Association of socioeconomic status and cognitive functioning change among elderly Chinese people

The dilution effect of healthy lifestyles on the risk of cognitive function attributed to socioeconomic status among Chinese older adults: A national wide prospective cohort study

Background

Lower socioeconomic status (SES) is a risk factor for poor cognitive function, while a healthy lifestyle is associated with better cognitive function. We examined the complex relationship between SES and a healthy lifestyle and cognitive function among older Chinese adults.

Methods

We used a national prospective cohort of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2008-18, aged 65 years and older with normal cognition at baseline. Participants were categorised into the favourable group if they had four to six healthy lifestyle factors and the unfavourable group for zero to three factors. SES was classified as higher and lower by assessing the socioeconomic vulnerability index (SEVI) with six components. Cognitive function was measured using the Mini-Mental State Examination (MMSE) scores and the standardised Z-scores. We applied the linear mixed effects and time-dependent Cox regression models to explore associations and further stratified the analysis by healthy lifestyles.

Results

A total of 6851 participants were included (the mean age was 80.87, 43.44% had a favourable lifestyle, and 49.29% had higher SES). Over the 10-year follow-up period, SES status and lifestyle profiles significantly affected the decline in the standardised Z-scores (P < 0.05). The higher SES group with favourable lifestyles exhibited a slower cognitive decline than those with lower SES (by 0.031 points per year, P < 0.05). The association was not observed in those in the unfavourable group (0.010 points per year, P > 0.05). During a follow-up, 25.06% of participants developed cognitive impairment (MMSE<18). We also observed a significant interaction between SES and healthy lifestyles (P < 0.05), with the corresponding associations of SES being more pronounced among participants with unfavourable lifestyles (hazard ratio (HR) = 0.821; 95% confidence interval (CI) = 0.701-0.960) than those with favourable lifestyles (HR = 1.006; 95% CI = 0.844-1.200).

Conclusions

A healthy lifestyle may attenuate the adverse impacts of lower SES on cognitive function among older adults. This study might provide important information for protecting cognitive function, especially in low- and middle-income countries.

Social support and cognitive activity and their associations with incident cognitive impairment in cognitively normal older adults

OBJECTIVES

To explore the associations of social support, and cognitive activity with cognitive impairment incidence, and further examine the mediation effect of cognitive activity on the association between social support and cognitive impairment incidence based on a nationwide elderly Chinese cohort.

METHODS

We collected the participants from an ongoing cohort of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 9394 older adults aged 65 or more years and free of cognitive impairment who participated in the CLHLS between 2008 and 2018 were included. The information on social support and cognitive activity was collected through a questionnaire. The incident cognitive impairment cases were identified through the Mini-Mental State Examination scale (MMSE). Cox proportional hazard regression models were conducted to calculate the hazard ratios (HRs) and 95% confidence interval (CI) of social support and cognitive activity associated with cognitive impairment. We used casual mediation models to assess the indirect association of cognitive activities underlying the association between social support and cognitive impairment.

RESULTS

The adjusted HRs (95% CI) of incident cognitive impairment were 0.956 (0.932 to 0.980), and 0.895 (0.859 to 0.933) associated with per 1 score increase in social support and cognitive activity score, respectively. Better adherence to social support was associated with a higher cognitive activity score (adjusted β = 0.046, 95% CI[0.032-0.060]). The baseline cognitive activity, as well as the mean cognitive activity at baseline and during the first follow-up wave, mediate the association between social support and the incidence of cognitive impairment, accounting for 11.4% and 12.6% of the total association, respectively. The participants who were aged 80 years or older, or those with mild daily functional limitations gained more benefits in the development of cognitive activity related to social support, leading to a reduction in the risks of cognitive impairment.

CONCLUSION

The results of this nationwide cohort provide consistent evidence linking social support, and cognitive activity to reduced risk of subsequent cognitive impairment incidence. These findings provide additional evidence to inform the social strategies to prevent cognitive impairment incidence in elderly people.

Subjective well-being patterns in older men and women without someone to confide in: a latent class analysis approach

Objective

This study aimed to identify the latent subtypes of subjective well-being (SWB) and associated factors in older adults without a confidant in China.

Methods

The data came from the most recent (seventh) wave (2018) of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). This cross-sectional study included 350 older adults who lacked a close confidant. We utilized latent class analysis and multiple logistic regression models to examine the latent SWB subtypes and associated factors.

Results

Three distinct patterns of SWB were identified: the very low SWB class (32%), the medium-low SWB class (46%), and the low evaluative and high affective SWB class (22%). The results indicated that compared to the low evaluative and high affective SWB class, respondents who self-rated their health as not good, currently drank alcohol and rated their financial status as poor/very poor were more likely to be in the very low SWB class, while those who participated in social activities were less likely to be in the very low SWB class. Respondents who had limitations in instrumental activity of daily living (IADL) and rated their financial status as poor/very poor were more likely to be in the medium-low SWB class. However, gender did not affect SWB patterns.

Conclusion

Our findings highlight awareness of the heterogeneity of SWB in older adults without close confidants and provide valuable information for the development of tailored intervention programs to improve their well-being.

Can the Frailty of Older Adults in China Change? Evidence from a Random-Intercept Latent Transition Profile Analysis

BACKGROUND

A major aspect of caring for older adults in the medical field is addressing their health risks. The term "frailty" is generally used to describe the changes in health risks of older adults. Although there is considerable heterogeneity in the Chinese older adult population who are classified as frail, there remain few relevant studies. Furthermore, there is a lack of research on the frailty status transitions of older Chinese adults at different time points. This research intends to determine the frailty status and category of older adults according to their physical, psychological, social, and cognitive function domains, and on this basis, to investigate changes in their frailty states.

METHODS

This article studied 2791 respondents who were over 60 years old (n = 2791; 53.2% were women) from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) follow-up survey on factors affecting the health of older adults in China. In this article, the frailty variables include self-reported health, social function, mental health, cognitive function, functional limitations, and morbidity status. Random-intercept latent transition profile analysis (RI-LTPA) was used to divide older adults into different subgroups, and then an in-depth analysis of the state transitions was conducted.

RESULTS

The latent profile analysis revealed that the evaluation results of the frailty state of older adults showed obvious group heterogeneity. Each fitting index supported four latent states, which were named according to the degree of the symptoms (i.e., multi-frailty, severe socially frailty, mild socially frailty, and relatively healthy frailty). Based on the categorical probability and the probability of transition, it can be concluded that most of the samples belonged to the healthy population, and the health status had generally improved across the four time points. The relatively healthy frailty group and the severe socially frailty group have relatively strong stabilities. The multi-frailty group and the mild socially frailty group had the highest probability of joining to the relatively healthy frailty group. Strengthening social interactions among older adults and promoting their participation in social activities can significantly improve their frail state.

CONCLUSIONS

This study supplements related research on frailty. Firstly, it deepens the meaning of frailty, which is defined based on four aspects: physical, psychological, cognitive, and social functioning. Secondly, it divides frailty into different sub-categories. Frailty is discussed from the perspective of longitudinal research, which can provide practical adjustment suggestions for older adult nursing intervention systems and measures in China.

The Role of Body Mass Index, Advanced Age, and Low Educational Attainment in Mild Cognitive Impairment among the Older Adult Population: A Study in a Rural Area in Indonesia

This study evaluated the prevalence of mild cognitive impairment (MCI) and factors associated with MCI among older adults in a rural area of Indonesia. This cross-sectional study was conducted in a rural area of East Java, Indonesia. Four hundred and twenty-seven older adults aged ≥60 years were included in the study. MCI was assessed using the Brain Health Test Cognitive Tool. Data related to possible risk factors were obtained using semi-structured questionnaires. The indirect body mass index was determined based on ulnar length. The prevalence of MCI was 12.9%. Being underweight (<18.5 kg/m2) (odds ratio [OR], 2.42; 95% confidence interval [CI], 1.17-4.97; p = 0.016), requiring assistance to manage money or medications (OR, 2.72; 95% CI, 1.02-7.23; p = 0.045), age ≥70 years (OR, 2.50; 95% CI, 1.11-5.60; p = 0.026), and having an educational attainment of ≤6 years (OR, 4.92; 95% CI, 1.92-12.60; p = 0.001) were significantly associated with MCI. In this Indonesian older adult population, underweight people who had an educational attainment of <6 years, those aged ≥70 years, and those who needed assistance to manage money or medications were more likely to have MCI.

Life Course Socioeconomic Position and Cognitive Aging Trajectories: A Cross-National Cohort Study in China and England

Background and Objectives

Cross-national research on cognitive aging inequality has largely concentrated on Western countries. It is unclear whether socioeconomic position (SEP) has similar effects on cognitive decline in emerging economies. We compared the association between life course SEP and cognitive function trajectories between China and England, the largest nation under state socialism and one of the oldest capitalist countries.

Research Design and Methods

This cross-cohort study examined participants aged 50 years and older from the China Health and Retirement Longitudinal Study (n = 12,832) and the English Longitudinal Study of aging (n = 8,875). Cognition z-scores were derived using comparable measures of memory and time orientation on 4 occasions. Life course SEP was self-reported by participants at baseline. Seven- to 8-year trajectories of cognition z-scores were estimated using latent growth curve modeling. Country- and gender-specific associations between childhood/adolescent deprivation, education, material wealth, and home ownership were evaluated in relation to model intercept (baseline level) and linear slope (annual rate of change) of cognition.

Results

After multivariable adjustment, education was positively associated with the greatest differences in baseline cognition across country and gender. Education was further linked to a slower rate of cognitive decline (z-score units per year); but compared with those with low education, Chinese men (b = 0.032) and women (b = 0.065) with high education had significantly slower declines than English men (b = -0.004) and women (b = 0.010) with high education.

Discussion and Implications

Despite substantial between-cohort differences in downstream and upstream determinants of dementia, education provided the greatest benefits to cognitive aging in England but particularly in China.

Low neighborhood deprivation buffers against hippocampal neurodegeneration, white matter hyperintensities, and poorer cognition

There is increasing recognition that socioeconomic inequalities contribute to disparities in brain and cognitive health in older adults. However, whether neighborhood socioeconomic status (SES) buffers individuals with low individual SES against neurodegeneration, cerebrovascular disease, and poorer cognitive function is not well understood. Here, we evaluated whether neighborhood deprivation (Townsend deprivation index) interacted with individual SES (composite household income and education levels) on hippocampus volume, regional cortical thickness, white matter hyperintensities, and cognition in 19,638 individuals (mean age = 54.8) from the UK Biobank. We found that individuals with low individual SES had the smallest hippocampal volumes, greatest white matter hyperintensity burden, and poorest cognition if they were living in high deprivation neighborhoods but that these deleterious effects on brain and cognitive function were attenuated if they were living in low deprivation neighborhoods (p for interactions < .05). While neighborhood deprivation did not interact with individual SES to influence regional cortical thickness, higher neighborhood deprivation was independently associated with lower cortical thickness in 16 regions (false discovery rate q < .05). Across multiple brain indices and cognitive function analyses, we found converging evidence suggesting that low neighborhood deprivation may have a neuroprotective effect against neurodegeneration, cerebrovascular pathology, and cognitive impairment, particularly in vulnerable individuals with low household income and education levels.

The path between socioeconomic inequality and cognitive function: A mediation analysis based on the HAALSI cohort in rural South Africa

Background

Socioeconomic position (SEP) strongly predicts late-life cognitive health, yet the pathways between SEP and cognitive function remain unclear. This study assessed whether and to what extent the association between SEP and cognitive function in the adult population in rural South Africa is mediated by some health conditions, behavioral factors, and social capital factors.

Methods

In this cross-sectional study, we used data from the 2014–15 “Health and Aging Africa: A Longitudinal Study of an INDEPTH Community in South Africa” (HAALSI) cohort, including 5,059 adults aged 40+ years from the Agincourt sub-district in Mpumalanga Province, South Africa. SEP, the independent variable, was measured based on ownership of household goods. Cognitive function, the dependent variable, was assessed using questions related to time orientation and immediate and delayed word recall. We used the multiple-mediation analysis on 4125 individuals with complete values on all variables to assess the mediating roles of health conditions (hypertension, diabetes, obesity, and disability), behavioral factors (leisure physical activity, alcohol consumption, and tobacco smoking), and social capital factors (community's willingness to help, trust, sense of safety, and social network contact) in the association between SEP and cognitive function.

Results

Compared to adults in the poorest wealth quintile, those in the richest wealth quintile had better cognition (β = 0.903, p &lt; 0.001). The mediation analysis revealed that health conditions mediated 20.7% of the total effect of SEP on cognitive function. In comparison, 3.3% was mediated by behavioral factors and only 0.7% by social capital factors. In the multiple-mediator model, 17.9% of the effect of SEP on cognitive function was jointly mediated by health conditions, behavioral factors, and social capital factors.

Conclusion

Low socioeconomic position is a significant factor associated with poor cognitive function among adults aged 40 years and above in South Africa. Health conditions mainly mediate the effects between SEP and cognitive function. Therefore, actions to prevent and control chronic health conditions can serve as the entry point for intervention to prevent poor cognitive function among people with low socioeconomic status.

Latent Classification Analysis of Leisure Activities and Their Impact on ADL, IADL and Cognitive Ability of Older Adults Based on CLHLS (2008-2018)

This study aimed to research the trajectory of leisure activity and the health status of older adults and analyze the effects of leisure activity on the health status of older adults. Based on the longitudinal data of CLHLS (2008-2018), the latent growth curve model (LGCM) was used; we found that the leisure activities (LA), activities of daily living (ADL) ability, instrumental activities of daily living (IADL) ability, and cognitive ability (COG) of older adults show a nonlinear downward trend over time. Furthermore, the panel binary regression analysis is used to find that leisure activities have significant inhibitory effects on ADL disorder, IADL disorder, and cognitive impairment in the older population. In addition, by using latent profile analysis (LPA), the older population is classified into three groups according to the homogeneity of the older adults' choice of leisure activities, namely the types of relaxation, entertainment, and intellectual-learning, respectively. Based on the classification results, the analysis of one-way ANOVA shows that the rates of ADL disorder, IADL disorder, and cognitive impairment of older adults with different types are significantly different. Moreover, the inhibitory effect of leisure activities on the rate of ADL disorder, IADL disorder, and cognitive impairment of older adults is more significant in the middle-aged and high-aged groups. Therefore, older adults should be encouraged to increase leisure activities, especially those who are middle-aged and high-aged.

Trends and disparities in sleep quality and duration in older adults in China from 2008 to 2018: A national observational study

Background

Poor sleep status as a common concern is a risk factor for many health problems among older people. China with an aging society lacks relevant nationwide data on the sleep status among older people. Therefore, the purpose of this study was to investigate trends and disparities in sleep quality and duration among older adults, and exploring influencing factors of poor sleep in China between 2008 and 2018.

Method

We used the four-waves data of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2008 to 2018. Sleep quality and average sleep hours per day was investigated by using questionnaires in the CLHLS. We categorized sleep duration as three groups including ≤5 h (short duration), 5-9 h (normal duration), or ≥9 h (long duration) per day. Multivariate logistic regression models were used to examine trends and risk factors of poor sleep quality, short sleep duration, and long sleep duration.

Results

The prevalence of poor sleep quality significantly increased from 34.87% in 2008 to 47.67% in 2018 (p < 0.05). Short sleep duration significantly increased from 5.29 to 8.37%, whereas long sleep duration decreased from 28.77 to 19.27%. Multivariate analysis showed that female sex, poor economic status, a greater number of chronic diseases, underweight, poor self-reported quality of life, and poor self-reported health were associated with poor sleep quality and short sleep duration (p < 0.05).

Conclusion

Our findings revealed that older adults had increased prevalence of poor sleep quality and short sleep duration from 2008 to 2018. More attention should be paid to the increased sleep problems among older adults and early interventions should be made to improve sleep quality and guarantee enough sleep time.

Health disparity and healthcare utilization inequity among older adults living in poverty in South Korea: a cross-sectional study

BACKGROUND

Korea has a two-tiered universal health security system: the wage-based National Health Insurance (NHI) program and government-subsidized Medical Aid (MA) program. Beneficiaries of the MA program belong to the lowest economic class. This study aims to investigate the association between economic status-defined as NHI or MA enrollment-and health disparity of older people aged ≥ 65 years in South Korea.

METHODS

The claims records of 672,525 older age population from the 2017 Health Insurance Review and Assessment Service-Adult Patient Sample were used to estimate adjusted odds ratios (aORs) of MA vs. NHI beneficiaries for prevalence for common geriatric diseases. Logistic regression and negative binomial regression were used to investigate the association between economic status and prevalence or healthcare utilization for each disease.

RESULTS

MA beneficiaries showed significantly higher prevalence than NHI beneficiaries for seven out of nine diseases (aORs ranging from 1.18 to 1.95). The discrepancy in the prevalence between the two groups was highest among those aged 65-69 years (aORs: 1.34-2.94), and diminished as they got older (aORs: 1.05-1.67). MA beneficiaries had significantly more outpatient visits to treat six diseases (aORs: 1.07-1.28), and more hospitalization to treat seven diseases (aORs:1.08-1.73) than NHI beneficiaries.

CONCLUSION

The higher prevalence of common geriatric diseases among MA than NHI beneficiaries confirms unfavorable health disparity in the elderly living in extreme poverty. Similar or higher healthcare utilization in treating the same conditions among MA beneficiaries suggests a low possibility of inequity for access to healthcare resources covered by the universal health security system due to poor economic status. Greater excess use of inpatient than outpatient care by MA beneficiaries implies that the condition of poor older adults might be more severe when diagnosed with the same disease.

Turning Point of Cognitive Decline for Chinese Older Adults from a Longitudinal Analysis: Protective Factors and Risk Factors

OBJECTIVES

To explore the turning point of cognitive decline in Chinese older adults and to explore the influencing factors including covariates.

PARTICIPANTS

Aged 65 and older whose cognitive function was normal at their first test.

METHODS

a secondary analysis that identified participants from the database of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Cohort-sequential design was used to categorize the data by age (rather than study wave), including the follow-up data of Chinese older adults aged 65-79 years and spanning 14 years. Cognitive function in 1278 participants was assessed using the Chinese Mini-Mental State Examination (CMMSE) in five waves over 14 years. Piecewise latent growth curve modeling was used to analyze the data.

RESULTS

(1) The turning point of cognitive decline in Chinese older adults occurs between the ages of 68 and 70. (2) There are statistically significant individual differences in the initial level of cognitive function and the growth rate of cognitive function before and after the transition stage. (3) Factors influencing cognitive function include residence, education level, smoking, drinking, exercise, leisure activities, social activities, Activities of Daily Living (ADL), and Instrumental Activities for Daily Living (IADL). (4) Exercise and ADL are the main protective factors, while smoking and drinking are the main risk factors.

CONCLUSIONS

There is a transition stage (68-70) in the decline of cognitive function in Chinese older adults and four main factors (such as smoking, drinking, exercise and ADL) have impacts on the cognitive decline. We should strengthen these protective factors (exercise and ADL) for the cognitive decline of older adults and avoid these risk factors (smoking, drinking). To prevent the decline of the cognitive function of older adults, the government should build more places conducive to activities for older adults and actively encourage older adults to improve their physical activity level. Given our findings, public health interventions centered on alcohol and tobacco cessation in older adults should be governmentally endorsed.

Joint developmental trajectories and temporal precedence of physical function decline and cognitive deterioration: A longitudinal population-based study

Objectives

Previous studies primarily explored the unidirectional impact of cognition on physical function. However, the interplay between physical function and cognition and the temporal precedence in their predictive relationships have not been elucidated. We explored the bidirectional mechanism between physical function and cognition in a longitudinal dataset.

Materials and methods

A total of 1,365 participants in the Chinese Longitudinal Healthy Longevity Survey assessed physical function and cognition in 2011 (T1), 2014 (T2), and 2018 (T3) by the Katz scale and the Chinese version of the Mini-Mental State Examination scale, respectively. Changes in the trajectories of physical function and cognition were examined using the latent growth model. The correlational and reciprocal relationships between physical function and cognition were examined using the parallel process latent growth model and autoregressive cross-lagged (ARCL) models.

Results

Cognition and physical function decreased by an average of 0.096 and 0.017 points per year, respectively. Higher physical function was associated with better cognition at baseline (r = 0.237, p &lt; 0.05), and longitudinal changes in physical function and cognition were positively correlated (r = 0.756, p &lt; 0.05). ARCL analysis indicated that physical function at T1 positively predicted T2 cognitive function. However, this predictive relationship reversed between T2 and T3, whereby cognitive function at T2 predicted physical function at T3.

Conclusion

Both physical function and cognition declined over time. Early identification and intervention in physical dysfunction among older adults could be critical to prevent further cognitive impairment and maintain functional independence. Hence, regular functional assessment and individualized care plans are required to achieve healthy aging.

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

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

The positive association between internal migration and hospitalization among the older adults in China: Regional heterogeneity and chronic disease management

Background

Post-retirement migrants are rapidly increasing in China, but the impact of internal migration on hospitalization among older adults remains under-researched. Understanding this impact is essential for health policies development and improvement. This study aims to identify the most vulnerable population, evaluate the association between migration and hospitalization, and discuss potential causes of the association.

Methods

14,478 older adults were extracted from the 2018 to 2019 Chinese Longitudinal Healthy Longevity Survey (CLHLS) database and divided into four groups according to migration experience and age at migration: non-migrants, pre-adulthood migrants, pre-retirement migrants, and post-retirement migrants. Post-retirement migrants were key research subjects. We employed Pearson's chi-square test to compare group differences in outcome and covariates, and multivariate logistic regression analysis to examine the association between migration and hospitalization by regions and chronic conditions.

Results

Significant intergroup differences were observed in demographic characteristics, socioeconomic factors, health habits, and health-related factors. Post-retirement migrants displayed following characteristics: female predominance (61.6%; 1,472/2,391), tending toward urban areas (80.9%; 1,935/2,391), and the highest prevalence rate of chronic disease (46.7%; 1,116/2,391). Urban migrants in eastern China were more likely to be hospitalized (OR = 1.65; 95% CI: 1.27-2.15), especially those who were diagnosed with chronic disease (OR = 1.51; 95% CI: 1.04-2.19) or with unconfirmed chronic conditions (OR = 1.98; 95% CI: 1.36-2.89).

Conclusions

Internal migration is associated with the hospitalization of post-retirement migrants moving to eastern China. Improved chronic disease management and early interventions might lower the hospitalization. Effective policies should be formulated to reduce the disparity in primary care services across China, thereby facilitating the access of migrants to these services.

Association of objective and subjective socioeconomic markers with cognitive impairment among older adults: cross-sectional evidence from a developing country

OBJECTIVE

This study explored how various markers of objective and subjective socioeconomic status (SES) are associated with cognitive impairment among older Indian adults.

DESIGN

A cross-sectional study was conducted using large nationally representative survey data.

SETTING AND PARTICIPANT

This study used data from the Longitudinal Ageing Study in India (2017-2018). The sample included 31 464 older adults aged 60 years and above.

PRIMARY AND SECONDARY OUTCOME MEASURES

Outcome variable was cognitive impairment, measured through broad domains of memory, orientation, arithmetic function, and visuo-spatial and constructive skills. We estimated descriptive statistics and presented cross-tabulations of the outcome. Χ2 test was used to evaluate the significance level of differences in cognitive impairment by subjective (ladder) and objective SES measures (monthly per-capita consumption expenditure (MPCE) quintile, education and caste status). Multivariable linear and logistic regression analyses were conducted to fulfil the objectives.

RESULTS

A proportion of 41.7% and 43.4% of older adults belonged to low subjective (ladder) and objective (MPCE) SES, respectively. Older adults with low subjective (adjusted OR (aOR): 2.04; p<0.05) and objective SES (aOR: 1.32; p<0.05) had higher odds of having cognitive impairment in comparison with their counterparts, with a stronger subjective SES-cognitive impairment association. Older adults with lower education or belonged to lower caste had higher odds of cognitive impairment than their counterparts. Interaction analyses revealed that older adults who belonged to lower subjective and objective (poorest MPCE quintile, Scheduled Castes and lowest education) SES had 2.45 (CI: 1.77 to 3.39), 4.56 (CI: 2.97 to 6.98) and 54.41 (CI: 7.61 to 388.93) higher odds of cognitive impairment than those from higher subjective and objective SES, respectively.

CONCLUSION

Subjective measures of SES were linked to cognitive outcomes, even more strongly than objective measures of SES; considering the relative ease of obtaining such measures, subjective SES measures are a promising target for future study on socioeconomic indicators of cognitive impairment.

Relationship between unmet needs for assistance and healthy aging among disabled older adults in China

Background

Although there is a growing consensus around the world that long-term care services and supports are important to help the aged population with disabilities achieve healthy aging, a misallocation of care resources and inefficiency in care delivery still exist in China. The absence or inadequate provision of long-term care services and supports among older adults with disabilities results in a range of adverse health consequences. However, the negative influence of unmet needs for assistance on healthy aging, based on functional perspectives including physiological, psychological, and societal domains, has been underestimated. This study aimed to measure healthy aging based on a person-centered approach and examine the relationship between unmet needs for assistance and healthy aging among older adults with disabilities in China.

Methods

Based on the data from the Chinese Longitudinal Healthy Longevity Survey 2018, we used the latent profile analysis with three indicators to uncover distinctive types of older adults experiencing distinct levels of healthy aging, and applied the ordered logit regression to analyze the correlation between unmet needs for assistance and different levels of healthy aging. To further address the endogeneity bias, the robust test was conducted by the two-stage least-squares instrumental variable estimation and the conditional mixed process instrumental variable estimation.

Results

Three ordered latent classes were identified: a low level of healthy aging (42.83%), a middle level of healthy aging (47.27%), and a high level of healthy aging (9.90%). Disabled older adults with unmet needs had a lower probability of achieving the higher level of healthy aging (OR = 0.57, SE = 0.04, CI = 0.48–0.66, p < 0.001).

Conclusions

This study highlights the need to increase awareness among gerontological practitioners with respect to long-term care services and supports for disabled older adults as a potential for enhancing their healthy aging, and that unmet needs could be a basis for risk assessment and a means for determining the efficacy of long-term care interventions on maintaining health.

Assessing socioeconomic inequalities in cognitive impairment among older adults: a study based on a cross-sectional survey in India

Background

The rapidly aging population is a major concern for countries, especially where cognitive health in older age is poor. The study examined the socioeconomic and health-related factors associated with cognitive impairment among older adults and the contribution of those factors to the concentration of low cognitive functioning among older adults from economically poor households.

Methods

Data this study were derived from the “Building Knowledge Base on Population Ageing in India” (BKPAI) survey, which was carried out in seven major states of India. The effective sample size for the analysis was 9176 older adults aged 60 years and above. Results from descriptive and bivariate analysis were reported in the initial stage. Multivariable logistic regression analysis was conducted to explore the associations. Additionally, the concentration index and concentration curve were used to measure socioeconomic inequality in cognitive impairment among older adults. Wagstaff decomposition was employed to explore the key contributors in the concentration index.

Results

Nearly 60% of older adults suffered from cognitive impairment in the study. The likelihood of cognitive impairment were higher among older adults with a low level of self-perceived income sufficiency [coefficient: 0.29; confidence interval (CI): 0.07- 0.52] compared to older adults with higher levels of perceived income status. Older adults with more than 10 years of schooling were less likely to be cognitively impaired [coefficient: -1.27; CI: − 1.50- -1.04] in comparison to those with no education. Cognitive impairment was concentrated among older adults from households with the lowest wealth quintile (concentration index (CCI): − 0.10: p < 0.05). Educational status explained 44.6% of socioeconomic inequality, followed by 31.8% by wealth status and 11.5% by psychological health. Apart from these factors, difficulty in instrumental activities of daily living (3.7%), caste (3.7%), and perceived income sufficiency to fulfil basic needs (3.0%) explained socioeconomic inequality in cognitive impairment among older adults.

Conclusions

Findings suggest that older adults with lower perceived income, lower levels of education, poor physical and mental health, and poor physical and social resources were more likely to be cognitively impaired. Education, wealth and psychological health are major contributors in socioeconomic inequality in late-life cognitive impairment, which may be target areas in future policy formulation to reduce the inequality in cognitive impairment in older Indian adults.

Effects of Leisure Activities on the Cognitive Ability of Older Adults: A Latent Variable Growth Model Analysis

Based on the data of four periods of CLHLS (2008, 2011, 2014, 2018), the latent variable growth model (LGCM) was applied to 2344 older adults who completed four follow-up surveys, to study the trajectory of leisure activities and cognitive ability and explore the relationship between leisure activities and cognitive ability of older adults. The results showed that: (1) leisure activities and cognitive ability of older adults showed a non-linear downward trend; (2) leisure activities significantly and positively predicted the cognitive ability of older adults at every time point; (3) the initial level of leisure activity positively predicted the initial level of cognitive ability but negatively predicted the rate of cognitive decline; In addition, cognitive activities had a greater effect on cognitive ability than non-exercise physical activities; (4) the rate of decline of leisure activities also significantly and positively predicted the rate of decline of cognitive ability; (5) cross-lagged regression analysis further suggested the overall positive predictive effect of leisure activity on cognitive ability; (6) overall, education level had a significant contribution to cognitive ability, and the higher the education level, the slower the decline of cognitive ability; and (7) smoking could promote cognitive ability in older adults and no significant effect was found between alcohol drinking and cognitive ability. Accordingly, the government should encourage older adults to do more leisure activities, especially the cognitive activity, to effectively prevent cognitive decline.

Rural/urban dwelling across the life-course and late-life cognitive ability in Mexico

BACKGROUND

Urban advantages in older adults' cognitive function have been observed. Less is known about early-life urban dwelling and late-life cognition. We evaluate how rural/urban dwelling throughout life and rural to urban shifts in life relate with cognition in Mexico, a country experiencing aging and urbanization.

METHODS

Data came from the 2003 and 2012 Mexican Health and Aging Study (n = 12,238 adults age 50+). Early-life urban dwelling was self-reported. Late-life urban dwelling was based on population size of respondents' community of residence (community 2500+ people) at the time of survey. Cognitive function was measured across several cognitive tasks. We assess differences in baseline cognitive function and nine-year decline across groups using a latent change score model.

RESULTS

Cross-sectionally, compared to always rural dwellers, rural-urban transitions were associated with cognitive benefits, though individuals residing in urban areas continuously through life exhibited the highest levels of cognitive function (β = 0.89, 95% CI: 0.83, 0.96) even after adjusting for SES, health, and health behaviors (β = 0.28, 95% CI: 0.22, 0.35). Longitudinally, always urban dwellers exhibited slower decline than always rural dwellers when adjusting for baseline cognition (β = 0.11, 95% CI: 0.03, 0.18), though faster decline when baseline cognition was not adjusted (β = -0.11, 95% CI: -0.18, -0.04). No differences were observed for cognitive change across comparison groups after adjusting for potential mechanisms.

CONCLUSIONS

Early- and late-life urban dwelling may result in cognitive advantages for older Mexican adults. Clinicians should consider where individuals resided throughout life to better understand a patient's likelihood of experiencing poor cognitive outcomes.

Examining the impact of socioeconomic status, demographic characteristics, lifestyle and other risk factors on adults' cognitive functioning in developing countries: an analysis of five selected WHO SAGE Wave 1 Countries

Background

Though extensive studies have been conducted on assessing the predictors of cognitive functioning among older adults in small community-based samples, very few studies have focused on understanding the impact of socioeconomic status (SES), demographic characteristics and other risk factors such as lifestyle and chronic diseases on the cognitive functioning among adults of all ages in a nationally representative population-based sample across low- and middle-income countries. This study, therefore, seeks to evaluate the impact of SES, demographic characteristics and risk factors on the cognitive functioning of adults across all ages in five selected developing countries.

Methods

Data from 12,430 observations obtained from the WHO Study on Global AGEing and Adult Health (SAGE) Wave 1; consisting of 2,486 observations each for China, Ghana, India, the Russian Federation, and South Africa, were used for the study. A meta-regression and a five-step hierarchical linear regression were used to analyze the data, with cognitive functioning as the dependent variable. Independent variables used in this study include SES; assessed by household income and education, demographic characteristics, other risk factors such as lifestyle, self-reported memory difficulty and chronic diseases.

Results

This study found that SES and lifestyle significantly predicted cognitive functioning in all the five selected countries as obtained by the pooled results of the meta-regression analysis. The hierarchical linear regression results also revealed that demographic characteristics such as age, type of residency, and self-reported memory difficulty significantly impact cognitive functioning in China, Ghana, Russia, and South Africa.

Conclusion

The findings in this study provide new insights for policymakers, caregivers, parents, and individuals, especially those in developing countries, to implement policies and actions targeted at improving SES and eliminating risk factors associated with cognitive decline, as these measures could help improve the cognitive functioning among their populations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12939-022-01622-7.

A Role of Socioeconomic Status in Cognitive Impairment Among Older Adults in Macau: A Decomposition Approach

Background

To explore the prevalence and inequality of cognitive impairment among older adults in Macau and the contributions of influencing factors to inequality in cognitive impairment.

Methods

The Montreal Cognitive Assessment (MoCA) was used to measure the prevalence of cognitive impairment. Socioeconomic status scores were used to describe economic level of the subjects. The concentration index was applied to measure the inequality of cognitive impairment associated with socioeconomic status (SES) and decomposed into its influencing factors.

Results

The prevalence of cognitive impairment was 44.35% in Macau. The concentration index of cognitive impairment among the elderly was −0.165 (95% CI: −0.232 to −0.098), indicating that the prevalence of cognitive impairment was concentrated in households with poor SES. Older age, poor SES, long or short sleep duration, other marital status, poor appetite, no tea/coffee drinking, no religious belief, and depression contributed positively to the inequality of cognitive impairment. Among these factors, SES made the largest contribution to inequality, accounting for 76.74%.

Conclusion

In Macau, the prevalence of cognitive impairment among people aged 65 years and older is concentrated among those who are in poor economic conditions. Reducing the gap between the rich and the poor at the source, increasing educational level of low SES population and improving their access to healthcare services will help to improve the inequity of cognitive impairment.

Longitudinal association between home and community-based services provision and cognitive function in Chinese older adults: Evidence from the Chinese Longitudinal Healthy Longevity Survey

Few studies have assessed the impact of home and community-based services (HCBSs) provision on cognitive function among older adults over time. This study examined the longitudinal association between HCBSs provision and cognitive function in Chinese older adults. The study included 5,134 participants aged 65 years and older in the Chinese Longitudinal Healthy Longevity Survey from 2008 to 2014. The Mini-Mental State Examination (MMSE) was used to evaluate cognitive function over the same time period. Participants were asked what kind of HCBSs were provided in his or her community. However, they were not asked whether services were utilised. The study used the number of HCBSs provided each wave to represent the strength of HCBSs, and used the MMSE score of each wave to represent the older adults' cognitive function status. A latent growth model was used to explore the relationship between HCBSs provision and cognitive function of older adults. The number of HCBSs provided was positively associated with older adults' cognitive function (2008: β = 0.03, p = 0.031; 2011: β = 0.06, p < 0.001; 2014: β = 0.06, p < 0.001) after controlling for gender, age, residence, education, income, medical insurance, activities of daily living disability, instrumental activities of daily living disability, serious illness, living arrangement and marital status. Results provided longitudinal evidence that an increase in HCBSs provision at a national level can result in better cognitive function in Chinese older adults.

Association of life course socioeconomic status and adult height with cognitive functioning of older adults in India and China

BACKGROUND

Cognitive functioning is an important measure of intrinsic capacity. In this study, we examine the association of life course socioeconomic status (SES) and height with cognitive functioning among older adults (50+) in India and China. The age pattern of cognitive functioning with measures of life course socioeconomic status has also been examined.

METHODS

Cross-sectional comparative analysis was conducted using the WHO's Study on global AGEing and adult health (SAGE) data for India and China. Multilevel mixed-effect linear regression analysis was used to examine the association of life course socioeconomic status and adult height with cognitive functioning.

RESULTS

In both India and China, parental education as a measure of childhood socioeconomic status was positively associated with cognitive functioning. The association between adult socioeconomic status and cognitive functioning was positive and significant. Height was significantly and positively associated with improved cognitive functioning of older adults in India and China. Furthermore, the age-related decline in cognitive functioning score was higher among older adults whose parents had no schooling, particularly in China. The cognitive functioning score with age was much lower among less-educated older adults than those with higher levels of education in China. Wealthier older adults in India had higher cognitive functioning in middle ages, however, wealth differences narrowed with age.

CONCLUSIONS

The results of this study suggest a significant association of lifetime socioeconomic status and cumulative net nutrition on later-life cognitive functioning in middle-income settings.

Nicotine smoking is associated with impaired cognitive performance in Pakistani young people

Nicotine smoking is the most common mode of tobacco smoking among young people. It affects the areas of the brain associated with memory, attention, and learning. This study has investigated the effect of nicotine smoking on cognitive performance. One hundred male volunteers (50 nicotine smokers and 50 nonsmokers) aged 18–30 years with similar socioeconomic backgrounds were recruited for this study. Clinical history of participants was obtained using a questionnaire. Their brain health and handedness were determined using the Mini Mental State Examination (MMSE) and the Edinburgh Handedness Inventory (EHI), respectively. The dependent variables examined in the study were attention-switching tasks (AST), pattern recognition memory (PRM), and choice reaction time (CRT). These parameters were assessed using the Cambridge Neuropsychological Automated Battery (CANTAB). The average ages of participating smokers and nonsmokers were 24.02 ± 3.41 years (mean ± standard deviation) and 22.68 ± 1.87 years, respectively. MMSE and EHI scores of smokers were 28.42 ± 1.09 and 99.75 ± 1.77, respectively; for nonsmokers, these scores were 28.54 ± 1.34 and 98 ± 1.91, respectively. The mean score for AST correct latency/delay was significantly higher (p = 0.050) in smokers (620.26 ± 142.03) than in nonsmokers (570.11 ± 108.39). The percentage of correct AST trials was significantly higher (p = 0.000) in nonsmokers (96.95 ± 2.18) than in smokers (83.75 ± 11.22). The PRM percent correct were significantly higher (p = 0.000) of nonsmokers (93.42 ± 8.34) than of smokers (79.75 ± 13.44). The mean correct latency for CRT was significantly higher (p = 0.009) in smokers (509.87 ± 129.83) than in nonsmokers (455.20 ± 65.73). From this data, it can be concluded that nicotine smoking is linked with impaired cognitive functions in smokers.

The impact of living arrangements and intergenerational support on the health status of older people in China: are rural residents disadvantaged compared to urban residents?

Research to-date has examined the impact of intergenerational support in terms of isolated types of support, or at one point in time, failing to provide strong evidence of the complex effect of support on older persons’ wellbeing. Using the Harmonised China Health and Retirement Longitudinal Study (2011, 2013 and 2015), this paper investigates the impact of older people's living arrangements and intergenerational support provision/receipt on their physical and psychological wellbeing, focusing on rural–urban differences. The results show that receiving economic support from one's adult children was a stronger predictor for higher life satisfaction among rural residents compared to urban residents, while grandchild care provision was an important determinant for poor life satisfaction only for urban residents. Having weekly in-person and distant contact with one's adult children reduced the risk of depression in both rural and urban residents. Older women were more likely than men to receive support and to have contact with adult children, but also to report poor functional status and depression. The paper shows that it is important to improve the level of public economic transfers and public social care towards vulnerable older people in rural areas, and more emphasis should be placed on improving the psychological wellbeing of urban older residents, such as with the early diagnosis of depression.

Tourism experiences and the lower risk of mortality in the Chinese elderly: a national cohort study

Background

Cohort studies about the effects of tourism experiences on the risk of death among Chinese older adults are still lacking. We aimed to examine the association between tourism experiences and mortality in Chinese aged 65 or above.

Methods

We included 9520 participants aged 65 years or above from the Chinese Longitudinal Healthy Longevity Survey at baseline in 23 provinces in 2011. They were followed up in 2014 and 2018. Cox proportional hazards models were used to assess the association between tourism experiences and the risk of death.

Results

Among 9520 participants, 7.85% had at least one tourism experience outside of their local city/county during the past 2 years. During 35,994.26 person-years of follow-up, in total 4635 deaths were observed. The crude rate of death was greater in participants who had no tourism experience than in older travelers (incidence rate: 13.70 versus 5.24 per 100 person-years). Elderly travelers had a significantly lower risk for all-cause mortality (crude hazard ratio: 0.38, 95% CI: 0.33–0.44) compared with non-travelers. After adjustment for all covariates, the risk of all-cause mortality was 27% lower among those with at least one tourism experience than among non-travelers (adjusted hazard ratio: 0.73, 95% CI: 0.62–0.85). Subgroup analysis showed that the associations between tourism and the decreased risk of mortality were stable.

Conclusions

Tourism decreases the risk of mortality in the Chinese elderly. Tourism should be considered as a modifiable lifestyle factor and an effective way to reduce mortality and promote longevity and healthy aging.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11099-8.

Association between socioeconomic status and cognitive functioning among older adults in Ghana

OBJECTIVES

Extensive analysis of the associations between socioeconomic status and cognition has been conducted among older adults. However, it is not clear whether associations in high-income countries are similar in low-and middle-income countries. This research aims to investigate the association between the socioeconomic status of older adults in Ghana and their cognitive function by using a sample of older adults that is nationally representative.

METHODS

Data were obtained from a sample of older Ghanaian adults (50+) from the Study of Global AGEing and Adult Health Wave 1 (n = 3710) of the World Health Organization. Objectively, cognition was measured by verbal recall, verbal fluency, forward digit span, and backward digit span, while variations in cognition overall were evaluated against socioeconomic factors using linear regression.

RESULTS

Older age, older women, rural life, increasing memory difficulty, and being diagnosed with stroke were the most significant determinants of impaired cognitive function. Higher education and higher income were significantly associated with a better cognitive function than those with no formal education and low income.

CONCLUSIONS

These results provide new evidence for public health programs in Ghana and other low-and middle-income countries to tackle cognitive impairments in growing populations.

Inequalities in cognitive impairment among older adults in China and the associated social determinants: a decomposition approach

Background

Despite there is growing evidence focusing on health inequalities in China, socioeconomic inequalities in cognitive impairment among older adults have received little attention. This study aims to measure socioeconomic inequalities in cognitive impairment among Chinese older adults, and determine the contributing social factors to the inequalities.

Methods

A cross-sectional analysis was performed using data from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 10,556 older adults aged 65 and over were included in the study. The prevalence of cognitive impairment was measured by using the Chinese version of the Mini-Mental State Examination. The socioeconomic inequalities in cognitive impairment were illustrated and quantified by the concentration curve and normalized concentration index. Multivariate logistic regression was conducted to identify the associated factors of cognitive impairment. And decomposition analysis was further applied to decompose the contribution of each determinant to the observed inequalities in cognitive impairment.

Results

The study indicated that the prevalence of cognitive impairment among Chinese older adults was 18.95%. The overall concentration index for cognitive impairment was − 0.046, which suggested a higher concentration of cognitive impairment among socioeconomically disadvantaged older adults. The results showed the prevalence of cognitive impairment was associated with sex, age, marital status, education level, occupation, economic status, emotional support, financial support, living arrangement, and participation in informal activities. Decomposition results further revealed the contributions of the determinants to the inequalities in cognitive impairment. Specifically, age (131.61%), marital status (85.68%), emotional support (84.85%), education level (39.73%), occupation (21.24%), sex (17.25%), financial support (− 4.19%), economic status (1.02%), living arrangement (0.88%), and informal activities (0.30%) have varying degrees of contributions to the inequality in cognitive impairment.

Conclusion

This study sheds light on the pro-rich inequality in cognitive impairment among older adults in China. It suggests that policymakers should pay more attention to older adults who are female, old-old, widowed, illiterate, economically disadvantaged, with no social support, and less socially involved. Also, more targeted interventions should be undertaken to improve the socioeconomic conditions of these vulnerable individuals and strengthen their ability to cope with the risk of cognitive impairment.

Prevalence and Patterns of Multimorbidity in a Nationally Representative Sample of Older Chinese: Results From the China Health and Retirement Longitudinal Study

BACKGROUND

Multimorbidity has become a prominent problem worldwide; however, few population-based studies have been conducted among older Chinese with multimorbidity. This study aimed to examine the prevalence of multimorbidity and explore its common patterns among a nationally representative sample of older Chinese.

METHODS

This study used data from the China Health and Retirement Longitudinal Study and included 19,841 participants aged at least 50 years. The prevalence of individual chronic diseases and multimorbidity during 2011-2015 were evaluated among the entire cohort and according to residential regions and gender. The relationships between participants' demographic characteristics and multimorbidity were examined using logistic regression model. Patterns of multimorbidity were explored using hierarchical cluster analysis and association rule mining.

RESULTS

Multimorbidity occurred in 42.4% of the participants. The prevalence of multimorbidity was higher among women (odds ratio [OR] = 1.31, 95% confidence interval [CI]: 1.13-1.51) and urban residents (OR = 1.14, 95% CI: 1.02-1.27) than their respective counterparts after accounting for potential confounders of age, education, smoking, and alcohol consumption. Hierarchical cluster analysis revealed four common multimorbidity patterns: the vascular-metabolic cluster, the stomach-arthritis cluster, the cognitive-emotional cluster, and the hepatorenal cluster. Regional differences were found in the distributions of stroke and memory-related disease. Most combinations of conditions and urban-rural difference in multimorbidity patterns from hierarchical cluster analysis were also observed in association rule mining.

CONCLUSION

The prevalence and patterns of multimorbidity vary by gender and residential regions among older Chinese. Women and urban residents are more vulnerable to multimorbidity. Future studies are needed to understand the mechanisms underlying the identified multimorbidity patterns and their policy and interventional implications.

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.

Socio-economic status and dementia onset among older Japanese: A 6-year prospective cohort study from the Japan Gerontological Evaluation Study

OBJECTIVES

Lower socio-economic status (SES) may be associated with dementia later in life, but there is inconsistent evidence supporting this claim. We aim to examine the association between three SESs (education, job, and income indicators) and dementia onset in older adults.

METHODS

Study design was a 6-year prospective cohort study. Participants included a total of 52 063 community-dwelling adults aged 65 years or older without long-term care needs from the Japan Gerontological Evaluation Study. Outcome variable was dementia onset. Explanatory variables were educational years, the longest job held, and equivalised household income. We performed Cox proportional hazard analysis by gender with multiple imputation.

RESULTS

During the follow-up period, 10.5% of participants acquired dementia. The adjusted risks of dementia incidence of the participants with less than 6 years of education were 1.34 times (95% confidence interval [CI], 1.04-1.73) in men and 1.21 (1.00-1.45) times in women higher than those with more than 13 years of education. Females with less than 1.99 million yen (hazard ratio = 0.83, 0.72-0.96) of equivalised income were less likely to acquire dementia than those with four million yen or higher.

CONCLUSIONS

Educational attainment had a robust impact on dementia onset compared with the other SES factors in both genders of older Japanese people. Securing an education for children could be crucial to prevent dementia later in life. The longest job held was less likely to be risks of dementia incidence, compared with the other two factors.

The association between family members' migration and cognitive function among people left behind in China

While internal migration is widely occurring in countries across the world and older people are more likely to be left behind by family members who out-migrated to other locations, little attention has been paid to the cognitive health of those people who have been left behind (PLB). Understanding how these demographic patterns relate to older persons' cognitive health may inform efforts to reduce the disease burden due to cognitive decline. Data came from the China Health and Nutrition Survey in 1997, 2000 and 2004. Participants aged 55 to 93 who participated in a cognitive function screening test (score range: 0-31) in two or more waves and provided information on family members' migration (n = 1,267) were included in the analysis. A mixed linear model was used to investigate the association between being left behind by any members who had not resided in the household for at least 6 months at baseline and cognitive function. Approximately 10% of the participants had been left behind by family members who migrated out of their communities. A significant interaction was observed in relation to cognitive function between being left behind and the number of years from the first test. Specifically, there was a less steep decline in cognitive function of PLB compared to people not left behind. This longitudinal study showed that PLB tended to have a higher cognitive function compared to those not left behind due to their relatively stable transition in cognitive function during the study period.

Education and Cognitive Aging: Accounting for Selection and Confounding in Linkage of Data From the Danish Registry and Survey of Health, Ageing and Retirement in Europe

Earlier studies report inconsistent associations between education and cognitive aging. We assessed the association, accounting for selective dropout due to death or dementia, and, in a subsample, accounting for confounding by early-life intelligence. Data from the Danish component of the Survey of Health, Ageing and Retirement in Europe (n = 3,400) were linked to registry data (education records, dementia diagnoses, and mortality) and the Danish Conscription Database (youth intelligence measurements for 854 men). Word recall and verbal fluency were assessed up to 4 times over 10 years (2004-2013) and combined by averaging the z scores. We fitted a joint model linking a time-to-event model for dementia or death to a linear mixed-effects model for cognitive change. Rate of cognitive decline was slower among people with high education compared with low education (β = 0.112, 95% confidence interval (CI): 0.056, 0.170). Adjusting for youth intelligence did not attenuate the association between education and cognitive decline (crude β = 0.136, 95% CI: 0.028, 0.244 vs. adjusted β = 0.145, 95% CI: 0.022, 0.269). The results suggest that higher education may slow cognitive decline in later life. In this sample, results changed little when accounting for selective attrition and confounding by intelligence.

Comprehensive Investigation of White Matter Tracts in Professional Chess Players and Relation to Expertise: Region of Interest and DMRI Connectometry

Purpose: Expertise is the product of training. Few studies have used functional connectivity or conventional diffusometric methods to identify neural underpinnings of chess expertise. Diffusometric variables of white matter might reflect these adaptive changes, along with changes in structural connectivity, which is a sensitive measure of microstructural changes.

Method: Diffusometric variables of 29 professional chess players and 29 age-sex matched controls were extracted for white matter regions based on John Hopkin's Mori white matter atlas and partially correlated against professional training time and level of chess proficiency. Diffusion MRI connectometry was implemented to identify changes in structural connectivity in professional players compared to novices.

Result: Compared to novices, higher planar anisotropy (CP) was observed in inferior longitudinal fasciculus (ILF), superior longitudinal fasciculus (SLF) and cingulate gyrus, in professional chess players, which correlated with higher RPM score in this group. Higher fractional anisotropy (FA) was observed in ILF, uncinate fasciculus (UF) and hippocampus and correlated with better scores in Raven's progressive matrices (RPM) score and longer duration of chess training in professional players. Consistently, radial diffusivity in bilateral IFOF, bilateral ILF and bilateral SLF was inversely correlated with level of training in professional players. DMRI connectometry analysis identified increased connectivity in bilateral UF, bilateral IFOF, bilateral cingulum, and corpus callosum in chess player's compared to controls.

Conclusion: Structural connectivity of major associational subcortical white matter fibers are increased in professional chess players. FA and CP of ILF, SLF and UF directly correlates with duration of professional training and RPM score, in professional chess players.