Cognitive impairment in the U.S.: Lifetime risk, age at onset, and years impaired

Genetic architecture of epigenetic cortical clock age in brain tissue from older individuals: alterations in CD46 and other loci

The cortical epigenetic clock was developed in brain tissue as a biomarker of brain aging. As one way to identify mechanisms underlying aging, we conducted a GWAS of cortical age. We leveraged postmortem cortex tissue and genotyping array data from 694 participants of the Rush Memory and Aging Project and Religious Orders Study (ROSMAP; 11000,000 SNPs), and meta-analysed ROSMAP with 522 participants of Brains for Dementia Research (5,000,000 overlapping SNPs). We confirmed results using eQTL (cortical bulk and single nucleus gene expression), cortical protein levels (ROSMAP), and phenome-wide association studies (clinical/neuropathologic phenotypes, ROSMAP). In the meta-analysis, the strongest association was rs4244620 (p = 1.29 × 10-7), which also exhibited FDR-significant cis-eQTL effects for CD46 in bulk and single nucleus (microglia, astrocyte, oligodendrocyte, neuron) cortical gene expression. Additionally, rs4244620 was nominally associated with lower cognition, faster slopes of cognitive decline, and greater Parkinsonian signs (n ~ 1700 ROSMAP with SNP/phenotypic data; all p ≤ 0.04). In ROSMAP alone, the top SNP was rs4721030 (p = 8.64 × 10-8) annotated to TMEM106B and THSD7A. Further, in ROSMAP (n = 849), TMEM106B and THSD7A protein levels in cortex were related to many phenotypes, including greater AD pathology and lower cognition (all p ≤ 0.0007). Overall, we identified converging evidence of CD46 and possibly TMEM106B/THSD7A for potential roles in cortical epigenetic clock age.

Facilitation of working memory capacity by transcranial direct current stimulation: a secondary analysis from the augmenting cognitive training in older adults (ACT) study

Aging is a public health concern with an ever-increasing magnitude worldwide. An array of neuroscience-based approaches like transcranial direct current stimulation (tDCS) and cognitive training have garnered attention in the last decades to ameliorate the effects of cognitive aging in older adults. This study evaluated the effects of 3 months of bilateral tDCS over the frontal cortices with multimodal cognitive training on working memory capacity. Two hundred ninety-two older adults without dementia were allocated to active or sham tDCS paired with cognitive training. These participants received repeated sessions of bilateral tDCS over the bilateral frontal cortices, combined with multimodal cognitive training. Working memory capacity was assessed with the digit span forward, backward, and sequencing tests. No baseline differences between active and sham groups were observed. Multiple linear regressions indicated more improvement of the longest digit span backward from baseline to post-intervention (p = 0.021) and a trend towards greater improvement (p = 0.056) of the longest digit span backward from baseline to 1 year in the active tDCS group. No significant between-group changes were observed for digit span forward or digit span sequencing. The present results provide evidence for the potential for tDCS paired with cognitive training to remediate age-related declines in working memory capacity. These findings are sourced from secondary outcomes in a large randomized clinical trial and thus deserve future targeted investigation in older adult populations.

Aging in isolation: Sexual orientation differences in navigating cognitive decline

Introduction

Subjective cognitive decline is a self-reported measure of worsening memory and day-to-day decision making. Cognitive decline may impair an individual's ability to complete instrumental activities of daily living (IADL) such as preparing meals or taking medication, ultimately limiting one's ability to live independently. People with IADL impairments typically rely on informal care from spouses or children. Interpersonal and structural discrimination towards sexual minority (SM, including lesbian, gay, bisexual, and other queer identified) populations may contribute to disparities in cognitive decline and informal care outcomes.

Objective

Estimate differences in prevalence, severity, and receipt of social support for subjective cognitive decline stratified by sex and SM status.

Methods

Cross-sectional study design using a probability sample (n = 172,047) from the Behavioral Risk Factor Surveillance System 2015-2019. Prevalence estimates and multivariable Poisson regression models were used to compare outcomes by sex and sexual identity.

Results

Compared to heterosexual peers, SM men and women were more likely to experience cognitive decline (15% of SM men, 11% of heterosexual men, 17% of SM women, 11% of heterosexual women). In adjusted models, SM women were 22% more likely (95%CI:3%-44%, p < .05) to report IADL impairments due to cognitive decline but were 17% less likely (95%CI:1%-31%, p < .05) to receive any social support with IADL impairments compared to heterosexual women. In adjusted models, SM men were 25% more likely (95%CI: 0%-56%, p < .05) to report IADL impairments due to cognitive decline but reported no significant difference in receiving social support with IADL impairments compared to heterosexual men.

Discussion

We identified significant unmet need for social supports for IADL impairments, with highest unmet need among SM women. Comprehensive strategies such as LGBTQ + affirming assisted living and home and community-based services are needed to ensure equity in receipt of long-term supports and services for SM populations.

Story Recall in Peer Conflict Resolution Discourse Task to Identify Older Adults Testing Within Range of Cognitive Impairment

PURPOSE

The current study used behavioral measures of discourse complexity and story recall accuracy in an expository discourse task to distinguish older adults testing within range of cognitive impairment according to a standardized cognitive screening tool in a sample of self-reported healthy older adults.

METHOD

Seventy-three older adults who self-identified as healthy completed an expository discourse task and neuropsychological screener. Discourse data were used to classify participants testing within range of cognitive impairment using multiple machine learning algorithms and stability analysis for identifying reliably predictive features in an effort to maximize prediction accuracy. We hypothesized that a higher rate of pronoun use and lower scores on story recall would best classify older adults testing within range of cognitive impairment.

RESULTS

The highest classification accuracy exploited a single variable in a remarkably intuitive way: using 66% story recall as a cutoff for cognitive impairment. Forcing this decision tree model to use more features or increasing its complexity did not improve accuracy. Permutation testing confirmed that the 77% accuracy and 0.18 Brier skill score achieved by the model were statistically significant (p < .00001).

CONCLUSIONS

These results suggest that expository discourse tasks that place demands on executive functions, such as working memory, can be used to identify aging adults who test within range of cognitive impairment. Accurate representation of story elements in working memory is critical for coherent discourse. Our simple yet highly accurate predictive model of expository discourse provides a promising assessment for easy identification of cognitive impairment in older adults.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26543824.

Age-Related Hearing Loss, Cognitive Decline, and Social Interaction: Testing a Framework

PURPOSE

Aging increases risk for hearing loss, cognitive decline, and social isolation; however, the nature of their interconnection remains unclear. This study examined the interplay between age-related hearing loss, cognitive decline, and social isolation in adults by testing the ability to understand speech in background noise, a challenge frequently reported by many older adults.

METHOD

We analyzed data collected from 128 adults (20-79 years of age, Mage = 51 years) recruited as part of the Aging Brain Cohort at the University of South Carolina repository. The participants underwent testing for hearing, cognition, and social interaction, which included pure-tone audiometry, a words-in-noise (WIN) test, a hearing questionnaire (Speech, Spatial and Qualities of Hearing Scale [SSQ12]), a social questionnaire (Patient-Reported Outcomes Measurement Information System-57 Social), and the Montreal Cognitive Assessment. We used a single pure-tone average (PTA) threshold value and a single WIN threshold value for each participant because there were no differences on average between the left and right ears.

RESULTS

Poorer hearing was significantly associated with cognitive decline, through both PTA and WIN thresholds, with a stronger association observed for WIN threshold. Adults with poorer hearing also exhibited greater social isolation, as evidenced by their WIN threshold and SSQ12 score, although not through PTA. This connection was more pronounced with the WIN threshold than with the SSQ12 score. Cognition was not related to social isolation, suggesting that social isolation is affected more by the ability to understand words in noise than by cognition in a nondemented population.

CONCLUSIONS

Understanding speech in challenging auditory environments rather than mere threshold detection is strongly linked to social isolation and cognitive decline. Thus, inclusion of a word-recognition-in-noise test and a social isolation survey in clinical settings is warranted.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26237060.

Foreclosure, memory decline, and dementia probability: A longitudinal cohort study

INTRODUCTION

Housing insecurity is rising among older adults; health researchers know little about how this may impact their cognitive health. We investigated links between foreclosure and older adults' memory and probability of dementia.

METHODS

Using the Health and Retirement Study (2008 to 2018), we fit mixed models comparing the memory and dementia probability scores of 249 older adults who experienced foreclosure (treated) with 15,645 who did not. Baseline covariates included sociodemographics, health, and cognition. Models were stratified by age group.

RESULTS

Foreclosure was associated with faster memory decline among middle-aged (50 to 64) older adults (-0.007 standard deviations/year, 95% confidence interval: -0.13, -0.001). Compared to average memory decline among middle-aged older adults who were stably housed, foreclosure equated to 3.7 additional years of aging over 10 years. Among those 65+, differences between those who were and were not foreclosed upon were short-lived and less clear, potentially driven by depletion-of-susceptibles bias.

DISCUSSION

Foreclosure may endanger older adults' memory.

HIGHLIGHTS

Housing instability is a key determinant of cognitive aging. We examined foreclosure and levels and changes in memory and dementia probability scores in the US older adult population. Foreclosure was associated with faster memory decline among middle-aged (50 to 64) older adults, equivalent to 3.7 additional years of cognitive aging over 10 years. Foreclosure yielded sharp memory declines and increases in dementia probability among older adults 65 and above. Foreclosure imposes a greater risk for older adults' cognitive decline.

Exposome-wide association study of cognition among older adults in the National Health and Nutrition Examination Survey

Cognitive impairment among older adults is a growing public health challenge and environmental chemicals may be modifiable risk factors. A wide array of chemicals has not yet been tested for association with cognition in an environment-wide association framework. In the US National Health and Nutrition Examination Survey (NHANES) 1999-2000 and 2011-2014 cross-sectional cycles, cognition was assessed using the Digit Symbol Substitution Test (DSST, scores 0-117) among participants aged 60 years and older. Concentrations of environmental chemicals measured in blood or urine were log2 transformed and standardized. Chemicals with at least 50% of measures above the lower limit of detection were included (nchemicals=147, nclasses=14). We tested for associations between chemical concentrations and cognition using parallel survey-weighted multivariable linear regression models adjusted for age, sex, race/ethnicity, education, smoking status, fish consumption, cycle year, urinary creatinine, and cotinine. Participants with at least one chemical measurement (n=4,982) were mean age 69.8 years, 55.0% female, 78.2% non-Hispanic White, and 77.0% at least high school educated. The mean DSST score was 50.4 (standard deviation (SD)=17.4). In adjusted analyses, 5 of 147 exposures were associated with DSST at p-value<0.01. Notably, a SD increase in log2-scaled cotinine concentration was associated with 2.71 points lower DSST score (95% CI -3.69, -1.73). A SD increase in log2-scaled urinary tungsten concentration was associated with 1.34 points lower DSST score (95% CI -2.11, -0.56). Exposure to environmental chemicals, particularly heavy metals and tobacco smoke, may be modifiable factors for cognition among older adults.

Neurocognitive profiles are associated with subsequent brain integrity in a sample of Hispanics/Latinos: Findings from the SOL-INCA-MRI study (HCHS/SOL)

The Hispanic/Latino population is one of the largest and most diverse ethnoracial groups in the United States at high risk for dementia. We examined cognitive constructs and associations with subsequent hippocampal volume (HV) and white matter hyperintensity volume (WMHV). Participants were from the Hispanic Community Health Study/Study of Latinos-Magnetic Resonance Imaging Study (n = 2029). We examined confirmatory factor analysis and longitudinal invariance using neurocognitive scores at Visits 1 (2008-2011) and 2 (2014-2018) and path analyses. We obtained a longitudinally invariant two-factor episodic memory (EM) and working memory (WM) construct. Lower EM profile at both visits was associated with greater WMHV and smaller HV at Visit 2. Lower WM profile at both visits was associated with larger WMHV and smaller HV at Visit 2. Neurocognitive profiles were associated with subsequent neurodegeneration in a sample of Hispanics/Latinos. Identifying neurocognitive risk profiles may lead to early detection and intervention, and significantly impact the course of neurodegeneration.

Highlights

Cognitive profiles predict brain integrity up to 10 years later.We observed two-factor latent memory constructs and longitudinal invariance.These findings were observed in a Hispanic/Latino cohort.

Cognitive Impairment in the Primary Care Clinic

Cognitive impairment is a common problem in the geriatric population and is characterized by variable symptoms of memory difficulties, executive dysfunction, language or visuospatial problems, and behavioral changes. It is imperative that primary care clinicians recognize and differentiate the variable symptoms associated with cognitive impairment from changes attributable to normal aging or secondary to other medical conditions. A thorough evaluation for potentially reversible causes of dementia is required before diagnosis with a neurodegenerative dementia. Other abnormal neurologic findings, rapid progression, or early age of onset are red flags that merit referral to neurology for more specialized evaluation and treatment.

Assessment of Cognitive Function in European Adults Aged 50+in Relation to Their Handgrip Strength and Physical Inactivity: The SHARE Study During 2019-2020

BACKGROUND

Cognitive function is crucial during aging. This study assessed the cognitive function of European adults aged 50 and over in relation to handgrip strength and physical inactivity. Study Design: This was a cross-sectional survey.

METHODS

Data were collected from 41,395 adults from 27 European countries participating in the Survey of Health, Ageing, and Retirement in Europe (SHARE) during 2019-2020. Cognitive function was assessed based on five tests, and cognitive impairment was defined using 3+tests. Handgrip strength and physical inactivity were also correlated through the analysis of covariance using a complex study design.

RESULTS

The majority of participants were female (56.6%), with a mean age of 70.9 years, and 22.6% presented multimorbidity. Furthermore, 51.1% had a normal cognitive function, while 13.3% had cognitive impairment (The estimated population was 21,944,722). Moreover, cognitive impairment was more prevalent in females than in males (14.4% vs. 12.0%, P<0.001) in patients with no years of education (P<0.001) and origin from southern European countries (P<0.001). Additionally, participants with cognitive impairment had lower mean handgrip strength compared to those with cognitive impairment in 1-2 criteria or with normal cognitive function (29.3 vs. 33.4 and 35.1 kg, respectively, P<0.001). Physically inactive participants had higher odds ratio (OR) of cognitive impairment than those engaging in moderate/vigorous physical activity, both in 1-2 tests (OR:1.73, 95% confidence interval (CI): 1.32-2.26) and in 3+tests (OR: 3.36, 95% CI: 2.57-4.40).

CONCLUSION

Cognitive impairment presented low prevalence and was associated with low levels of handgrip strength and physical inactivity. These specific factors may play a special role in early detection, diagnosis, and treatment or may slow down the progression of cognitive impairment.

The Association of Upper Airway Anatomy with Brain Structure: The Multi-Ethnic Study of Atherosclerosis

Sleep apnea, affecting an estimated 1 in 4 American adults, has been reported to be associated with both brain structural abnormality and impaired cognitive function. Obstructive sleep apnea is known to be affected by upper airway anatomy. To better understand the contribution of upper airway anatomy to pathways linking sleep apnea with impaired cognitive function, we investigated the association of upper airway anatomy with structural brain abnormalities. Based in the Multi-Ethnic Study of Atherosclerosis, a longitudinal cohort study of community-dwelling adults, a comprehensive sleep study and an MRI of the upper airway and brain were performed on 578 participants. Machine learning models were used to select from 74 upper airway measures those measures most associated with selected regional brain volumes and white matter hyperintensity volume. Linear regression assessed associations between the selected upper airway measures, sleep measures, and brain structure. Maxillary divergence was positively associated with hippocampus volume, and mandible length was negatively associated with total white and gray matter volume. Both coefficients were small (coefficients per standard deviation 0.063 mL, p = 0.04, and - 7.0 mL, p < 0.001 respectively), and not affected by adjustment for sleep study measures. Self-reported snoring >2 times per week was associated with larger hippocampus volume (coefficient 0.164 mL, p = 0.007), and higher percentage of time in the N3 sleep stage was associated with larger total white and gray matter volume (4.8 mL, p = 0.004). Despite associations of two upper airway anatomy measures with brain volume, the evidence did not suggest that these upper airway and brain structure associations were acting primarily through the pathway of sleep disturbance.

Multimorbid life expectancy across race, socio-economic status, and sex in South Africa

Multimorbidity is increasing globally as populations age. However, it is unclear how long individuals live with multimorbidity and how it varies by social and economic factors. We investigate this in South Africa, whose apartheid history further complicates race, socio-economic, and sex inequalities. We introduce the term 'multimorbid life expectancy' (MMLE) to describe the years lived with multimorbidity. Using data from the South African National Income Dynamics Study (2008-17) and incidence-based multistate Markov modelling, we find that females experience higher MMLE than males (17.3 vs 9.8 years), and this disparity is consistent across all race and education groups. MMLE is highest among Asian/Indian people and the post-secondary educated relative to other groups and lowest among African people. These findings suggest there are associations between structural inequalities and MMLE, highlighting the need for health-system and educational policies to be implemented in a way proportional to each group's level of need.

Amelioration of age-related cognitive decline and anxiety in mice by Centella asiatica extract varies by sex, dose and mode of administration

Background: A water extract (CAW) of the Ayurvedic plant Centella asiatica administered in drinking water has been shown to improve cognitive deficits in mouse models of aging and neurodegenerative diseases. Here the effects of CAW administered in drinking water or the diet on cognition, measures of anxiety and depression-like behavior in healthy aged mice are compared. Methods: Three- and eighteen-month-old male and female C57BL6 mice were administered rodent AIN-93M diet containing CAW (0, 0.2, 0.5 or 1% w/w) to provide 0, 200 mg/kg/d, 500 mg/kg/d or 1,000 mg/kg/d CAW for a total of 5 weeks. An additional group of eighteen-month-old mice were treated with CAW (10 mg/mL) in their drinking water CAW for a total of 5 weeks to deliver the same exposure of CAW as the highest dietary dose (1,000 mg/kg/d). CAW doses delivered were calculated based on food and water consumption measured in previous experiments. In the fourth and fifth weeks, mice underwent behavioral testing of cognition, anxiety and depression (n = 12 of each sex per treatment group in each test). Results: Aged mice of both sexes showed cognitive deficits relative to young mice while only female aged mice showed increased anxiety compared to the young female mice and no differences in depression were observed between the different ages. CAW (1,000 mg/kg/d) in the drinking water improved deficits in aged mice in learning, executive function and recognition memory in both sexes and attenuated the increased measures of anxiety observed in the aged female mice. However, CAW in the diet only improved executive function in aged mice at the highest dose (1,000 mg/kg/d) in both sexes and did so less robustly than when given in the water. There were no effects of CAW on depression-like behavior in aged animals regardless of whether it was administered in the diet or the water. Conclusions: These results suggest that CAW can ameliorate age-related changes in measures of anxiety and cognition and that the mode of administration is important for the effects of CAW on resilience to these age-related changes.

Seize the Data: An Analysis of Guardianship Annual Reports

Courts have a legal and ethical duty to monitor adult guardianship cases to protect the rights of individuals with guardians. Aging and disability advocates have been recommending improvements to adult guardianship monitoring for decades. The aim of this study is to examine annual guardianship reporting procedures in each state. Using the National Guardianship Association's (NGA) Standards of Practice as a guide, we summarize what is missing from adult guardianship annual report forms in each state. Since 2000, the NGA Standards have been the benchmark for guiding guardianship best practices, making it a valuable tool for guardianship reporting and monitoring. Results show that most states are not collecting thorough data on adults with guardians, their guardians, or the guardian-client relationship. Additionally, many existing annual report forms may be difficult to complete due to confusing question structure and reading levels that are above the national average, especially since most adult guardians are nonprofessional guardians. Improved reporting procedures would help courts monitor guardianships more effectively, ensure that the rights of individuals with guardians are being protected, and provide meaningful data on the overall state of guardianship. Limitations and plans for future research are also discussed.

Association between Flavonoid Intake and Cognitive Executive Function among African American and White Adults in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) Study

Healthy dietary patterns rich in flavonoids may benefit cognitive performance over time. Among socioeconomically disadvantaged groups, the association between flavonoid intake and measures of cognition is unclear. This study sought to identify associations between flavonoid intake and cognitive performance among Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study participants (n = 1947) across three study visits. Flavonoid intakes were assessed via two 24-h dietary recalls. Cognitive performance was assessed via the Trail Making Test (TMT)-A and TMT-B, which provide measures of attention and executive function, respectively. Mixed effects linear regression was used to model TMT scores over three study visits against visit 1 (v1) flavonoid intake, time (years from v1), and the interaction between v1 flavonoid intake and time, capturing both the cross-sectional association between flavonoid intake and time at v1 as well as the longitudinal association between v1 flavonoid intake and the change in TMT scores over time. Prior to adjustment, inverse cross-sectional associations at v1 were observed between (1) anthocyanidin intake and TMT-A scores for the overall sample and (2) total flavonoid, anthocyanidin, flavan-3-ol, flavone, and flavonol intake and TMT-B scores for the overall sample and among White adults. Only the association between anthocyanidin intake and TMT-B at v1 among White adults persisted after adjustment (for demographic characteristics such as age). One possible explanation for the few significant associations is universally low flavonoid intakes resulting from the consumption of an unhealthy dietary pattern.

A Comparison of 5 Measures of Accelerated Biological Aging and Their Association With Incident Cardiovascular Disease: The CARDIA Study

BACKGROUND

Accelerated biological aging is an increasingly popular way to track the acceleration of biology over time that may not be captured by calendar time. Biological aging has been linked to external and internal chronic stressors and has the potential to be used clinically to understand a person's personalized functioning and predict future disease. We compared the association of different measures of biological aging and incident cardiovascular disease (CVD) overall and by race.

METHODS AND RESULTS

We used multiple informants models to compare the strength of clinical marker-derived age acceleration, 5 measures of epigenetic age acceleration (intrinsic and extrinsic epigenetic age acceleration, GrimAge acceleration, and PhenoAge acceleration), and 1 established clinical predictor of future CVD, Framingham 10-year risk score, with incident CVD over an 11-year period (2007-2018). Participants were 913 self-identified Black or White (41% and 59%, respectively) female or male (51% and 49%, respectively) individuals enrolled in the US-based CARDIA (Coronary Artery Risk Development in Young Adults) cohort study. The analytic baseline for this study was the 20-year follow-up examination (2005-2006; median age 45 years). We also included race-specific analysis. We found that all measures were modestly correlated with one another. However, clinical marker-derived age acceleration and Framingham 10-year risk score were more strongly associated with incident CVD than all the epigenetic measures. Clinical marker-derived age acceleration and Framingham 10-year risk score were not significantly different than one another in their association with incident CVD.

CONCLUSIONS

The type of accelerated aging measure should be taken into consideration when comparing their association with clinical outcomes. A multisystem clinical composite shows associations with incident CVD equally to a well-known clinical predictor.

Why Not Offer Routine Screenings for Brain Health?

The merits of routine health screening for cancer and cardiovascular diseases are well established given the strong evidence that early detection can lead to effective interventions. Health systems, insurance providers and public health agencies have incorporated systematic approaches to ensuring that preventive screenings for hypertension, hyperlipidemia and cancers are encouraged, readily accessible and reimbursed. Workplace wellness programs intent on containing preventable healthcare costs have also sponsored age- and risk-adjusted health screenings, often including financial incentives to encourage same. Should we also screen for brain health? Is early detection of value for a condition with no proven treatment or cure? This editorial reviews the pros and cons of testing for cognitive decline, Alzheimer's and related dementias and suggests that with nearly every country in the world getting proportionally older, promoting brain health could emerge as a key intrinsic motivation for promoting healthier lifestyles. I conclude that a person-centered approach to deciding about testing is needed given uncertain evidence connecting health behaviors to cognitive decline.

Cognitive impairment and partnership status in the United States, 1998-2016, by sex, race/ethnicity, and education

Cognitively impaired adults without a partner are highly disadvantaged, as partners constitute an important source of caregiving and emotional support. With the application of innovative multistate models to the Health and Retirement Study, this paper is the first to estimate joint expectancies of cognitive and partnership status at age 50 by sex, race/ethnicity, and education in the United States. We find that women live a decade longer unpartnered than men. Women are also disadvantaged as they experience three more years as both cognitively impaired and unpartnered than men. Black women live over twice as long as cognitively impaired and unpartnered compared with White women. Lower-educated men and women live around three and five years longer, respectively, as cognitively impaired and unpartnered than more highly educated men and women. This study addresses a novel facet of partnership and cognitive status dynamics and examines their variations by key socio-demographic factors.

Is Early-Life Enrichment Associated With Better Cognitive Function Among Older Adults? Examining Home and School Environments

Objectives: We examine whether early-life enrichment, involving varied and stimulating activities to enhance cognitive function during childhood and adolescence, is associated with cognitive function in later life and whether the benefits persist over time. Methods: Growth curve models were used to examine up to five waves of data from the Health and Retirement Study-a nationally representative survey of adults 50 years and older (N = 10,070). We constructed separate measures of early-life enrichment to distinguish sources of influence (i.e., enriched home environment and enriched school environment). Global cognitive function was assessed with a modified version of the Telephone Interview for Cognitive Status. Results: Greater enrichment in each environment was incrementally associated with better cognitive function at baseline, but enrichment was not associated with change in cognitive function over time. Discussion: Receiving enrichment from multiple environments during sensitive periods of cognitive development may be advantageous for cognitive functioning in later life.

Life Course Religious Attendance and Cognitive Health at Midlife: Exploring Gendered Contingencies

A growing body of literature suggests that religious attendance might mitigate processes of cognitive decline associated with aging. However, few studies have made adequate linkages with the life course perspective. We draw from over 35 years of prospective panel data from the National Longitudinal Study of Youth (1979-2015) to assess the associations of cumulative exposures to religious attendance over the life course (childhood and midlife) for self-rated cognitive health and working memory (as assessed by the Serial 7s task). Our results suggest that midlife adults who attended religious services consistently between childhood and adulthood had higher self-rated cognitive health and better working memory. Women were also found to receive stronger benefits to self-rated cognitive health from consistent religious practice between childhood and adulthood. This pattern of findings allows for greater reflection into the neural enrichment and neural depletion arguments proposed to explain the religion/cognitive health link in previous research.

Amelioration of age-related cognitive decline and anxiety in mice by Centella asiatica extract varies by sex, dose and mode of administration

We have previously reported that a water extract (CAW) of the Ayurvedic plant Centella asiatica administered in drinking water can improve cognitive deficits in mouse models of aging and neurodegenerative diseases. Here we compared the effects of CAW administered in drinking water or the diet on cognition, measures of anxiety and depression-like behavior in healthy aged mice. Three- and eighteen-month-old male and female C57BL6 mice were administered rodent AIN-93M diet containing CAW (0, 0.2, 0.5 or 1% w/w) to provide 0, 200 mg/kg/d, 500 mg/kg/d or 1000 mg/kg/d for a total of 5 weeks. An additional group of eighteen-month-old mice were treated with CAW (10 mg/mL) in their drinking water for a total of five weeks to deliver the same exposure of CAW as the highest dietary dose (1000 mg/kg/d). CAW doses delivered were calculated based on food and water consumption measured in previous experiments. In the fourth and fifth weeks, mice underwent behavioral testing of cognition, anxiety and depression (n=12 of each sex per treatment group in each test). Aged mice of both sexes showed cognitive deficits relative to young mice while only female aged mice showed increased anxiety compared to the young female mice and no differences in depression were observed between the different ages. CAW (1000 mg/kg/d) in the drinking water improved deficits in aged mice in learning, executive function and recognition memory in both sexes and attenuated the increased measures of anxiety observed in the aged female mice. However, CAW in the diet only improved executive function in aged mice at the highest dose (1000 mg/kg/d) in both sexes and did so less robustly than when given in the water. There were no effects of CAW on depression-like behavior in aged animals regardless of whether it was administered in the diet or the water. These results suggest that CAW can ameliorate age-related changes in measures of anxiety and cognition and that the mode of administration is important for the effects of CAW on resilience to these age-related changes.

Estimating dementia risk in an African American population using the DCTclock

The prevalence of Alzheimer's disease (AD) and related dementias (ADRD) is increasing. African Americans are twice as likely to develop dementia than other ethnic populations. Traditional cognitive screening solutions lack the sensitivity to independently identify individuals at risk for cognitive decline. The DCTclock is a 3-min AI-enabled adaptation of the well-established clock drawing test. The DCTclock can estimate dementia risk for both general cognitive impairment and the presence of AD pathology. Here we performed a retrospective analysis to assess the performance of the DCTclock to estimate future conversion to ADRD in African American participants from the Rush Alzheimer's Disease Research Center Minority Aging Research Study (MARS) and African American Clinical Core (AACORE). We assessed baseline DCTclock scores in 646 participants (baseline median age = 78.0 ± 6.4, median years of education = 14.0 ± 3.2, 78% female) and found significantly lower baseline DCTclock scores in those who received a dementia diagnosis within 3 years. We also found that 16.4% of participants with a baseline DCTclock score less than 60 were significantly more likely to develop dementia in 5 years vs. those with the highest DCTclock scores (75-100). This research demonstrates the DCTclock's ability to estimate the 5-year risk of developing dementia in an African American population. Early detection of elevated dementia risk using the DCTclock could provide patients, caregivers, and clinicians opportunities to plan and intervene early to improve cognitive health trajectories. Early detection of dementia risk can also enhance participant selection in clinical trials while reducing screening costs.

Cognitive Assessment with Cognivue Clarity®: Psychometric Properties and Normative Ranges in a Diverse Population

Background

Detecting cognitive impairment in clinical practice is challenging as most instruments do not perform well in diverse samples of older adults. These same instruments are often used for eligibility into clinical trials making it difficult to recruit minoritized adults into Alzheimer's disease (AD) studies. Cognivue Clarity® is an FDA-cleared computerized 10-minute cognitive screening platform using adaptive psychophysics to detect cognitive impairment.

Objective

Test the ability of Cognivue Clarity to measure cognitive performance in a diverse community sample compared with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

Methods

This study enrolled 452 participants across 6 US study sites and completed both Cognivue Clarity device and RBANS. Psychometric properties and exploratory factor analysis of Cognivue Clarity were explored and comparisons against RBANS across different age, sex, education, and ethnoracial groups were conducted.

Results

Participants had a mean age of 47.9±16.1 years (range: 18-85), 63.6% were female, 45.9% had ≤12 years of education, 31.2% were African American and 9.2% were Hispanic. Cognivue Clarity had strong internal consistency, test-retest reliability and minimal practice effects. A 4-factor structure (Memory, Attention, Visuomotor, and Discrimination) had excellent goodness-of-fit. Normalizing age effects improved performance. Race and education effects were similar to those seen with RBANS. Cognivue Clarity had strong correlations with RBANS.

Conclusions

Our study supports the use of Cognivue Clarity as an easy-to-use, brief, and valid cognitive assessment that measures cognitive performance. In the correct clinical setting, Cognivue Clarity may identify individuals with likely cognitive impairment who could be candidates for AD research studies.

[Association between previous appendectomy and cognitive impairment in adults: a case-control study]

OBJECTIVE

To determine the relationship between appendectomy and cognitive impairment in adults aged 50-70 years.

MATERIAL AND METHODS

A case-control study was carried out with 270 patients between May and July 2023. Ninety cases (with cognitive impairment) and 180 controls (without impairment), diagnosed by the Montreal Cognitive Assessment (MoCA), were assessed.

RESULTS

31.11% of the total cases with cognitive impairment were submitted to an appendectomy, with an average of 25 years since surgery. Regarding other surgeries: 40% with impairment underwent cholecystectomy and 23.33% reported other operations. The analysis revealed significant differences in age, body mass index, hypertension, diabetes and smoking between the groups. However, there was no significant difference by gender. Logistic regression analysis highlighted that age and past appendectomy were strongly associated with cognitive impairment, with an Odds Ratio (OR) of 1.20 and 12.91, respectively. Associations were also found with cholecystectomy (OR 7.33), other surgeries (OR 13.39) and smoking (OR 6.91).

CONCLUSION

Appendectomy might be a significant risk factor for cognitive impairment in adults aged 50-70 years.

Effect of physio-cognitive dual-task training on cognition in pre-ageing and older adults with neurocognitive disorders: A meta-analysis and meta-regression of randomized controlled trial

Declines in cognitive performance, such as those seen in neurocognitive disorders (NCDs) are often associated with ageing. Both physical activity and cognitive training are common interventional strategies that can mitigate the decline in cognitive and physical performance. This review aims to (1) to evaluate the effects of Physio-Cognitive Dual-task Training (PCDT) intervention on cognition, physical performance, activities of daily living (ADL) and health-related quality of life (HRQoL) in pre-ageing and older adults with neurocognitive disorders, (2) explore the effects of covariates on intervention outcomes. A systematic search was conducted in eight databases. Cochrane's Risk of Bias Tool version 1 and GRADE criteria were used to assess risk of bias and certainty of evidence, respectively. Meta-analysis and meta-regression analyses were conducted using R software. Twenty-six randomized controlled trials involving 1,949 pre-ageing and older adults with NCDs were included in the meta-analysis. PCDT interventions had small-to-medium effect size on all cognition outcomes (g = 0.40-0.52) and instrumental ADL (g == 0.42), and a large effect size on HRQoL (g = 0.72). The quality of evidence was rated moderate to low for the outcome measures in pre-ageing and older adults with NCDs. These findings highlight the importance of PCDT interventions in preventing and slowing down cognitive impairment in pre-ageing and older adults. Registration: PROSPERO Number (CRD42020213962).

The importance of education for understanding variability of dementia onset in the United States

BACKGROUND

Greater levels of education are associated with lower risk of dementia, but less is known about how education is also associated with the compression of dementia incidence.

OBJECTIVE

We extend the literature on morbidity compression by evaluating whether increased levels of education are associated with greater dementia compression. We evaluate these patterns across race and gender groups.

METHODS

We use the Health and Retirement Study (2000-2016), a nationally representative longitudinal study of older adults in the United States. To evaluate the onset and compression of dementia across education groups, we examine the age-specific distribution of dementia events, identifying the modal age of onset and the standard deviation above the mode (a measure of compression).

RESULTS

While the modal age of onset is around 85 years among adults with a college degree, the modal age for adults with less than a high school education occurs before age 65 - at least a 20-year difference. The standard deviation of dementia onset is about three times greater for adults with less than a high school education compared to adults with a college degree. Patterns were consistent across race and gender groups.

CONCLUSION

This research highlights the variability of dementia experiences in the older population by documenting differences in longevity without dementia and compression of dementia onset among more educated adults and less educated adults.

CONTRIBUTION

We incorporate conceptual insights from the life span variability and compression literature to better understand education-dementia disparities in both the postponement and uncertainty of dementia onset in the US population.

Racial, Ethnic, Nativity, and Educational Disparities in Cognitive Impairment and Activity Limitations in the United States, 1998-2016

Despite extensive research on cognitive impairment and limitations in basic activities of daily living, no study has investigated the burden of their co-occurrence (co-impairment). Using the Health and Retirement Study data and incidence-based multistate models, we study the population burden of co-impairment using three key indicators: mean age at onset, lifetime risk, and health expectancy. We examine patterns by gender, race, ethnicity, nativity, education, and their interactions for U.S. residents aged 50-100. Furthermore, we analyze what fractions of racial, ethnic, and nativity disparities in co-impairment are attributable to inequalities in educational attainment. Results reveal that an estimated 56% of women and 41% of men aged 50 will experience co-impairment in their remaining life expectancy. Men experience an earlier onset of co-impairment than women (74 vs. 77 years), and women live longer in co-impairment than men (3.4 vs. 1.9 years). Individuals who are Black, Latinx, and lower educated, especially those experiencing intersecting disadvantages, have substantially higher lifetime risk of co-impairment, earlier co-impairment onset, and longer life in co-impairment than their counterparts. Up to 75% of racial, ethnic, and nativity disparity is attributable to inequality in educational attainment. This study provides novel insights into the burden of co-impairment and offers evidence of dramatic disparities in the older U.S. population.

The Impact of Online and Offline Social Support on the Mental Health of Carers of Persons with Cognitive Impairments

The carers of persons with cognitive impairments, including Alzheimer's have migrated to online platforms to seek help, yet studies on the use of online social support within the context of caregiving are underdeveloped. Guided by the social support theory, we examined the association of online and offline social support with depression and anxiety in the United States. Using a subsample from the 2017 and 2018 Health Information National Trends Survey (n = 264), we conducted ordered logistic regression to test mediation and moderation effects, which revealed that only offline, not online social support had a direct association with carers' mental health. In the moderation model, online social support interacted with life stressors, while offline social support interacted with caregiving burden. Findings are supported using a hybrid model that combines online and offline social support to improve carers' mental health.

Omega-3 index, cardiorespiratory fitness, and cognitive function in mid-age and older adults

Higher levels of omega-3 fatty acids in red blood cell membranes (omega-3 index or O3I) and cardiorespiratory fitness (CRF) are each associated with reduced cognitive impairment, but little research has examined the relationship between O3I and cognitive function while accounting for CRF. We analyzed cross-sectional data from 5,464 healthy men and women aged 55-85 years who had preventive medical examinations between 2009 and 2023. Primary exposures included O3I (<4.0%, 4.0-7.9%, or ≥ 8.0%) and age- and sex-based CRF quintile (1 = low, 2-3 = moderate, 4-5 = high). Cognitive impairment was defined as a Montreal Cognitive Assessment score of ≤ 25. We used Poisson regression to estimate relative risks (RR) of cognitive impairment, controlling for covariates. O3I < 4% was associated with increased cognitive impairment relative to ≥ 8.0% (RR, 1.21; 95% CI, 1.01-1.44) in a partially adjusted model. This association did not remain statistically significant in the fully adjusted model which included CRF. Low versus high CRF was associated with cognitive impairment (RR, 1.28; 95% CI, 1.07-1.53), independent of O3I and clinical biomarkers. The interaction between CRF and O3I was not significant (P = 0.8). In joint association analysis, risk of cognitive impairment was elevated with lower omega-3 index or CRF or both. Additional research is needed to fully understand the association between O3I and cognitive function at varying CRF levels.

Effect of Music Interventions on Cognitive Function in Older Adults With Mild Cognitive Impairment: A Systematic Review

The purpose of the current systematic review was to examine the effects of music interventions on cognitive function in older adults with mild cognitive impairment (MCI). A systematic search of CINAHL, PubMed, PsycINFO, and Web of Science databases was performed. Studies examining the effects of music interventions on cognitive function in older adults with MCI were included. Narrative synthesis for cognitive outcomes postintervention was performed. A total of 11 articles met inclusion criteria. Music interventions significantly improved global cognitive function, verbal fluency, executive function, and spatial function in older adults with MCI. Included studies were heterogeneous in terms of the type of intervention, cognitive assessment tool, and intervention duration. Six studies were at risk of bias due to missing data and confounding factors. Our findings suggest that music interventions can be an effective strategy to improve cognitive function for older adults with MCI. However, findings should be interpreted with caution. More rigorous studies with various types of music interventions investigating cognitive domain-specific effects are needed. [Research in Gerontological Nursing, 16(5), 259-268.].

Design of the think PHRESH longitudinal cohort study: Neighborhood disadvantage, cognitive aging, and alzheimer's disease risk in disinvested, black neighborhoods

BACKGROUND

Black Americans have disproportionately higher rates and earlier onset of Alzheimer's disease and related dementias (ADRD) relative to White Americans. We currently lack a comprehensive understanding of how the lived experience and broader societal factors, including cumulative exposure to structural racism and the mechanisms underlying the risks, may contribute to elevated ADRD risk in Black Americans.

METHODS

The Think PHRESH study builds on existing, community-based research infrastructure, from the ongoing Pittsburgh Hill/Homewood Research on Neighborhood Change and Health (PHRESH) studies, to examine the contributions of dynamic neighborhood socioeconomic conditions across the lifecourse to cognitive outcomes in mid- and late-life adults living in two historically disinvested, predominantly Black communities (anticipated n = 1133). This longitudinal, mixed-methods study rests on the premise that neighborhood racial segregation and subsequent disinvestment contributes to poor cognitive outcomes via factors including (a) low access to educational opportunities and (b) high exposure to race- and socioeconomically-relevant stressors, such as discrimination, trauma, and adverse childhood events. In turn, these cumulative exposures foster psychological vigilance in residents, leading to cardiometabolic dysregulation and sleep disruption, which may mediate associations between neighborhood disadvantage and ADRD risk. This premise recognizes the importance of potential protective factors that may promote cognitive health, including neighborhood social cohesion, safety, and satisfaction. The proposed study will leverage our existing longitudinal data on risk/protective factors and biobehavioral mediators and will include: (1) up to three waves of cognitive assessments in participants ages 50 years + and one assessment in participants ages 35-49 years; clinical adjudication of ADRD will be completed in participants who are 50+, (2) extensive surveys of risk and protective factors, (3) two assessments of blood pressure and objectively measured sleep, (4) a comprehensive assessment of life and residential history; and (5) two rounds of in-depth qualitative interviews to reveal lifecourse opportunities and barriers experienced by Black Americans in achieving optimal cognitive health in late life.

DISCUSSION

Understanding how structural racism has influenced the lived experience of Black Americans, including dynamic changes in neighborhood conditions over time, is critical to inform multi-level intervention and policy efforts to reduce pervasive racial and socioeconomic disparities in ADRD.

Feasibility of a Modified Otago Exercise Program for Older Adults With Cognitive Vulnerability

Cognitive vulnerability, that is, clinically significant symptoms of dementia, depression, or delirium, puts older adults at high risk for physical inactivity and falls. Programs addressing activity and falls are needed. The purpose was to determine feasibility of an in-home, modified, Otago Exercise Program (OEP) for those with cognitive vulnerability, based on acceptability (retention and adherence), safety (pain intensity and falls), and potential positive effects (change in short physical performance battery (SPPB)). This secondary analysis of a randomized controlled trial included 80 participants who received the OEP; 64 completed it, 48% had depression, 22% had dementia, and 30% had a combination dementia/depression/delirium. Adherence to home exercise was low to moderate; pain was stable over 16 weeks; 31% of participants reported falls unrelated to OEP. SPPB increased from 6.95 to 7.74 (p < .01); age by time and diagnosis by time interactions were not significant. The modified OEP shows promising feasibility for older adults with cognitive vulnerability.

Genetic variants in the SHISA6 gene are associated with delayed cognitive impairment in two family datasets

INTRODUCTION

Studies of cognitive impairment (CI) in Amish communities have identified sibships containing CI and cognitively unimpaired (CU) individuals. We hypothesize that CU individuals may carry protective alleles delaying age at onset (AAO) of CI.

METHODS

A total of 1522 individuals screened for CI were genotyped. The outcome studied was AAO for CI individuals or age at last normal exam for CU individuals. Cox mixed-effects models examined association between age and single nucleotide variants (SNVs).

RESULTS

Three SNVs were significantly associated (P < 5 × 10-8 ) with AAO on chromosomes 6 (rs14538074; hazard ratio [HR] = 3.35), 9 (rs534551495; HR = 2.82), and 17 (rs146729640; HR = 6.38). The chromosome 17 association was replicated in the independent National Institute on Aging Genetics Initiative for Late-Onset Alzheimer's Disease dataset.

DISCUSSION

The replicated genome-wide significant association with AAO on chromosome 17 is located in the SHISA6 gene, which is involved in post-synaptic transmission in the hippocampus and is a biologically plausible candidate gene for Alzheimer's disease.

Relationships of Low Cognitive Performance and Sleep Disorder With Functional Disabilities Among Older Adults

Objectives

This study examined the relationships of low cognitive performance and sleep disorder with functional disabilities among older adults. Methods: NHANES 2011–2014 data on 3179 individuals [Mage=69.71] were analyzed. Functional domains included: activities of daily living (ADL), instrumental ADL (IADL) and leisure and social activities (LSA). Animal Fluency Test and the Digit Symbol Substitution Test assessed cognitive performance. Participants self-reported having physician-diagnosed sleep disorder. Results: Participants with both low cognitive performance and sleep disorder had 4- to 10-times greater odds for ADL, IADL, and LSA difficulties compared to the participants with no low cognitive performance/sleep disorder. Participants with only low cognitive performance and those with only sleep disorder were two to three times more likely to experience these difficulties. Discussion: Low cognitive performance and sleep disorder together or independently were associated with functional disabilities. Participants with both low cognitive performance and sleep disorder had higher odds of functional disabilities.

Differential Impact of Stroke on Cognitive Impairment in Mexican Americans and Non-Hispanic White Americans

BACKGROUND

The association between stroke and dementia is well established. Less is known about this association in underrepresented ethnic groups. In a large ethnically diverse cohort, we examined whether history of stroke was associated with cognitive impairment, and whether this relationship differed by ethnicity (Mexican American [MA] versus non-Hispanic White).

METHODS

This was a population-based cohort study conducted in Nueces County, TX, a biethnic community with a large and primarily nonimmigrant MA population. Residents aged ≥65 were recruited door-to-door or by telephone between May 2018 and December 2021. The primary exposure was history of stroke, obtained by self-report. Demographic, medical, and educational histories were also obtained. The primary outcome was the Montreal Cognitive Assessment (MoCA), a scale that evaluates multiple domains of cognitive performance. Scores were divided into 3 ordinal categories, roughly corresponding to normal cognition (MoCA 26-30), mild cognitive impairment (MoCA 20-25), or probable dementia (MoCA 0-19).

RESULTS

One thousand eight hundred one participants completed MoCA screening (55% female; 50% MA, 44% Non-Hispanic White, 6% other), of whom 12.4% reported history of stroke. Stroke prevalence was similar across ethnicities (X2 2.1; P=0.34). In a multivariable cumulative logit regression model for the ordinal cognition outcome, a stroke by ethnicity interaction was observed (P=0.01). Models stratified by ethnicity revealed that stroke was associated with cognitive impairment across ethnicities, but had greater impact on cognition in non-Hispanic Whites (cumulative odds ratio=3.81 [95% CI, 2.37-6.12]) than in MAs (cumulative odds ratio=1.58 [95% CI, 1.04-2.41]). Increased age and lower educational attainment were also associated with cognitive impairment, regardless of ethnicity.

CONCLUSIONS

History of stroke was associated with increased odds of cognitive impairment after controlling for other factors in both MA and Non-Hispanic White participants. The magnitude of the impact of stroke on cognition was less in MA than in Non-Hispanic White participants.

Can cochlear implantation prevent cognitive decline in the long-term follow-up?

Cognitive function and hearing are known to both decline in older adults. As hearing loss is proposed to be one modifiable risk factor for dementia, the impact of auditory rehabilitation on cognitive decline has been gaining increasing attention. Despite a large number of studies, long-term data are still rare. In a large prospective longitudinal monocentric study, 50 adults (aged ≥ 50 years) with severe postlingual bilateral hearing loss received a cochlear implant (CI). They underwent comprehensive neurocognitive testing prior to implantation (T1), at 12 months (T2) and up to 65 months (T3) after implantation. Various cognitive subdomains such as attention, inhibition, working memory, verbal fluency, mental flexibility and (delayed) recall were assessed by the computer-based non-auditory test battery ALAcog^©. The observed trajectories of two exemplary cognitive subdomains (delayed recall and working memory) were then fitted over time using multilevel growth models to adjust for sociodemographic covariates and compared with 5-year longitudinal data from a sample of older adults from the representative Survey of Health, Aging and Retirement in Europe (SHARE) study. Postoperatively, auditory functions improved from 6.98% (SD 12.83) to 57.29% (SD 20.18) in monosyllabic speech understanding. Cognitive functions significantly increased from T1 to T3 in attention (p = 0.001), delayed recall (p = 0.001), working memory (OSPAN; p = 0.001), verbal fluency (p = 0.004), and inhibition (p = 0.002). A closer look at follow-up revealed that cognitive improvement could be detected between T1 and T2 and thereafter remained stable in all subtests (p ≥ 0.06). Additional longitudinal analysis confirmed these findings in a rigorous multilevel approach in two exemplary cognitive subdomains. In contrast to the SHARE data, there was no evidence for age-differential associations over time in CI recipients. This suggests that older adults benefit equally from cochlear implantation. CI users with worse preoperative cognitive skills experienced the most benefit (p < 0.0001). Auditory rehabilitation by cochlear implantation has a stimulating effect on cognitive functions beyond an improvement in speech understanding and an increased well-being. Large multicenter studies using standardized protocols have to be undertaken in the future to find out whether hearing restoration might help to prevent cognitive decline.

Understanding heterogeneity of responses to, and optimizing clinical efficacy of, exercise training in older adults: NIH NIA Workshop summary

Exercise is a cornerstone of preventive medicine and a promising strategy to intervene on the biology of aging. Variation in the response to exercise is a widely accepted concept that dates back to the 1980s with classic genetic studies identifying sequence variations as modifiers of the VO₂max response to training. Since that time, the literature of exercise response variance has been populated with retrospective analyses of existing datasets that are limited by a lack of statistical power from technical error of the measurements and small sample sizes, as well as diffuse outcomes, very few of which have included older adults. Prospective studies that are appropriately designed to interrogate exercise response variation in key outcomes identified a priori and inclusive of individuals over the age of 70 are long overdue. Understanding the underlying intrinsic (e.g., genetics and epigenetics) and extrinsic (e.g., medication use, diet, chronic disease) factors that determine robust versus poor responses to various exercise factors will be used to improve exercise prescription to target the pillars of aging and optimize the clinical efficacy of exercise training in older adults. This review summarizes the proceedings of the NIA-sponsored workshop entitled, "Understanding Heterogeneity of Responses to, and Optimizing Clinical Efficacy of, Exercise Training in Older Adults" and highlights the importance and current state of exercise response variation research, particularly in older adults, prevailing challenges, and future directions.

Associations Between Cognitive Functioning and Mortality in a Population-Based Sample of Older United States Adults: Differences by Sex and Education

Objective: To determine whether cognition is associated with mortality among older US adults. Methods: We studied 5,989 National Health and Nutrition Examination Survey participants age 60+ in years 1999-2014 with mortality follow-up through 2015. Cognitive function was measured in one standard deviation decrements using the Digit Symbol Substitution Test (DSST), Animal Fluency (AnFl), and two Consortium to Establish a Registry for Alzheimer's Disease (CERAD) tests. Results: Each decrement in cognitive function was associated with increased risk of mortality overall (DSST HR: 1.36, 95% CI: 1.25, 1.48), among women only (AnFl: 1.51, 95% CI: 1.02, 2.24), and among those with less than a high school education only (AnFl HR: 1.46, 95% CI: 1.09, 1.97; CERAD-WL HR: 1.34, 95% CI: 1.07, 1.67; and CERAD-DR HR: 1.38, 95% CI: 1.05, 1.82). Discussion: Among US adults, lower cognitive functioning was associated with mortality; associations were stronger among women and those with less education.

Regional variation in U.S dementia trends from 2000-2012

Although recent studies report a decline in dementia prevalence among U.S. older adults, national trends may mask subnational variation, particularly given large health and social inequalities linked to geography. To address this gap, we determined if there was subnational variation in reported national dementia trends and if region-specific trends were explained by sociodemographic and health characteristics. Data come from the 2000 (n = 10,447) and 2012 (10,426) waves of the Health and Retirement Study. We used validated methods for dementia classification using proxy and self-respondents. Logistic regression models, adjusted for within-person clustering over time, estimated trends in dementia prevalence by region and census division. We found subnational variation in dementia prevalence in both 2000 and 2012, as well as in change in dementia prevalence during this period. In 2000, dementia prevalence was lowest in the West (8.6%), higher in the Midwest (10.0%) and Northeast (11.1%), and highest in the South (14.6%). Dementia prevalence declined over time across all regions of the U.S. from 2000 to 2012 but remained highest in the South (10.7%) compared to the other regions (7.0-7.8%). Despite downward trends in dementia across the U.S., the prevalence of dementia in the South in 2012 approximated levels found in other regions in 2000. There was relatively less change over time in the West compared to other regions, but dementia prevalence was already quite low in the West in 2000. Within region, trends in dementia prevalence between 2000 and 2012 also varied slightly across census divisions. Subnational variation in changes in dementia prevalence were largely explained by education and health status. Variation in baseline prevalence, as well as differential rates of change, highlight the importance of examining subnational variation in dementia trends.

Strategies for Maintaining Brain Health: The Role of Stroke Risk Factors Unique to Elderly Women

Stroke risk and prevalence increase with advanced age and women tend to be older than men at the time of their first stroke. Advanced age in women confers unique stroke risks that are beyond reproductive factors. Previous reviews and guidelines have largely focused on risk factors specific to women, with a predominant focus on reproductive factors and, therefore, younger to middle-aged women. This review aims to specifically describe stroke risk factors in elderly women, the population of women where the majority of strokes occur, with a focus on atrial fibrillation, hormone therapy, psychosocial risk factors, and cognitive impairment. Our review suggests that prevention and management of stroke risks that are unique or more prevalent in elderly women needs a coordinated system of care from general physicians, general neurologists, vascular and cognitive neurologists, psychologists, cardiologists, patients, and their caretakers. Early identification and management of the elderly woman-specific and traditional stroke risk factors is key for decreasing stroke burden in elderly women. Increased education among elderly women regarding stroke risk factors and their identification should be considered, and an update to the guidelines for prevention of stroke in women is strongly encouraged.

Assessing Public Opinions of Sexual Advance Directives Among Older Adults With Dementia

This study used a mixed-method research design to examine public attitudes toward sexual advance directives (SADs), a theoretical legal document intended to protect the sexual rights of individuals across the lifespan. Respondents (N = 537) largely indicated that SADs should exist (65.4%) to preserve autonomy and protect resident rights, but they would not sign one right now (60.4%) because they were too young. Linear regression analyses revealed statistical associations between education level, relationship length, and sexual instrumentality for the existence of SADs, while gender, age, perceived importance of sexuality, and sexual self-disclosure were associated with whether a respondent would sign the document now. Overall analyses indicate that valuing sexual expression as a right, autonomy, sexuality in older age, and sexual communication led to a greater amount of general support for SADs. Respondents were sensitive to the concerns of SADs in the context of fluid consent between partners and their safety.

Trajectories of physical functioning among US adults with cognitive impairment

BACKGROUND

physical functioning impairment is common among persons with cognitive impairment, but little is known about physical functioning trajectories across the US population or how trajectories may differ among persons with dementia and mild cognitive impairment (MCI).

OBJECTIVE

to examine trajectories of physical functioning among persons with MCI and dementia in the USA.

DESIGN

we used data from the National Health and Aging Trends study (NHATS) 2011-18. Physical functioning was assessed using the NHATS Expanded Short Physical Performance Battery.

PARTICIPANTS

the 661 individuals with MCI and 980 individuals with dementia were included in this study.

METHODS

we applied group-based trajectory models to identify latent groups and estimate their trajectories. Multinomial logistic regressions were applied to examine relationships between sociodemographic and health characteristics and trajectory group memberships.

RESULTS

both MCI- and dementia-specific trajectories differed at baseline levels and declined at varying rates across groups. Approximately, 78.43% of persons with MCI were in trajectories with a moderate rate of decline, with only 9.75% in a trajectory with good physical function and 11.82% with poor physical function without as much change over time. Among persons with dementia, approximately 81.4% experienced moderate or fast declines, and 18.52% with virtually no functional ability remained at this same low level. Worse physical functioning trajectories were found among persons who were females, Blacks, with at least four comorbidities, and among persons who had a low socioeconomic status.

CONCLUSIONS

persons with both dementia and MCI experienced steady declines in physical functioning. Socioeconomically disadvantaged groups have worse physical functioning trajectories.

Gut bacterial isoamylamine promotes age-related cognitive dysfunction by promoting microglial cell death

The intestinal microbiome releases a plethora of small molecules. Here, we show that the Ruminococcaceae metabolite isoamylamine (IAA) is enriched in aged mice and elderly people, whereas Ruminococcaceae phages, belonging to the Myoviridae family, are reduced. Young mice orally administered IAA show cognitive decline, whereas Myoviridae phage administration reduces IAA levels. Mechanistically, IAA promotes apoptosis of microglial cells by recruiting the transcriptional regulator p53 to the S100A8 promoter region. Specifically, IAA recognizes and binds the S100A8 promoter region to facilitate the unwinding of its self-complementary hairpin structure, thereby subsequently enabling p53 to access the S100A8 promoter and enhance S100A8 expression. Thus, our findings provide evidence that small molecules released from the gut microbiome can directly bind genomic DNA and act as transcriptional coregulators by recruiting transcription factors. These findings further unveil a molecular mechanism that connects gut metabolism to gene expression in the brain with implications for disease development.

Spatial transcriptomic analysis reveals inflammatory foci defined by senescent cells in the white matter, hippocampi and cortical grey matter in the aged mouse brain

There is strong evidence that aging is associated with an increased presence of senescent cells in the brain. The finding that treatment with senolytic drugs improves cognitive performance of aged laboratory mice suggests that increased cellular senescence is causally linked to age-related cognitive decline. The relationship between senescent cells and their relative locations within the brain is critical to understanding the pathology of age-related cognitive decline and dementia. To assess spatial distribution of cellular senescence in the aged mouse brain, spatially resolved whole transcriptome mRNA expression was analyzed in sections of brains derived from young (3 months old) and aged (28 months old) C57BL/6 mice while capturing histological information in the same tissue section. Using this spatial transcriptomics (ST)-based method, microdomains containing senescent cells were identified on the basis of their senescence-related gene expression profiles (i.e., expression of the senescence marker cyclin-dependent kinase inhibitor p16INK4A encoded by the Cdkn2a gene) and were mapped to different anatomical brain regions. We confirmed that brain aging is associated with increased cellular senescence in the white matter, the hippocampi and the cortical grey matter. Transcriptional analysis of the senescent cell-containing ST spots shows that presence of senescent cells is associated with a gene expression signature suggestive of neuroinflammation. GO enrichment analysis of differentially expressed genes in the outer region of senescent cell-containing ST spots ("neighboring ST spots") also identified functions related to microglia activation and neuroinflammation. In conclusion, senescent cells accumulate with age in the white matter, the hippocampi and cortical grey matter and likely contribute to the genesis of inflammatory foci in a paracrine manner.

Race/Ethnic Differences, Skin Tone, and Memory Among Older Latinos in the United States

OBJECTIVES

U.S. Latino populations are diverse. Research on racial identity, skin tone, and Latino health is imperative for understanding and combating racism and colorism. We examined differences in memory performance: among non-Latinos and Latinos who identified as Black, other, and White in the United States and then among Puerto Ricans in Boston whose skin tones ranged from dark, medium, light to "white."

METHODS

We used 2010 Health and Retirement Study and 2004 Boston Puerto Rican Health Survey data, respectively, to examine racial and color differences in memory performance among 50 and older adults in the United States and Puerto Rican older adults in Boston. We applied ordinary least squares regression to immediate and delayed word recall test scores and adjusted for education, health conditions, and health behaviors.

RESULTS

In adjusted models, White non-Latinos had better memory performance than White Latinos. Black Latinos, other Latinos, and Black non-Latinos had lower delayed word recall scores than White Latinos. Black Latinos and Black non-Latinos had similar scores. Intra-Latino racial disparities endured despite the inclusion of education and other covariates. Among Puerto Ricans in Boston, medium-toned individuals had higher scores than "white"-toned individuals.

DISCUSSION

Findings support the importance of examining self-identified race and skin tone in Latino aging research. Further investigation is needed to understand the stubborn intra-Latino racial disparities in memory performance and surprising adverse cognitive performance among "white"-toned relative to darker-toned Puerto Ricans in Boston.

Sex-Specific Associations of Dietary Iron Intake with Brain Iron Deposition on Imaging and Incident Dementia: A Prospective Cohort Study

OBJECTIVES

The study aimed to evaluate the association of dietary iron intake with incident dementia and brain iron deposition.

DESIGN/SETTING/PARTICIPANTS

We included dementia-free participants from the UK Biobank who completed at least one 24-hour dietary recall at study baseline (2009-2012) and were followed up to 2021. Incident dementia was determined through linkage to medical records and death registries. Brain MRI was conducted in a subgroup of participants since 2014, with T2* measurements being used as indicators of brain iron deposition.

MEASUREMENTS

Cox proportional hazard models were used to assess the associations of high (top quintile) and low (bottom quintile) versus medium (quintile 2 to 4) level of dietary iron intake with incident dementia, respectively. Linear regression was applied to assess the relations between dietary iron intake and brain T2* measurements.

RESULTS

During follow-up (mean = 9.5 years), a total of 1,454 participants (650 women and 804 men) developed dementia among 191,694 participants (55.0% female; mean age, 56.2 years). When adjusted for sociodemographic, lifestyle, and other dietary factors, participants with low dietary iron intake (< 10.05 mg/day) had a significantly higher dementia risk (hazard ratio [HR], 1.50, 95% confidence interval [CI], 1.19-1.89), while the relation for high intake (> 16.92 mg/day) was non-significant (HR, 1.16, 95% CI, 0.92-1.46). A significant gender difference (P-interaction < 0.001) was observed, with a U-shaped association in male participants (HR for low vs. medium, 1.56, 95% CI, 1.14-2.13; HR for high vs. medium, 1.39, 95% CI, 1.03 - 1.88; P-nonlinearity < 0.001) and no significant association in females, regardless of their menopause status. In general, dietary iron intake was not related to T2* measurements of iron deposition in most brain regions.

CONCLUSION

Our findings suggested a U-shape relationship between dietary iron intake and risk of dementia among males, but not females.

Knowledge About COVID-19 Symptoms, Transmission, and Prevention: The Relationship With Cognitive Status in Older Adults

Objective: Advanced age poses an increased risk for cognitive impairment, and therefore, poor knowledge regarding the risks associated with COVID-19 may confer vulnerability. We administered a COVID-19 Knowledge Questionnaire to older persons to evaluate the association between knowledge regarding public health recommendations, and cognitive status as measured by the Montreal Cognitive Assessment (MoCA). Method: Ninety-nine participants completed a 22-item questionnaire about COVID-19 symptoms, risks, and protective strategies, and they also completed the MoCA. Associations between knowledge and cognitive status were examined via Spearman correlations. Results: The mean (SD) age of participants was 72.6 (7.6) years, and MoCA scores averaged 23.4 (4.5) points. Higher MoCA total scores were significantly (p < .001) correlated with a greater number of correct questionnaire responses. Higher Orientation and Memory Index scores were moderately associated with an increased number of correct responses (p < .001), with the Executive Index exhibiting a significant albeit weaker association. MoCA Index scores assessing attention, language, and visuospatial functioning were not significantly associated with COVID-19 knowledge. Conclusions: Given the rapid transmission rate of the SARS CoV-2 infections, COVID knowledge lapses will likely have deleterious repercussions. Public health messages should ensure effective acquisition and retention of COVID specific information, especially in cognitively compromised older adults.

The Role of Vitamin E in Slowing Down Mild Cognitive Impairment: A Narrative Review

With the aging population, dementia emerges as a public health concern. In 2012, the Health and Retirement Study found that 8.8% of adults over 65 years suffered from dementia. The etiopathogenesis and treatment of dementia are not well understood. Antioxidant properties of Vitamin E and its major elements tocopherols and tocotrienols have been reported to be effective in slowing down the progression of dementia from its initial stage of Mild cognitive impairment (MCI). Therefore, the current review aims to explore the role of vitamin E on MCI. A literature search using the key words "Vitamin E, tocopherols, tocotrienols, and mild cognitive impairment" was conducted in MEDLINE (PubMed), CINAHL, and Google Scholar. The inclusion criteria were: (1) articles published in the past ten years; (2) published in English language; (3) published in peer-reviewed journals; and (4) descriptive and epidemiological or evaluation studies. Articles published prior to 2010, focused on other forms of dementia than MCI, grey literature and non-peer-reviewed articles were excluded. A total of 22 studies were included in the narrative synthesis. The results were equivocal. Eleven studies showed some level of the neuroprotective effect of Vitamin E, tocopherols and tocotrienols on the progression of MCI. The mixed results of this review suggest further exploration of the possible protective effects of Vitamin E on the development of dementia. Future studies can be conducted to decipher antioxidant properties of vitamin E and its association with slowing down the cognitive decline.

Family-Centered Primary Care for Older Adults with Cognitive Impairment

Cognitive impairment (e.g. dementia) presents challenges for individuals, their families, and healthcare professionals alike. The primary care setting presents a unique opportunity to care for older adults living with cognitive impairment, who present with complex care needs that may benefit from a family-centered approach. This indepth systematic review was completed to address three aims: (a) identify the ways in which families of older-adult patients with cognitive impairment are engaged in primary care settings, (b) examine the outcomes of family engagement practices, and (c) organize and discuss the findings using CJ Peek's Three World View. Researchers searched PubMed, Embase, and PsycINFO databases through July 2019. The results included 22 articles out of 6743 identified in the initial search. Researchers provided a description of the emerging themes for each of the three aims. It revealed that family-centered care and family engagement yields promising results including improved health outcomes, quality care, patient experience, and caregiver satisfaction. Furthermore, it promotes and advances the core values of medical family therapy: agency and communion. This review also exposed the inconsistent application of family-centered practices and the need for improved interprofessional education of primary care providers to prepare multidisciplinary teams to deliver family-centered care. Utilizing the vision of Patient- and Family-Centered Care and the lens of the Three World View, this systematic review provides Medical Family Therapists, healthcare administrators, policy makers, educators, and clinicians with information related to family engagement and how it can be implemented and enhanced in the care of patients with cognitive impairment.

Identification of hub genes associated with cognition in the hippocampus of Alzheimer's Disease

Alzheimer’s Disease (AD) is a neurodegenerative disease featured by cognitive impairment. This bioinformatic analysis was used to identify hub genes related to cognitive dysfunction in AD. The gene expression profile GSE48350 in the hippocampus of AD patients aged >70 years was obtained from the Gene Expression Omnibus (GEO) database. A total of 96 differentially expressed genes (DEGs) were identified, and subjected to Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses; a protein–protein interaction (PPI) network was constructed. The DEGs were enriched in synapse-related changes. A protein cluster was teased out of PPI. Furthermore, the cognition ranked the first among all the terms of biological process (BP). Next, 4 of 10 hub genes enriched in cognition were identified. The function of these genes was validated using APP/PS1 mice. Cognitive performance was validated by Morris Water Maze (MWM), and gene expression by RT-qPCR, Cholecystokinin (CCK), Tachykinin precursor 1 (TAC1), Calbindin 1 (CALB1) were downregulated in the hippocampus. These genes can provide new directions in the research of the molecular mechanism of AD.