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.

Phenotyping Superagers Using Resting-State fMRI

BACKGROUND AND PURPOSE

Superagers are defined as older adults with episodic memory performance similar or superior to that in middle-aged adults. This study aimed to investigate the key differences in discriminative networks and their main nodes between superagers and cognitively average elderly controls. In addition, we sought to explore differences in sensitivity in detecting these functional activities across the networks at 3T and 7T MR imaging fields.

MATERIALS AND METHODS

Fifty-five subjects 80 years of age or older were screened using a detailed neuropsychological protocol, and 31 participants, comprising 14 superagers and 17 cognitively average elderly controls, were included for analysis. Participants underwent resting-state-fMRI at 3T and 7T MR imaging. A prediction classification algorithm using a penalized regression model on the measurements of the network was used to calculate the probabilities of a healthy older adult being a superager. Additionally, ORs quantified the influence of each node across preselected networks.

RESULTS

The key networks that differentiated superagers and elderly controls were the default mode, salience, and language networks. The most discriminative nodes (ORs > 1) in superagers encompassed areas in the precuneus posterior cingulate cortex, prefrontal cortex, temporoparietal junction, temporal pole, extrastriate superior cortex, and insula. The prediction classification model for being a superager showed better performance using the 7T compared with 3T resting-state-fMRI data set.

CONCLUSIONS

Our findings suggest that the functional connectivity in the default mode, salience, and language networks can provide potential imaging biomarkers for predicting superagers. The 7T field holds promise for the most appropriate study setting to accurately detect the functional connectivity patterns in superagers.

Risk of all-cause mortality and its association with health status in a cohort of community-dwelling older people: FIBRA study

This article aims to estimate the risk of death according to sociodemographic characteristics, chronic diseases, frailty, functional capacity, and social participation in older people as well as determine the median time of death in relation to health status and social participation. A retrospective longitudinal study was conducted with older people (≥65 years) in 2008-09 and 2016-17 in the city of Campinas and the subdistrict of Ermelino Matarazzo in the city of São Paulo. Face-to-face interviews were conducted at community centers and the participants' homes. The cumulative incidence of death was estimated and associations with the predictor variables were analyzed using Poisson multiple regression. The Kaplan-Meier method and the log-rank test were also used. Among the 741 individuals located at follow-up, 192 had deceased. The incidence of death was higher among those who reported having heart disease and those who were dependent on others regarding the performance of instrumental activities of daily living. The incidence of death was lower among women, individuals in the highest income stratum, and those who performed three or more activities related to social inclusion. No differences in median survival times were found. Predictors of mortality can contribute to broadening knowledge on the singularities of the aging process.

Impact of functional capacity on change in self-rated health among older adults in a nine-year longitudinal study

The aims of the present study were to estimate the frequency of change in self-rated health (SRH) among community-dwelling older adults, between two measures taken at a 9-year interval; and determine factors associated with a decline and an improvement in SRH, in relation to aspects of physical/emotional health and subjective wellbeing. Data were derived from a community-based study on frailty among Brazilian elderly. Associations were investigated using Pearson’s chi-square test and relative risk ratios were estimated using multinomial logistic regression analysis. 39.3% of participants did not change their SRH at both assessment times, 21.7% rated it as worse and 39.0% rated it as better. The relative risk ratio of an improvement in SRH for individuals with disability in basic activities of daily living (ADLs) was lower than for individuals with independence in basic ADLs (IRR=0.22; IC95%: 0.08-0.63). Understanding the complex interactions between self-rated health and the dimensions that influence the improvement of health perception may shed light on key determinants of the wellbeing among older adults.

Neuropsychiatric Symptoms in Behavioral Variant Frontotemporal Dementia and Alzheimer's Disease: A 12-Month Follow-Up Study

Introduction: Neuropsychiatric symptoms in patients with frontotemporal dementia (FTD) are highly prevalent and may complicate clinical managements.

Objective: To test whether the Neuropsychiatry Inventory (NPI) could detect change in neuropsychiatric symptoms and caregiver's distress in patients diagnosed with behavioral variant frontotemporal dementia (bvFTD) and Alzheimer's disease (AD) from baseline to a 12-month follow-up and to investigate possible predictors of change in NPI scores.

Methods: The sample consisted of 31 patients diagnosed with bvFTD and 28 patients with AD and their caregivers. The Mini-Mental State Examination (MMSE), Addenbrooke's Cognitive Examination Revised (ACE-R), the INECO Frontal Screening (IFS), the Frontal Assessment Battery (FAB), the Executive Interview (EXIT-25) and the NPI were applied. Descriptive statistics, Mann-Whitney U test, Wilcoxon test, Chi square (χ²) test and Linear Regression Analysis were used.

Results: NPI total and caregiver distress scores were statistically higher among bvFTD patients at both assessment points. MMSE, ACE-R scores significantly declined and NPI Total and Distress scores significantly increased in both groups. In the bvFTD group, age was the only independent predictor variable for the NPI total score at follow up. In the AD group, ACE-R and EXIT-25, conjunctively, were associated with the NPI total score at follow up.

Conclusions: In 12 months, cognition declined and neuropsychiatric symptoms increased in bvFTD and AD groups. In the AD group only, cognitive impairment was a significant predictor of change in neuropsychiatric symptoms.

The Brain Metabolic Signature in Superagers Using In Vivo 1H-MRS: A Pilot Study

BACKGROUND AND PURPOSE

Youthful memory performance in older adults may reflect an underlying resilience to the conventional pathways of aging. Subjects having this unusual characteristic have been recently termed "superagers." This study aimed to explore the significance of imaging biomarkers acquired by ¹H-MRS to characterize superagers and to differentiate them from their normal-aging peers.

MATERIALS AND METHODS

Fifty-five patients older than 80 years of age were screened using a detailed neuropsychological protocol, and 25 participants, comprising 12 superagers and 13 age-matched controls, were statistically analyzed. We used state-of-the-art 3T ¹H-MR spectroscopy to quantify 18 neurochemicals in the posterior cingulate cortex of our subjects. All ¹H-MR spectroscopy data were analyzed using LCModel. Results were further processed using 2 approaches to investigate the technique accuracy: 1) comparison of the average concentration of metabolites estimated with Cramer-Rao lower bounds <20%; and 2) calculation and comparison of the weighted means of metabolites' concentrations.

RESULTS

The main finding observed was a higher total N-acetyl aspartate concentration in superagers than in age-matched controls using both approaches (P = .02 and P = .03 for the weighted means), reflecting a positive association of total N-acetyl aspartate with higher cognitive performance.

CONCLUSIONS

¹H-MR spectroscopy emerges as a promising technique to unravel neurochemical mechanisms related to cognitive aging in vivo and providing a brain metabolic signature in superagers. This may contribute to monitoring future interventional therapies to avoid or postpone the pathologic processes of aging.

Which anthropometric measures best identify excess weight in older adults?

OBJECTIVES: To estimate the prevalence of and factors associated with excess weight in older adults according to body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WtHR), as well as to measure the differences between the prevalences estimated by WC and WtHR in relation to BMI. METHODS: This cross-sectional study was conducted in 2016 – 2017 with 549 older adults (72–102 years) from Campinas and Ermelino Matarazzo, two cities in the state of São Paulo, Brazil. Excess weight was defined according to cut-off points established for older adults. Multiple Poisson regression analysis was performed. RESULTS: The overweight/obesity prevalences were 47.36% (BMI), 61.38% (WC) and 65.57% (WtHR), being higher in women and in those with hypertension, diabetes, polypharmacy, and normal calf circumference. They were also higher in the youngest age strata (BMI and WC), in those with arthritis/rheumatism (BMI), and in those with slow gait (WtHR). The estimated overweight/obesity prevalences according to WC and WtHR were 29.00% and 38.00% higher, respectively, than BMI. In the multiple model, there was a higher prevalence of adiposity among diabetics and those with normal calf circumference. CONCLUSIONS: Measures of abdominal adiposity provided a better diagnosis of excess weight. We recommended that health professionals consider using WtHR in anthropometric assessment of older adults, especially regarding adiposity.

Evaluation of cerebral autoregulation performance in patients with arterial hypertension on drug treatment

Cerebral autoregulation (AR) keeps cerebral blood flow constant despite fluctuations in systemic arterial pressure. The final common AR pathway is made up of vasomotor adjustments of cerebrovascular resistance mediated by arterioles. Structural and functional changes in the arteriolar wall arise with age and systemic arterial hypertension. This study evaluated whether AR is impaired in hypertensive patients and whether this impairment differs with disease control. Three groups of patients were prospectively compared: hypertensive patients under treatment with systolic blood pressure (SBP) <140 and diastolic blood pressure (DBP) <90 mm Hg (n = 54), hypertensive patients under treatment with SBP > 140 or DBP > 90 mm Hg (n = 31), and normotensive volunteers (n = 30). Simultaneous measurements of cerebral blood flow velocity (CBFV) and BP were obtained by digital plethysmography and transcranial Doppler, and the AR index (ARI) was defined according to the step response to spontaneous fluctuations in BP. Compared to the uncontrolled hypertension, the normotensive individuals were younger (age 43.42 ± 11.14, P < .05) and had a lower resistance-area product (1.17 ± 0.24, P < .05), although age and greater arteriolar stiffness did not affect the CBFV mean of hypertensive patients, whether controlled or uncontrolled (62.85 × 58.49 × 58.30 cm/s, P = .29), most likely because their ARIs were not compromised (5.54 × 5.91 × 5.88, P = .6). Hypertensive patients under treatment, regardless of their BP control, have intact AR capacity.

Systemic arterial hypertension and cognition in adults: effects on executive functioning

BACKGROUND

Central nervous system changes associated to systemic arterial hypertension (SAH) are progressive and may cause negative effects on cognitive performance. The objective of this study was to investigate the relation between SAH and the components of executive functions (EF), inhibitory control (IC), updating and shifting, comparing a control group (without SAH) to patients with SAH, in two levels of severity.

METHODS

The protocol included the following tests to evaluate EF components: T.O.V.A. Test (IC), Backward Digit Span from Wechsler Adults Intelligence Scale (WAIS-III), Phonemic and Semantic Verbal Fluency (updating), and Trail Making Test Part B (shifting).

RESULTS

A total of 204 participants was included: 56 from the Control Group (CG), 87 SAH stage 1, and 61 SAH stage 2. The groups were not different for age (52.37±12.29) and education (10.98±4.06). As to controlled blood pressure (BP), duration of hypertension treatment and number of drugs, the SAH 2 group had a worse BP control, longer duration of hypertension treatment and use of more drugs when compared to the SAH 1. The findings revealed that patients with more severe hypertension presented worse performance in updating (Backward Digit Span, phonemic and semantics VF) and shifting (Trail Making Test Part B).

CONCLUSION

The results suggest that patients with SAH have a significant impairment in EF, more specifically in updating and shifting. Besides that, such damage may be directly proportional to the severity of SAH. It is suggested that future studies include neuroimaging exams to exclude possible cerebrovascular diseases.

Prevalence of Frailty in Brazilian Older Adults: A Systematic Review and Meta-analysis

OBJECTIVES

Frailty is characterized by a functioning decline in multiple systems accompanied by an increase in individual's vulnerability to stressors. It appears to be higher in low and middle-income countries compared with high-income ones. This study aimed to evaluate the prevalence of frailty in non-institutionalized Brazilian older adults.

DESIGN

a systematic review and meta-analysis study.

SETTING

Cross-sectional and prospective data from Brazil.

PARTICIPANTS

non-institutionalized adults aged 60 and older.

METHODS

Electronic searches were performed in PubMed/MEDLINE, LILACS, SCOPUS and Web of Science, considering the studies published between March 2001 and July 2018, using a combination of the following terms and correlates: "elder" AND "frail" AND "prevalence" AND "Brazil". Two independent reviewers selected studies according to the inclusion criteria. Disagreements were resolved by a third reviewer (title/abstract) and by consensus. Studies with samples ≥221 subjects were considered for meta-analysis.

RESULTS

28 studies were included, while 18 had the data meta-analyzed. The majority of studies (61%) included older adults only from the Southeastern region. The number of subjects ranged from 53 to 5,532 individuals (N = 17,604) and the average age ranged from 65.6 to 85.5 years. The overall prevalence of frailty was 24%. When considering the different assessment methods, the prevalence was lower for frailty phenotype (16%) compared with other criteria (40%). Regarding sex, the prevalence of frailty was similar for women (28%) and men (25%). The prevalence of frailty was higher in older adults recruited from health care services (30%) compared to community ones (22%).

CONCLUSION

In Brazil, the overall prevalence of frailty in non-institutionalized older adults is higher than observed from more developed countries. However, it may vary according to the assessment methods and settings.

Dor crônica em idosos e associações diretas e indiretas com variáveis sociodemográficas e de condições de saúde: uma análise de caminhos

Resumo Objetivo Identificar a prevalência de dor crônica em idosos acima de 70 anos de idade e as relações diretas e indiretas entre dor crônica e variáveis sociodemográficas e de condições de saúde. Método Estudo transversal, realizado com 419 idosos de 72 anos ou mais, entre 2016 e 2017. Os participantes são provenientes do estudo de seguimento do Estudo FIBRA, que incluiu idosos não institucionalizados residentes da zona urbana dos municípios de Campinas e Ermelino Matarazzo, do estado de São Paulo, Brasil. A variável mediadora foi dor crônica, avaliada positivamente pelo autorrelato da presença de dor nos últimos seis meses. As variáveis independentes contempladas foram: sociodemográficas, comportamentos relacionados à saúde, multimorbidade, sintomas depressivos, insônia e autoavaliação de saúde. As relações diretas e indiretas foram testadas por meio da análise de caminhos. Resultados 57,0% da população estudada relatou dor crônica. O sexo feminino, o Índice de Massa Corporal (IMC) elevado, a multimorbidade e os sintomas de insônia e de depressão apresentaram associação direta com dor crônica. A dor crônica figurou como variável mediadora das associações entre autoavaliação de saúde e gênero, IMC, multimorbidade e sintomas de insônia. Conclusão Os dados mostram uma rede de interações da dor crônica com variáveis sociodemográficas e de condições de saúde. Esse conhecimento poderá beneficiar o manejo e o cuidado à pessoa idosa acometida por dor crônica.

Multimorbidity, frailty and functional disability in octogenarians: A structural equation analysis of relationship

Path analysis allows for an understanding of the complex interrelationships between multiple variables and interactions in the octogenarians. The aim of this study was to estimate the isolated and combined prevalence of multimorbidity, frailty and functional disability and the direct and indirect association of these conditions in octogenarians. A cross-sectional study was conducted with 166 community-dwelling individuals aged 80 years or older participating in the FIBRA80+ epidemiological study. Multimorbidity was defined by three or more chronic diseases, frailty according to 3 or more components of physical frailty phenotype and functional disability as aid needed to perform one or more activities of daily living (ADLs). Associations were tested by Pearson's chi-square test; the relationship between the variables of interest and the mediating variables was tested with structural equation (path) analysis. We observed a higher prevalence of seniors with disability and multimordibity/disability. In path analysis, number of chronic diseases mediated the relation between sex and number of frailty components (p = 0.031), and these mediated the relation between number of diseases and disability (p = 0.008). The study points out the relationship between the simultaneous presence and interaction between multimorbidity, functional disability and frailty. Through path analysis, our findings provide characteristics in relation to the health-disease process, mainly mediation and interaction among octogenarians.

Limited formal education is strongly associated with lower cognitive status, functional disability and frailty status in older adults

Limited formal education is still common in ageing populations. Although limited formal education seems to be independently and negatively associated with cognition, functional abilities and frailty in ageing, no studies have examined whether the gradient of limited formal education has an impact on health in later life.

Cognitive screening test in primary care: cut points for low education

OBJECTIVE

To establish the diagnostic accuracy of the Brazilian version of the General Practitioner Assessment of Cognition (GPCOG-Br) compared to the Mini-Mental State Examination (MMSE) in individuals with low educational level.

METHODS

Ninety-three patients (≥ 60 years old) from Brazilian primary care units provided sociodemographic, cognitive, and functional data. Receiver operating characteristics, areas under the curve (AUC) and logistic regressions were conducted.

RESULTS

Sixty-eight patients with 0-4 years of education. Cases (n = 44) were older (p = 0.006) and performed worse than controls (n = 49) on all cognitive or functional measures (p < 0.001). The GPCOG-Br demonstrated similar diagnostic accuracy to the MMSE (AUC = 0.90 and 0.91, respectively) and similar positive and negative predictive values (PPV/NPV, respectively: 0.79/0.86 for GPCOG-Br and 0.79/0.81 for MMSE). Adjusted cut-points displayed high sensitivity (all 86%) and satisfactory specificity (65%-80%). Lower educational level predicted lower cognitive performance.

CONCLUSIONS

The GPCOG-Br is clinically well-suited for use in primary care.

Impact of hypertension severity on arterial stiffness, cerebral vasoreactivity, and cognitive performance

Aging, hypertension (HTN), and other cardiovascular risk factors contribute to structural and functional changes of the arterial wall.

Verbal fluency in elderly with and without hypertension and diabetes from the FIBRA study in Ermelino Matarazzo

BACKGROUND

There are few studies on the qualitative variables derived from the animal category verbal fluency test (VF), especially with data originating from low-income samples of community-based studies.

OBJECTIVE

To compare elderly with and without hypertension (HTN) and diabetes mellitus (DM) regarding the total number of animals spoken, number of categories, groups and category switches on the VF test.

METHODS

We used the database of the FIBRA (Frailty in Brazilian Elderly) community-based study. The variables number of Categories, Groups and Category Switches were created for each participant. The total sample (n = 384) was divided into groups of elderly who reported having HTN, DM, both HTN and DM, or neither of these conditions.

RESULTS

There were no significant differences between the groups with and without these chronic diseases for VF total score or for the qualitative variables.

CONCLUSION

Among independent community-dwelling elderly, the qualitative variables derived from the VF animal category may not add information regarding the cognitive profile of elderly with chronic diseases. Total VF score and the qualitative variables Category, Group and Switching did not differentiate elderly with and without HTN and DM.

Frailty criteria and cognitive performance are related: data from the FIBRA study in Ermelino Matarazzo, São Paulo, Brazil

OBJECTIVES

To assess the relationship between the CHS frailty criteria (Fried et al., 2001) and cognitive performance.

DESIGN

Cross sectional and population-based.

SETTING

Ermelino Matarazzo, a poor sub district of the city of São Paulo, Brazil.

PARTICIPANTS

384 community dwelling older adults, 65 and older.

MEASUREMENTS

Assessment of the CHS frailty criteria, the Brief Cognitive Screening Battery (memorization of 10 black and white pictures, verbal fluency animal category, and the Clock Drawing Test) and the Mini-Mental State Examination (MMSE).

RESULTS

Frail older adults performed significantly lower than non-frail and pre frail elderly in most cognitive variables. Grip strength and age were associated to MMSE performance, age was associated to delayed memory recall, gait speed was associated to verbal fluency and CDT performance, and education was associated to CDT performance.

CONCLUSION

Being frail may be associated with cognitive decline, thus, gerontological assessments and interventions should consider that these forms of vulnerability may occur simultaneously.