Cognitive Function In Later Life Research Articles

Multigenerational Households During Childhood and Trajectories of Cognitive Functioning Among U.S. Older Adults.

ObjectivesFamily structure in childhood influences early brain development and cognitive performance in adulthood. Much less is known about its long-term impact on later-life cognitive functioning. We extend the two-generation family structure approach to investigate the potential contribution of living with grandparents in multigenerational households to differences in cognitive functioning at older ages.MethodsData were drawn from 9 waves of the Health and Retirement Study (1998–2014) merged with newly collected childhood family history data. Five types of family structure were assessed: two-parent households, two-parent households with grandparents, single-parent households, single-parent households with grandparents, and grandparent-headed households. Growth curve models were used to estimate trajectories of cognitive functioning over time.ResultsChildhood family structure was significantly associated with level of cognitive functioning, but not to rate of cognitive decline. Relative to those from two-parent households, individuals who grew up in multigenerational households showed higher levels of cognitive functioning, including those living with a single parent and grandparents. Those who lived with a single parent alone were the most disadvantaged. The effects of these multigenerational households persisted net of childhood and adulthood socioeconomic status and health outcomes.DiscussionGrandparent coresidence may cultivate a socially enriched home environment, providing resources and protection for early cognitive development that could persist throughout life. Multigenerational living arrangements are likely to increase as the contemporary population ages. More research needs to be done to understand the impact of these living arrangements on future generations’ brain health and cognitive aging.

Does Education Moderate the Relationship between Social Capital and Cognitive Function among Older Adults? Evidence from Suzhou City, China.

While social capital is recognized as an important protective determinant of cognitive function in later life, there is a lack of research examining the potential moderators and mediators in the mechanisms linking social capital to cognitive function. This study investigated the moderating role of education on the relationship between social capital and cognitive function among older adults in urban Chinese communities. Data were derived from a community survey conducted in Suzhou, Jiangsu Province, China, in late 2015. A quota sampling method was applied to recruit respondents aged 60 years or older from 16 communities in the Gusu district. The final analytic sample size was 446. Multiple group analysis was applied to test the proposed model. The results show that cognitive social capital was significantly associated with cognitive function in the high education group only. Structural social capital was not significantly associated with cognitive function. The findings highlight the important role of social capital in influencing cognitive function in later life. Social capital interventions could be particularly useful as a preventive approach to help older adults sustain their cognitive function levels. Policy and intervention implications are discussed.

Role of cumulative biological risk in mediating socioeconomic disparities in cognitive function in the elderly: a mediation analysis

ObjectivesTo evaluate whether allostatic load (AL), a measure of cumulative biological risk, fully or partially mediates observed socioeconomic status (SES) differences in cognitive function in the elderly.DesignCross-sectional mediation analysis.SettingCommunity-dwelling US...

Adverse childhood experiences and domain-specific cognitive function in a population-based study of older adults in rural South Africa.

Research on early life adversity and later-life cognitive function is conflicting, with little evidence from low-income settings. We investigated associations between adverse childhood experiences and cognitive function in an older population who grew up under racial segregation during South African apartheid. Data were from 1,871 adults aged 40-79 in the population-representative "Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" in 2015. The adverse childhood experiences were having a parent unemployed for > 6 months; having parents who argued or fought often; having a parent who drank excessively, used drugs, or had mental health problems; and physical abuse from parents. Executive function, language, visuospatial ability, and memory were assessed with the Oxford Cognitive Screen-Plus, a validated cognitive assessment designed for low-income, low-literacy settings. We estimated associations between adverse childhood experiences and latent cognitive domain z-scores using multiple-indicator, multiple-cause structural equation models. Childhood adversities were reported by 15% (parental unemployment for > 6 months), 25% (parents argued or fought often), 25% (a parent drank excessively, used drugs, or had mental health problems), and 35% (physical abuse from parent) of respondents. They were not associated with cognition, except that having a parent who drank excessively, used drugs, or had mental health problems was associated with lower memory z-scores (-0.07; 95% CI [-0.13, -0.01]). This is one of the first investigations into later-life cognitive outcomes associated with early adversity in a population with a historical context of pervasive trauma, and suggests that later-life memory may be vulnerable to early adversity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

A-013 The Impact of Anxiety and Depressive Disorders on Late-Life Cognitive Functioning

Abstract Objective Research indicates that the presence of psychiatric disorders is predictive of cognitive performance and increases the risk of developing dementia. Some have found that psychiatric disorders decrease cognitive performance while others have found that they increase cognitive performance. The purpose of the present study is to further investigate the relationship between psychiatric disorders and cognitive performance in older Veterans. Method The convenience sample included 216 older Veterans who were screened at the VA Palo Alto Health Care System (94% male, age = 71.8 ± 8.3). Psychiatric disorders (e.g., mood and anxiety disorders) were assessed using the Mini Neuropsychiatric Interview for DSM-IV. Domains of cognitive performance (e.g., Learning and Memory, Executive Function, Processing Speed, Attention, Visuospatial Ability, and Language) were measured using a comprehensive neuropsychological assessment battery. Results Results indicated that 25% of the sample had depression (n = 56) and 16% had anxiety (n = 34). Psychiatric diagnoses largely had no effect on executive function, processing speed, or language. Age was found to moderate the association between depression and learning and memory, though there were no main effects for depression on learning and memory. Anxiety was significantly associated with learning and memory performance, and age was found to further moderate that relationship. Age also moderated the association between depression and attention, though no main effects for depression were seen in the model. Anxiety had no effect on attention. Conclusions Age and psychiatric diagnoses interact to differentially impact cognitive functioning in late life. These findings support prior research on the complex relationship between psychiatric disorders and late-life cognitive impairment.

A-031 Early Childhood Quality of Education and Late-Life Cognitive Function in a Population-Based Sample from Puerto Rico

Abstract Objective Education quality may be related to disparities in late-life cognition in the U.S. We examined whether years of education and indicators of childhood quality of education (QOE) are associated with cognitive decline and cognitive impairment (CI) in older Puerto Ricans. Method Participants included 3,883 community-dwelling older adults aged 60+ years from the Puerto Rican Elderly: Health Conditions Study without CI at baseline. A composite of QOE included school year length, student-teacher ratio, attendance, and literacy levels for each municipality from Census and education reports (1926–1945). Cognitive functioning was measured by the minimental Cabán (MMC) at baseline and four-year follow-up. CI was assigned when MMC score was < 11 points. Covariate-adjusted logistic and linear regression models were used to examine incident CI and decline, respectively. Results Participants reported 8 years of education on average. Years of education (OR = 0.84; 95% CI = 0.79, 0.90; p = < .0001) was associated with a lower risk of incident CI but QOE was not (p = .37). In covariate-adjusted models, QOE (F(8, 2482) = 96.87, p < .05, R2 = .24) was significantly associated with cognitive decline. However, when years of education was added to the model, QOE was no longer statistically significant (p = .34). Conclusions This study provides further evidence that years of education and QOE are important factors for understanding risk of negative cognitive outcomes in older age, and that for this older Puerto Rican sample, years of education and literacy largely explained associations between QOE and late-life cognition.

Late-life cognition: Do childhood conditions play any role?

Individual's cognitive ability tends to reduce with ageing. Recently, whether and how to buffer this age-related decline is one of the greatest concerns. One well-established hypothesis argues that early life conditions play a particularly crucial role in developing individual's cognitive skills. People who grew up in good conditions are more likely to obtain a higher level of cognitive stocks and are more efficient producers of cognitive skills. In this paper, we analyze the impact of childhood conditions on the individuals' late life cognitive functioning by addressing the question whether the same change in age will have different consequences on the late life cognition given different levels of childhood conditions based on the China Health and Retirement Longitudinal Study (CHARLS) data. Our empirical evidence supports that more advantageous childhood conditions can shave off the decline of cognition as measured by word recall with ageing after controlling for individual fixed effects.

Sex Differences in Cognitive Health Among Older Adults in India.

To document sex differences in late-life cognitive function and identify their early-life determinants among older Indian adults. Harmonized Diagnostic Assessment of Dementia for Longitudinal Aging Study in India (LASI-DAD). Individual cognitive testing in hospital or household setting across 14 states of India. Individuals aged 60 years and older from LASI-DAD (2017-2019) (N = 2,704; 53.5% female). Given the low levels of literacy and numeracy among older Indian adults, we consider two composite cognitive scores as outcome variables. Score I is based on tests that do not require literacy or numeracy, whereas score II is based on tests that require such skills. Ordinary least squares is used to estimate models featuring a progressively increasing number of covariates. We add to the baseline specification, including a sex dummy, age, and state indicators, measures of early-life socioeconomic status (SES), early-life nutrition, as proxied by knee height, and education. Across most cognitive domains, women perform significantly worse than for men: -0.4 standard deviations (SD) for score I and -0.8 SD for score II. Early-life SES, health, and education explain 90% of the gap for score I and 55% for score II. Results are similar across hospital-based and home testing. In India, lower levels of early-life human capital investments in nutrition and education among women compared with men are associated with a female disadvantage in late-life cognitive health. This has important implications for public health policy, aiming at reducing the risk of cognitive decline and dementia-a nascent concern in India. J Am Geriatr Soc 68:S20-S28, 2020.

Education and Cognitive Functioning Across the Life Span

Cognitive abilities are important predictors of educational and occupational performance, socioeconomic attainment, health, and longevity. Declines in cognitive abilities are linked to impairments in older adults’ everyday functions, but people differ from one another in their rates of cognitive decline over the course of adulthood and old age. Hence, identifying factors that protect against compromised late-life cognition is of great societal interest. The number of years of formal education completed by individuals is positively correlated with their cognitive function throughout adulthood and predicts lower risk of dementia late in life. These observations have led to the propositions that prolonging education might (a) affect cognitive ability and (b) attenuate aging-associated declines in cognition. We evaluate these propositions by reviewing the literature on educational attainment and cognitive aging, including recent analyses of data harmonized across multiple longitudinal cohort studies and related meta-analyses. In line with the first proposition, the evidence indicates that educational attainment has positive effects on cognitive function. We also find evidence that cognitive abilities are associated with selection into longer durations of education and that there are common factors (e.g., parental socioeconomic resources) that affect both educational attainment and cognitive development. There is likely reciprocal interplay among these factors, and among cognitive abilities, during development. Education–cognitive ability associations are apparent across the entire adult life span and across the full range of education levels, including (to some degree) tertiary education. However, contrary to the second proposition, we find that associations between education and aging-associated cognitive declines are negligible and that a threshold model of dementia can account for the association between educational attainment and late-life dementia risk. We conclude that educational attainment exerts its influences on late-life cognitive function primarily by contributing to individual differences in cognitive skills that emerge in early adulthood but persist into older age. We also note that the widespread absence of educational influences on rates of cognitive decline puts constraints on theoretical notions of cognitive aging, such as the concepts of cognitive reserve and brain maintenance. Improving the conditions that shape development during the first decades of life carries great potential for improving cognitive ability in early adulthood and for reducing public-health burdens related to cognitive aging and dementia.

Childhood infectious diseases and old age cognitive functioning: a nationally representative sample of community-dwelling older adults

Cumulative evidence suggests that health-related risk factors during midlife and old-age are associated with cognitive impairment. However, studies are needed to clarify the association between early-life risk factors and impaired cognitive functioning to increment existing knowledge. To examine the association between childhood infectious diseases and late-life cognitive functioning in a nationally representative sample of older adults. Eligible respondents were 2994 community-dwelling individuals aged 65-85. Cognitive functioning was assessed using the Mini-Mental State Examination (MMSE). Childhood infectious diseases (i.e. chicken pox, measles, and mumps) were self-reported. The study covariates were age, sex, highest educational level achieved, smoking status, body mass index, and depression. The primary statistical analysis examined the association between the number of childhood infectious diseases and total MMSE scores, accounting for all study covariates. Regression models of progressive complexity were examined for parsimony. The robustness of the primary results was tested in 17 sensitivity analyses. The most parsimonious model was a linear adjusted model (Bayesian Information Criterion = 12646.09). Late-life cognitive functioning significantly improved as the number of childhood infectious diseases increased (β = 0.18; 95% CI = 0.11, 0.26; p < 0.001). This effect was not significantly attenuated in all sensitivity analyses. The current study results are consistent with prior ecological findings indicating that some childhood infectious diseases are associated with better cognitive functioning in old-age. This points to an early-life modifiable risk factor associated with older-life cognitive functioning. Our results may reflect selective mortality and/or beneficial effects via hormetic processes.

The Bidirectional Association Between Physical and Cognitive Function Among Chinese Older Adults: A Mediation Analysis.

This study investigated the bidirectional association between physical and cognitive function in later life and examined the mechanisms underlying the interrelationship. We employed cross-lagged panel models to analyze a sample of 4232 unique participants aged 65 years and older from three waves of the Chinese Longitudinal Healthy Longevity Survey. Physical activity and social participation were tested as potential mediators between physical and cognitive function. Our findings revealed a reciprocal relationship between physical and cognitive function and a reciprocal relationship between physical and cognitive decline. Moreover, physical activity was confirmed to mediate the bidirectional association between physical and cognitive function, whereas social participation did not seem to be a mediator. A vicious cycle linking physical and cognitive decline may exist in Chinese older adults. However, leading a physically active lifestyle could be an effective intervention to slow physical and cognitive aging, thereby toning down the vicious cycle.

Long-Term Intake of Dietary Carotenoids Is Positively Associated with Late-Life Subjective Cognitive Function in a Prospective Study in US Women

A protective association of dietary carotenoids with cognitive function has been suggested, but most studies have been relatively small with limited periods of follow-up. We examined prospectively long-term intakes of carotenoids in relation to subjective cognitive function (SCF), a self-reported, validated indicator of cognitive dysfunction. Among 49,493 female registered nurses with a mean age of 48 y in 1984, we used multinomial logistic regression to estimate the ORs and 95% CIs relating intakes of carotenoids to self-reported SCF in 2012 and 2014. Mean intakes of carotenoids were calculated from 7 repeated FFQs collected in 1984, 1986, and every 4 y afterwards until 2006. Self-reported SCF was assessed by a 7-item questionnaire on changes in memory and cognition; validity was supported by strong associations with Apolipoprotein E (APOE) ε4 genotype and concurrent cognitive function and cognitive decline measured by telephone-based neuropsychological tests. The mean values of scores assessed in 2012 and 2014 were categorized as "good" (0 points, 40.8%), "moderate" (0.5-2.5 points, 46.9%), and "poor" (3-7 points, 12.3%). Higher intake of total carotenoids was associated with substantially lower odds of moderate or poor cognitive function after controlling for other dietary and nondietary risk factors and total energy intake. Comparing the top with the bottom quintile of total carotenoids, the multivariable ORs were 0.86 (95% CI: 0.80, 0.93; P-trend<0.001) for moderate SCF and 0.67 (95% CI: 0.60, 0.75; P-trend<0.001) for poor SCF. This lower OR was also seen for carotenoids consumed 28 y before SCF assessment. Similar associations were found for total β-carotene, dietary β-carotene, α-carotene, lycopene, lutein+zeaxanthin, and β-cryptoxanthin. The significant associations for β-cryptoxanthin, lycopene, and lutein+zeaxanthin persisted after mutual adjustment for each other. Our findings support a long-term beneficial role of carotenoid consumption on cognitive function in women.

Late contributions of repetitive head impacts and TBI to depression symptoms and cognition.

To test the hypothesis that repetitive head impacts (RHIs), like those from contact sport play and traumatic brain injury (TBI) have long-term neuropsychiatric and cognitive consequences, we compared middle-age and older adult participants who reported a history of RHI and/or TBI with those without this history on measures of depression and cognition. This cross-sectional study included 13,323 individuals (mean age, 61.95; 72.5% female) from the Brain Health Registry who completed online assessments, including the Ohio State University TBI Identification Method, the Geriatric Depression Scale (GDS-15), and the CogState Brief Battery and Lumos Labs NeuroCognitive Performance Tests. Inverse propensity-weighted linear regressions accounting for age, sex, race/ethnicity, and education tested the effects of RHI and TBI compared to a non-RHI/TBI group. A total of 725 participants reported RHI exposure (mostly contact sport play and abuse) and 7,277 reported TBI (n = 2,604 with loss of consciousness [LOC]). RHI (β, 1.24; 95% CI, 0.36-2.12), TBI without LOC (β, 0.43; 95% CI, 0.31-0.54), and TBI with LOC (β, 0.75; 95% CI, 0.59-0.91) corresponded to higher GDS-15 scores. While TBI with LOC had the most neuropsychological associations, TBI without LOC had a negative effect on CogState Identification (β, 0.004; 95% CI, 0.001-0.01) and CogState One Back Test (β, 0.004; 95% CI, 0.0002-0.01). RHI predicted worse CogState One Back Test scores (β, 0.02; 95% CI, -0.01 to 0.05). There were RHI × TBI interaction effects on several neuropsychological subtests, and participants who had a history of both RHI and TBI with LOC had the greatest depression symptoms and worse cognition. RHI and TBI independently contributed to worse mid- to later-life neuropsychiatric and cognitive functioning.

Early-life food deprivation and cognitive performance among older Europeans

BackgroundEarly-life adversity, including food deprivation, has been linked with late-life cognitive function. Our aim was to explore the association between the early experience of hunger (the age at which it was experienced and its duration) and cognitive performance and decline among older Europeans. MethodsOur sample comprised dementia-free individuals aged ≥65 years who participated in waves 3 and 4 of the Survey of Health, Ageing and Retirement in Europe (SHARE). Information on periods of hunger during the life course was gathered in wave 3 (2009; SHARELIFE). Cognitive performance was assessed using tests of memory, verbal fluency and numeracy in waves 4 (2011) and 5 (2013). Regression models were used to assess the relationship between the experience of hunger at different ages and its duration and cognitive performance and decline while adjusting for age, sex, education, lifestyle and health factors. ResultsAmong a sample of 2131 individuals (mean age = 76.2 years; 50 % women), the experience of hunger when aged 0−4 years was associated with poorer immediate and delayed recall, fluency and impaired numeracy factors (B±SE=-0.58 ± 0.12; p < 0.001; B±SE=-0.74 ± 0.13; p < 0.001, B±SE=-1.60 ± 0.42; p < 0.001 and OR [95 % CI] = 0.57 [0.42−0.79], respectively). These results attenuated after controlling for duration of the experience of hunger but remained significant for immediate and delayed recall. The experience of hunger at ages 12−18 years was associated with better immediate recall, delayed recall and fluency (B±SE = 0.38 ± 0.15; p = 0.010; B±SE = 0.37 ± 0.17; p = 0.026, B±SE = 1.57 ± 0.53; p = 0.003, respectively). The associations of hunger with cognitive decline were similar but less robust. ConclusionsOur findings suggest that severe nutritional deprivation in early childhood may be associated with poor cognitive function in later life, while food deprivation in later childhood and adolescence may be protective.

Childhood Friendship Experiences and Cognitive Functioning in Later Life: The Mediating Roles of Adult Social Disconnectedness and Adult Loneliness

This study investigated the relationship between childhood friendships and cognitive functioning, as assessed with cognitive status and decline among adults aged 45 and older in China. We also examined the mediating effect of adult social disconnectedness and adult loneliness for this relationship. This study was based on 3 waves of data from the China Health and Retirement Longitudinal Study (CHARLS; 2011, 2013, 2015; N = 13,959). Cognitive functioning was assessed with episodic memory. Childhood friendship measures were taken from the 2014 life history module of the CHARLS. Two dimensions of adult social isolation, loneliness and social disconnectedness, were included as mediators. Latent growth curve modeling was utilized to test the associations between childhood friendships, adult social isolation, and cognitive functioning. Adverse childhood friendship experiences were found to be significantly associated with both lower initial cognitive status and the rate of decline in cognitive functioning. Our findings indicated that adult loneliness and social disconnectedness partly mediated the link between childhood friendship experiences and the initial level of cognitive functioning, but not cognitive decline later in life. The findings emphasized the enduring importance of childhood friendships for cognitive functioning later in life. Interventions that focus on improving social participation through fostering friendships in childhood may have long-term benefits for cognition later in life.

Sex differences in the relationship between dietary pattern adherence and cognitive function among older adults: findings from the NuAge study

BackgroundConsumption of a prudent dietary pattern rich in healthy nutrients is associated with enhanced cognitive performance in older adulthood, while a Western dietary pattern low in healthy nutrients is associated with poor age-related cognitive function. Sex differences exist in dietary intake among older adults; however, there is a paucity of research examining the relationship between sex-specific dietary patterns and cognitive function in later life.MethodsThe current study aimed to investigate sex differences in the relationship between sex-specific dietary pattern adherence and global cognitive function at baseline and over a 3-year follow-up in 1268 community-dwelling older adults (Mage = 74 years, n = 664 women, n = 612 men) from the Quebec Longitudinal Study on Nutrition and Successful Aging (NuAge). A 78-item Food Frequency Questionnaire was used to estimate dietary intake over the previous year. Sex-specific dietary pattern scores were derived using principal component analysis. Global cognition was assessed using the Modified Mini-Mental State Examination (3MS).ResultsAdjusted linear mixed effects models indicated that a healthy, prudent dietary pattern was not associated with baseline cognitive performance in men or women. No relationship was found between Western dietary pattern adherence and baseline cognitive function in women. Among men, adherence to an unhealthy, Western dietary pattern was associated with poorer baseline cognitive function (β = − 0.652, p = 0.02, 95% CI [− 1.22, − 0.65]). No association was found between prudent or Western dietary patterns and cognitive change over time in men or women.ConclusionsThese findings highlight the importance of conducting sex-based analyses in aging research and suggest that the relationship between dietary pattern adherence and cognitive function in late life may be sex-dependent.

Aging-Sensitive Networks Within the Human Structural Connectome Are Implicated in Late-Life Cognitive Declines

BackgroundAging-related cognitive decline is a primary risk factor for Alzheimer’s disease and related dementias. More precise identification of the neurobiological bases of cognitive decline in aging populations may provide critical insights into the precursors of late-life dementias. MethodsUsing structural and diffusion brain magnetic resonance imaging data from the UK Biobank (n = 8185; age range, 45–78 years), we examined aging of regional gray matter volumes (nodes) and white matter structural connectivity (edges) within 9 well-characterized networks of interest in the human brain connectome. In the independent Lothian Birth Cohort 1936 (n = 534; all 73 years of age), we tested whether aging-sensitive connectome elements are enriched for key domains of cognitive function before and after controlling for early-life cognitive ability. ResultsIn the UK Biobank, age differences in individual connectome elements corresponded closely with principal component loadings reflecting connectome-wide integrity (|rnodes| = .420; |redges| = .583), suggesting that connectome aging occurs on broad dimensions of variation in brain architecture. In the Lothian Birth Cohort 1936, composite indices of node integrity were predictive of all domains of cognitive function, whereas composite indices of edge integrity were associated specifically with processing speed. Elements within the central executive network were disproportionately predictive of late-life cognitive function relative to the network’s small size. Associations with processing speed and visuospatial ability remained after controlling for childhood cognitive ability. ConclusionsThese results implicate global dimensions of variation in the human structural connectome in aging-related cognitive decline. The central executive network may demarcate a constellation of elements that are centrally important to age-related cognitive impairments.

Development of a protective mental work demands questionnaire.

Research shows that mental demands at work affect later-life cognitive functioning and dementia risk, but systematic assessment of protective mental work demands (PMWDs) is still missing. The goal of this research was to develop a questionnaire to assess PMWDs. The instrument was developed in accordance with internationally recognized scientific standards comprising conceptualization, pretesting, and validation via confirmatory factor analysis (CFA), principal component analysis (PCA), and multiple regression analyses. We included 346 participants, 72.3% female, with an average age of 56.3 years. Item pool, sociodemographic questions, and cognitive tests: Trail-Making Test A/B, Word List Recall, Verbal Fluency Test, Benton Visual Retention Test, Reading Minds in the Eyes Test. CFAs of eight existing PMWD-concepts revealed weaker fit indices than PCA of the item pool that resulted in five concepts. We computed multivariate regression analyses with all 13 PMWD-concepts as predictors of cognitive functioning. After removing PMWD-concepts that predicted less than two cognitive test scores and excluding others due to overlapping items, the final questionnaire contained four PMWD-concepts: Mental Workload (three items, Cronbach's α = .58), Verbal Demands (four, Cronbach's α = .74), Information Load (six, Cronbach's α = .83), and Extended Job Control (six, Cronbach's α = .83). The PMWD-Questionnaire intends to assess protective mental demands at the workplace. Information processing demands and job control make up the primary components emphasizing their relevance regarding cognitive health in old age. Long-term follow-up studies will need to validate construct validity with respect to dementia risk.

Body mass index across adult life and cognitive function in the American elderly.

This study aimed to examine the associations of body mass index (BMI) across adult life with cognitive function in 2,637 participants aged 60 years or over from NHANES 2011-2014. The primary outcome was a composite score based on test scores on word list learning, animal naming, and digit symbol substitution. Exposures of interest included BMI at age 25, BMI 10 years before the survey, BMI at the survey (current BMI), and BMI burden calculated from age 25 to age at survey. BMI at age 25 was inversely associated with the composite score (β=-0.0271±0.0130 per kg/m2, P=0.038) and positively with low cognitive performance (odd ratio=1.04, 95% confidence interval: 1.01-1.07, P=0.010), defined as below 20 percentile of the composite score. Similar results were observed for BMI 10 years before the survey and BMI burden. Current BMI was positively associated with the composite score (β=0.0369±0.0113, P=0.001) and inversely associated with low cognitive performance (odd ratio=0.96, 95% confidence interval: 0.94-0.99, P=0.004). In conclusion, high BMI in early adult life is associated with low cognitive function in late life, which underscores the importance of a healthy body weight across the life course. The association between BMI and cognitive function at late life requires further investigation.

Social networks and cognitive function in older adults receiving home- and community-based aged care

ObjectivesSocial engagement has been linked to preserved cognitive functioning in later life. Yet, little is known about the specific network factors that best predict cognitive function in older adults. This study aimed to (i) characterize the quality and quantity of interpersonal relationships and (ii) explore the relationship between social network types and cognitive function in older adults receiving home- and community-based aged care services. MethodsParticipants (n = 175) receiving aged care services participated in a structured interview regarding their cognitive function (Telephone Interview for Cognitive Status-Modified), social networks (Lubben Social Network Scale-12) and quality of life (European Quality of Life Scale). Socio-demographic and aged care service use factors were obtained from provider electronic management systems. Multiple regression analyses were conducted to examine the relationships between the size and composition of clients’ social networks, aged care service use and cognition. ResultsThe sample had a median age of 81 years (range 61-96) and most were women (65.8%). Over a third (37.6%) had cognitive impairment and reported moderately high social networks. Males had higher social networks, were receiving fewer hours but more types of services, and had significantly better cognitive performance. Age, network size and composition were not associated with cognitive performance. DiscussionMore extensive social networks were associated with maintenance of cognitive health for older adults in community aged care. Whether this is causal or a marker of better cognitive health requires a longitudinal approach, and ideally should be tested with interventions at community levels.