Associations of childhood socioeconomic status with mid-life and late-life cognition in Chinese middle-aged and older population based on a 5-year period cohort study

The U-shape Association between Population Agglomeration and Individual Depression: the Role of Dialect Diversity

Depression is a relevant mental illness affecting hundreds of millions of people worldwide. As urbanization accelerates, agglomeration of populations has altered individual social network distances and life crowding, which in turn affects depressive prevalence. However, the association between depression and population agglomeration (PA) remains controversial. This study aims to explore whether and how PA could influence individual depression. Based on the China Health and Retirement Longitudinal Study (CHARLS) 2018, the empirical results showed that there was a U-shaped association between PA and individual CES-D scores. As PA increases, the risk of depression first decreases and then increases. CES-D was lowest at moderate aggregation. Dialect diversity (DD) was positively related to the incidence of individual depression. The higher the DD, the higher the risk of depression. Meanwhile, DD also played a moderating role in the association between PA and individual depression. Our observations suggest that the optimistic level of agglomeration for individual mental health is within 1500 to 2000 persons per square kilometer.

Social frailty among older adults in India: Findings from the Longitudinal Ageing Study in India (LASI) - Wave 1

BACKGROUND

From an individual's perspective, social frailty may act as a key determinant of social capital, which is essential for meeting social needs and improvement of overall wellbeing. The present study aimed to understand the social frailty and its determining factors among Indian older adults.

METHODS

Data from the Longitudinal Ageing Study in India (LASI)-wave 1 was used. For the assessment of social frailty the study proposed a multidimensional Social Frailty Index (SFI) score ranging between 0 and 100 using 17 indicators. Bivariate analysis and quantile regression models were applied.

RESULTS

The study results indicated that on average female older adults (mean SFI = 63.7) are relatively more socially frail than male older adults (mean SFI = 59.0). Further, the quantile regression analysis revealed that at the 10th, 25th, 50th, and 75th percentiles, female older adults were significantly more likely to be socially frail than male older adults (β = 3.80, p < .01; β = 2.82, p < .01; β = 1.72, p < .01; and β = 2.62, p < .01, respectively). Educational attainment and better economic condition showed a protective effect against social frailty.

CONCLUSIONS

Investment to improve geriatric health status and socioeconomic conditions shall be a key focus to reduce social frailty prevalence among the older adults. A specific consideration is needed for addressing social frailty among female older adults.

Association of Childhood and Midlife Neighborhood Socioeconomic Position With Cognitive Decline

Importance

Early-life socioeconomic adversity may be associated with poor cognitive health over the life course.

Objective

To examine the association of childhood and midlife neighborhood socioeconomic position (nSEP) with cognitive decline.

Design, Setting, and Participants

This cohort study included 5711 men and women enrolled in the community-based Atherosclerosis Risk in Communities (ARIC) Study with repeated cognitive data measured over a median 27.0 years (IQR, 26.0-27.9 years) (1990-2019). Statistical analysis was performed from December 2022 through March 2023.

Exposure

Residence addresses for ARIC Study cohort participants were obtained at midlife (1990-1993) and as recalled addresses at 10 years of age (childhood). A composite nSEP z score was created as a sum of z scores for US Census-based measures of median household income; median value of owner-occupied housing units; percentage of households receiving interest, dividend, or net rental income; percentage of adults with a high school degree; percentage of adults with a college degree; and percentage of adults in professional, managerial, or executive occupations. Childhood nSEP and midlife nSEP were modeled as continuous measures and discretized into tertiles.

Main Outcomes and Measures

A factor score for global cognition was derived from a battery of cognitive tests administered at 5 in-person visits from baseline to 2019. The rate of cognitive decline from 50 to 90 years of age was calculated by fitting mixed-effects linear regression models with age as the time scale and adjusted for race, sex, birth decade, educational level, and presence of the apolipoprotein E ε4 allele.

Results

Among 5711 ARIC Study participants (mean [SD] baseline age, 55.1 [4.7] years; 3372 women [59.0%]; and 1313 Black participants [23.0%]), the median rate of cognitive decline was -0.33 SDs (IQR, -0.49 to -0.20 SDs) per decade. In adjusted analyses, each 1-SD-higher childhood nSEP score was associated with a slower (β, -9.2%; 95% CI, -12.1% to -6.4%) rate of cognitive decline relative to the sample median. A comparable association was observed when comparing the highest tertile with the lowest tertile of childhood nSEP (β, -17.7%; 95% CI, -24.1% to -11.3%). Midlife nSEP was not associated with the rate of cognitive decline.

Conclusions and Relevance

In this cohort study of contextual factors associated with cognitive decline, childhood nSEP was inversely associated with trajectories of cognitive function throughout adulthood.

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.

Direct and indirect associations between childhood socioeconomic status and cognitive function in the middle-aged and older adults in China

OBJECTIVES

To investigate whether childhood socioeconomic status (SES) is associated with cognitive function, and what factors might mediate the associations.

METHOD

Using data from the China Health and Retirement Longitudinal Study (CHARLS) and within frameworks of the latency model, the pathway model and the accumulation model, we quantified direct and indirect pathways between childhood SES and cognitive function for Chinese middle-aged and older adults aged 45+ by structural equations modeling.

RESULTS

We found significant direct, indirect and total effects of childhood SES on cognitive function at baseline. The indirect effects were mediated through educational attainment, household consumption, smoking behaviors and social engagement. At follow-ups, cognitive enhancement can be made by indirect pathways through educational attainment, improvement of household consumption and social engagement.

CONCLUSION

Our results supported the latency model, the pathway model and the accumulation model when considering pathways linking childhood SES to cognitive function. The findings underscored the value of taking early interventions to improve SES and cognitive function, especially among those with low childhood SES.

Childhood deprivations predict late-life cognitive impairment among older adults in India

Large population-based studies on the associations of childhood factors with late-life cognition are lacking in many low and middle income countries including India. In this study, we assessed the prevalence of late-life cognitive impairment and examined the associations of childhood socioeconomic status (SES) and health conditions with cognitive impairment among older adults in India. Data for this study were derived from the Longitudinal Ageing Study in India conducted in 2017–18. The effective sample size was 31,464 older adults aged 60 years and above. Cognitive functioning was measured through five global domains (memory, orientation, arithmetic function, executive function, and object naming). The overall score ranged between 0 and 43, and the score was reversed indicating cognitive impairment. Descriptive statistics along with mean scores of cognitive impairment were presented. Additionally, moderated multivariable linear regression models were employed to examine the association between explanatory variables, including childhood SES and health conditions and late-life cognitive impairment. The mean score of cognitive functioning among the study participants was 21.72 (CI 2.64–21.80). About 15% of older adults had poor health conditions, and 44% had lower financial status during their childhood. Older adults who had a fair health during their childhood were more likely to suffer from cognitive impairment in comparison to older adults who had good health during their childhood (Coef: 0.60; CI 0.39, 0.81). In comparison to older adults who had good childhood financial status, those who had poor childhood financial status were more likely to suffer from cognitive impairment (Coef: 0.81; CI 0.56, 1.07). Older adults who had fair childhood health status and poor childhood financial status were more likely to suffer from cognitive impairment in comparison to older adults who had good childhood health and good financial status (Coef: 1.26; CI 0.86, 1.66). Social policies such as improving educational and financial resources in disadvantaged communities and socioeconomically poor children and their families, would help to enhance a better cognitive ageing and a healthy and dignified life in old age.

The intersectionality of life course socioeconomic status, race, and cognitive decline: An 18-year follow-up

OBJECTIVES

Studies have documented the impact of childhood socioeconomic status (SES) on cognition. However, research that simultaneously considers SES in varied life stages, the multidimensional mechanisms, and racial differences is relatively understudied. This study examines the intersectionality across age, SES, and race and its impact on cognitive trajectories.

METHODS

Using 8376 respondents aged 65+ from the 1998-2016 Health and Retirement Study, we used latent growth curve modeling to examine the effects of four life course models (latency, pathway, accumulation, and mobility) on 18-year trajectories of mental status and episodic memory. We further tested for differences in the links between SES and cognitive trajectories between black and white respondents.

RESULTS

Cognitive function declines with age and is interrelated with SES and race. Adulthood has a stronger effect on cognitive performance than childhood. However, linked positive childhood and adulthood SES contributes to positive cognition. Accumulated SES disadvantages were associated with lower cognition. Older adults with downward mobility and low SES throughout their lifespans had the lowest cognition scores. Life course models operated differently on trajectories of cognitive decline, yet the effects were particularly evident among older black respondents. Overall, those with socioeconomic advantages tended to have a slower decline in cognition, while a faster decline occurred for those with accrued disadvantages.

CONCLUSIONS

Cognitive performance is a complex, longitudinal process intertwined with socioeconomic conditions and population heterogeneity shaped by life course contexts. Policies that facilitate healthy cognitive performance and address SES inequality could equalize health opportunities and address racial cognitive disparities later in life.

Earlier migration, better cognition? The role of urbanization in bridging the urban-rural cognition gaps in middle and older age

OBJECTIVES

With the process of population aging and urbanization, a vast amount of studies have confirmed the increasing urban-rural cognition gaps, while less is known about the extent to which cognition gaps can be explained by urban-rural difference and urbanization status. This study aimed to examine the role of urbanization in bridging the cognition gaps for Chinese middle-aged and older adults.

METHOD

Based on the national representative China Health and Retirement Longitudinal Study (CHARLS) 2015, the Blinder-Oaxaca decomposition method was employed. The method uses stratified linear regression to disaggregate cognition gaps into explained and unexplained differences, as well as the absolute and relative attribution of explanatory factors.

RESULTS

There were significant cognitive differences between urban and rural samples. Migrating to the urban predicts better cognition among the rural-born. A larger environment-related explained gap existed for those fully urbanized and those migrating earlier, indicating that migration can operate through a beneficial and cumulative change in the environment and bridge the urban-rural cognition gap.

CONCLUSION

Public health actions targeting cognitive disparities can benefit from focusing on the unequal distribution in urban-rural social and economic recourses. Areas of priority include promoting their socioeconomic status, physical functioning, social support, and lifestyles.

Cognitive reserve over life course and 7-year trajectories of cognitive decline: results from China health and retirement longitudinal study

Background

Cognitive reserve (CR) could partly explain the individual heterogeneity in cognitive decline. No study measured CR from a life course perspective and investigated the association between CR and trajectories of cognitive decline in older Chinese adults.

Methods

Data of 6795 Chinese adults aged 60+ from China Health and Retirement Longitudinal Study were used. Global cognition score (0–32) was assessed in all four waves. A life-course CR score was constructed using markers of childhood circumstance, education, highest occupational class, and leisure activities in later life. Latent growth curve modelling (LGCM) was applied to assess the association between CR and trajectories of cognitive decline.

Results

For the life-course CR, factor loadings of markers in adulthood and later life were larger than that of markers in childhood. The life-course CR score (ranged between − 2.727 and 6.537, SD: 1.74) was higher in urban Chinese adults (0.75, SD: 1.90) than in rural Chinese adults (− 0.50, SD: 1.43). The unconditional LGCM results showed that urban older Chinese adults had better global cognition at baseline (intercept: 15.010, 95% CI: 14.783, 15.237) and a slower rate of cognitive decline per year (linear slope: -0.394, 95% CI: − 0.508, − 0.281) than their rural counterparts (intercept: 12.144, 95% CI: 11.960, 12.329; linear slope: -0.498, 95% CI: − 0.588, − 0.408). After controlling for all covariates, one-unit higher CR score was associated with 1.615 (95% CI: 1.521, 1.709) and 1.768 (95% CI: 1.659, 1.876) unit higher global cognition at baseline for urban and rural older Chinese adults, respectively. The slower rate of cognitive decline associated with higher CR was more evident in rural residents (slope: 0.083, 95% CI: 0.057, 0.108) than in their urban counterparts (0.054, 95% CI: 0.031, 0.077).

Conclusions

CR was associated with better baseline cognition and slower cognitive decline in Chinese older adults. Although rural residents were disadvantaged in both CR and cognition, the protective effect of CR against cognitive decline was stronger for them than in those who live in urban area.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12671-6.

The long arm of childhood socioeconomic deprivation on mid- to later-life cognitive trajectories: A cross-cohort analysis

Introduction

Earlier studies of the effects of childhood socioeconomic status (SES) on later-life cognitive function consistently report a social gradient in later-life cognitive function. Evidence for their effects on cognitive decline is, however, less clear.

Methods

The sample consists of 5324 participants in the Whitehall II study, 8572 in the Health and Retirement Study (HRS), and 1413 in the Kame Project, who completed self-report questionnaires on their early life experiences and underwent repeated cognitive assessments. We characterized cognitive trajectories using latent class mixed models, and explored associations between childhood SES and latent class membership using logistic regressions.

Results

We identified distinct trajectories classes for all cognitive measures examined. Childhood socioeconomic deprivation was associated with an increased likelihood of being in a lower trajectory class.

Discussion

Our findings support the notions that cognitive aging is a heterogeneous process and early life circumstances may have lasting effects on cognition across the life-course.

Associations between childhood adversities and late-life cognitive function: Potential mechanisms

RATIONALE

Childhood adversity, which is related to negative cognitive consequences, is highly prevalent across the world. Nonetheless, there is still a scarcity of research on late-life cognitive function that accounted for multiple aspects of adverse events as well as the potential mediating mechanism of social context and individual's wellbeing in adulthood.

OBJECTIVE

This study aimed to investigate the relationship between childhood adversities and late-life cognitive function among the middle-aged and older Chinese population and to determine the mediating role of education attainment, marital status, financial status, and self-rated health in adulthood.

METHODS

We used three waves of data from China Health and Retirement Longitudinal Study from 2011 to 2015, which consisted of 23 807 participants aged 45 years and older. Generalized Estimating Equation and Structural Equation Model were applied to examine the association between childhood adversities and cognitive function (mental intactness and episodic memory) and the corresponding potential mechanisms.

RESULTS

Overall, 77.25%, 64.55%, 38.38%, and 15.03% of respondents experienced socioeconomic disadvantage, parental involved trauma, maladaptive parental trauma, and other trauma in childhood, respectively. Multivariate analyses suggest that all four types of childhood adversities were associated with a lower score of mental intactness and the first three were associated with episodic memory. A large proportion of the associations between childhood adversity and cognitive function was mainly mediated by education attainment, self-rated health and marital status in adulthood.

CONCLUSION

There are negative linkages between childhood adversities and cognitive function in the middle-aged and older Chinese population. Such associations were primarily functioning indirectly through adult social context and health conditions.

The influence of childhood adversities on mid to late cognitive function: From the perspective of life course

Background

The effects of childhood adversities on cognitive function in later life are well reported. However, few studies have examined the cumulative mechanism, especially in Chinese population. This study aims to explore this cumulative effects of childhood adversities on mid to late cognitive decline in China.

Methods

Data were drawn from the second and third wave of the China Health and Retirement Longitudinal Study (CHARLS). We included 9,942 respondents aged 45 and above and retrospectively collected information on childhood adversities. Cognitive function was measured in three dimensions: orientation and calculation, immediate memory, and delayed memory. A structural equation model was employed for analysis.

Results

Age (β = -0.155, P<0.001) and mid to late depressive symptoms (β = -0.041, P<0.001) showed direct effects on cognitive decline. Low mid to late life socioeconomic status (SES) showed a direct effect on mid-late cognitive impairment (β = 0.603, P<0.001) and an indirect effect through depression (β = 0.007, P<0.001). Low childhood SES (β = 0.310, P<0.001), lack of friends (β = 0.208, P<0.001), parental mental health problems (β = 0.008, P<0.001), and poor relationship with parents (β = 0.001, P<0.001) had an indirect effect on cognitive impairment.

Conclusions

Childhood adversities had negative effects on cognitive function among middle aged and elderly population in China. The findings suggest that early counter measures on childhood adversities may lead to an effective reduction of cognitive impairment.

Early life socioeconomic status predicts cognition regardless of education level

BACKGROUND AND PURPOSE

Early life socioeconomic status (SES) may impact cognitive performance later in life. We investigated the effect on cognitive performance of early life SES, education, and late life SES in the Brazilian Longitudinal Study of Adult Health.

METHODS

Path analysis was used to decompose associations between SES measures across the lifespan and cognition. The model included direct paths to cognition from early life SES, education, and late life SES, and indirect paths from early life passing through education and late life SES. We investigated whether the effects of early life SES are similar across middle-aged and older adults.

RESULTS

In 13,395 adults, the mean age was 51.5 (8.9) years, 54% were female, 53% were white, and 56% had at least college education. The direct path from early life SES remained significant in the presence of mediation paths through education, late life SES, or both, contributing to cognitive performance in both middle-aged and older adults. The indirect and total effect of early life SES was smaller for middle-aged compared to older adults. Early life SES continues to impact cognitive performance later in life independently of educational attainment and late life SES. The higher percent of mediation through education suggests that education may improve later life cognition even in the presence of low early life SES.

CONCLUSIONS

Our results highlight the importance of public health initiatives to improve early life SES and education to foster cognitive aging in low- and middle-income countries.

Relation of a Socioeconomic Index with Cognitive Function and Neuroimaging in Hypertensive Individuals

BACKGROUND

Socioeconomic factors are important contributors to brain health. However, data from developing countries (where social inequalities are the most prominent) are still scarce, particularly about hypertensive individuals.

OBJECTIVE

To evaluate the relationship between socioeconomic index, cognitive function, and cortical brain volume, as well as determine whether white matter hyperintensities are mediators of the association of the socioeconomic index with cognitive function in hypertensive individuals.

METHODS

We assessed 92 hypertensive participants (mean age = 58±8.6 years, 65.2%female). Cognitive evaluation and neuroimaging were performed and clinical and sociodemographic data were collected using questionnaires. A socioeconomic index was created using education, income, occupation (manual or non-manual work), and race. The associations of the socioeconomic index with cognitive performance and brain volume were investigated using linear regression models adjusted for age, sex, time of hypertension since diagnosis, and comorbidities. A causal mediation analysis was also conducted.

RESULTS

Better socioeconomic status was associated with better visuospatial ability, executive function, and global cognition. We found associations between a better socioeconomic index and a higher parietal lobe volume. White matter hyperintensities were also not mediators in the relationship between the socioeconomic index and cognitive performance.

CONCLUSION

Socioeconomic disadvantages are associated with worse cognitive performance and brain volume in individuals with hypertension.

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.

Association of self-perceived income sufficiency with cognitive impairment among older adults: a population-based study in India

BACKGROUND

Greater cognitive performance has been shown to be associated with better mental and physical health and lower mortality. The present study contributes to the existing literature on the linkages of self-perceived income sufficiency and cognitive impairment. Study also provides additional insights on other socioeconomic and health-related variables that are associated with cognitive impairment in older ages.

METHODS

Data for this study is derived from the 'Building Knowledge Base on Population Ageing in India'. The final sample size for the analysis after removing missing cases was 9176 older adults. Descriptive along with bivariate analyses were presented to show the plausible associations of cognitive impairment with potential risk factors using the chi-square test. Also, binary logistic regression analysis was performed to provide the relationship between cognitive impairment and risk factors. The software used was STATA 14.

RESULTS

About 43% of older adults reported that they had no source of income and 7.2% had income but not sufficient to fulfil their basic needs. Older adults with income but partially sufficient to fulfil their basic needs had 39% significantly higher likelihood to suffer from cognitive impairment than older adults who had sufficient income [OR: 1.39; OR: 1.21-1.59]. Likelihood of cognitive impairment was low among older adults with asset ownership than older adults with no asset ownership [OR: 0.83; CI: 0.72-0.95]. Again, older adults who work by compulsion (73.3%) or felt mental or physical stress due to work (57.6%) had highest percentage of cognitive impairment. Moreover, older adults with poor self-rated health, low instrumental activities of daily living, low activities of daily living, low subjective well-being and low psychological health were at increased risk for cognitive impairment.

CONCLUSION

The study highlights the pressing need for care and support and especially financial incentives in the old age to preserve cognitive health. Further, while planning geriatric health care for older adults in India, priority must be given to financially backward, with no asset ownership, with poor health status, older-older, widowed, and illiterate older individuals, as they are more vulnerable to cognitive impairment.

Impact of parental socioeconomic status on offspring's mental health: protocol for a longitudinal community-based study

INTRODUCTION

Socioeconomic status (SES) affects physical and mental health and cognitive functioning. The association between SES changes (SES mobility) and health has ethical and political implications in that the pernicious effects of inequality and the differential impact on social classes of economic and social policies. There is a lack of research conducted to explore the intergenerational transmission of parental SES changes on the offspring's mental health and cognitive functioning. We aim to fill this gap and identify roles of parental SES changes in offspring's mental health and cognitive outcomes.

METHODS AND ANALYSIS

This study will be based on a longitudinal cohort from the most populous municipality in the Canadian province of Quebec. Participants and their biological offspring will be invited to this study. For those with informed consent, we will collect their information on mental health, psychiatric disorders, cognitive functioning and early life experiences for offspring. Latent class growth analysis will be used to identify parental SES mobility groups. Multivariate regression analyses will be used to explore the roles of early life stress, parental SES mobility and their interactions in psychiatric disorders and cognitive functioning. Subgroup analyses (males and females) are also planned.

ETHICS AND DISSEMINATION

This study has been given ethical approval by the Research Ethics Board of the Douglas Mental Health University Institute (IUSMD-18/17). Each participant will provide informed consent on participation. We will disseminate research findings through publication in peer-reviewed academic journals and presentations at conferences. Lay summaries of major research findings will also be shared annually with our partners in the health system and community agencies located in the catchment area.

Early-Life Conditions and Cognitive Function in Middle-and Old-Aged Chinese Adults: A Longitudinal Study

A range of previous studies have suggested that early-life conditions (ELCs) are associated with various health problems throughout life in Western societies. The aim of this study was to investigate whether, and how, early-life conditions predicted the level and trajectory of cognitive function in middle- and old-aged Chinese adults. Data were obtained from China Health and Retirement Longitudinal Study which comprised 16,258 adults at baseline. Cognitive function was assessed using mental intactness and episodic memory and ELCs were measured by early parental death, childhood socioeconomic status (SES), food deprivation, and childhood health. Growth curve modeling was used to examine the trajectory of cognitive function (three waves in a 6-year period)with particular attention paid to the effects of ELCs on cognition. The results show that early maternal death is associated with the baseline cognitive level among middle- and old-aged Chinese adults (β range between −0.44 and −0.35, p < 0.05), but that this association is also largely attenuated by adulthood education. Higher childhood SES predicts an enhanced level of baseline cognition in both age groups (β range between 0.08 and 1.27, p < 0.001), but only protects against cognitive decline at baseline in middle-aged adults. Participants who were less healthy during childhood tended to have lower cognitive performance than those who had enjoyed good health (β range between −0.36 and −0.14, p < 0.05). The results of this study highlight the detrimental impact of deleterious ELCs on cognitive function throughout later life.

Associations of cardiovascular disease and depression with memory related disease: A Chinese national prospective cohort study

BACKGROUND

Association of cardiovascular disease (CVD) or depression and memory has been studied. But hardly any studies on the association of coexistence of CVD and depression and memory.

METHODS

This is a prospective cohort study of a nationally representative sample of 12,272 adults aged 45 years and more who participated in the China health and retirement longitudinal study 2011 to 2015. All variables were acquired by self-reporting questions. The associations between coexistence of CVD and depression with memory related disease (MRD) were investigated by using Cox proportional hazards regression models.

RESULTS

Among the 12,272 participants (mean age 65.69 years; 46.8% male) in this study, 56.9% no CVD or depression and 6.7% coexistence of CVD and depression. After adjustment for age, sex, marriage, living place, registered permanent residence, education level, smoking status, alcoholic intake, sleep status, nap status, social communication, health before 15 years, life satisfaction, cognitive function, and 11 chronic diseases risk factors, depression alone was significantly high risk for MRD (HR:1.64; 95% CI: 1.09-2.49); coexistence of CVD and depression increased the risk for MRD significantly higher (HR: 4.72; 95%CI: 2.91-7.64).

LIMITATIONS

Diseases were all self-reported and we couldn't adjust for all the potential confounders, which might be prone to information error and residual confounding.

CONCLUSIONS

In a nationally representative cohort with median 4 years of follow-up, depression alone and co-existence of depression and CVD could significantly increase the risk of MRD. Our study supports the idea of prevention of memory disease from a psycho-cardiology aspect.

Education and age-related decline in cognitive performance: Systematic review and meta-analysis of longitudinal cohort studies

Central theories of cognitive aging propose that education is an important protective factor for decline in cognitive performance in older age. We conducted a systematic review and meta-analysis of reported estimates of an association between educational attainment and change in performance in six cognitive domains (episodic memory, processing speed, verbal fluency, crystallized intelligence, fluid intelligence, and global ability) in the general population of older individuals. The systematic search (11^th of October 2019) identified 92 eligible articles. The episodic memory domain had the highest number of estimates (37 estimates from 18 articles, n = 109,281) included in the meta-analysis. The fewest estimates (6 estimates from 6 articles, n = 5263) were included for fluid intelligence. Pooled mean estimates from an inverse-variance weighted random effects analysis were not statistically significant and indicated that any association between education and change in cognitive performance is likely of a negligible magnitude. The estimates for education's role (one additional year) for change in cognitive performance ranged from -0.019 (95 % confidence interval, CI = -0.047, 0.010) to 0.004SD (CI = -0.003, 0.012) per decade. Even if the larger positive point estimates (i.e., protective effects) are selectively considered, the influence of education on change is still at least 12 times less important for the cognitive functioning of an older individual than the association between education and level of cognitive performance. Sensitivity analyses did not substantially alter these results. However, heterogeneity was substantial, and remained largely unexplained by mean age, mean educational attainment, Gini coefficient, GDP per capita, maximum follow-up period, and publication year. Overall, education is an important factor in aging due to its robust association with level of performance, but the current base of empirical evidence is not revealing a consistent and substantial association between educational attainment and changes in cognitive performance in the general population. Theories of cognitive aging must be updated to incorporate this pattern of findings.

Associations of cardiovascular disease and depression with memory related disease: A Chinese national prospective cohort study

BACKGROUND

Association of cardiovascular disease (CVD) or depression and memory has been studied. But hardly any studies on the association of coexistence of CVD and depression and memory.

METHODS

This is a prospective cohort study of a nationally representative sample of 12,272 adults aged 45 years and more who participated in the China health and retirement longitudinal study 2011 to 2015. All Variables were acquired by self-reporting questions. The associations between coexistence of CVD and depression with memory related disease (MRD) were investigated by using Cox proportional hazards regression models.

RESULTS

Among the 12,272 participants (mean age 65.69 years; 46.8% male) in this study, 56.9% no CVD or depression and 6.7% coexistence of CVD and depression. After adjustment for age, sex, marriage, living place, registered permanent residence, education level, smoking status, alcoholic intake, sleep status, nap status, social communication, health before 15 years, life satisfaction, cognitive function, and 11 chronic diseases risk factors, depression alone was significantly high risk for MRD (HR:1.64; 95% CI: 1.09-2.49); coexistence of CVD and depression increased the risk for MRD significantly higher (HR: 4.72; 95%CI: 2.91-7.64).

LIMITATIONS

Diseases were all self-reported and we couldn't adjust for all the potential confounders, which might be prone to information error and residual confounding.

CONCLUSIONS

In a nationally representative cohort with median 4 years of follow-up, depression alone and coexistence of depression and CVD could significantly increase the risk of MRD. Our study supports the idea of prevention of memory disease from a psycho-cardiology aspect.

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.

Early-life adversity and neurological disease: age-old questions and novel answers

Neurological illnesses, including cognitive impairment, memory decline and dementia, affect over 50 million people worldwide, imposing a substantial burden on individuals and society. These disorders arise from a combination of genetic, environmental and experiential factors, with the latter two factors having the greatest impact during sensitive periods in development. In this Review, we focus on the contribution of adverse early-life experiences to aberrant brain maturation, which might underlie vulnerability to cognitive brain disorders. Specifically, we draw on recent robust discoveries from diverse disciplines, encompassing human studies and experimental models. These discoveries suggest that early-life adversity, especially in the perinatal period, influences the maturation of brain circuits involved in cognition. Importantly, new findings suggest that fragmented and unpredictable environmental and parental signals comprise a novel potent type of adversity, which contributes to subsequent vulnerabilities to cognitive illnesses via mechanisms involving disordered maturation of brain 'wiring'.

Associations of childhood socioeconomic status with mid-life and late-life cognition in Chinese middle-aged and older population based on a 5-year period cohort study

OBJECTIVES

A prospective study was performed to examine the relationship of childhood socioeconomic status (SES) with cognition and the rate of change in a nationally representative sample of community-dwelling middle-aged and older Chinese population.

METHODS

This study mainly focused on 3 composite measures of cognitive function, including Telephone Interview of Cognitive Status, word recall, and drawing a figure successfully. Childhood SES was evaluated by parental occupation and education, childhood residence, and self-evaluated financial status. We designed an analysis strategy adding predictors incrementally in different models to examine the changes of effects of childhood SES on cognition by latent growth curve models.

RESULTS

Finally, a total of 10 533 respondents were prospectively studied, including 5980 respondents aged 45-59 and 4553 aged 60-90. Cognition in younger cohort showed a curvilinear change, while cognition in older cohort showed a linear decline. After controlling for covariates, middle-aged respondents with higher self-evaluated financial status (β: -0.22, P < .001), better health status (β: -0.13, P < .001), higher parental education (β: 0.17 and 0.10, P < .001), who had lived in city/town before 16 years (β: 0.69, P < .001), and whose fathers engaged in nonfarming work (β: 0.43, P < .001) were associated with the better baseline cognition. Similar results were found in older cohort. Additionally, early-life SES was not associated with cognitive decline in both cohorts.

CONCLUSIONS

This study indicates that childhood SES is associated with mid-life and late-life baseline cognition, but it is not contributed to cognition decline. Interventions in early-life focused on improving childhood SES might have positive impacts on baseline cognition in later-life.