Mid-life sleep is associated with cognitive performance later in life in aging American Indians: data from the Strong Heart Study.

Background: Sleep-related disorders have been associated with cognitive decline and neurodegeneration. American Indians are at increased risk for dementia. Here, we aim to characterize, for the first time, the associations between sleep characteristics and subsequent cognitive performance in a sample of aging American Indians. Methods: We performed analyses on data collected in two ancillary studies from the Strong Heart Study, which occurred approximately 10 years apart with an overlapping sample of 160 American Indians (mean age at follow-up 73.1, standard deviation 5.6; 69.3% female and 80% with high school completion). Sleep measures were derived by polysomnography and self-reported questionnaires, including sleep timing and duration, sleep latency, sleep stages, indices of sleep-disordered breathing, and self-report assessments of poor sleep and daytime sleepiness. Cognitive assessment included measures of general cognition, processing speed, episodic verbal learning, short and long-delay recall, recognition, and phonemic fluency. We performed correlation analyses between sleep and cognitive measures. For correlated variables, we conducted separate linear regressions. We analyzed the degree to which cognitive impairment, defined as more than 1.5 standard deviations below the average Modified Mini Mental State Test score, is predicted by sleep characteristics. All regression analyses were adjusted for age, sex, years of education, body mass index, study site, depressive symptoms score, difference in age from baseline to follow-up, alcohol use, and presence of APOE e4 allele. Results: We found that objective sleep characteristics measured by polysomnography, but not subjective sleep characteristics, were associated with cognitive performance approximately 10 years later. Longer sleep latency was associated with worse phonemic fluency (ß = -0.069, p = 0.019) and increased likelihood of being classified in the cognitive impairment group later in life (odds ratio 1.037, p = 0.004). Longer duration with oxygen saturation < 90% was associated with better immediate verbal memory, and higher oxygen saturation with worse total learning, short and long-delay recall, and processing speed. Conclusion: In a sample of American Indians, sleep characteristics in midlife were correlated with cognitive performance a decade later. Sleep disorders may be modifiable risk factors for cognitive impairment and dementia later in life, and suitable candidates for interventions aimed at preventing neurodegenerative disease development and progression.

Barriers and Facilitators of Self-Management in Older People with Type 1 Diabetes: A Narrative Review Focusing on Cognitive Impairment.

Over the past decades, life expectancy of people with type 1 diabetes has increased considerably, which brings potential challenges due to the process of aging. Cognitive aging and dementia, as well as reductions in visual acuity, hearing and dexterity, can influence the frequency and quality of daily self-management activities, including medication taking and insulin dosing, glucose self-monitoring, and healthy eating. This can increase the risk for hypo- and hyperglycemic events, which, in turn, may contribute to cognitive decline. Because there is a gap in understanding the barriers and facilitators of self-management in older adults with type 1 diabetes and the relationship to cognitive functioning, the authors 1) review the available literature on cognitive aging and type 1 diabetes, 2) describe what self-management in later adulthood entails and the cognitive functions required for effective self-management behaviors, 3) analyze the interaction between type 1 diabetes, cognition, aging, and self-management behaviors, and 4) describe the barriers and facilitators for self-management throughout the life span and how they may differ for older people. Potential evidence-based practices that could be developed for older adults with type 1 diabetes are discussed. There is need for further studies that clarify the impact of aging on T1D self-management, ultimately to improve diabetes care and quality of life.

Culturally adapted cognitive assessment tool for Indigenous communities in Brazil: Content, construct, and criterion validity.

INTRODUCTION: Initial dementia prevalence estimates have revealed a significant burden of the disease in Indigenous communities in Amazonas, Brazil. However, the need for culturally adapted cognitive tools poses a critical challenge when assessing cognitive performance in these communities. This study addressed this issue by culturally adapting and providing validity indicators for the Brazilian Indigenous Cognitive Assessment (BRICA) tool in Manaus, Brazil's urban multiethnic Indigenous community. METHODS: Using a three-stage process and a stakeholder-engaged approach, the BRICA tool was culturally adapted in an urban multiethnic Indigenous community from Manaus, Brazil. The content validity index (CVI) examined inter-rater concordance between experts, while criterion and concurrent validity were performed using diagnostic consensus criteria in 141 Indigenous participants aged ≥ 50 years. RESULTS: Findings showed evidence of content validity in terms of equivalence aspects (scale CVI [S-CVI] 0.93) and relevance ratings (S-CVI 0.85) between expert panels. The identified cut-off score of ≤ 33/39 on the BRICA demonstrated a sensitivity of 94.4%, specificity of 99.2%, positive predictive value of 94.4%, and negative predictive value of 99.2% for dementia diagnosis. DISCUSSION: Using a stakeholder-engaged approach, we culturally adapted the BRICA tool for a Brazilian urban multiethnic Indigenous community. This comprehensive adaptation process resulted in favorable indicators of content, construct, and criteria validity for the BRICA tool. By addressing the existing bias in cognitive assessment within Indigenous communities, the BRICA tool represents a noteworthy breakthrough. Its implementation exhibits potential for improving the early detection and management of dementia among Indigenous groups. Highlights: Culturally sensitive tools are essential to assess cognition in Indigenous populations.An expert panel and stakeholders' perspectives were incorporated to design the Brazilian Indigenous Cognitive Assessment (BRICA) tool.A cognitive screening tool was adapted and validated using a stakeholder approach.BRICA is the first culturally sensitive cognitive tool for urban Brazilian Indigenous individuals.

Risk factors associated with cognitive performance and cognitive impairment in older adults with type 1 diabetes: Data from the Wireless Innovation for Seniors with Diabetes Mellitus (WISDM) study.

BACKGROUND: Adults with type 1 diabetes (T1D) are considered at increased risk for cognitive impairment and accelerated brain aging. However, longitudinal data on cognitive impairment and dementia in this population are scarce. OBJECTIVE: To identify risk factors associated with cognitive performance and cognitive impairment in a longitudinal sample of older adults with T1D. METHODS: We analyzed data collected as part of the Wireless Innovation for Seniors with Diabetes Mellitus (WISDM) Study, in which 22 endocrinology practices participated. Randomized participants with T1D ≥60 years of age who completed at least one cognitive assessment were included in this study (n = 203). Cognitive impairment was classified using published recommendations. RESULTS: Older age, male sex, non-private health insurance, worse daily functioning, diagnosis of neuropathy, and longer duration of diabetes were associated with worse cognitive performance, but not cognitive impairment. 49 % and 39 % of the sample met criteria for cognitive impairment at baseline and 52 weeks respectively. Of the participants that had data at both time points, 10 % were normal at baseline and impaired at 52 weeks and 22 % of participants (44 % of those classified with cognitive impairment at baseline) reverted to normal over 52 weeks. CONCLUSION: This study indicated that several demographic and clinical characteristics are associated with worse cognitive performance in older adults with T1D, but there were no associations between these characteristics and cognitive impairment defined by NIH Toolbox cognitive impairment criteria. Caution is warranted when assessing cognition in older adults with T1D, as a large percentage of those identified as having cognitive impairment at baseline reverted to normal after 52 weeks. There is need for future studies on the interrelationship of cognition and aging to better understand the effects of T1D on cognitive health, to improve clinical monitoring and help mitigate the risk of dementia in this population.

Usefulness of the Montreal Cognitive Assessment in Older Adults With Type 1 Diabetes.

Objective: Older adults with type 1 diabetes are at high risk for cognitive impairment, yet the usefulness of common cognitive screening instruments has not been evaluated in this population. Methods: A total of 201 adults ≥60 years of age with type 1 diabetes completed a battery of neuropsychological measures and the Montreal Cognitive Assessment (MoCA). Receiver operating characteristic (ROC) curves and Youden indices were used to evaluate overall screening test performance and to select an optimal MoCA cutoff score for detecting low cognitive performance, as defined as two or more neuropsychological test performances ≥1.5 SD below demographically corrected normative data. Results: The ROC area under the curve (AUC) was 0.745 (P < 0.001). The publisher-recommended cutoff score of <26 resulted in sensitivity of 60.4% and specificity of 71.4%, whereas a cutoff score of <27 resulted in sensitivity of 75.0% and specificity of 61.0%. The Youden indices for these cutoff scores were 0.318 and 0.360, respectively. Minimally acceptable sensitivity (i.e., >0.80) was obtained when using a cutoff score of <28, whereas >0.80 specificity was obtained with a cutoff score of <25. Conclusions: The MoCA has modest overall performance (AUC 0.745) as a cognitive screening instrument in older adults with type 1 diabetes. The standard cutoff score of <26/30 may not adequately detect individuals with neuropsychological testing-defined abnormal cognition. The optimal MoCA cutoff score (based on the Youden index) was <27/30. A score of <28 resulted in acceptable sensitivity but was accompanied by low specificity (42%). Future studies with a more diverse population are needed to confirm these findings.

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.

Associations between Intra-Individual Neurocognitive Variability and Prospective Memory in Veterans with Mild Traumatic Brain Injury History and Posttraumatic Stress Disorder.

OBJECTIVE: Mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) frequently co-occur and are associated with neurocognitive intra-individual variability (IIV) and difficulty with prospective memory (PM). The current study aimed to examine associations between IIV and PM in this comorbid group. METHOD: Fifty veterans with a history of blast mTBI and current comorbid PTSD completed a standardized neurocognitive battery to measure IIV, and the Memory for Intentions Screening Test measuring PM. RESULTS: Adjusting for age, education, and race, higher IIV was associated with poorer time-based PM (p < .001, f2 = .34), but not event-based PM. In a subset of the sample with self-report data, higher IIV was associated with poorer self-reported retrospective memory, but not PM. CONCLUSIONS: Cognitive variability on a standardized neuropsychological battery was associated with strategically demanding PM, which is an ecologically relevant ability and highlights the possible connection between subtle cognitive difficulties in-clinic and those experienced in daily life.

Neuropsychiatric Symptoms of Alzheimer's Disease in Down Syndrome and Its Impact on Caregiver Distress.

BACKGROUND: Neuropsychiatric symptoms (NPS) are non-cognitive manifestations common to dementia and other medical conditions, with important consequences for the patient, caregivers, and society. Studies investigating NPS in individuals with Down syndrome (DS) and dementia are scarce. OBJECTIVE: Characterize NPS and caregiver distress among adults with DS using the Neuropsychiatric Inventory (NPI). METHODS: We evaluated 92 individuals with DS (≥30 years of age), divided by clinical diagnosis: stable cognition, prodromal dementia, and AD. Diagnosis was determined by a psychiatrist using the Cambridge Examination for Mental Disorders of Older People with Down's Syndrome and Others with Intellectual Disabilities (CAMDEX-DS). NPS and caregiver distress were evaluated by an independent psychiatrist using the NPI, and participants underwent a neuropsychological assessment with Cambridge Cognitive Examination (CAMCOG-DS). RESULTS: Symptom severity differed between-groups for delusion, agitation, apathy, aberrant motor behavior, nighttime behavior disturbance, and total NPI scores, with NPS total score being found to be a predictor of AD in comparison to stable cognition (OR for one-point increase in the NPI = 1.342, p = 0.012). Agitation, apathy, nighttime behavior disturbances, and total NPI were associated with CAMCOG-DS, and 62% of caregivers of individuals with AD reported severe distress related to NPS. Caregiver distress was most impacted by symptoms of apathy followed by nighttime behavior, appetite/eating abnormalities, anxiety, irritability, disinhibition, and depression (R2 = 0.627, F(15,76) = 8.510, p < 0.001). CONCLUSION: NPS are frequent and severe in individuals with DS and AD, contributing to caregiver distress. NPS in DS must be considered of critical relevance demanding management and treatment. Further studies are warranted to understand the biological underpinnings of such symptoms.

Construct validity, ecological validity and acceptance of self-administered online neuropsychological assessment in adults.

Objective: The goal of this project was to explore the initial psychometric properties (construct and ecological validity) of self-administered online (SAO) neuropsychological assessment (using the www.testmybrain.org platform), compared to traditional testing, in a clinical sample, as well as to evaluate participant acceptance. SAO assessment has the potential to expand the reach of in-person neuropsychological assessment approaches.Method: Counterbalanced, within-subjects design comparing SAO performance to in-person performance in adults with diabetes with and without Chronic Kidney Disease (CKD). Forty-nine participants completed both assessment modalities (type 1 diabetes N = 14, type 2 diabetes N = 35; CKD N = 18).Results: Associations between SAO and analogous in-person tests were adequate to good (r = 0.49-0.66). Association strength between divergent cognitive tests did not differ between SAO versus in-person tests. SAO testing was more strongly associated with age than in-person testing (age R2=0.54 versus 0.23), while prediction of education, HbA1c, and estimated glomerular filtration rate (eGFR) did not differ significantly between test modalities (education R2=0.37 versus 0.30; HbA1c R2=0.20 versus 0.12; eGFR R2 = 0.41 versus 0.33). Associations with measures of everyday functioning were also similar (Functional Activities Questionnaire R2=0.08 versus 0.07; Neuro-QoL R2=0.14 versus 0.16; Diabetes Self-Management Questionnaire R2=0.19 versus 0.19).Conclusions: The selected SAO neuropsychological tests had acceptable construct validity (including divergent, convergent, and criterion-related validity), and similar ecological validity to that of traditional testing. These SAO assessments were acceptable to participants and appear appropriate for use in research applications, although further research is needed to better understand the strengths and weaknesses in other clinical populations.

Frontal-subcortical behaviors during Alzheimer's disease in individuals with Down syndrome.

There is evidence that frontal-subcortical circuits play an important role in the initial presentation of dementia in Down syndrome (DS), including changes in behavior, a decline in working memory and executive dysfunction. We evaluated 92 individuals with DS (≥30 years of age), divided into 3 groups by diagnosis-stable cognition, prodromal dementia, and Alzheimer's disease. Each individual was evaluated with an executive protocol developed for people with intellectual disabilities and was rated for behaviors related to frontal lobe dysfunction (disinhibition, executive dysfunction, and apathy) by an informant using the Frontal Systems Behavior Scale. Informant-reported behaviors related to frontal lobe dysfunction were found to correlate negatively with executive function performance. Disinhibition and executive dysfunction were associated with the clinical stage of dementia. The odds of having Alzheimer's disease increased in parallel with increases in the domain and total Frontal Systems Behavior Scale scores (p ≤ 0.5). Disinhibition, executive dysfunction and apathy should be taken into consideration during the clinical evaluation of adults with DS, and future studies should consider the intersection of neuropathology, brain connectivity, and behavior.

Neuroimaging and other modalities to assess Alzheimer's disease in Down syndrome.

People with Down syndrome (DS) develop Alzheimer's disease (AD) at higher rates and a younger age of onset compared to the general population. As the average lifespan of people with DS is increasing, AD is becoming an important health concern in this group. Neuroimaging is becoming an increasingly useful tool in understanding the pathogenesis of dementia development in relation to clinical symptoms. Furthermore, neuroimaging has the potential to play a role in AD diagnosis and monitoring of therapeutics. This review describes major recent findings from in vivo neuroimaging studies analysing DS and AD via ligand-based positron emission tomography (PET), [18F] fluorodeoxyglucose (FDG)-PET, structural magnetic resonance imaging (sMRI), and diffusion tensor imaging (DTI). Electroencephalography (EEG) and retinal imaging are also discussed as emerging modalities. The review is organized by neuroimaging method and assesses the relationship between cognitive decline and neuroimaging changes. We find that amyloid accumulation seen on PET occurs prior to dementia onset, possibly as a precursor to the atrophy and white matter changes seen in MRI studies. Future PET studies relating tau distribution to clinical symptoms will provide further insight into the role this protein plays in dementia development. Brain activity changes demonstrated by EEG and metabolic changes seen via FDG-PET may also follow predictable patterns that can help track dementia progression. Finally, newer approaches such as retinal imaging will hopefully overcome some of the limitations of neuroimaging and allow for detection of dementia at an earlier stage.

Frontal Lobe Degeneration in Adults with Down Syndrome and Alzheimer's Disease: A Review.

BACKGROUND: There is a proven link between Down syndrome and the early development of the neuropathological features of Alzheimer's disease (AD). Changes in the personality and behavior of adults with Down syndrome might indicate the early stages of dementia or of frontotemporal lobar degeneration. The objective of this study was to investigate the executive functions and changes in behavior associated with frontal lobe degeneration in individuals with Down syndrome who develop AD. We conducted a systematic review selecting studies employing cognitive assessments. SUMMARY: We identified few studies using objective measurements to determine whether cognitive aspects associated with the frontal lobe correlate with dementia in this population. We observed a tendency toward such correlations. KEY MESSAGES: There is a need for further studies in which objective measures of cognitive and behavioral factors are evaluated together with data related to brain function and morphology.

Cognitive Rehabilitation of Dementia in Adults with Down Syndrome: A Review of Non-Pharmacological Interventions.

BACKGROUND: There is a close genetic relationship between Alzheimer's disease (AD) and Down syndrome (DS), AD being the most severe mental disorder affecting ageing individuals with DS. The objective of the present study was to evaluate the efficacy of cognitive rehabilitation interventions in DS patients with AD by means of a critical literature review. SUMMARY: Because AD is progressive and irreversible, treatment is aimed at delaying and reducing the cognitive and functional decline in order to preserve or improve quality of life. The effects that pharmacological treatments and cognitive interventions have on elderly individuals with AD are well documented. Recent clinical trials have investigated the use of pharmacological treatment in DS patients with AD, generating preliminary results that have been unfavourable. KEY MESSAGES: There is a clear lack of studies addressing the efficacy of cognitive rehabilitation interventions in DS patients with AD, and there is an urgent need for studies providing evidence to inform decisions regarding the appropriate choice of treatment strategies.

Bereavement and behavioral changes as risk factors for cognitive decline in adults with Down syndrome.

BACKGROUND: Cognitive decline and Alzheimer's disease often affect older adults with Down syndrome (DS) much earlier than those in the general population. There is also growing evidence of the effects of negative life events on the mental health and behavior of individuals with intellectual disability. However, to our knowledge, this is the first study investigating objective cognitive decline following bereavement in aging individuals with DS. OBJECTIVE: The objective of this study was to determine whether cognitive decline correlates with bereavement following the recent loss of a caregiver or with behavioral changes in a sample of adult individuals with DS who do not meet the criteria for dementia or depression, using the longitudinal assessment of the Cambridge Cognitive Examination (CAMCOG), together with the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). METHODS: We evaluated 18 subjects at baseline and over a follow-up period of 14-22 months, attempting to determine whether cognitive decline correlates with bereavement following the recent loss of the main caregiver or with behavioral changes (as assessed with the Neuropsychiatric Inventory). RESULTS: The mean rate of change in CAMCOG was -1.83 (standard deviation 4.51). Behavioral changes had a significant direct influence on cognitive decline. When bereavement was accompanied by behavioral changes, the probability of cognitive decline was 87% (odds ratio 3.82). CONCLUSION: The occurrence of behavioral changes attributed to bereavement following the loss of the primary caregiver significantly increases the probability of cognitive decline in individuals with DS. Longitudinal comparison of the CAMCOG and use of the IQCODE appear to enrich the analysis of cognitive decline in individuals with DS. Further studies involving larger samples are needed in order to corroborate and expand upon our findings, which can have implications for the clinical management of older adults with DS.

The emergence of thanatology and current practice in death education.

Thanatology is a recent field that contemplates death studies and employs an interdisciplinary approach to practice. This science emerged in a historical context marked by intense social, economic, and political changes that contributed to the concept of death being excluded from social life. This literature review aims to outline the history and evolution ofthanatology in Western society, delineating the contextual circumstances that led to its origin and drawing special attention to current works on death education. In our post-modern society, the call for studies in the field of thanatology appears to be increasing. However, although there have been significant contributions and promising research is underway, there are still many questions to be answered.