Memory complaint in a middle-income country: a four-year longitudinal study in a cohort with low-education.

BACKGROUND: Memory complaints are frequent in older adults and are associated with higher risk of cognitive decline. OBJECTIVE: To investigate the functional outcome of individuals with memory complaints followed up at primary care centers. METHODS: Data were collected between 2016 e 2020 in primary health care centers in Brazil. Patients underwent the Brief Cognitive Screening Battery, and the Functional Activities Questionnaire. RESULTS: The initial sample (2016) comprised 91 individuals classified into those with subjective cognitive decline (SCD, n = 15), mild cognitive impairment (MCI, n = 45), or dementia (n = 31). During follow-up, 8 individuals (8.8% of the initial sample) died and 26 (28.5% of the initial sample) were not found. Fifty-seven participants underwent clinical reassessment. Of 15 individuals with SCD, 7 were not found (46.7%), 4 (26.7%) progressed to MCI, and 4 (26.7%) remained stable. Of 45 individuals with MCI, 11 were not found (24.4%), 2 (4.4%) died, 6 (13.4%) progressed to dementia, 12 (26.7%) regressed to SCD, and 14 (31.1%) remained stable. Of 31 individuals with dementia, 8 were not found (25.8%), 6 (19.4%) died, 2 (6.5%) regressed to SCD, 7 (22.6%) regressed to MCI, and 8 remained stable (25.8%). Clinical improvement was due to the treatment of reversible causes, such as B12 hypovitaminosis and mood disorders. Older age, lower Mini-Mental State Examination, and higher scores of memory complaint, but not the use of benzodiazepines and of proton pump inhibitors, were predictors of functional status. CONCLUSION: Despite their limits (short sample size, missing data), these results support the idea that adequate screening, follow-up, and treatment of reversible causes of dementia in primary care are essential.

ANTECEDENTES: Queixas de memória são frequentes em idosos e estão associadas ao maior risco de declínio cognitivo. OBJETIVO: Investigar o desfecho funcional de indivíduos com queixas de memória acompanhados em centros atenção primária. MéTODOS: Os dados foram coletados entre 2016 e 2020 em centros de atenção primária à saúde no Brasil. Os pacientes foram submetidos à Bateria Cognitiva Breve e ao Questionário de Atividades Funcionais. RESULTADOS: A amostra inicial (2016) foi composta por 91 indivíduos, classificados como tendo declínio cognitivo subjetivo (DCS, n = 15), comprometimento cognitivo leve (CCL, n = 45), ou demência (n = 31). Durante o seguimento, 8 indivíduos (8,8% da amostra inicial) faleceram e 26 (28,5% da amostra inicial) não foram encontrados. Cinquenta e sete participantes foram submetidos à reavaliação clínica. Dos 15 indivíduos com DCS, 7 não foram encontrados (46,7%), 4 (26,7%) declinaram para CCL e 4 (26,7%) permaneceram estáveis. Dos 45 indivíduos com CCL, 11 não foram encontrados (24,4%), 2 (4,4%) morreram, 6 (13,4%) declinaram para demência, 12 (26,7%) evoluíram para DCS e 14 (31,1%) permaneceram estáveis. Dos 31 indivíduos com demência, 8 não foram encontrados, (25,8%), 6 (19,4%) morreram, 2 (6,5%) evoluíram para DCS e 7 (22,6%) para CCL; e 8 permaneceram estáveis (25,8%). A melhora clínica deveu-se ao tratamento de causas reversíveis, como hipovitaminose B12 e transtornos de humor. A idade avançada, a baixa pontuação no Mini-Exame do Estado Mental e os escores de queixa de memória mais altos, mas não o uso de benzodiazepínicos e inibidores da bomba de prótons, foram preditores de declínio funcional. CONCLUSãO: Apesar de suas limitações (amostra pequena, dados ausentes), esses resultados corroboram que a triagem adequada, o acompanhamento e o tratamento de causas reversíveis de demência na atenção primária são essenciais.

Impact of the Pandemic Time on the Mental Health of People with Dementia and Their Family Caregivers in Brazil and Chile: One-Year Follow-Up.

Background: Previous studies reported the negative impact of social isolation on mental health in people with dementia (PwD) and their caregivers, butlongitudinal studies seem scarcer. Objective: To describe a one-year follow-up impact of the COVID-19 pandemic on PwD and their caregivers in both Brazil and Chile. Methods: This study analyzed the impact of the pandemic on the psychological and physical health of PwD and their family caregivers after one year of follow-up in three outpatient clinics in Brazil (n = 68) and Chile (n = 61). Results: In both countries, PwD reduced their functional capacity after one year of follow-up (p = 0.017 and p = 0.009; respectively) and caregivers reported worse physical and mental health (p = 0.028 and p = 0.039). Only in Chile, caregivers reported more sadness associated with care (p = 0.001), and reduced time sleeping (p = 0.07). Conclusions: In conclusion, the COVID-19 pandemic appears to have had a long-lasting impact on PwD and their caregivers. However, it is essential to acknowledge that the inherent progression of dementia itself may also influence changes observed over a year.

Association of Alcohol Consumption with Cognition and Functionality in Older Adults Aged 75+ Years: The Pietà Study.

The relationship between alcohol consumption and cognition is still controversial. This is a cross-sectional population-based study conducted in Caeté (MG), Brazil, where 602 individuals aged 75+ years, 63.6% female, and with a mean education of 2.68 years, were submitted to thorough clinical assessments and categorized according to the number of alcoholic beverages consumed weekly. The prevalence rates of previous and current alcohol consumption were 34.6% and 12.3%, respectively. No association emerged between cognitive diagnoses and current/previous alcohol consumption categories. Considering current alcohol intake as a dichotomous variable, the absence of alcohol consumption was associated with dementia (OR = 2.34; 95%CI: 1.39-3.90) and worse functionality (p = 0.001). Previous consumption of cachaça (sugar cane liquor) increased the risk of dementia by 2.52 (95%CI: 1.25-5.04). The association between the consumption of cachaça and dementia diagnosis has not been described before.

Promoting diverse perspectives: Addressing health disparities related to Alzheimer's and all dementias.

Dementia research lacks appropriate representation of diverse groups who often face substantial adversity and greater risk of dementia. Current research participants are primarily well-resourced, non-Hispanic White, cisgender adults who live close to academic medical centers where much of the research is based. Consequently, the field faces a knowledge gap about Alzheimer's-related risk factors in those other groups. The Alzheimer's Association hosted a virtual conference on June 14-16, 2021, supported in part by the National Institute on Aging (R13 AG072859-01), focused on health disparities. The conference was held entirely online and consisted of 2 days of core programming and a day of focused meetings centered on American Indian and Alaska Natives and on LGBTQIA+ populations. Over 1300 registrants attended discussions focused on the structural and systemic inequities experienced across diverse groups, as well as ways to investigate and address these inequities.

miRNAs in cerebrospinal fluid associated with Alzheimer's disease: A systematic review and pathway analysis using a data mining and machine learning approach.

Alzheimer's disease (AD) is the most common type and accounts for 60%-70% of the reported cases of dementia. MicroRNAs (miRNAs) are small non-coding RNAs that play a crucial role in gene expression regulation. Although the diagnosis of AD is primarily clinical, several miRNAs have been associated with AD and considered as potential markers for diagnosis and progression of AD. We sought to match AD-related miRNAs in cerebrospinal fluid (CSF) found in the GeoDataSets, evaluated by machine learning, with miRNAs listed in a systematic review, and a pathway analysis. Using machine learning approaches, we identified most differentially expressed miRNAs in Gene Expression Omnibus (GEO), which were validated by the systematic review, using the acronym PECO-Population (P): Patients with AD, Exposure (E): expression of miRNAs, Comparison (C): Healthy individuals, and Objective (O): miRNAs differentially expressed in CSF. Additionally, pathway enrichment analysis was performed to identify the main pathways involving at least four miRNAs selected. Four miRNAs were identified for differentiating between patients with and without AD in machine learning combined to systematic review, and followed the pathways analysis: miRNA-30a-3p, miRNA-193a-5p, miRNA-143-3p, miRNA-145-5p. The pathways epidermal growth factor, MAPK, TGF-beta and ATM-dependent DNA damage response, were regulated by these miRNAs, but only the MAPK pathway presented higher relevance after a randomic pathway analysis. These findings have the potential to assist in the development of diagnostic tests for AD using miRNAs as biomarkers, as well as provide understanding of the relationship between different pathophysiological mechanisms of AD.

The role of brain perfusion SPECT in the diagnosis of frontotemporal dementia: A systematic review.

BACKGROUND AND PURPOSE: Frontotemporal dementia (FTD) is the second most common cause of presenile dementia. The clinical distinction between FTD, Alzheimer's disease (AD), and other dementias is a clinical challenge. Brain perfusion SPECT may contribute to the diagnosis of FTD, but its value is unclear. METHODS: We performed a systematic review to investigate the diagnostic accuracy of the brain SPECT in (1) distinguishing FTD from AD and other dementias and (2) differentiating FTD variants. RESULTS: Overall, 391 studies were retrieved on the initial search and 35 studies composed the final selection, comprising a total number of 3142 participants of which 1029 had FTD. The sensitivity and the specificity for the differential diagnosis of FTD versus AD ranged from 56% to 88% and from 51% to 93%, respectively. SPECT is not superior to the clinical method of diagnosis, but the combination of SPECT with clinical data seems to improve the diagnostic accuracy. CONCLUSION: Brain perfusion SPECT has a limited value in the diagnostic framework of FTD. SPECT can be performed when FDG-PET is not available. SPECT is recommended only for selected cases when the diagnosis is challenging using conventional methods.

Clinical profile and survival analysis of Alzheimer's disease patients in a Brazilian cohort.

OBJECTIVE: To investigate the clinical and epidemiological characteristics of a large sample of patients with dementia due to Alzheimer's disease (AD) who were followed up at a cognitive neurology outpatient clinic. METHODS: Retrospective, longitudinal, and descriptive design. We collected data from patients with dementia due to AD who visited the outpatient clinic of the SARAH Network of Rehabilitation Hospitals in Rio de Janeiro, Brazil, between May 2009 and June 2019. The evaluated characteristics included age of onset, sex, education, family history, comorbidities, time until diagnosis, and survival rates. RESULTS: Overall, 1434 patients were evaluated, 74% of whom were women, with a mean age at symptom onset of 72.7 years and 75.8 at diagnosis. A positive family history was reported in 602 patients, with a first-degree relative in 86.3% of them. Hypertension was the most prevalent comorbidity, affecting 61.2% of the sample, and 16.2% were classified as having early-onset AD. The mean survival rate for the sample population was 112.8 months (9.4 years). The sample population was positively affected by dyslipidaemia. CONCLUSIONS: This study presents a clinical and epidemiological analysis of a large and diverse group of patients with AD. The study confirms previous observations such as a higher prevalence of AD in women, low education among sufferers, and the presence of a family history. The study also found that comorbidities significantly affected patient survival and provides new data on the survival rates of patients with early and late AD in the Brazilian population.

Optimal cardiovascular health is associated with slower cognitive decline.

BACKGROUND: Life's Simple 7, a lifestyle and cardiovascular index associated with cognition, has been updated to Life's Essential 8 (LE8) to include sleep. LE8 has been related to cardiovascular outcomes but its association with cognition is unclear. METHODS: In this longitudinal analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), LE8 score was based on health behaviors (diet, physical activity, nicotine exposure, and sleep health) as well as health-related factors (body mass index, blood lipids, blood glucose, and blood pressure). Cognition was assessed in three waves, 4 years apart, using the Consortium to Establish a Registry for Alzheimer's Disease - Word List, semantic and phonemic verbal fluency, the Trail-Making Test B (TMT-B), and a global composite score. We used linear mixed-model analysis, inverse probability weighting, and interaction analysis. RESULTS: At baseline, the mean age of the study cohort was 51.4 ± 8.9 years, 56% were women, and 53% were White. Higher baseline LE8 scores were associated with slower decline in global cognition (ß = 0.001, 95% confidence interval [CI] 0.001, 0.002; p < 0.001), memory (ß = 0.001, 95% CI 0.000, 0.002; p = 0.013), verbal fluency (ß = 0.001, 95% CI 0.000, 0.002; p = 0.003), and TMT-B (ß = 0.004, 95% CI 0.003, 0.005; p < 0.001). This association was mainly driven by LE8 health factors, particularly blood glucose and blood pressure. Age, sex, and race were modifiers of the association between LE8 and global cognitive decline (p < 0.001), suggesting it was more pronounced in older, male, and Black participants. CONCLUSIONS: Higher baseline LE8 scores were associated with slower global and domain-specific cognitive decline during 8 years of follow-up, mainly due to health factors such as blood glucose and blood pressure. Sociodemographic factors were modifiers of this association.

Efficacy of anti-amyloid-ß monoclonal antibody therapy in early Alzheimer's disease: a systematic review and meta-analysis.

BACKGROUND: Studies targeting amyloid-ß in patients with Alzheimer's disease (AD) have conflicting results and early initiation of therapy may yield better outcomes. METHODS: We systematically searched PubMed, Embase, Cochrane Library, and Clinicaltrials.gov for randomized trials comparing monoclonal antibodies (mAbs) with placebo in MCI or mild dementia due to AD. RESULTS: Nineteen studies comprising 15,275 patients were included. In patients with early AD, mAbs reduced the rate of decline, in both the Clinical Dementia Rating Scale, the sum of boxes (CDR-SB; MD -0.30; 95% CI -0.42,-0.19; p < 0.01), and the Alzheimer's Disease Assessment Scale, cognitive subscore (ADAS-cog; SMD -0.80; 95% CI -10.25,-0.35; p < 0.01). The results were similar between clinical stages for CDR-SB (MCI, MD -0.19; 95% CI -0.35,-0.03; p = 0.02; mild dementia, MD -0.45; 95% CI -0.65,-0.25; p < 0.01; subgroup differences, p = 0.13), as well as for ADAS-Cog (MCI, SMD -0.83; 95% CI -1.49,-0.17; p = 0.01; mild dementia, SMD -0.69; 95% CI -1.32 to -0.05; p = 0.03; subgroup differences, p = 0.47). The risk of amyloid-related imaging abnormalities (ARIA) was significantly higher in patients taking mAbs, including ARIA-edema (RR 7.7; 95% CI 4.60 to 13.00; p < 0.01), ARIA-hemorrhage (RR 1.8; 95% CI 1.22 to 2.59; p < 0.01), and symptomatic or serious ARIA (RR 14.1; 95% CI 7.30 to 27.14; p < 0.01). CONCLUSION: Anti-amyloid-ß mAbs attenuate cognitive and functional decline compared with placebo in early AD; whether the magnitude of this effect is clinically important remains uncertain, especially relative to the safety profile of these medications. Starting immunotherapy in patients with MCI was not significantly different than starting in the mild dementia stage. PROSPERO REGISTRY: CRD42023430698.

Diagnostic disclosure of Alzheimer's disease in Brazil: a national survey of specialized physicians.

BACKGROUND: The diagnosis of Alzheimer's disease (AD) can bring financial and emotional consequences to patients and caregivers. Whether or not the diagnosis should be disclosed to patients is a matter of debate amongst physicians and can be influenced by culture and experience. OBJECTIVE: To investigate the current practice of physicians who attend and treat patients with dementia in Brazil regarding the disclosure of dementia diagnosis and compare the practice with what has been performed 15 years ago in the country. METHODS: Data were evaluated using an electronic questionnaire. The questions used to carry out this research were similar to the questions of the study carried out 15 years ago 9. The form was sent to the Brazilian Academy of Neurology, the Brazilian Association of Geriatrics and Gerontology, and the Brazilian Association of Psychiatry, which forwarded it to their members. Analyses were conducted through non-parametric statistical tests, with a post-hoc assessment. RESULTS: 397 physicians responded to the survey, of which 231 are neurologists, 124 geriatricians, 29 psychiatrists and 13 from other specialties. The mean age was 45.2 years. The majority (66.7%) of the physicians reveal the diagnosis of AD always or usually. The youngest group of neurologists were more likely to disclose the diagnosis than the oldest group with a significant difference between them. In comparison to the 2008 Brazilian study, the percentage of physicians who always or usually disclose the diagnosis has risen by 22%. On the other hand, 12.3% of the physicians rarely or never disclose the diagnosis, in comparison to 25,3% in 2008. The main reasons for not disclosing the diagnosis concern the patients' mental health. CONCLUSION: Advances in dementia knowledge and biomarkers availability probably explain the increase in the rate of disclosure. The main challenge is to reconcile the autonomy of affected individuals, mental health issues after the diagnosis and the family member's opinion.

ANTECEDENTES: O diagnóstico da doença de Alzheimer (DA) pode trazer consequências financeiras e emocionais para pacientes e cuidadores. Revelar ou não o diagnóstico aos pacientes é uma questão de debate entre os médicos e pode ser influenciada pela cultura e experiência. OBJETIVO: Investigar a prática atual dos médicos que atendem e tratam pacientes com demência no Brasil quanto à revelação do diagnóstico de demência e comparar a prática com a qual era feita há 15 anos no país. MéTODOS:: Os dados foram avaliados por meio de um questionário eletrônico. As perguntas usadas para realização dessa pesquisa foram similares às perguntas do estudo realizado há 15 anos 9. O formulário foi enviado à Academia Brasileira de Neurologia, à Associação Brasileira de Geriatria e Gerontologia, e à Associação Brasileira de Psiquiatria, as quais o encaminharam aos seus membros. As análises foram realizadas por meio de testes estatísticos não paramétricos, com avaliação post-hoc. RESULTADOS: 397 médicos responderam à pesquisa, sendo 231 neurologistas, 124 geriatras, 29 psiquiatras e 13 de outras especialidades. A média de idade foi de 45,2 anos (standard deviation-SD = 11.6 years). A maioria (66,7%) dos médicos revela o diagnóstico de DA sempre ou habitualmente. O grupo mais jovem de neurologistas foi mais propenso a revelar o diagnóstico do que o mais velho, com diferença significativa entre eles. Em comparação com o estudo brasileiro de 2008, o percentual de médicos que sempre ou usualmente revelam o diagnóstico aumentou em 22%. Em contrapartida, 12,3% dos médicos raramente ou nunca o divulgam, em comparação a 25,3% em 2008. Os principais motivos para não o revelar dizem respeito à saúde mental dos pacientes. CONCLUSãO:: Avanços no conhecimento da demência e disponibilidade de biomarcadores provavelmente explicam o aumento na taxa de divulgação. O principal desafio é conciliar a autonomia dos indivíduos afetados, problemas de saúde mental após o diagnóstico e opinião do familiar.

Hearts and Minds: Emotion Recognition and Mentalizing in Parkinson's Disease and Progressive Supranuclear Palsy.

OBJECTIVE: There are scarce data comparing Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP) in social cognition (SC). We aimed to compare patients with PSP and PD in SC. METHODS: We included three groups: PD (n = 18), PSP (n = 20) and controls (n = 23). Participants underwent neuropsychological exams, including the mini-version of the Social and Emotional Assessment, which is composed of the facial emotion recognition test (FERT) and the modified faux-pas (mFP) test, which assesses Theory of Mind (ToM). RESULTS: Patients with PD scored lower than controls in the FERT, but not in the mFP test. Patients with PSP performed worse than controls in both the mFP and FERT. PD and PSP groups did not differ in the FERT, but PSP performed worse than PD in the mFP test. The mFP test distinguished PSP from PD with 89% accuracy. CONCLUSION: The assessment of ToM may contribute to the differentiation between PD and PSP.

The (in)visible Brazilians: A perspective review on the need for brain health and dementia research with Brazilian immigrants in the United States.

Introduction: The Brazilian population in the United States (U.S.), a Latinx subgroup, is rapidly growing and aging but remains underrepresented in U.S. health research. In addition to group-specific genetic and environmental risks, Brazilian immigrants and their offspring in the U.S. likely have cumulative risks for health inequities.It is estimated that 71% of Brazilian immigrants in the U.S. are undocumented, which may limit healthcare access/utilization. Furthermore, mental health is reported as a health priority by Brazilian immigrants in the U.S., and there is a lack of research on Alzheimer's disease and related dementia (AD/ADRD) in this population. Methods: We reviewed the scientific literature using traditional (e.g., PubMed) sources and databases generated by U.S. and Brazilian governments, as well as international organizations, and press articles. Results: This perspective review lists recommendations for researchers, health providers, and policymakers to promote greater inclusion of U.S. Brazilian populations in health research and care. The review identifies research areas in need of attention to address health inequities and promote mental/brain health in Brazilian immigrants and their offspring living in the U.S. These research areas are: 1) epidemiological studies to map the prevalence and incidence of mental/brain health conditions; 2) research on aging and AD/ADRD risk factors among Brazilian populations in the U.S.; and 3) the need for greater representation of U.S-residing Brazilian population in other relevant research areas involving genetics, neuropathology, and clinical trials. Conclusions: The recommendation and research efforts proposed should help to pave the way for the development of community-engagement research and to promote mental/brain health education, improvement of mental/brain health and AD/ADRD services, and the development of culturally-informed intervention to the U.S.-residing Brazilian communities. HIGHLIGHTS: The Brazilian population in the United States is growing but is underrepresented in U.S. health research.Approximately 71% of Brazilian immigrants in the United States are undocumented, with an increased risk for health inequities.Mental health is reported as a central health priority by Brazilian immigrants in the United States.There is a lack of research on Alzheimer's disease and other dementias (ADRD) in Brazilian immigrants in the United States.Epidemiological research is needed to map the prevalence/incidence of mental health conditions and ADRD risk factors among Brazilian immigrants in the United States.

Predicting Dementia Due to Alzheimer's Disease and Behavioral Variant Frontotemporal Dementia Using Algorithms with the Addenbrooke's Cognitive Examination-Revised Subscores Combined with Sociodemographic Factors.

BACKGROUND: Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are important causes of dementia with challenging differential diagnoses in many cases. Addenbrooke's Cognitive Examination-Revised (ACE-R) is a cognitive battery that may be useful to differentiate the two disorders. OBJECTIVE: The objectibe of this study is to investigate the value of the ACE-R combined with sociodemographic factors in the differential diagnosis between AD and bvFTD. METHODS: The ACE-R was administered to 102 patients with mild dementia due to probable AD, 37 with mild bvFTD, and 135 controls. Performances of patients and controls were analyzed by logistic regression and by ROC curves to refine the diagnostic accuracy of the ACE-R in AD and bvFTD. RESULTS: The ACE-R subscores Attention and Orientation, Fluency, and Memory, in combination with schooling differentiated AD from controls with an area under the ROC curve (AUC) of 0.936 (86% sensitivity and 87% specificity). The ACE-R subscores Attention and Orientation, Fluency, and Language, in combination with sex (male), age, and schooling, discriminated bvFTD from controls with an AUC of 0.908 (81% sensitivity and 95% specificity). In the differentiation between AD and bvFTD, the ACE-R subscores Attention and Orientation, Fluency, and Language, together with age, displayed an AUC of 0.865 (78% sensitivity and 85% specificity). CONCLUSION: The combination of ACE-R scores with sociodemographic data allowed good differentiation between AD and bvFTD in the study sample.

Literacy, but not memory, is associated with hippocampal connectivity in illiterate adults.

Background: The influence of hippocampal connectivity on memory performance is well established in individuals with high educational attainment. However, the role of hippocampal connectivity in illiterate populations remains poorly understood. Methods: Thirty-five illiterate adults were administered a literacy assessment (Test of Functional Health Literacy in Adults - TOFHLA), structural and resting state functional MRI and an episodic memory test (Free and Cued Selective Reminding Test). Illiteracy was defined as a TOFHLA score below 53. We evaluated the correlation between hippocampal connectivity at rest and both free recall and literacy scores. Results: Participants were mostly female (57.1%) and Black (84.8%), with a median age of 50 years. The median TOFHLA literacy score was 28.0 [21.0;42.5] out of 100 points and the median free recall score was 30.0 [26.2;35] out of 48 points. The median gray matter volume of both the left and right hippocampi was 2.3 [2.1; 2.4] cm3. We observed a significant connectivity between both hippocampi and the precuneus and the ventral medial prefrontal cortex. Interestingly, the right hippocampal connectivity positively correlated with the literacy scores (ß = 0.58, p = 0.008). There was no significant association between episodic memory and hippocampal connectivity. Neither memory nor literacy scores correlated with hippocampal gray matter volume. Conclusions: Low literacy levels correlate with hippocampal connectivity in illiterate adults. The lack of association with memory scores might be associated with low brain reserve in illiterate adults.

X-Chromosome Association Study in Latin American Cohorts Identifies New Loci in Parkinson's Disease.

BACKGROUND: Sex differences in Parkinson's disease (PD) risk are well-known. However, the role of sex chromosomes in the development and progression of PD is still unclear. OBJECTIVE: The objective of this study was to perform the first X-chromosome-wide association study for PD risk in a Latin American cohort. METHODS: We used data from three admixed cohorts: (1) Latin American Research consortium on the Genetics of Parkinson's Disease (n = 1504) as discover cohort, and (2) Latino cohort from International Parkinson Disease Genomics Consortium (n = 155) and (3) Bambui Aging cohort (n = 1442) as replication cohorts. We also developed an X-chromosome framework specifically designed for admixed populations. RESULTS: We identified eight linkage disequilibrium regions associated with PD. We replicated one of these regions (top variant rs525496; discovery odds ratio [95% confidence interval]: 0.60 [0.478-0.77], P = 3.13 × 10-5 replication odds ratio: 0.60 [0.37-0.98], P = 0.04). rs5525496 is associated with multiple expression quantitative trait loci in brain and non-brain tissues, including RAB9B, H2BFM, TSMB15B, and GLRA4, but colocalization analysis suggests that rs5525496 may not mediate risk by expression of these genes. We also replicated a previous X-chromosome-wide association study finding (rs28602900), showing that this variant is associated with PD in non-European populations. CONCLUSIONS: Our results reinforce the importance of including X-chromosome and diverse populations in genetic studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

A task force for diagnosis and treatment of people with Alzheimer's disease in Latin America.

Alzheimer's disease (AD) represents a substantial burden to patients, their caregivers, health systems, and society in Latin America and the Caribbean (LAC). This impact is exacerbated by limited access to diagnosis, specialized care, and therapies for AD within and among nations. The region has varied geographic, ethnic, cultural, and economic conditions, which create unique challenges to AD diagnosis and management. To address these issues, the Americas Health Foundation convened a panel of eight neurologists, geriatricians, and psychiatrists from Argentina, Brazil, Colombia, Ecuador, Guatemala, Mexico, and Peru who are experts in AD for a three-day virtual meeting to discuss best practices for AD diagnosis and treatment in LAC and create a manuscript offering recommendations to address identified barriers. In LAC, several barriers hamper diagnosing and treating people with dementia. These barriers include access to healthcare, fragmented healthcare systems, limited research funding, unstandardized diagnosis and treatment, genetic heterogeneity, and varying social determinants of health. Additional training for physicians and other healthcare workers at the primary care level, region-specific or adequately adapted cognitive tests, increased public healthcare insurance coverage of testing and treatment, and dedicated search strategies to detect populations with gene variants associated with AD are among the recommendations to improve the landscape of AD.