to implement RtI components with fidelity. A total of 1,923 at-risk students were assigned to treatment (in reading, n = 542; in math, n = 483) or control (in reading, n = 406; in math, n = 492). Teachers were provided with a support system that included two web-based training programs for reading (i.e., Letra program) and math (i.e., Primate program). Implementation fidelity was analyzed using direct observations and self-reports. All students were assessed three times during the academic year. A hierarchical linear growth modeling was conducted, and differences in the growth rate of reading and math performance were analyzed between at-risk students who have received the intervention and those who have not received it. Children at-risk in the intervention condition appeared to benefit more than at-risk children in the control condition. Moreover, findings indicate that the earlier the intervention, the greater the percentage of students who leave the situation of risk of learning difficulties in reading and math.