Exercise modifies hypothalamic connectivity and brain functional networks in women after bariatric surgery: a randomized clinical trial.

BACKGROUND: Obesity is a disease that may involve disrupted connectivity of brain networks. Bariatric surgery is an effective treatment for obesity, and the positive effects on obesity-related conditions may be enhanced by exercise. Herein, we aimed to investigate the possible synergistic effects of Roux-en-Y Gastric Bypass (RYGB) and exercise training on brain functional networks. METHODS: Thirty women eligible for bariatric surgery were randomly assigned to a Roux-en-Y gastric bypass (RYGB: n = 15, age = 41.0 ± 7.3 years) or RYGB plus Exercise Training (RYGB + ET: n = 15, age = 41.9 ± 7.2 years). Clinical, laboratory, and brain functional connectivity parameters were assessed at baseline, and 3 (POST3) and 9 months (POST9) after surgery. The 6-month, three-times-a-week, exercise intervention (resistance plus aerobic exercise) was initiated 3 months post-surgery (for RYGB + ET). RESULTS: Exercise superimposed on bariatric surgery (RYGB + ET) increased connectivity between hypothalamus and sensorial regions (seed-to-voxel analyses of hypothalamic connectivity), and decreased default mode network (DMN) and posterior salience (pSAL) network connectivity (ROI-to-ROI analyses of brain networks connectivity) when compared to RYGB alone (all p-FDR < 0.05). Increases in basal ganglia (BG) network connectivity were only observed in the exercised training group (within-group analyses). CONCLUSION: Exercise training is an important component in the management of post-bariatric patients and may improve the hypothalamic connectivity and brain functional networks that are involved in controlling food intake. TRIAL REGISTRATION: Clinicaltrial.gov: NCT02441361.

Risk factors for dementia in Brazil: Differences by region and race.

INTRODUCTION: Twelve risk factors (RFs) account for 40% of dementia cases worldwide. However, most data for population attributable fractions (PAFs) are from high-income countries (HIC). We estimated how much these RFs account for dementia cases in Brazil, stratifying estimates by race and socioeconomic level. METHODS: We calculated the prevalence and communalities of 12 RFs using 9412 Brazilian Longitudinal Study of Aging participants, then stratified according to self-reported race and country macro-regions. RESULTS: The overall weighted PAF was 48.2%. Less education had the largest PAF (7.7%), followed by hypertension (7.6%), and hearing loss (6.8%). PAF was 49.0% and 54.0% in the richest and poorest regions, respectively. PAFs were similar among White and Black individuals (47.8% and 47.2%, respectively) but the importance of the main RF varied by race. DISCUSSION: Brazil's potential for dementia prevention is higher than in HIC. Education, hypertension, and hearing loss should be priority targets.

Biomarkers for dementia in Latin American countries: Gaps and opportunities.

Limited knowledge on dementia biomarkers in Latin American and Caribbean (LAC) countries remains a serious barrier. Here, we reported a survey to explore the ongoing work, needs, interests, potential barriers, and opportunities for future studies related to biomarkers. The results show that neuroimaging is the most used biomarker (73%), followed by genetic studies (40%), peripheral fluids biomarkers (31%), and cerebrospinal fluid biomarkers (29%). Regarding barriers in LAC, lack of funding appears to undermine the implementation of biomarkers in clinical or research settings, followed by insufficient infrastructure and training. The survey revealed that despite the above barriers, the region holds a great potential to advance dementia biomarkers research. Considering the unique contributions that LAC could make to this growing field, we highlight the urgent need to expand biomarker research. These insights allowed us to propose an action plan that addresses the recommendations for a biomarker framework recently proposed by regional experts.

Effects of dabigatran versus warfarin on 2-year cognitive outcomes in old patients with atrial fibrillation: results from the GIRAF randomized clinical trial.

BACKGROUND: Observational studies support a role for oral anticoagulation to reduce the risk of dementia in atrial fibrillation patients, but conclusive data are lacking. Since dabigatran offers a more stable anticoagulation, we hypothesized it would reduce cognitive decline when compared to warfarin in old patients with atrial fibrillation. METHODS: The GIRAF trial was a 24-month, randomized, parallel-group, controlled, open-label, hypothesis generating trial. The trial was done in six centers including a geriatric care unit, secondary and tertiary care cardiology hospitals in São Paulo, Brazil. We included patients aged ≥ 70 years and CHA2DS2-VASc score > 1. The primary endpoint was the absolute difference in cognitive performance at 2 years. Patients were assigned 1:1 to take dabigatran (110 or 150 mg twice daily) or warfarin, controlled by INR and followed for 24 months. Patients were evaluated at baseline and at 2 years with a comprehensive and thorough cognitive evaluation protocol of tests for different cognitive domains including the Montreal Cognitive Assessment (MoCA), Mini-Mental State Exam (MMSE), a composite neuropsychological test battery (NTB), and computer-generated tests (CGNT). RESULTS: Between 2014 and 2019, 5523 participants were screened and 200 were assigned to dabigatran (N = 99) or warfarin (N = 101) treatment. After adjustment for age, log of years of education, and raw baseline score, the difference between the mean change from baseline in the dabigatran group minus warfarin group was - 0.12 for MMSE (95% confidence interval [CI] - 0.88 to 0.63; P = 0.75), 0.05 (95% CI - 0.07 to 0.18; P = 0.40) for NTB, - 0.15 (95% CI - 0.30 to 0.01; P = 0.06) for CGNT, and - 0.96 (95% CI - 1.80 to 0.13; P = 0.02) for MoCA, with higher values suggesting less cognitive decline in the warfarin group. CONCLUSIONS: For elderly patients with atrial fibrillation, and without cognitive compromise at baseline that did not have stroke and were adequately treated with warfarin (TTR of 70%) or dabigatran for 2 years, there was no statistical difference at 5% significance level in any of the cognitive outcomes after adjusting for multiple comparisons. TRIAL REGISTRATION: Cognitive Impairment Related to Atrial Fibrillation Prevention Trial (GIRAF), NCT01994265 .

Working Group Recommendations for the Practice of Teleneuropsychology in Latin America.

OBJECTIVE: Teleneuropsychology (teleNP) could potentially expand access to services for patients who are confined, have limited personal access to healthcare, or live in remote areas. The emergence of the COVID-19 pandemic has significantly increased the use of teleNP for cognitive assessments. The main objective of these recommendations is to identify which procedures can be potentially best adapted to the practice of teleNP in Latin America, and thereby facilitate professional decision-making in the region. METHOD: Steps taken to develop these recommendations included (1) formation of an international working group with representatives from 12 Latin American countries; (2) assessment of rationale, scope, and objectives; (3) formulation of clinical questions; (4) evidence search and selection; (5) evaluation of existing evidence and summary; and (6) formulation of recommendations. Levels of evidence were graded following the Oxford Centre for Evidence-Based Medicine system. Databases examined included PubMed, WHO-IRIS, WHO and PAHO-IRIS, Índice Bibliográfico Español en Ciencias de la Salud (IBCS), and LILACS. RESULTS: Working group members reviewed 18,400 titles and 422 abstracts and identified 19 articles meeting the criteria for level of evidence, categorization, and elaboration of recommendations. The vast majority of the literature included teleNP tests in the English language. The working group proposed a series of recommendations that can be potentially best adapted to the practice of teleNP in Latin America. CONCLUSIONS: There is currently sufficient evidence to support the use of videoconferencing technology for remote neuropsychological assessments. These recommendations will likely contribute to the advancement of teleNP research and practice in the region.

Incidence of dementia in a Brazilian population: The Tremembé Epidemiologic Study.

INTRODUCTION: Few dementia incidence studies have been performed in Latin America. We aimed to provide the incidence of dementia in a Brazilian community-dwelling elderly population. METHODS: This study was conducted in urban and rural areas of Tremembé. The 520 participants without dementia at baseline were invited to participate in the follow-up. RESULTS: After a median follow-up of 5 years, the incidence rate of dementia was 26.1 per 1000 person-years (PY) (95% confidence interval  = 18.7-36.6/1000PY). This rate increased exponentially with age (8.3/1000PY for 60- to 64-year-olds to 110.2/1000PY for ≥80-year-olds) and lower education (10.5/1000PY for > 8 years of education to 59.2/1000PY for illiterates). Higher dementia risk was found among individuals with cognitive impairment no dementia at baseline. DISCUSSION: The dementia incidence rate found was higher than in other countries in people under 65 years. Higher incidence in younger individuals is expected in developing countries probably due to low education and a high burden of cardiovascular diseases.

Dementia caregiving across Latin America and the Caribbean and brain health diplomacy.

The prevalence of dementia in Latin America and the Caribbean is growing rapidly, increasing the burden placed on caregivers. Exacerbated by fragile health-care systems, unstable economies, and extensive inequalities, caregiver burden in this region is among the highest in the world. We reviewed the major challenges to caregiving in Latin America and the Caribbean, and we propose regional and coordinated actions to drive future change. Current challenges include the scarcity of formal long-term care, socioeconomic and social determinants of health disparities, gender-biased burdens, growing dementia prevalence, and the effect of the current COVID-19 pandemic on families affected by dementia. Firstly, we propose local and regional short-term strategic recommendations, including systematic identification of specific caregiver needs, testing of evidence-based local interventions, contextual adaptation of strategies to different settings and cultures, countering gender bias, strengthening community support, provision of basic technology, and better use of available information and communications technology. Additionally, we propose brain health diplomacy (ie, global actions aimed to overcome the systemic challenges to brain health by bridging disciplines and sectors) and convergence science as frameworks for long-term coordinated responses, integrating tools, knowledge, and strategies to expand access to digital technology and develop collaborative models of care. Addressing the vast inequalities in dementia caregiving across Latin America and the Caribbean requires innovative, evidence-based solutions coordinated with the strengthening of public policies.

Virtual Support in Dementia: A Possible Viable Strategy for Caregivers.

Background: In the last 10 months, due to the Covid-19 pandemic, several studies have shown that health education and virtual support strategies for caregivers of patients with dementia, in the management of home care, can be viable. Low and middle income countries, in particular, have sought to use these means to reduce the daily burden of caregivers, through virtual meetings of education and support. Objectives: To present the feasibility of a pilot study on the use of a support action contemplated by the Caad Project-indirect costs of dementia-from HC-FMUSP. Methods: Observational study in which 93 caregivers were invited to participate in virtual meetings on a frequency of three times/week, lasting 1 h each. Results: Of the 93 invited family members, and after 3 months, 42 answered eight questions about the effectiveness of the action. High percentages of positive responses regarding program satisfaction ranged from 86 to 100%. Conclusion: This study showed results of a very simple intervention that suggests that it is possible to offer caregivers of patients with dementia a program that can be used in primary care, in order to understand the difficulty of caregivers in their daily care of patients with dementia, with daily management guidelines on a case-by-case basis, in addition to promoting the implementation of an education strategy about the importance of knowing, and recognizing anatomophysiological changes in the aging process and its implications for the rupture of the imaginary line that involves senescence and senility. This allows the caregiver to feel able to protect his patient and himself by preventing the emergence of common diseases in this age group. Further studies are needed to explore this type of non-pharmacological support.

The Multi-Partner Consortium to Expand Dementia Research in Latin America (ReDLat): Driving Multicentric Research and Implementation Science.

Dementia is becoming increasingly prevalent in Latin America, contrasting with stable or declining rates in North America and Europe. This scenario places unprecedented clinical, social, and economic burden upon patients, families, and health systems. The challenges prove particularly pressing for conditions with highly specific diagnostic and management demands, such as frontotemporal dementia. Here we introduce a research and networking initiative designed to tackle these ensuing hurdles, the Multi-partner consortium to expand dementia research in Latin America (ReDLat). First, we present ReDLat's regional research framework, aimed at identifying the unique genetic, social, and economic factors driving the presentation of frontotemporal dementia and Alzheimer's disease in Latin America relative to the US. We describe ongoing ReDLat studies in various fields and ongoing research extensions. Then, we introduce actions coordinated by ReDLat and the Latin America and Caribbean Consortium on Dementia (LAC-CD) to develop culturally appropriate diagnostic tools, regional visibility and capacity building, diplomatic coordination in local priority areas, and a knowledge-to-action framework toward a regional action plan. Together, these research and networking initiatives will help to establish strong cross-national bonds, support the implementation of regional dementia plans, enhance health systems' infrastructure, and increase translational research collaborations across the continent.

Disease Progression in Frontotemporal Dementia and Alzheimer Disease: The Contribution of Staging Scales.

INTRODUCTION: There is a shortage of validated instruments to estimate disease progression in frontotemporal dementia (FTD). OBJECTIVES: To evaluate the ability of the FTD Rating Scale (FTD-FRS) to detect functional and behavioral changes in patients diagnosed with the behavioral variant of FTD (bvFTD), primary progressive aphasia (PPA), and Alzheimer disease (AD) after 12 months of the initial evaluation, compared to the Clinical Dementia Rating scale-frontotemporal lobar degeneration (CDR-FTLD) and the original Clinical Dementia Rating scale (CDR). METHODS: The sample consisted of 70 individuals, aged 40+ years, with at least 2 years of schooling, 31 with the diagnosis of bvFTD, 12 with PPA (8 with semantic variant and 4 with non-fluent variant), and 27 with AD. The FTD-FRS, the CDR, and the 2 additional CDR-FTLD items were completed by a clinician, based on the information provided by the caregiver with frequent contact with the patient. The Addenbrooke Cognitive Examination-Revised was completed by patients. After 12 months, the same protocol was applied. RESULTS: The FTD-FRS, CDR-FTLD, and CDR detected significant decline after 12 months in the 3 clinical groups (exception: FTD-FRS for PPA). The CDR was less sensitive to severe disease stages. CONCLUSIONS: The FTD-FRS and the CDR-FTLD are especially useful tools for dementia staging in AD and in the FTD spectrum.

Mnemonic strategy training modulates functional connectivity at rest in mild cognitive impairment: Results from a randomized controlled trial.

INTRODUCTION: Mnemonic strategy training (MST) has been shown to improve cognitive performance and increase brain activation in those with mild cognitive impairment (MCI). However, little is known regarding the effects of MST on functional connectivity (FC) at rest. The aim of the present study was to investigate the MST focused on face-name associations effect on resting-state FC in those with MCI. METHODS: Twenty-six amnestic MCI participants were randomized in MST (N = 14) and Education Program (active control; N = 12). Interventions occurred twice a week over two consecutive weeks (ie, four sessions). Resting-state functional magnetic resonance imaging was collected at pre- and post-intervention. Regions of interest (ROIs) were selected based on areas that previously showed task-related activation changes after MST. Changes were examined through ROI-to-ROI analysis and significant results were corrected for multiple comparisons. RESULTS: At post-intervention, only the MST group showed increased FC, whereas the control group showed decreased or no change in FC. After MST, there was an increased FC between the left middle temporal gyrus and right orbitofrontal cortex. In addition, a time-by-group interaction indicated that the MST group showed greater increased FC between the right inferior frontal gyrus and left brain regions, such as fusiform gyrus, temporal pole, and orbitofrontal cortex relative to controls. DISCUSSION: MST enhanced FC in regions that are functionally relevant for the training; however, not in all ROIs investigated. Our findings suggest that MST-induced changes are reflected in task-specific conditions, as previously reported, but also in general innate connectivity. Our results both enhance knowledge about the mechanisms underlying MST effects and may provide neurophysiological evidence of training transfer.

Second-Generation RT-QuIC Assay for the Diagnosis of Creutzfeldt-Jakob Disease Patients in Brazil.

The recent development of IQ-CSF, the second generation of real-time quaking-induced conversion (RT-QuIC) using cerebrospinal fluid (CSF), for the diagnosis of Creutzfeldt-Jakob Disease (CJD) represents a major diagnostic advance in the field. Highly accurate results have been reported with encouraging reproducibility among different centers. However, availability is still insufficient, and only a few research centers have access to the method in developing countries. In Brazil, we have had 603 suspected cases of CJD since 2005, when surveillance started. Of these, 404 were undiagnosed. This lack of diagnosis is due, among other factors, to the lack of a reference center for the diagnosis of these diseases in Brazil, resulting in some of these samples being sent abroad for analysis. The aim of this research study is to report the pilot use of IQ-CSF in a small cohort of Brazilian patients with possible or probable CJD, implementing a reference center in the country. We stored CSF samples from patients with possible, probable or genetic CJD (one case) during the time frame of December 2016 through June 2018. All CSF samples were processed according to standardized protocols without access to the clinical data. Eight patients presented to our team with rapidly progressive dementia and typical neurological signs of CJD. We used CSF samples from seven patients with other neurological conditions as negative controls. Five out of seven suspected cases had positive tests; two cases showed inconclusive results. Among controls, there was one false-positive (a CSF sample from a 5-year-old child with leukemia under treatment). The occurrence of a false positive in one of the negative control samples raises the possibility of the presence of interfering components in the CSF sample from patients with non-neurodegenerative pathologies. Our pilot results illustrate the feasibility of having CJD CSF samples tested in Brazilian centers and highlight the importance of interinstitutional collaboration to pursue a higher diagnostic accuracy in CJD in Brazil and Latin America.

Training gains and transfer effects after mnemonic strategy training in mild cognitive impairment: A fMRI study.

Prior work has revealed that mnemonic strategy training (MST) can enhance memory for specific content and engages regions in the frontoparietal cognitive control network. Evidence of transfer to novel content is less clear. Here, we provide secondary analysis of functional magnetic resonance imaging (fMRI) data acquired during a randomized controlled trial that compared MST to an active education control condition in patients with amnestic mild cognitive impairment (a-MCI). In the trial, thirty participants with a-MCI were randomized to the education program (EP) or MST, where they learned to apply the technique to face-name associations during four intervening hour long training sessions. Participants underwent pre- and post-training fMRI scans, during which they encoded both the trained (i.e., those used during the four training sessions) and untrained ('novel') face-name associations. The primary cognitive outcome measures revealed significantly improved memory for both trained and novel stimuli - effects supporting near transfer of MST. Relative to pre-training, there were significant and highly similar increases in activation for both trained and novel stimuli, especially in regions associated with the frontoparietal cognitive control network bilaterally, but also in temporal areas related to social cognition and emotional processing. Critically, this pattern of activation was notably different from the EP group. Thus, the changes in activation were consistent with the strategies trained and, combined with the cognitively-based near transfer effects, suggest that MST focused on face-name association enhances performance by engaging cognitive control and social/emotional processing. Finally, our data indicated that our MST is a relevant and efficient intervention to a-MCI.

MoCA Test: normative and diagnostic accuracy data for seniors with heterogeneous educational levels in Brazil.

INTRODUCTION: The Montreal Cognitive Assessment (MoCA) has been described as a good tool to detect cognitive impairment. The ideal MoCA cutoff score is still under debate. The aim was to provide MoCA norms and accuracy data for seniors with a lower education level, including illiterates. METHODS: Data originated from an epidemiological study conducted in the municipality of Tremembe, Brazil. The Brazilian MoCA test was applied as part of the cognitive assessment in all participants. Of the 630 participants, 385 were classified as cognitively normal (CN) and were included in the normative data set, 110 individuals were diagnosed with dementia and 135 were classified as having cognitive impairment no dementia (CIND). RESULTS: The total scores varied significantly according to age and education among the three diagnostic groups: CN, CIND and dementia (p < 0.001). To distinguish participants with CN from dementia, the best MoCA cutoff was 15 points (sensitivity 90%, specificity 77%) and to differentiate those with CN from CIND, the MoCA cutoff was 19 points (sensitivity 84%, specificity 49%). Those scores varied according to education level. CONCLUSIONS: The MoCA test did not have a high accuracy for detecting CIND in the population with a low educational level. Nevertheless, this tool may be used to detect dementia, especially in individuals with more than five years of education, if a lower cutoff score is adopted.

MoCA Test: normative and diagnostic accuracy data for seniors with heterogeneous educational levels in Brazil / Teste MoCA: dados normativos e de acurácia diagnóstica para idosos com níveis educacionais heterogêneos no Brasil

ABSTRACT The Montreal Cognitive Assessment (MoCA) has been described as a good tool to detect cognitive impairment. The ideal MoCA cutoff score is still under debate. The aim was to provide MoCA norms and accuracy data for seniors with a lower education level, including illiterates. Methods: Data originated from an epidemiological study conducted in the municipality of Tremembe, Brazil. The Brazilian MoCA test was applied as part of the cognitive assessment in all participants. Of the 630 participants, 385 were classified as cognitively normal (CN) and were included in the normative data set, 110 individuals were diagnosed with dementia and 135 were classified as having cognitive impairment no dementia (CIND). Results: The total scores varied significantly according to age and education among the three diagnostic groups: CN, CIND and dementia (p < 0.001). To distinguish participants with CN from dementia, the best MoCA cutoff was 15 points (sensitivity 90%, specificity 77%) and to differentiate those with CN from CIND, the MoCA cutoff was 19 points (sensitivity 84%, specificity 49%). Those scores varied according to education level. Conclusions: The MoCA test did not have a high accuracy for detecting CIND in the population with a low educational level. Nevertheless, this tool may be used to detect dementia, especially in individuals with more than five years of education, if a lower cutoff score is adopted.

RESUMO O Montreal Cognitive Assessment (MoCA) foi descrito como uma boa ferramenta para detectar comprometimento cognitivo. A nota de corte ideal do MoCA ainda está em debate. O objetivo é fornecer normas do MoCA e dados de acurácia para idosos dentro de uma faixa educacional mais baixa, incluindo analfabetos. Métodos: Os dados foram provenientes do estudo epidemiológico realizado no município de Tremembé, Brasil. A versão brasileira do MoCA foi aplicada como parte da avaliação cognitiva em todos os participantes. Dos 630 participantes, 385 foram classificados como cognitivamente normais (CN) e foram incluídos no conjunto de dados normativos, 110 indivíduos foram diagnosticados com demência e 135 foram classificados como tendo comprometimento cognitivo sem demência (CCSD). Resultados: Os escores totais variaram significativamente de acordo com a idade e escolaridade entre os três grupos diagnósticos: CN, CCSD e demência (p < 0,001). Para distinguir CN de demência, a melhor nota de corte do MoCA foi de 15 pontos (sensibilidade 90%, especificidade 77%) e para diferenciar o grupo CN de CCSD, a nota de corte do MoCA foi de 19 pontos (sensibilidade 84%, especificidade 49%). Essas notas de corte variaram conforme o nível de escolaridade. Conclusões: O teste MoCA não teve alta acurácia para detectar CCSD nesta população de baixa escolaridade. No entanto, esta ferramenta poderia ser usada para detectar demência, especialmente em indivíduos com mais de 5 anos de escolaridade, se uma menor nota de corte fosse adotada.

Adherence to the Mediterranean and MIND diets is associated with better cognition in healthy seniors but not in MCI or AD.

BACKGROUND: Dietary habits have become the focus of intensive research in cognitive aging and neurodegenerative diseases, showing potential to promote and maximize cognitive function. AIM: The aim was to investigate the association between the degree of adherence to the Mediterranean and MIND diets and cognitive performance in elderly with different cognitive profiles. METHODS: Cross-sectional study with participants from neurology outpatient clinic. PARTICIPANTS: A total of 96 individuals were classified by a multidisciplinary team into normal controls (NC), individuals with mild cognitive impairment, and Alzheimer's disease. MEASUREMENTS: The Brief Cognitive Screening Battery, Mini-Mental State Examination, and a 98-item food frequency questionnaire were applied. Anthropometric data were also collected. Adherence scores to the Mediterranean and MIND diets were subsequently calculated. RESULTS: Clinical groups did not differ regarding body mass index or level of adherence to the diets. Greater adherence to the Mediterranean and MIND diets was associated with higher scores on the MMSE and BCSB Learning in the NC group only. CONCLUSIONS: Moderate adherence to the Mediterranean and MIND dietary patterns may be associated with better cognition among healthy seniors living in middle to low income countries.