The Association between Social Engagement, Loneliness, and Risk of Dementia: A Systematic Review and Meta-Analysis

PROTOCOL: Understanding Intergenerational Programmes to Improve the Psychosocial Health and Well-Being of Older Adults in Residential Aged Care: A Rapid Realist Review Protocol

This is the protocol for a Campbell systematic review. The objectives are as follows. The aim of this study is to briefly outline the objectives of the proposed review. While Campbell systematic reviews might be motivated by many reasons, their overarching aim should be to gather, summarise and integrate empirical research so as to help people understand the evidence.

Prolonged loneliness and risk of incident cognitive decline and dementia: A two-cohort study

BACKGROUND

Loneliness is prevalent currently and could result in increased dementia risks, whereas the associations of prolonged loneliness and its changes with cognitive decline and dementia remain less investigated.

METHODS

Data were from the English Longitudinal Study of Ageing (ELSA) and Health and Retirement Study (HRS). Loneliness was assessed using the Revised UCLA Loneliness Scale. Health risk factors for dementia included unhealthy lifestyles, depressive symptoms, chronic diseases, and functional limitations. Cognitive function was assessed using validated tests in both cohorts, with cognitive decline defined as cognitive z-scores < -1.5. Dementia was identified through self- or proxy-reported physician diagnoses. The Cox proportional hazard regression and Aalen's additive hazard regression were performed to calculate the relative and absolute risk for cognitive decline and dementia, respectively. Covariates including socio-demographic characteristics, social networks, and polygenic scores were adjusted.

RESULTS

Of 6721 ELSA and 10,195 HRS participants aged ≥50y, 2129 (13.7 %) and 612 (3.6 %) developed incident cognitive decline and dementia in about 10 years, respectively. Participants with severe (versus no) cumulative loneliness had 42 % and 98 % higher cognitive decline and dementia risks after pooling, corresponding to 791.6 (477.4-1105.8) and 372.8 (223.6-522.0) excess incidence densities (/105 person-years). Additionally, those who recovered from frequent loneliness (versus persistent frequent) were 9 %-31 % less likely to develop unhealthy lifestyles, depressive symptoms, chronic diseases, and functional limitations, and were at 33 % lower risks of dementia, corresponding to -248.6 (-446.0 ~ -51.2) excess incidence density.

CONCLUSIONS

Prolonged loneliness could increase the risks of incident cognitive decline and ADRD, while alleviating loneliness may help.

Association between social networking and dementia: A systematic review of observational studies

Poor social networking (SN) is associated with the development of cognitive impairment and dementia. Our objective was to perform a systematic review of the evidence on the associations between SN and the incidence of dementia, disease pathology, level of cognition, and brain structure. Bibliographic databases (PubMed, Embase, Cochrane Library, CINAHL) and additional sources (Open Gray, Google Scholar, manual searches) were screened through November 30, 2024. Observational studies assessing the SN-dementia link were selected, with data extraction and bias evaluation performed independently by two authors via the PRISMA checklist and Newcastle-Ottawa Scale. We included 17 observational studies (355 initially screened), involving 20,678 participants aged 40-90 years, published between 2000 and 2024. Studies have utilized various SN assessment tools and cognitive measures, including the MMSE and MoCA. Poor SN was consistently associated with increased risks of dementia, cognitive decline, and severe disease pathology, particularly Alzheimer's disease (AD). Larger and more integrated SNs were linked to better cognitive resilience and lower conversion rates from mild cognitive impairment (MCI) to dementia. One study on frontotemporal dementia (FTD) indicated that the SN might mitigate cortical atrophy. SN size and density are also correlated with favorable structural brain changes, such as greater gray matter volume. This review highlights SN as a modifiable factor in dementia risk. However, its role in non-AD dementia, particularly FTD, requires further investigation. Future research should include more culturally diverse and methodologically robust studies. Randomized controlled trials will be important to determine whether intervention to expand social networks decreases incidence of progression of dementia.

Relationship between immediate memory, depressive symptomatology and loneliness in older adults: a longitudinal study

OBJECTIVES

We aimed to study the longitudinal relationship between immediate memory, depressive symptomatology and loneliness controlling for age and number of chronic diseases over time.

METHOD

The study sample consisted of 64,887 participants from three consecutive waves of the Survey of Health, Ageing and Retirement in Europe project, aged 50 or older at the first time (M = 66.68, SD = 10.034). We used cross-lagged panel model.

RESULTS

Within each temporal moment, associations between immediate memory and depressive symptomatology, and associations between immediate memory and loneliness were negative. Associations between depressive symptomatology and loneliness were positive. These three variables feedback on each other over time through small and medium effects. Immediate memory is more affected by depressive symptomatology than by loneliness. However, loneliness may exert a greater negative effect, in relative terms, on immediate memory when it coexists with depressive symptomatology. Depressive symptomatology is more affected by loneliness than by immediate memory deficits. However, deficits in immediate memory may affect depressive symptomatology more in relative terms because such deficits are exacerbated by elevated scores of depressive symptomatology.

CONCLUSION

Despite the effect sizes being small to medium, depressive symptomatology and loneliness are risk factors for cognitive functioning. In addition, cognitive impairment aggravates depressive symptoms and loneliness feelings.

The Impact of Kinlessness on Older Adults with Advanced Heart Failure

Markers of social health, including kinlessness, social isolation and loneliness, have important implications for quality of life and health for older adults. As the population ages, there is a growing cohort of kinless older adults without living partners or children, particularly among disadvantaged groups. Kinlessness has been associated with worse mental and physical health, significant unmet care needs, increased risk of dementia, higher rates of long-term placement, and higher mortality rates than those for patients with kin. Although other markers of social health have been studied in patients with heart failure, little is known about kinlessness in this population of patients. This review outlines the data on kinlessness and its impact on patients' outcomes, and it proposes novel interventions to mitigate its effects.

Selected social and lifestyle correlates of brain health markers: the Cross-Cohort Collaboration Consortium

INTRODUCTION

To investigate the associations of education level, marital status, and physical activity with dementia risk and brain MRI markers.

METHODS

Data from six community-based samples from the Cross-Cohort Collaboration Consortium were analyzed. Self-reported education level, marital status, and physical activity at age 60 to 75 years were harmonized. Subsamples of participants with brain MRI markers at time of exposure were selected. Associations with dementia risk and cross-sectional MRI markers were meta-analyzed.

RESULTS

Higher education level was associated with lower dementia risk (hazard ratio [HR] = 0.65, 95% confidence interval [CI] = 0.59; 0.72 vs low level) but not significantly with brain MRI markers. Compared with being unmarried, being married was only associated with higher total brain and hippocampal volumes. Being physically active was associated with lower dementia risk (HR = 0.73, 95% CI = 0.52; 1.04), as well as larger total brain volume and smaller white matter hyperintensity volume.

DISCUSSION

This study provides further evidence regarding the contribution of education level and physical activity to dementia resilience.

HIGHLIGHTS

Education level, marital status, and physical activity are thought to contribute to resilience against ADRD. We used random-effects meta-analysis to summarize results from six community-based samples from the CCC. In this cross-cohort meta-analysis, higher education level and being physically active were associated with lower risk of dementia. In cross-sectional analyses, being married was associated with larger TBV and HV, while being physically active was associated with larger TBV and lower WMHV.

Perceived risk of Alzheimer's disease: Insights into the Black and African American male perspective

BackgroundNon-Hispanic Black and African American men are more likely to have Alzheimer's disease (AD) than non-Hispanic White peers. Despite this, little is known about how Black and African American men perceive dementia risk, which is foundational to prevention.ObjectiveAcknowledging that personal vantage point influences behavior, our study examined Black and African American male perceptions about their anticipated risk for AD.MethodsWe conducted a secondary analysis of Black and African American adult male responses to the Recruitment Innovations for Diversity Enhancement electronic survey study. We examined associations between perceived risk of AD and age, education, employment status, household income adequacy, marital status, living status, prior experience with AD, and subjective memory performance using generalized linear models.ResultsRespondents (n = 112) were age 18 to 79 years (M = 51.05, SD = 13.44), and 35% reported prior experience with AD through a friend or family member. Respondents' perceived risk of developing AD ranged from 0 to 100% (M = 33.46, SD = 28.29). Spearman rho correlations revealed modest but significant correlations between perceived risk and age (r = 21, p = 0.03) and marital status (r = -0.22 p = 0.02). The best fitting generalized linear model revealed low perceived risk for AD was associated with younger age, income adequacy and being married or living as married (χ2 = 8.76, p = 0.03).ConclusionSelected social determinants of health were associated with perceived risk. Future studies should examine additional social determinants of health (e.g., social and physical environment) and measures of cognitive and physical health to further explore relationships with perceived risk of AD in Black and African American males.

Exploring the association of social isolation and loneliness on the experience of COVID-19 infection and hospitalization in the Japanese population: the JACSIS study

PURPOSE

Social isolation and loneliness have been long-standing public health concerns, and the coronavirus disease 2019 (COVID-19) pandemic has exacerbated these issues. Therefore, this study aimed to investigate the associations of social isolation and loneliness during the pandemic with experience of COVID-19 infection and hospitalization in the Japanese population.

METHODS

Data were sourced from the Japan COVID-19 and Society Internet Survey (JACSIS), a large-scale, web-based national survey of individuals aged 15-79. This study used JACSIS data from 2020 to 2022, representing the first and third years of the pandemic. Social isolation was measured by the frequency of direct and indirect contact with people other than co-residing family members. Loneliness was evaluated using the UCLA Loneliness Scale, while COVID-19 infection and hospitalization were self-reported.

RESULTS

A total of 13,612 individuals were included, of whom 1.5% had experienced hospital admission due to COVID-19, and 9.3% were infected but not hospitalized. Social isolation was inversely associated with COVID-19 infection risk (odds ratio = 0.77; 95% confidence interval: 0.66-0.90), while a higher level of loneliness was related to hospitalization (odds ratio = 2.21; 95% confidence interval: 1.59-3.09). Sex-stratified analyses revealed stronger associations in men than women.

CONCLUSION

This study highlights the complex relationship between psychosocial factors and infectious disease outcomes, underscoring the need for comprehensive approaches to address the multifaceted challenges posed by global health crises.

Social isolation, loneliness, and their joint effects on cognitive decline and incident Alzheimer's disease: Findings from the Chicago health and aging project

BACKGROUND

There has been contradictory evidence on the prospective associations between social isolation/loneliness (SI/L) and cognitive decline (CD). There is also a scarcity of large and diverse population-based cohort studies examining SI/L that have confirmed clinical diagnoses of Alzheimer's Disease (AD). Notably, beyond individual associations, whether the effects of SI/L compound and accelerate CD and incident AD are not known.

OBJECTIVES

We hypothesized that SI and L, independently, would be associated with CD and incident AD to a similar extent, and the association of SI with CD and incident AD would be higher in lonely older adults.

DESIGN

Prospective cohort study.

SETTING

Urban Chicago areas.

PARTICIPANTS

We analyzed data in the Chicago Health and Aging Project (CHAP), which comprised 7,760 biracial community-dwelling older adults [mean age (standard deviation (SD))=72.3 (6.3); 64 % Black & 63 % women; mean (SD) of follow-up=7.9 (4.3) years].

INTERVENTION (IF ANY)

NA MEASUREMENTS: Linear mixed and logistic regression models were used to regress CD and incident AD separately on the SI index/L.

RESULTS

SI index and L were significantly associated with CD, with one-point increase of beta estimate (SE, p-value) = -0.002 (0.001,0.022) and -0.012 (0.003,<0.001), respectively. Given that the SI index ranges from 0 to 5 and the L from 0 to 1, they had similar effect sizes. Similarly, there were significant associations between SI index and incident AD, odds ratio (95 % CI, p-value) = 1.183 (1.016-1.379,0.029), and between L and incident AD, 2.117 (1.227-3.655,0.006). When stratified by loneliness status, compared to older adults who were not isolated and not lonely, older adults who reported being socially isolated and not lonely experienced accelerated CD, -0.003 (0.001,0.004), despite no significantly increased odds of incident AD.

CONCLUSIONS

SI/L had significant associations with CD and incident AD. Notably, socially isolated older adults who reported not being lonely appeared to be most socially vulnerable to CD. These findings suggest a specific at-risk subgroup of socially vulnerable older adults for future targeted interventions to improve cognitive health.

Healthcare providers' perceived importance and barriers to addressing social connection in medical settings

Despite the well-established significance of indicators of social connection for health and mortality, healthcare providers' (HCPs) perceptions of the role of social connection in physical health and the extent to which it is considered medically relevant remain unclear. This study examines the perceived importance and barriers to addressing social connection among HCPs in clinical settings. Surveys were completed by 681 HCPs across multiple locations and medical settings. HCPs ranked social connection low in importance among factors known to influence mortality and chronic illness. Furthermore, HCPs report significant barriers to addressing social connection; including lack of time, resources, training, and confidence. The findings have implications for developing educational programs, institutional policies, and structural changes to facilitate the integration of social connection into clinical practices, ultimately improving patient outcomes and overall public health.

Factors associated with dementia among older people in Malaysia: Findings from National Health and Morbidity Survey

OBJECTIVE

To identify factors associated with dementia among older people in Malaysia.

METHODS

This study used data from a nationwide cross-sectional survey in Malaysia. Participants involved were older people aged 60 years and above. Data collected were on dementia risk factors as well as dementia screening. Dementia screening was done using the Identification and Intervention for Dementia in Elderly Africans cognitive screening tool. Univariate analysis and multiple logistic regression were carried out to determine the factors associated with dementia.

RESULTS

There were 3774 participants involved in this study. Multiple logistic regression showed factors associated with dementia among older people were those aged 70 years and above, Indian ethnic group, being single, primary or no formal education, as well as those with hypertension. Interestingly, our findings also showed that older people with hypercholesterolemia have lower odds of having dementia.

CONCLUSIONS

Multiple factors were associated with dementia in Malaysia, highlighting the need to implement multiple interventions strategies, by taking a lifetime approach emphasizing education, physical as well as social aspects.

The effects of language learning on cognitive functioning and psychosocial well-being in cognitively healthy older adults: A semi-blind randomized controlled trial

This study investigated the impact of language learning in comparison to other complex learning activities on cognitive functioning and psychosocial well-being in cognitively healthy, community-dwelling older adults. In a randomized controlled trial, 43 Dutch functionally monolinguals aged 65-78 completed a three-month English course (n = 15), music training (n = 13), or a lecture series (n = 15). Cognitive functioning (global cognition, cognitive flexibility, episodic memory, working memory, verbal fluency, and attention) and psychosocial well-being were assessed before and immediately after the intervention, and at a four-month follow-up. The language learners significantly improved on episodic memory and cognitive flexibility. However, the magnitude of cognitive change did not significantly differ between the language learning and music training conditions, except for a larger positive change in cognitive flexibility for the language learners from pretest to follow-up. Our results suggest that language learning in later life can improve some cognitive functions and fluency in the additional language, but that its unique effects seem limited.

Blind spots in health perception: the underestimated role of social connection for health outcomes

BACKGROUND

Robust evidence indicates that having few or poor-quality social connections is associated with poorer physical health outcomes and risk for earlier death (Snyder-Mackler N, Science 368, 2020; Vila J, Front Psychol 12:717164, 2021).

AIM

This study sought to determine whether recent attention on social connection and loneliness brought on by the COVID-19 pandemic may influence risk perception and whether these perceptions were heightened among those who are lonely.

METHODS

Two waves of online survey data were collected. The first included data from 1,486 English-speaking respondents in the US, UK, and Australia, and a second sample of 999 nationally representative US adults, with a final sample of 2392 respondents from the US and UK.

RESULTS

Perceptions of risk have remained consistent, underestimating the influence of social factors on health outcomes and longevity, even among respondents who reported moderate-to-severe levels of loneliness.

CONCLUSIONS

Despite heightened awareness and discourse during the COVID-19 pandemic, public perception in the US and UK continues to significantly underestimate the impact of social factors on physical health and mortality. This underestimation persists regardless of individual loneliness levels, underscoring the need for enhanced public education and policy efforts to recognize social connection as a crucial determinant of health outcomes.

Association of a novel nutritional index with cognitive impairment in middle-aged and elderly Chinese adults: a cross-sectional analysis from the China Health and Retirement Longitudinal Study

Purpose

The triglyceride-cholesterol-body weight index (TCBI), a novel and easily computable nutritional index, incorporates serum triglyceride (TG), total cholesterol (TC), and body weight (BW). This study explored the association between TCBI and cognitive impairment in middle-aged and elderly Chinese populations.

Patients and methods

This cross-sectional study employed data from the China Health and Retirement Longitudinal Study (CHARLS) baseline survey, including 7,145 participants. TCBI was calculated as TG (mg/dL) × TC (mg/dL) × BW (kg)/1,000. Cognitive function was assessed based on mental status and episodic memory, with a total score below 11 indicating cognitive impairment. The relationship between TCBI and cognitive impairment was examined using multiple logistic regression, smooth curve fitting, and subgroup analyses.

Results

After full adjustment, each 1-unit increase in log-transformed TCBI (Lg TCBI) was associated with a 29.7% reduction in cognitive impairment risk [odds ratio (OR) = 0.703, 95% confidence interval (CI): 0.529-0.933; p = 0.015]. When Lg TCBI was categorized into quartiles, the Q2, Q3, and Q4 groups exhibited a reduced risk of cognitive impairment by 19.9, 16.3, and 22.9%, respectively (p for trend = 0.043), compared to the Q1 group. Smooth curve fitting revealed a consistent decrease in cognitive impairment risk with higher Lg TCBI levels. Subgroup analysis indicated that the association was stronger among participants aged ≥60 years (OR = 0.655, 95% CI: 0.438-0.979), non-current drinkers (OR = 0.643, 95% CI: 0.451-0.917), and those who engaged in socializing (OR = 0.568, 95% CI: 0.371-0.871).

Conclusion

TCBI was significantly and negatively associated with cognitive impairment in Chinese middle-aged and elderly individuals, with the effect more pronounced in those aged ≥60 years, non-current drinkers, and socially active participants.

Neuroanatomical and clinical factors predicting future cognitive impairment

Identifying cognitively normal (CN) older adults who will convert to cognitive impairment (CI) due to Alzheimer's disease is crucial for early intervention. Clinical and neuroimaging measures were acquired from 301 CN adults who converted to CI within 15 years of baseline, and 294 who did not. Regional volumes and brain age measures were extracted from T1-weighted magnetic resonance images. Linear discriminant analysis compared non-converters' characteristics against those of short-, mid-, and long-term converters. Conversion was associated with clinical measures such as hearing impairment and self-reported memory decline. Converters' brain volumes were smaller than non-converters' across 48 frontal, temporal, and subcortical structures. Brain age measures of 12 structures were correlated with shorter times to conversion. Conversion prediction accuracy increased from 81.5% to 90.5% as time to conversion decreased. Proximity to CI conversion is foreshadowed by anatomic features of brain aging that enhance the accuracy of predicting conversion.

Protein signatures associated with loneliness and social isolation: Plasma proteome analyses in the English Longitudinal Study of Ageing, with causal evidence from Mendelian randomization

INTRODUCTION

The understanding of biological pathways related to loneliness and social isolation remains incomplete. Cutting-edge population-based proteomics offers opportunities to uncover novel biological pathways linked to social deficits.

METHODS

This study employed a proteome-wide and data-driven approach to estimate the cross-sectional associations between objective measures of social connections (i.e., social isolation) and subjective measures (i.e., loneliness) with protein abundance, using the English Longitudinal Study of Ageing.

RESULTS

Greater social isolation was associated with higher levels of 11 proteins (TNFRSF10A, MMP12, TRAIL-R2, SKR3, TNFRSF11A, VSIG2, PRSS8, FGFR2, KIM1, REN, and NEFL) after minimal adjustments; and three proteins were significantly associated after full adjustments (TNFRSF10A, TNFRSF11A, and HAOX1). Findings from two-sample Mendelian randomization indicated that a lower frequency of in-person social contact with friends or family causally increased levels of TNFRSF10A, TRAIL-R2, TNFRSF11A, and KIM1, and decreased the level of NEFL. The study also highlighted several enriched biological pathways, including necrosis and cell death regulation, dimerization of procaspase-8, and inhibition of caspase-8 pathways, which have previously not been linked to social deficits.

CONCLUSION

These findings could help explain the relationship between social deficits and disease, confirming the importance of continuing to explore novel biological pathways associated with social deficits.

Impact of social isolation on change in brain volume in community-dwelling older Japanese people: The NEIGE Study

BACKGROUND

Several studies have shown that social isolation is a risk factor for cognitive decline and dementia; however, its neurological mechanisms are not fully understood. Using longitudinal data, this study examined the effects of social isolation on hippocampal and total gray matter volumes in community-dwelling older Japanese individuals.

METHODS

Data were obtained from the Neuron to Environmental Impact Across Generations (NEIGE) Study conducted in Tokamachi City (Niigata Prefecture, Japan), including 279 community-dwelling persons aged 65-84 years who underwent brain magnetic resonance imaging in 2017 and 2021 (male: 47.6 %; mean age: 73.0 years). We investigated two dimensions of social isolation: poor social networks and solitary living.

RESULTS

Multiple regression analysis with inverse probability weighting showed that individuals with a social contact frequency of <1 time/week had a greater decrease in hippocampal volume than those with a contact frequency of more than or equal to 4 times/week, whereas those who lived alone tended to have a smaller decrease in hippocampal volume than those who lived with others. We found no association between the frequency of social contact, living alone, and total gray matter volume. Furthermore, there was no interaction between sex and age for any of the outcomes.

CONCLUSION

Our longitudinal analysis suggested that the relationship between social isolation and dementia onset may be mediated by hippocampal atrophy; however, the direction of the influence depends on the isolation type. These findings are expected to contribute to the elucidation of the social mechanisms underlying dementia onset.

Alzheimer's disease: insights into pathology, molecular mechanisms, and therapy

Alzheimer's disease (AD), the leading cause of dementia, is characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. This condition casts a significant shadow on global health due to its complex and multifactorial nature. In addition to genetic predispositions, the development of AD is influenced by a myriad of risk factors, including aging, systemic inflammation, chronic health conditions, lifestyle, and environmental exposures. Recent advancements in understanding the complex pathophysiology of AD are paving the way for enhanced diagnostic techniques, improved risk assessment, and potentially effective prevention strategies. These discoveries are crucial in the quest to unravel the complexities of AD, offering a beacon of hope for improved management and treatment options for the millions affected by this debilitating disease.

Associations of modifiable dementia risk factors with dementia and cognitive decline: evidence from three prospective cohorts

Objective

This study aims to assess the relationship between modifiable dementia risk factors and both dementia and cognitive decline.

Methods

Data were obtained from the Health and Retirement Study (HRS) [2008-2020], the China Health and Retirement Longitudinal Study (CHARLS) [2011-2020], and the English Longitudinal Study of Ageing (ELSA) [2010-2020]. After adjusting for confounding factors, multivariable logistic regression was utilized to analyze the relationship between modifiable dementia risk factors and dementia, while multivariable linear regression was employed to examine the relationship between these risk factors and cognitive decline. Additionally, the Cox proportional hazards model was used to assess the relationship between the number of risk factor events, clusters, and dementia risk.

Results

A total of 30,113 participants from HRS, CHARLS, and ELSA were included (44.6% male, mean age 66.04 years), with an average follow-up period of 7.29 years. A low education level was significantly associated with an increased risk of dementia and accelerated cognitive decline (Overall, OR = 2.93, 95% CI: 2.70-3.18; Overall, β = -0.25, 95% CI: -0.60 to-0.55). The presence of multiple dementia risk factors correlated with a higher dementia risk; Specifically, compared with more than 5 risk factor events, both having no dementia risk factors and having only one dementia risk factor were associated with a significantly lower risk of dementia (Overall, HR = 0.15, 95% CI: 0.11-0.22, HR = 0.22, 95% CI: 0.18-0.25). Compared to the group with no coexistence of risk factors, the clusters of excessive alcohol, diabetes, vision loss, and hearing loss (HR = 4.11; 95% CI = 3.42-4.95; p < 0.001); excessive alcohol, vision loss, smoking, and hearing loss (HR = 5.18; 95% CI = 4.30-6.23; p < 0.001); and excessive alcohol, obesity, diabetes, and smoking (HR = 5.96; 95% CI = 5.11-6.95; p < 0.001) were most strongly associated with dementia risk.

Conclusion

Among the 11 risk factors, educational attainment has the greatest impact on dementia risk and cognitive decline. A dose-response relationship exists between the number of modifiable risk factor events and dementia risk. The coexistence of multiple risk factors is associated with dementia risk, and these associations vary by risk factor cluster.

Typology of Social Participation and Network and Health in Older Adults: Results From the Canadian Longitudinal Study on Aging

This study aimed to document the typology of social participation and network among older Canadians and examine their associations with health. Using 2011-2015 cross-sectional data from the Canadian Longitudinal Study on Aging, a latent profile analysis was conducted to identify patterns of social participation and network, and multinomial logistic regressions examined associations with self-rated health. Four types of social participation and networks characterized older Canadians: diverse (74.0%), childless (12.1%), restricted (9.7%), and very socially active (4.3%). Compared to the diverse group and excellent/very good health, belonging to the restricted group was associated with higher probabilities of reporting fair or poor health, both general (1.95; p < .001) and mental (2.18; p < .001). Still comparing to the diverse group and excellent/very good health, the very socially active group presented lower likelihood of reporting good general health (0.82; p = .03). These results suggest that the social participation and network are associated with health inequalities in older Canadians. Future studies should look at the role of virtual interactions in the health of older adults.

Effects of Wisdom-Enhancement Narrative-Therapy and Empathy-Focused interventions on loneliness over 4 weeks among older adults: A Randomized Controlled Trial

OBJECTIVE

In this three-armed RCT, we tested the effects of a telephone-delivered wisdom enhancement narrative therapy-based intervention (Tele-NT) and a telephone-delivered empathy-focused intervention (Tele-EP) in reducing loneliness against an active control group that received regular call (ACG) at the 4-week follow-up assessment.

DESIGN, SETTING, INTERVENTION, AND PARTICIPANTS

To evaluate the effects of the interventions on loneliness, we randomized 287 older adults based in Hong Kong, ages 65 to 90, into Tele-NT (N = 97), Tele-EP (N = 95), or ACG (N = 95).

MEASUREMENT

The primary outcome was loneliness, calculated using the De Jong Gierveld Scale and the UCLA Loneliness Scale. Secondary outcomes were sleep quality, depressive symptoms, social network engagement, and perceived social support. Assessments were done before training and 4 weeks after the intervention period.

RESULTS

Results from linear mixed models showed significant positive effects of Tele-NT on loneliness measured by the De Jong Gierveld Loneliness Scale compared to ACG. Compared to the ACG, the Tele-NT group significantly reduced loneliness at the 4-week follow-up (mean difference = -0.51, p = 0.019, Cohen's d = 0.60). However, the difference between Tele-EP and the ACG at the 4-week follow-up was not significant (MD = -0.34, p = 0.179, Cohen's d = 0.49). Tele-NT and Tele-EP did not show significant effects on the secondary outcomes, compared to the ACG.

CONCLUSIONS

In this randomized clinical trial, we found that a 4-week wisdom enhancement narrative therapy program significantly reduced feelings of loneliness. This effective telephone-based, lay-therapist-delivered program is scalable for broader implementation.

Systematic review of what people know about brain health

OBJECTIVES

As we age our cognitive abilities can change. However, the degree of change experienced is influenced by a range of factors. To understand what the public know about risk and protective factors for cognitive ageing, a systematic review was conducted of studies considering what people know about brain health.

METHOD

The search strategy included quantitative and qualitative studies in English, including interviews, focus groups, questionnaires, surveys of beliefs about brain health (including predictions, opinions) in generally healthy adults. PubMed, PsycINFO, Scopus, and Web of Science were used for published peer-reviewed literature; and ProQuest Dissertations and Theses and National Grey Literature Collection, PsycExtra and Google searches for grey literature.

RESULTS

From 37,197 records, one hundred and one were included, comprising 71 quantitative (22 grey literature), 27 qualitative (1 grey literature) and 3 mixed-methods (1 grey literature). Studies were grouped into three themes: Concerns about cognitive ageing, Opportunities to promote brain health and Understanding dementia risk reduction and prevention.

DISCUSSION

Studies reported varying levels of knowledge of brain health, alongside some suggestions for brain health that were somewhat superficial and not always consistent with scientific consensus. There were differences between groups of participants who exhibited less knowledge of brain health, for example, men, older adults, those with lower education and incomes, and ethnic minorities. This review highlights the need for clear messaging around opportunities to promote brain health, including scientifically-endorsed lifestyle factors and more information on the mechanisms by which they operate.

Late-life social activity and subsequent risk of dementia and mild cognitive impairment

INTRODUCTION

Social activity is associated with better cognitive health in old age. To better translate epidemiological research for public health communication, we estimated relations of levels of social activity to average age at dementia onset.

METHODS

In the Rush Memory and Aging Project (MAP), we followed 1923 dementia-free older adults and conducted annual clinical evaluations of dementia/mild cognitive impairment (MCI).

RESULTS

During a mean follow-up of 6.7 (SD = 4.7) years, 545 participants developed dementia, and 695 developed MCI. Using Accelerated Failure Time models adjusted for age, sex, education, race/ethnicity, and marital status, we found predicted mean age of dementia onset for the least socially active was 87.7 years, approximately 5 years earlier than the most socially active (mean age = 92.2, p < .01); we found a similar 5-year difference in age at MCI onset by social activity.

DISCUSSION

Our findings highlight the value of social activity as a possible community-level intervention for reducing dementia.

HIGHLIGHTS

Accelerated failure time models estimated age at dementia onset by social activity level to aid interpretation. Higher social activity was associated with a 5-year older age at dementia onset. Economic research shows a 5-year delay translates to US$500,000 of healthcare savings per capita. Our findings help understand the public health significance of social activity.

Internet-Based Social Activities and Cognitive Functioning 2 Years Later Among Middle-Aged and Older Adults: Prospective Cohort Study

Background

A number of studies document the benefits of face-to-face social interactions for cognitive functioning among middle-aged and older adults. Social activities in virtual worlds may confer similar if not enhanced cognitive benefits as face-to-face social activities, given that virtual interactions require the additional cognitive tasks of learning and navigating communicative tools and technology platforms. Yet, few studies have examined whether social activities in internet-based settings may have synergistic effects on cognitive functioning beyond those of face-to-face interactions.

Objective

This study examined whether internet-based social activity participation is associated with concurrent and later cognitive functioning, after adjusting for face-to-face social activity participation and sociodemographic covariates.

Methods

For cross-sectional analyses, we included 3650 adults aged 50 years and older who completed questions in the 2020 Health and Retirement Study about social activity participation, including specific internet-based social activities such as emailing or accessing social networks. Cognitive functioning was measured using the standardized cognitive tasks assessing working memory, episodic memory, and attention and processing speed. The longitudinal analyses included the 2034 participants who also completed follow-up cognitive assessments in 2022.

Results

Our results revealed that those with higher levels of internet-based social activity participation had higher levels of concurrent cognitive functioning than those with low levels of internet-based social activity participation, after adjusting for demographic and health-related factors and face-to-face social activity participation (b=0.44, SE 0.07; P<.001). More internet-based social activity participation also predicted better cognitive functioning 2 years later, even when adjusting for baseline cognitive functioning and other covariates (b=0.35, SE 0.09; P<.001).

Conclusions

Our findings suggest that greater engagement in internet-based social activities is associated with higher levels of concurrent cognitive functioning and slower cognitive decline in middle-aged and older adults.

Sex differences in loneliness, social isolation, and their impact on psychiatric symptoms and cognitive functioning in schizophrenia

BACKGROUND

Social isolation and loneliness, objective and subjective features of dysfunctional social relationships, are more prevalent in patients with schizophrenia (SCZ) than in the general population. This study aimed to explore sex differences in loneliness and social isolation among Chinese chronic SCZ patients, and to investigate their relationships with psychiatric symptoms and cognitive functioning.

METHODS

A total of 323 SCZ patients, comprising 136 males and 187 females, were recruited. Psychopathology, cognitive functioning, loneliness, social isolation were assessed using the Positive and Negative Syndrome Scale (PANSS), the Repeated Battery for Assessment of Neuropsychological Status (RBANS), the UCLA (University of California, Los Angeles) Loneliness Scale (Version 3) and the Social Isolation Index (ISI). Multiple linear regression models were conducted to test the independent, relative, and synergistic efects of loneliness and social isolation on psychiatric symptoms and cognitive performance for male and female patients separately.

RESULTS

Male patients exhibited higher UCLA loneliness scale scores and social isolation scores compared to female patients (ps < 0.05). In male patients, both loneliness and social isolation significantly predicted PANSS total scores (ps< 0.01), negative subscale scores (ps < 0.05) and general psychopathology subscale scores (ps < 0.05). For female patients, loneliness (not social isolation) significantly predicted immediate memory (p < 0.001), language (p = 0.013), delayed memory (p = 0.017), and RBANS total scores (p = 0.002). Further examination of loneliness components in female patients revealed that personal feelings of isolation were negatively associated with language (r = -0.21, p = 0.001) and a negative correlation exists between lack of collective connectedness and delayed memory (r = -0.19, p = 0.048).

CONCLUSION

Loneliness and social isolation are more pronounced in male SCZ patients than in female patients. Both loneliness and social isolation are positively related to psychiatric symptoms in male patients, while loneliness is negatively associated with cognitive functioning in female patients.

The Assessment of Social Isolation and Loneliness in Cancer Patients and Survivors in the Pre-COVID-19 Period: A Systematic Review

BACKGROUND

In the context of cancer research, identifying social isolation and loneliness is a priority given how both exacerbate poor outcomes and lead to increased mortality in oncological populations. The purpose of this systematic review is to identify all quantitative instruments that have been used to assess either social isolation or loneliness in patients previously or currently diagnosed with cancer in the pre-COVID-19 period.

METHOD

PubMed (Web), Scopus, CINAHL, and PsycINFO were searched on August 22, 2019. All databases were searched from inception with no filters applied. The search strategies included terms that captured the following concepts: instruments/tools, social isolation or loneliness, and cancer.

RESULTS

A total of 289 titles/abstracts were returned. Upon review, 114 titles/abstracts were deemed to be potentially eligible and the full text was retrieved. Of the 114 full texts, 69 articles met inclusion criteria and comprised the final sample. Publications span years 1980 through 2019, with the majority (71%) occurring in the last decade prior to this review, between 2009 and 2019. Average age of the study samples, with few exceptions, was often over 50 years old. Many studies used all-female samples, while only one study used an all-male sample. The most common cancer diagnosis of participants was breast cancer. The most common measure was the UCLA Loneliness Scale, used in 22 studies. Most measures we identified were used only once, and 11 measures were used 2-3 times. When the information was given, response ranges were always Likert-type scales most often ranging from 1-4 or 1-5, and sometimes from 1-10 possible response options. In terms of psychometrics, test-retest reliability and validity were rarely reported; by contrast, internal consistency (Cronbach's alpha) was reported more than half of the time (60.9%).

CONCLUSION

When selecting a measure to assess loneliness in cancer populations, the UCLA Loneliness Scale is both psychometrically strong and versatile across patients with different cancers, ages, and racial backgrounds. When selecting a measure to assess social isolation in cancer populations, both the PROMIS-SF V 2.0 social isolation and the Berkman-Syme Network Index are brief and have been used in patients with non-White racial backgrounds.

Associations between recorded loneliness and adverse mental health outcomes among patients receiving mental healthcare in South London: a retrospective cohort study

PURPOSE

Loneliness disproportionately affects people with mental disorders, but associations with mental health outcomes in groups affected remain less well understood.

METHOD

A cohort of patients receiving mental healthcare on 30th June 2012 was assembled from a large mental health records database covering a south London catchment area. Recorded loneliness within the preceding 2 years was extracted using natural language processing and outcomes were measured between 30th June 2012 until 30th December 2019, except for survival which applied a censoring point of 6th December 2020 according to data available at the time of extraction. The following mental healthcare outcomes: (i) time to first crisis episode; (ii) time to first emergency presentation; (iii) all-cause mortality; (iv) days active to service per year; and (v) face-to-face contacts per year.

RESULTS

Loneliness was recorded in 4,483 (16.7%) patients in the study population and fully adjusted models showed associations with subsequent crisis episode (HR 1.17, 95% CI 1.07-1.29), emergency presentation (HR 1.30, 1.21-1.40), days active per year (IRR 1.04, 1.03-1.05), and face-to-face contacts per year (IRR 1.28, 1.27-1.30). Recorded loneliness in patients with substance misuse problems was particularly strongly associated with adverse outcomes, including risk of emergency presentation (HR 1.68, 1.29-2.18) and mortality (HR 1.29, 1.01-1.65).

CONCLUSION

Patients receiving mental healthcare who are recorded as lonely have a higher risk of several adverse outcomes which may require a need for higher service input.

Mobility-Based Smartphone Digital Phenotypes for Unobtrusively Capturing Everyday Cognition, Mood, and Community Life-Space in Older Adults: Feasibility, Acceptability, and Preliminary Validity Study

BACKGROUND

Current methods of monitoring cognition in older adults are insufficient to address the growing burden of Alzheimer disease and related dementias (AD/ADRD). New approaches that are sensitive, scalable, objective, and reflective of meaningful functional outcomes are direly needed. Mobility trajectories and geospatial life space patterns reflect many aspects of cognitive and functional integrity and may be useful proxies of age-related cognitive decline.

OBJECTIVE

We investigated the feasibility, acceptability, and preliminary validity of a 1-month smartphone digital phenotyping protocol to infer everyday cognition, function, and mood in older adults from passively obtained GPS data. We also sought to clarify intrinsic and extrinsic factors associated with mobility phenotypes for consideration in future studies.

METHODS

Overall, 37 adults aged between 63 and 85 years with healthy cognition (n=31, 84%), mild cognitive impairment (n=5, 13%), and mild dementia (n=1, 3%) used an open-source smartphone app (mindLAMP) to unobtrusively capture GPS trajectories for 4 weeks. GPS data were processed into interpretable features across categories of activity, inactivity, routine, and location diversity. Monthly average and day-to-day intraindividual variability (IIV) metrics were calculated for each feature to test a priori hypotheses from a neuropsychological framework. Validation measures collected at baseline were compared against monthly GPS features to examine construct validity. Feasibility and acceptability outcomes included retention, comprehension of study procedures, technical difficulties, and satisfaction ratings at debriefing.

RESULTS

All (37/37, 100%) participants completed the 4-week monitoring period without major technical adverse events, 100% (37/37) reported satisfaction with the explanation of study procedures, and 97% (36/37) reported no feelings of discomfort. Participants' scores on the comprehension of consent quiz were 97% on average and associated with education and race. Technical issues requiring troubleshooting were infrequent, though 41% (15/37) reported battery drain. Moderate to strong correlations (r≥0.3) were identified between GPS features and validators. Specifically, individuals with greater activity and more location diversity demonstrated better cognition, less functional impairment, less depression, more community participation, and more geospatial life space on objective and subjective validation measures. Contrary to predictions, greater IIV and less routine in mobility habits were also associated with positive outcomes. Many demographic and technology-related factors were not associated with GPS features; however, income, being a native English speaker, season of study participation, and occupational status were related to GPS features.

CONCLUSIONS

Theoretically informed digital phenotypes of mobility are feasibly captured from older adults' personal smartphones and relate to clinically meaningful measures including cognitive test performance, reported functional decline, mood, and community activity. Future studies should consider the impact of intrinsic and extrinsic factors when interpreting mobility phenotypes. Overall, smartphone digital phenotyping is a promising method to unobtrusively capture relevant risk and resilience factors in the context of aging and AD/ADRD and should continue to be investigated in large, diverse samples.

Instruments for assessing social health in the context of cognitive decline and dementia: a systematic review

The concept of social health has recently received increasing attention in dementia research. Various notions of what social health is and how it can be measured are circulating. They may pose challenges for comparing results and interpreting them for the development of interventions. This systematic review aims to classify existing instruments that measure various domains of social health. To achieve this, we applied a new multidimensional framework consisting of six key domains of social health. A systematic review was conducted following the PRISMA 2020 guidelines. PubMed/MEDLINE, PsychINFO, and CINAHL were searched for studies published between January 2000 and July 2023. A total of 227 studies (longitudinal, case-control, and cross-sectional cohort studies) with 102 single instruments were included. The search terms were as follows: (1) dementia (i.e., Alzheimer's, cognitive impairment); (2) social health markers (i.e., decision-making, social participation, loneliness); and (3) instruments (i.e., tools, measures). The instruments are mainly self-reported, and the number of items ranges from 3 to 126. Despite the wide array of instruments available, most focus on individual domains of social health. We recommend the development of more conceptually robust instruments that can comprehensively evaluate psychosocial interventions and adequately capture all domains of social health.

Impact of remote social interaction during the COVID-19 pandemic on the cognitive and psychological status of older adults with and without cognitive impairment: A randomized controlled study

BACKGROUND

Social isolation and loneliness have both been associated with psychological health and cognitive decline in older adults. This study investigated the impact of social interaction through remote communication technologies during the COVID-19 pandemic on the cognitive and psychological status of older adults with and without cognitive impairment.

METHODS

Participants were recruited from Boston (USA) and Chieti (Italy). The study used a randomized single-blinded controlled crossover design with an intervention (remote social conversations with research staff over 20-minute video or telephone calls three times per week) and a passive control condition, each one of 4-weeks duration. The primary outcome was a composite cognitive score change from baseline to week 4. Secondary outcomes included scales for mood, anxiety, and loneliness.

RESULTS

Out of 196 participants recruited from April 2020 to April 2021, 17% dropped out. Based on the blind MoCA, 52% had cognitive impairment, and 25% were at risk of social isolation according to the Lubben social network scale. We observed that larger social networks were linked to better cognitive status and lower depression and anxiety levels, while loneliness was directly associated to depression severity. Older adults with cognitive impairment exhibited higher levels of depression and anxiety and were at greater risk for social isolation. In terms of the intervention, 91% preferred telephone over video calls. The intervention did not lead to improvements in cognitive or psychological scores.

CONCLUSIONS

More work is needed to assess the utility of this intervention for the support of a heterogenous cross-cultural sample of older adults at-risk for social isolation, including individuals with cognitive impairment. Future research should explore longer intervention periods, categorize participants by call type, and target those meeting social isolation criteria.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04480112.

A community-academic partnered approach to designing a Virtual Village to address the needs of older adults living with HIV

ABSTRACTMany older adults living with HIV face unique challenges, including comorbidities, loneliness, and isolation. This community-academic partnered study elicited viewpoints from older adults living with HIV about the characteristics of a digital environment ("Virtual Village") to combat against loneliness and isolation. We utilized Choice-Based Conjoint Analyses to determine preferred attributes of a Virtual Village. We also conducted focus groups and interviews with older adults living with HIV and used an iterative, data-driven approach to systematically identify emergent themes. Participants (N = 82) were aged 50-82 years and racially/ethnically diverse. The majority were men (78%), gay (66%), and lived with HIV for ≥15 years (83%). Cost was the factor that most drove participants' preference for joining a Virtual Village. Thematic concerns included lack of technological confidence, internet access, potential for harassment in digital environments, privacy, and preference for in-person interactions. Praises centered on convenience and making connections across geographic distances. Participants emphasized the need for purposive strategies to form a cohesive and supportive community for older adults living with HIV. A moderated environment was recommneded to create a safe, structured, and comfortable digital environment for older adults living with HIV. A Virtual Village should be viewed as a bridge to in-person interactions.

Social cohesion as a modifier of joint air pollution exposure and incident dementia

Social cohesion can reduce stress, increase social interaction, and improve cognitive reserve. These social mechanisms may modify the effects of air pollution on dementia risk. This cohort study examines the potential moderating effect of social cohesion on associations between joint air pollution exposure and incident dementia leveraging data from 5112 community-dwelling adults ≥65 years of age enrolled in the National Health and Aging Trends Study (NHATS). Study participants were enrolled in 2011 and followed through 2018. We assigned 2010 residential census tract-level exposures to five air pollutants, particulate matter (PM) ≤ 10 μm in diameter, PM ≤ 2.5 μm in diameter, carbon monoxide, nitric oxide, and nitrogen dioxide, using the US Environmental Protection Agency's Community Multiscale Air Quality Modeling System. Dementia status was determined based on self- or proxy-reported dementia diagnosis or "probable dementia" according to NHATS cognitive screening tools. Participants' self-rated neighborhood social cohesion was evaluated based on three questions: neighbors knowing each other, being helpful, and being trustworthy. Social cohesion was dichotomized at the median into high vs low social cohesion. Associations between air pollutants and incident dementia were assessed using quantile g-computation Cox proportional hazard models and stratified by high vs low social cohesion, adjusting for age, sex, education, partner status, urbanicity, annual income, race and ethnicity, years lived at current residence, neighborhood disadvantage index, and tract segregation. High social cohesion (HR = 1.20, 95 % CI = 0.98, 1.47) and air pollution (HR = 1.08, 95 % CI = 0.92, 1.28) were not associated with incident dementia alone. However, when stratified, greater joint air pollution exposure increased dementia risk among participants at low (HR = 1.34, 95 % CI = 1.04, 1.72), but not high (HR = 1.00, 95 % CI = 0.93, 1.06) social cohesion. Air pollution was a risk factor for dementia only when reported social cohesion was low, suggesting that social interaction may play a protective role, mitigating dementia risk via air pollution exposure.

Racial Differences in the Association Between Loneliness and Cognitive Impairment Among Older Black and White Men

BACKGROUND

Loneliness is a biopsychosocial stressor linked to poor health outcomes including dementia. Few studies have focused on this association among men and even fewer have examined racial disparities in loneliness and cognitive functioning among this group. The purpose of this study was to examine racial differences in the association between loneliness and cognitive functioning among men in the 2016 wave of the Health and Retirement Study.

METHODS

This cross-sectional study included Black and White men who completed the core questionnaire and the Leave Behind Questionnaire (n = 2 227). Any cognitive impairment was the primary outcome and was measured by a dichotomous variable derived from a modified version of the Telephone Interview for Cognitive Status. Loneliness was the primary independent variable and was derived from the 3-item University of California, Los Angeles (UCLA) Loneliness Scale. Modified Poisson regression models with robust standard errors were estimated to generate prevalence ratios (PRs) and corresponding 95% confidence intervals (CIs).

RESULTS

Black men comprised 18.4% of the study sample; however, the proportion of this group with scores indicating cognitive impairment (35.9%) doubled the corresponding percentage of white men (17.6%). Findings from race-stratified modified Poisson regression models indicated that loneliness was associated with a higher prevalence of any cognitive impairment for White men (PR = 1.24, CI: 1.05-1.47), but not for Black men (PR = 0.92, CI: 0.73-1.16).

CONCLUSIONS

Our results underscore the complexity of race when investigating the association between loneliness and cognitive impairment among older men. Additional studies are needed to further examine how loneliness may have racially distinct implications for cognitive outcomes among the population.

Dementia: Common Syndromes and Modifiable Risk and Protective Factors

Dementia is an umbrella term for multiple conditions that lead to progressive cognitive decline and impaired activities of daily living. Neuropsychological evaluation is essential for characterizing the distinct cognitive and behavioral profile that can aid in the diagnostic process and treatment planning for dementia. Modifiable risk factors for dementia such as nutrition, physical activity, sleep, cognitive and social engagement, and stress provide important avenues for prevention. Neurologists and other health care providers can help patients reduce their risk for dementia by providing them with education about modifiable factors and connecting them to resources to empower them to engage in brain-healthy behavior.

Racial and ethnic disparities in social isolation and 11-year dementia risk among older adults in the United States

AIMS

Social isolation has been implicated in the development of cognitive impairment, but research on this association remains limited among racial-ethnic minoritized populations. Our study examined the interplay between social isolation, race-ethnicity and dementia.

METHODS

We analyzed 11 years (2011-2021) of National Health and Aging Trends Study (NHATS) data, a prospective nationally representative cohort of U.S. Medicare beneficiaries aged 65 years and older. Dementia status was determined using a validated NHATS algorithm. We constructed a longitudinal score using a validated social isolation variable for our sample of 6,155 community-dwelling respondents. Cox regression determined how the interaction between social isolation and race-ethnicity was associated with incident dementia risk.

RESULTS

Average longitudinal frequency of social isolation was higher among older Black (27.6%), Hispanic (26.6%) and Asian (21.0%) respondents than non-Hispanic White (19.1%) adults during the 11-year period (t = -7.35, p < .001). While a higher frequency of social isolation was significantly associated with an increased (approximately 47%) dementia risk after adjusting for sociodemographic covariates (adjusted hazard ratio [aHR] = 1.47, 95% CI [1.15, 1.88], p < .01), this association was not significant after adjusting for health covariates (aHR = 1.21, 95% CI [0.96, 1.54], p = .11). Race-ethnicity was not a significant moderator in the association between social isolation and dementia.

CONCLUSIONS

Older adults from racial-ethnic minoritized populations experienced a higher longitudinal frequency of social isolation. However, race-ethnicity did not moderate the positive association observed between social isolation and dementia. Future research is needed to investigate the underlying mechanisms contributing to racial-ethnic disparities in social isolation and to develop targeted interventions to mitigate the associated dementia risk.

Life-Course Multidisciplinary Psychosocial Predictors of Dementia Among Older Adults: Results From the Health and Retirement Study

Background and Objectives

Identifying predictors of dementia may help improve risk assessments, increase awareness for risk reduction, and identify potential targets for interventions. We use a life-course psychosocial multidisciplinary modeling framework to examine leading predictors of dementia incidence.

Research Design and Methods

We use data from the Health and Retirement Study to measure 57 psychosocial factors across 7 different domains: (i) demographics, (ii) childhood experiences, (iii) socioeconomic conditions, (iv) health behaviors, (v) social connections, (vi) psychological characteristics, and (vii) adverse adulthood experiences. Our outcome is dementia incidence (over 8 years) operationalized using Langa-Weir classification for adults aged 65+ years who meet criteria for normal cognition at the baseline when all psychosocial factors are measured (N = 1 784 in training set and N = 1 611 in testing set). We compare the standard statistical method (Logistic regression) with machine learning (ML) method (Random Forest) in identifying predictors across the disciplines of interest.

Results

Standard and ML methods identified predictors that spanned multiple disciplines. The standard statistical methods identified lower education and childhood financial duress as among the leading predictors of dementia incidence. The ML method differed in their identification of predictors.

Discussion and Implications

The findings emphasize the importance of upstream risk and protective factors and the long-reaching impact of childhood experiences on cognitive health. The ML approach highlights the importance of life-course multidisciplinary frameworks for improving evidence-based interventions for dementia. Further investigations are needed to identify how complex interactions of life-course factors can be addressed through interventions.

Associations of socioeconomic status and healthy lifestyle with incident dementia and cognitive decline: two prospective cohort studies

Background

Little is known about the complex associations of socioeconomic status (SES) and healthy lifestyle with cognitive dysfunction.

Methods

Using data from the Health and Retirement Study (HRS) [2008-2020] and the English Longitudinal Study of Ageing (ELSA) [2004-2018], SES was constructed by latent class analysis using education level, total household income and wealth. Overall healthy lifestyle was derived using information on never smoking, low to moderate alcohol consumption (drinks/day: (0, 1] for women and (0, 2] for men), top tertile of physical activity, and active social contact.

Findings

A total of 12,437 and 6565 participants from the HRS and ELSA were included (40.8% and 46.0% men and mean age 69.3 years and 65.1 years, respectively). Compared with participants of high SES, those of low SES had higher risk of incident dementia (hazard ratio 3.17, 95% confidence interval 2.72-3.69 in the HRS; 1.43, 1.09-1.86 in the ELSA), and the proportions mediated by overall lifestyle were 10.4% (7.3%-14.6%) and 2.7% (0.5%-14.0%), respectively. Compared with participants of high SES and favorable lifestyle, those with low SES and unfavorable lifestyle had a higher risk of incident dementia (4.27, 3.40-5.38 in the HRS; 2.02, 1.25-3.27 in the ELSA) and accelerated rate of global cognitive decline (β = -0.058 SD/year; 95% CI: -0.073, -0.043 in the HRS; β = -0.049 SD/year; 95% CI: -0.063, -0.035 in the ELSA).

Interpretation

Unhealthy lifestyle only mediated a small proportion of the socioeconomic inequality in dementia risk in both US and UK older adults.

Funding

This work was supported by grants from the National Natural Science Foundation of China (82088102 and 82370819), the National Key R&D Program of China (2023YFC2506700), the Shanghai Municipal Government (22Y31900300), the Shanghai Clinical Research Center for Metabolic Diseases (19MC1910100), the Innovative Research Team of High-Level Local Universities in Shanghai, the Special Project for Clinical Research in Health Industry of Shanghai Municipal Health Commission (202340084), and Ruijin Hospital Youth Incubation Project (KY20240805). Y.X. is supported by the National Top Young Talents program.

Genomic Insights into Dementia: Precision Medicine and the Impact of Gene-Environment Interaction

The diagnosis, treatment, and management of dementia provide significant challenges due to its chronic cognitive impairment. The complexity of this condition is further highlighted by the impact of gene-environment interactions. A recent strategy combines advanced genomics and precision medicine methods to explore the complex genetic foundations of dementia. Utilizing the most recent research in the field of neurogenetics, the importance of precise genetic data in explaining the variation seen in dementia patients can be investigated. Gene-environment interactions are important because they influence genetic susceptibilities and aid in the development and progression of dementia. Modified to each patient's genetic profile, precision medicine has the potential to detect groups at risk and make previously unheard-of predictions about the course of diseases. Precision medicine techniques have the potential to completely transform treatment and diagnosis methods. Targeted medications that target genetic abnormalities will probably appear, providing the possibility for more efficient and customized medical interventions. Investigating the relationship between genes and the environment may lead to preventive measures that would enable people to change their surroundings and minimize the risk of dementia, leading to the improved lifestyle of affected people. This paper provides a comprehensive overview of the genomic insights into dementia, emphasizing the pivotal role of precision medicine, and gene-environment interactions.

Cognitive reserve in the recovery and rehabilitation of stroke and traumatic brain injury: A systematic review

Objective: Cognitive reserve (CR) is the brain's ability to cope with changes related to aging and/or disease. Originally introduced to explain individual differences in the clinical manifestations of dementia, CR has recently emerged as a relevant construct in stroke and traumatic brain injury (TBI). This systematic review aims to investigate whether CR could predict post-stroke and TBI clinical recovery and rehabilitation outcomes, and how different variables used to estimate CR (i.e., proxies) are related to the prognosis and effectiveness of rehabilitation in these clinical populations. Method: A search was made in Pubmed, Embase, and PsycInfo for articles published until 12 January 2023, following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) protocol guidelines. Results: 31 studies were included after completing all screening stages. Overall, results show that a higher CR was associated with a better prognosis and a more effective rehabilitation in most of the clinical aspects considered: cognitive functioning, functional, occupational, and socio-emotional abilities, as well as psychiatric and neurological scales. Conclusions: A higher CR seems to be associated with a more favorable prognosis and a better rehabilitation outcome after stroke and TBI. Results suggest that CR should be taken into account in clinical practice to make more accurate predictions about recovery and effectiveness of rehabilitation. However, some inconsistencies suggest the need for further investigations, possibly using multiple proxies for CR.

Development and validation of the Upstream Social Interaction Risk Scale (U-SIRS-13): a scale to assess threats to social connectedness among older adults

Background

Social interactions are essential to social connectedness among older adults. While many scales have been developed to measure various aspects of social connectedness, most are narrow in scope, which may not be optimally encompassing, practical, or relevant for use with older adults across clinical and community settings. Efforts are needed to create more sensitive scales that can identify "upstream risk," which may facilitate timey referral and/or intervention.

Objective

The purposes of this study were to: (1) develop and validate a brief scale to measure threats to social connectedness among older adults in the context of their social interactions; and (2) offer practical scoring and implementation recommendations for utilization in research and practice contexts.

Methods

A sequential process was used to develop the initial instrument used in this study, which was then methodologically reduced to create a brief 13-item scale. Relevant, existing scales and measures were identified and compiled, which were then critically assessed by a combination of research and practice experts to optimize the pool of relevant items that assess threats to social connectedness while reducing potential redundancies. Then, a national sample of 4,082 older adults ages 60 years and older completed a web-based questionnaire containing the initial 36 items about social connection. Several data analysis methods were applied to assess the underlying dimensionality of the data and construct measures of different factors related to risk, including item response theory (IRT) modeling, clustering techniques, and structural equation modeling (SEM).

Results

IRT modeling reduced the initial 36 items to create the 13-item Upstream Social Interaction Risk Scale (U-SIRS-13) with strong model fit. The dimensionality assessment using different clustering algorithms supported a 2-factor solution to classify risk. The SEM predicting highest risk items fit exceptionally well (RMSEA = 0.048; CFI = 0.954). For the 13-item scale, theta scores generated from IRT were strongly correlated with the summed count of items binarily identifying risk (r = 0.896, p < 0.001), thus supporting the use of practical scoring techniques for research and practice (Cronbach's alpha = 0.80).

Conclusion

The U-SIRS-13 is a multidimensional scale with strong face, content, and construct validity. Findings support its practical utility to identify threats to social connectedness among older adults posed by limited physical opportunities for social interactions and lacking emotional fulfillment from social interactions.

Quality over quantity - rethinking social participation in dementia prevention: results from the AgeWell.de trial

BACKGROUND

Social participation as a protective factor against cognitive decline was one of the targets in the AgeWell.de study, a multi-domain interventional trial in a sample of older adults at increased risk for dementia. This study aimed to examine differential effects of the intervention and other influencing factors on social participation throughout the trial.

METHODS

A longitudinal analysis of study data at the primary follow-up after 24 months (n = 819) was conducted. The Lubben Social Network Scale (LSNS-6) was used to assess quantitative aspects of social networks, and self-reported social activities were classified using a three-tiered categorical framework to capture qualitative aspects.

RESULTS

A positive effect of the intervention was observed at the qualitative framework level, with an OR of 1.38 [95% CI: 1.05-1.82] for achieving or maintaining higher social participation at follow-up, while no effect could be detected on quantitative social network characteristics. Later phases of the Covid-19 pandemic showed a negative impact on the level of social participation at follow-up with an OR of 0.84 [95% CI: 0.75-0.95].

CONCLUSIONS

These findings suggest that by focusing on qualitative aspects of social participation as a component of dementia prevention, future interventions can promote enriched social interactions within established social networks.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS) ID DRKS00013555.

Korean Red Ginseng and Rb1 restore altered social interaction, gene expressions in the medial prefrontal cortex, and gut metabolites under post-weaning social isolation in mice

Background

Post-weaning social isolation (SI) reduces sociability, gene expressions including myelin genes in the medial prefrontal cortex (mPFC), and alters microbiome compositions in rodent models. Korean Red Ginseng (KRG) and its major ginsenoside Rb1 have been reported to affect myelin formation and gut metabolites. However, their effects under post-weaning SI have not been investigated. This study investigated the effects of KRG and Rb1 on sociability, gene expressions in the mPFC, and gut metabolites under post-weaning SI.

Methods

C57BL/6J mice were administered with water or KRG (150, 400 mg/kg) or Rb1 (0.1 mg/kg) under SI or regular environment (RE) for 2 weeks during the post-weaning period (P21-P35). After this period, mice underwent a sociability test, and then brains and ceca were collected for qPCR/immunohistochemistry and non-targeted metabolomics, respectively.

Results

SI reduced sociability compared to RE; however, KRG (400 mg/kg) and Rb1 significantly restored sociability under SI. In the mPFC, expressions of genes related to myelin, neurotransmitter, and oxidative stress were significantly reduced in mice under SI compared to RE conditions. Under SI, KRG and Rb1 recovered the altered expressions of several genes in the mPFC. In gut metabolomics, 313 metabolites were identified as significant among 3027 detected metabolites. Among the significantly changed metabolites in SI, some were recovered by KRG or Rb1, including metabolites related to stress axis, inflammation, and DNA damage.

Conclusion

Altered sociability, gene expression levels in the mPFC, and gut metabolites induced by two weeks of post-weaning SI were at least partially recovered by KRG and Rb1.

A More Connected Future: How Social Connection, Interdisciplinary Approaches, and New Technology Will Shape the Affective Science of Loneliness, a Commentary on the Special Issue

The recent Special Issue of Affective Science considered "The Future of Affective Science," offering new directions for the field. One recurring theme was the need to consider the social nature of emotional experiences. In this article, we take an interdisciplinary approach toward studies of social connection that builds upon current theoretical foundations to address an important public health issue - loneliness. Loneliness is an affective state that is characterized by feelings of isolation and has widespread adverse effects on mental and physical health. Recent studies have established links between loneliness, social connection, and well-being, but most of this work has been siloed in separate fields. We bridge these themes, leveraging advances in technology, such as artificial intelligence-based voice assistants (e.g., Alexa), to illuminate new avenues for detecting and intervening against loneliness "in the wild." Recognizing the power of connection among individuals as social beings and among researchers with shared goals, affective science can advance our understanding of loneliness and provide tangible benefits to society at large.

The link between social and emotional isolation and dementia in older black and white Brazilians

OBJECTIVE

To examine the link between social and emotional isolation and likelihood of dementia among older black and white Brazilians.

DESIGN

Cross-sectional clinical-pathological cohort study.

SETTING

Medical center in Sao Paulo, Brazil.

PARTICIPANTS

As part of the Pathology, Alzheimer's and Related Dementias Study, we conducted uniform structured interviews with knowledgeable informants (72% children) of 1,493 older (age > 65) Brazilian decedents.

MEASUREMENTS

The interview included measures of social isolation (number of family and friends in at least monthly contact with decedent), emotional isolation (short form of UCLA Loneliness Scale), and major depression plus the informant portion of the Clinical Dementia Rating Scale to diagnose dementia and its precursor, mild cognitive impairment (MCI).

RESULTS

Decedents had a median social network size of 8.0 (interquartile range = 9.0) and a median loneliness score of 0.0 (interquartile range = 1.0). On the Clinical Dementia Rating Scale, 947 persons had no cognitive impairment, 122 had MCI, and 424 had dementia. In a logistic regression model adjusted for age, education, sex, and race, both smaller network size (odds ratio [OR] = 0.975; 95% confidence interval [CI]: 0.962, 0.989) and higher loneliness (OR = 1.145; 95% CI: 1.060, 1.237) were associated with higher likelihood of dementia. These associations persisted after controlling for depression (present in 10.4%) and did not vary by race. After controlling for depression, neither network size nor loneliness was related to MCI.

CONCLUSION

Social and emotional isolation are associated with higher likelihood of dementia in older black and white Brazilians.

Validation and Cultural Adaptation of the Arabic Version of the Aging Voice Index

BACKGROUND

The aging voice index (AVI) is a 23-item self-administered, patient-reported outcome measure. It was developed in the English language to assess the impact of voice disorders on the elderly population.

OBJECTIVES

This study aimed to develop an Arabic version of the AVI (A-AVI), test its reliability and validity, and assess its psychometric aspects in Arabic-speaking elderly persons with voice disorders.

STUDY DESIGN/METHODS

This was an observational, cross-sectional study involving elderly patients aged ≥60 years. Eighty-two patients with voice disorders were included in the dysphonia group and 77 patients without voice disorders were included in the vocally healthy group. The translated A-AVI and Arabic voice handicap index 10 (A-VHI10) were distributed to the study groups. The A-AVI was tested for its reliability (test-retest reliability and internal consistency) and validity (content, construct, and concurrent with A-VHI10).

RESULTS

The A-AVI showed excellent test-retest reliability and internal consistency (intraclass correlation coefficient = 0.987 and Cronbach's alpha = 0.954, respectively). There was a significant difference in A-AVI scores between the elderly in the dysphonia and vocally healthy groups (P < 0.001). In addition, a significant correlation was demonstrated between A-AVI and A-VHI10 (r = 0.89). Unilateral vocal fold immobility and inflammatory laryngeal disorders were most frequently reported by the dysphonia group (28%).

CONCLUSIONS

A-AVI has excellent validity and reliability in Arab-speaking elderly patients with voice disorders. It can be considered in the assessment of the effect of voice disorders on the quality of life of the elderly.

Risk factors for the neurodegenerative dementias in the Western Pacific region

The Western Pacific Region (WPR) is characterized by a group of socioeconomically, culturally, and geopolitically heterogenous countries and represents a microcosm of the global endemic of neurodegeneration. This review will chart the known risk factors for dementia across the WPR. We explore the intersection between the established risk factors for dementia including the biomedical and lifestyle (cardiovascular and metabolic disease, sleep, hearing loss, depression, alcohol, smoking, traumatic brain injury, genetics) and social determinants (social disadvantage, limited education, systemic racism) as well as incorporate neuroimaging data, where available, to predict disease progression in the WPR. In doing so, we highlight core risk factors for dementia in the WPR, as well as geographical epicentres at heightened risk for dementia, to orient future research towards addressing these disparities.

Predictors of dementia among the oldest old: longitudinal findings from the representative "survey on quality of life and subjective well-being of the very old in North Rhine-Westphalia (NRW80+)"

BACKGROUND/AIMS

Our current study aimed to investigate the determinants of dementia among the oldest old using longitudinal data from a representative sample covering both community-dwelling and institutionalized individuals.

METHODS/DESIGN

Longitudinal representative data were taken from the "Survey on quality of life and subjective well-being of the very old in North Rhine-Westphalia (NRW80+)" that surveyed community-dwelling and institutionalized individuals aged 80 years and above (n = 1,296 observations in the analytic sample), living in North Rhine-Westphalia (most populous state of Germany). The established DemTect was used to measure cognitive impairment (i.e., probable dementia). A logistic random effects model was used to examine the determinants of probable dementia.

RESULTS

The mean age was 86.3 years (SD: 4.2 years). Multiple logistic regressions revealed that a higher likelihood of probable dementia was positively associated with lower education (e.g., low education compared to medium education: OR: 3.31 [95% CI: 1.10-9.98]), a smaller network size (OR: 0.87 [95% CI: 0.79-0.96]), lower health literacy (OR: 0.29 [95% CI: 0.14-0.60]), and higher functional impairment (OR: 13.45 [3.86-46.92]), whereas it was not significantly associated with sex, age, marital status, loneliness, and depressive symptoms in the total sample. Regressions stratified by sex were also reported.

DISCUSSION

Our study identified factors associated with dementia among the oldest old. This study extends current knowledge by using data from the oldest old; and by presenting findings based on longitudinal, representative data (also including individuals residing in institutionalized settings).

CONCLUSIONS

Efforts to increase, among other things, formal education, network size, and health literacy may be fruitful in postponing dementia, particularly among older women. Developing health literacy programs, for example, may be beneficial to reduce the burden associated with dementia.