Association between childhood parental literacy and late-life cognitive function: The Guangzhou Biobank Cohort Study

OBJECTIVES

Evidence on the associations of childhood parental education with late-life cognitive function remains inconsistent. Additionally, studies focusing on dimensions of cognitive function are scarce, with none from China. Therefore, we examined the associations of childhood parental education with late-life cognitive function and it's dimensions and investigated potential interactions.

STUDY DESIGN

A cross-sectional study.

METHODS

Participants were included from the third phase of Guangzhou Biobank Cohort Study. Mini-Mental State Examination (MMSE), Delayed 10-Word Recall Test (DWRT), and childhood parental literacy (could read or write) were collected. Multivariate linear and logistic regression were used.

RESULTS

Among 8891 participants aged ≥50 years, compared with those whose childhood parents could not read/write, those with only the father, only the mother, or both parents able to read/write during childhood had higher scores on the MMSE and its dimensions, and lower odds of mild cognitive impairment (MCI). The coefficients (β) and 95 % confidence intervals (CI) for scores of MMSE were 1.25 (1.10, 1.41), 1.36 (0.86, 1.86), and 2.05 (1.89, 2.21) respectively; the odds ratios and 95 % CIs for MCI were 0.38 (0.33, 0.45), 0.35 (0.18, 0.67), and 0.15 (0.12, 0.19) respectively. More pronounced effects were found in women, those aged ≥60, those with ≤ primary education, and in those whose childhood parents could read/write. Socioeconomic position mediated the association. Cognitive functions of attention and calculation in children of only fathers who could read/write (β = 0.43, 95%CI: 0.35, 0.50) and memory in children of only mothers who could read/write (β = 0.34, 95%CI: 0.16, 0.51) were associated with better outcomes. Consistent results were also found using scores from the DWRT.

CONCLUSIONS

Childhood parental literacy was associated with late-life cognitive function and it's dimensions, which mediated by socioeconomic position. Specifically, having only a father or only a mother who could read/write during childhood was associated with better cognitive function in attention/calculation and memory, respectively. These results add new evidence to support strategies for elderly cognitive health care.

Childhood and adult socioeconomic status influence on late-life healthy longevity: evidence from the Chinese longitudinal healthy longevity survey

Background

Older people in low- and middle-income countries are more susceptible to the impact of childhood experiences. This study comprehensively examines how childhood socioeconomic status (SES) and adult SES collectively influence late-life healthy longevity from a life course perspective, providing insights for shaping health-related policies.

Methods

This study analyzed data from the Chinese Longitudinal Healthy Longevity Survey (1998-2018) with 37,264 individuals aged 65 and above. Using R software, we applied continuous-time multi-state models incorporating the Rockwood frailty index with 38 indicators to assess participants' health. Childhood SES or life course SES trajectories were core explanatory variables, while age and gender were controlled. Multinomial regression estimated annual transition probabilities between different states, and the multi-state life table method calculated total and frailty-specific life expectancy (LE).

Results

(1) Social mobility among older people in China showed an upward trend from childhood to adulthood. (2) Transition probabilities for robust-frailty, robust-dead, and frailty-dead increased with age, while frailty-robust decreased. Transition probabilities and LE varied across different childhood SES (low, medium, high) or life-course SES trajectory categories (low-low, low-medium, low-high, medium-low, medium-medium, medium-high, high-low, high-medium, high-high), with probabilities of robust-frailty, robust-dead, and frailty-dead decreasing sequentially across different categories, and frailty-robust increasing sequentially across different categories. Total LE, robust LE, and robust LE proportion increased sequentially across different categories, while frailty LE decreased sequentially across different categories. (3) Women had higher total LE and frailty incidence, but lower recovery rate, mortality risk, robust LE, and robust LE proportion compared to men.

Conclusion

Favorable childhood SES and lifelong accumulation of SES advantages protect against frailty morbidity, improve recovery rate, reduce mortality risk, and increase total LE, robust LE, and robust LE proportion. High childhood SES has a stronger protective effect than high adult SES, indicating the lasting impact of childhood conditions on healthy longevity. Systematic interventions in education, food supply, and medical accessibility for children from impoverished families are crucial.

Intergenerational Educational Mobility and Cognitive Trajectories Among Middle-Aged and Older Chinese People: An Application of Growth Mixture and Mobility Contrast Models in Longitudinal Analysis

OBJECTIVES

Due to statistical challenges in disentangling the mobility effect (i.e., intergenerational educational mobility) from the position effect (i.e., parental and person's own education), the impact of intergenerational educational mobility on cognitive function remains unclear. We employed a novel approach to identify the mobility effect and investigate the net impact of intergenerational educational mobility on heterogeneous patterns of cognition among middle-aged and older adults in China.

METHODS

Participants aged 45 and older were recruited from the China Health and Retirement Longitudinal Study, a population-based prospective cohort study between 2011 and 2018. We identified cognitive trajectories using the growth mixture model (GMM) and subsequently employed the mobility contrast model (MCM) to examine the effects of intergenerational educational mobility on cognitive patterns stratified by gender.

RESULTS

Almost two thirds of respondents experienced intergenerational educational mobility, and 55% experienced upward mobility. Men had a higher rate of upward mobility than women. Three population-based cognitive patterns were identified: the low cognitive function with decline group (28%), the moderate cognitive function group (47%), and the high cognitive function group (26%). MCM analysis revealed that both upward and downward intergenerational educational mobility negatively affected cognitive trajectory patterns, extending beyond the influence of individuals' current and parental education.

DISCUSSION

In future research, the impact of mobility can be studied in longitudinal data sets by combining the GMM and MCM approaches. The net negative effect of intergenerational educational mobility on cognitive trajectory patterns indicates that it should be recognized as an independent predictor of cognitive decline.

The mediating effect of depressive symptoms on the association between childhood friendship and physical function in middle-aged and older adults: Evidence from the China Health and Retirement Longitudinal Study (CHARLS)

BACKGROUND

This study examines the extent to which depressive symptoms mediate the link between childhood friendship (CF) and physical function among middle-aged and older adults in China.

METHODS

China Health and Retirement Longitudinal Study (CHARLS) data were used; specifically, CHARLS life history survey (conducted from June 1-December 31, 2014) and follow-up health survey (conducted from July 1-September 30, 2015) data were used. The Sobel test, Bootstrap test and multivariable logistic regression were performed to examine the mediating role of depressive symptoms (measured by the 10-item Center for Epidemiologic Studies Depression Scale) in the association between CF (measured by a standardized retrospective questionnaire) and physical function, which was measured by basic activities of daily living (BADL) disability, instrumental activities of daily living (IADL) disability, and grip strength.

RESULTS

A total of 12,170 participants aged 45 years or older were included in this cross-sectional study. After controlling for covariates, low-quality CF was associated with an increased prevalence of BADL disability (OR = 1.18; 95 % CI = 1.05-1.32), IADL disability (OR = 1.25; 95 % CI = 1.12-1.40), and low grip strength (OR = 1.21; 95 % CI = 1.09-1.34). The proportion of the mediating effect of depressive symptoms was 48 % for CF and BADL, 40 % for CF and IADL, and 11 % for CF and grip strength. Depressive symptoms and worse CF have a joint effect on BADL disability (OR = 3.30; 95 % CI = 2.82-3.85), IADL disability (OR = 3.52; 95 % CI = 3.03-4.09), and low grip strength (OR = 1.65; 95 % CI = 1.43-1.92).

LIMITATIONS

Not all potential confounding factors (such as childhood behavioural problems, genetic factors, and memory function) were measured in the analysis, and there may have been recall bias in the retrospective collection of CF data.

CONCLUSIONS

Individuals with high-quality CF were more likely to have a decreased prevalence of impaired physical function in later life. Depressive symptoms acted as a mediator associated with the development of CF.

The long-term effects of childhood circumstances on older individuals: A systematic review

Childhood experiences are known to shape individuals' development and can influence various aspects of life later on. Understanding the long-term effects is crucial for informing interventions and policies aimed at promoting healthy aging. This review aimed to explore the long-term effects of childhood experiences on older individuals. This systematic review comprised three distinct phases. Firstly, a systematic review was conducted, exploring databases such as Google Scholar, PubMed, EMBASE, PsycINFO, and the Web of Science. Out of the 2116 studies initially identified, 24 studies were selected based on the inclusion criteria. Secondly, these inclusion criteria were applied to ensure that the chosen studies specifically delved into the connection between childhood experiences and outcomes in older individuals. Finally, data extraction and synthesis techniques were employed to analyze findings, facilitating the drawing of conclusions concerning the enduring impacts of childhood experiences on the well-being of older individuals. The review's findings revealed how negative experiences in childhood continue to affect older individuals in various ways. These early-life events have far-reaching consequences, profoundly impacting their physical health, making them more susceptible to chronic diseases and weakening their immune system. Additionally, they affect mental health, leading to conditions like depression, anxiety, and substance abuse. Cognitive function is also affected, resulting in memory problems and cognitive decline. Furthermore, these experiences impact social relationships, affecting trust, emotional control, and social isolation in later life. This review highlighted the enduring influence of childhood circumstances on the health and well-being of older individuals. Policymakers and health care practitioners should consider these findings when developing strategies to support healthy aging and mitigate the long-term effects of adverse childhood experiences.

Early life adversity, race, and childhood socioeconomic status: intersecting drivers of later life cognition

OBJECTIVES

Research on associations between early life adversity (ELA) and later life cognition has yielded mixed results and generally have not considered how broader societal systems of stratification potentially influence associations. The current study addresses this gap by exploring if racialized identity and childhood socioeconomic status (cSES) moderate associations between ELA exposure and later life cognition.

METHODS

Using data from the Health and Retirement Study (Waves 2010-2018), we used growth curve modeling to examine if the confluence of ELA, cSES, and racialized identity is associated with cognition.

RESULTS

Among White participants, greater exposure to ELA was associated with poorer baseline cognitive functioning, and higher cSES buffered against this association. Among Black participants, exposure to ELA was not associated with baseline cognitive functioning, regardless of cSES. We did not find evidence of any associations between main predictors nor their interactions with change in cognition over time.

CONCLUSIONS

This study provides evidence that associations between ELA and later life cognition is contingent upon multiple social positions in the United States. These findings support the importance of integrating insights on intersecting social positions within life-course-oriented efforts to reduce racialized cognitive disparities.

Does childhood parental death impact late life health directly and indirectly? Evidence from a National Survey in China

Despite growing interest in understanding the impact of childhood parental death, less is known about its long-term effects on older adults. We investigated the mediating role of poor health perception in the relationship between childhood parental loss and late life health. A cross-sectional study using data from the 2016 China Longitudinal Aging Social Survey was conducted. Our final sample featured 8,547 older adults. The prevalence of childhood parental death was 9.8%. Results indicated a significant direct impact of childhood parental death on depression and cognitive function. Mediating effects were observed, with older adults who experienced childhood parental loss perceiving their health status as significantly worse. This, in turn, predicted higher levels of objective physical impairment, greater depression, and lower levels of cognitive function. Our study offers the first empirical evidence of the enduring negative effects of childhood parental death as well as the pivotal mediating role of poor health perception.

Elder abuse and depressive symptoms among older adults in China: The moderating role of adverse childhood experiences

BACKGROUND

This study aimed to examine: (a) the associations between elder abuse and depressive symptoms among older adults in China, and (b) the moderating role of adverse childhood experiences (ACEs) on the relationships between elder abuse and its subtypes and depressive symptoms.

METHODS

This study used the cross-sectional data from the 2018 China Longitudinal Aging Social Survey (N = 8436, mean age = 71.3, 49.3 % female). Depressive symptoms were measured as CES-D scale. Elder abuse was evaluated by physical abuse, emotional abuse, and financial exploitation. ACEs were assessed via hunger, inadequate medical care, and death of parent(s) during childhood. Multiple linear regression models and interaction terms were used.

RESULTS

Elder abuse was significantly associated with increased depressive symptoms. Regarding elder abuse subtypes, when physical abuse, emotional abuse, and financial exploitation were included separately in regression models, they were all associated with increased depression. However, when all three subtypes were included simultaneously, only emotional abuse remained related to higher depression. Furthermore, ACEs acted as a moderator in the link between elder abuse and depressive symptoms. Specifically, moderate exposure to ACEs (exposure to one or two ACEs) attenuated the detrimental impacts of elder abuse on depression. For elder abuse subtypes, one and two ACEs alleviate the adverse effects of financial exploitation on depressive symptoms.

LIMITATIONS

Cross-sectional design is the major limitation.

CONCLUSIONS

The findings highlight the importance of considering the moderating role of ACEs when examining the association between elder abuse and depressive symptoms in later life.

Family instability in childhood affects language and memory in adulthood: results from the Pró-Saúde Study, Brazil

The study aims to investigate associations between adverse childhood psychosocial exposures and declarative memory, language, and executive function in adults with secondary schooling or more and without dementia. In 361 participants from the Pró-Saúde Study, we estimated associations between maternal educational attainment, principal source of the family´s income, food insecurity, and childhood family structure and performance in learning, word recall, and semantic and phonemic verbal fluency tests using multiple linear regression models. Individuals whose mother was the family breadwinner (mean difference: -1.97, 95%CI: -3.27; -0.72) and head-of-household (mean difference: -1.62, 95%CI: -2.89; -0.35) or who lived with a non-parental caregiver or in institutions in childhood (mean difference: -2.19, 95%CI: -4.29; -0.09) showed a reduction in the mean number of words in language and memory in adulthood. The results provide further evidence of the effect of adverse exposures in childhood. Without effective interventions, such exposures are likely to have far-reaching impacts on cognition.

The Role of Adverse Childhood Experiences in Multidimensional Nature of Subjective Age

OBJECTIVES

Age stereotypes and expectations about one's own aging commence in childhood, while most research focuses on predictive associations with midlife cognition and health outcomes in later life. This study instead aims to examine adverse childhood experiences (ACEs) contributing to multiple measures of subjective age (SA) among Chinese older adults and test whether these relationships differ by household registration (hukou).

METHODS

In a representative sample of Chinese older adults aged 60 and older from the 2018 China Longitudinal Aging and Social Survey (n = 7,815), ordinary least squares is used to examine the associations between ACEs and 3 facets of SA: felt age, look age, and self-defined aging standard.

RESULTS

Childhood starvation experience and limited health care access predict older felt age and look age, while parental death is associated with lower self-defined aging standard. Zooming in on hukou-specific associations shows that the dose-response relationship on older adults with rural hukou is particularly pronounced.

DISCUSSION

Findings provide empirical support for views of aging from a life-course perspective and highlight the enduring impact of ACEs for late-adulthood SA, as well as their differential influence on multiple indicators of SA. Interventions that focus on promoting health and development in childhood could potentially have effects beyond the childhood phase, and benefit for their positive aging attitude in later life.

Predictors of cognitive functioning trajectories among older Americans: A new investigation covering 20 years of age- and non-age-related cognitive change

Despite the extensive study of predictors of cognitive decline in older age, a key uncertainty is how much these predictors explain both the intercept and age- and non-age-related change in cognitive functioning (CF). We examined the contribution of a broad range of life course determinants to CF trajectories. Data came from 7,068 participants in the 1996-2016 Health and Retirement Study. CF was measured as a summary score on a 27-point cognitive battery of items. We estimated multilevel growth curve models to examine the CF trajectories in individuals ages 54-85. We found that the variation in CF level at age 54 was three times as much as the variation in age slope. All the observed individual predictors explained 38% of the variation in CF at age 54. Personal education was the most important predictor (25%), followed by race, household wealth and income, parental education, occupation, and depression. The contributions of activity limitations, chronic diseases, health behaviors (obesity, smoking, vigorous activity), childhood conditions (childhood health, nutrition, financial situation), gender, marital status, and religion were rather small (<5%). Even though the age slope varied with many adulthood factors, they only explained 5.6% of the between-person variation in age slope. Moreover, age explained 23% of within-person variation in CF from age 54 to 85. The rest non-age-related within-person variation could not be explained by the observed time-varying factors. These findings suggest that future research is urgently needed to discover the main determinants of the slope of cognitive decline to slow down the progression of cognitive impairment and dementia.

Leisure activities and cognitive impairment in old age: The role of life course socioeconomic status

In the current literature on cognitive function, life course socioeconomic status (SES) and engaging in leisure activities are often viewed as parallel measures of cognitive reserve that independently affect cognitive impairment in old age. Some studies also suggest that leisure activity mediates the effect of SES on cognitive impairment. What is less examined is the modification effect of SES on the association between engaging in leisure activities and cognitive impairment, especially from a life course perspective. In this study, we focus on the interaction effects of specific measures of SES and leisure activities on cognitive impairment. We use data from the Chinese Longitudinal Healthy Longevity Survey, which includes five waves of interviews with adults aged 65 and older between 2002 and 2014. Cognitive impairment is measured by the Chinese version of the Mini-Mental Status Examination. Childhood and adulthood SES and participation in seven leisure activities are included in this analysis. We adopt a lagged independent variable approach and the Generalized Linear Mixed Model to conduct the analysis. Findings confirm that higher SES in both childhood and adulthood are associated with low levels of cognitive impairment in the older Chinese population. Furthermore, there are significant interaction effects between specific life course SES and leisure activities with a consistent pattern: Those of higher life course SES enjoy extra benefits from engaging in leisure activities. The findings point to a modification mechanism that connects life course SES, leisure activities, and cognitive health inequality among older adults.

The Long-Term Effect of Famine Exposure on Cognitive Performance: Evidence from the 1959-1961 Chinese Famine

We examined the long-term impact of the 1959-1961 Chinese Famine on the survivors' cognitive performance in this study. Using data from the 2010 China Family Panel Study, our cohort comparison analysis showed that people who experienced the famine in early childhood (aged 1-3) had a lower score on a vocabulary test and that those who were exposed to the famine in utero did not differ from those born after the famine, probably due to positive selection for the in utero survivors. To deal with the problem of the lack of a comparable control group, we further applied a migrant-stayer comparison approach, with data from the 2016 China Family Panel Study and the 2017 Hong Kong Panel Study of Social Dynamics, to examine the effects of famine exposure at different life stages on adult cognition. We compared the people who stayed in Guangdong with the people who crossed the border to Hong Kong before the famine. The results showed that Guangdong stayers who experienced the famine when they were aged 1-18 had worse performance in immediate word recall. The findings suggested that exposure to malnutrition during childhood has long-term adverse effects on cognitive performance.

Childhood experiences and frailty trajectory among middle-aged and older adults in China

This study examined the associations between childhood experiences and frailty trajectory among middle-aged and older Chinese adults. Data were derived from the China Health and Retirement Longitudinal Study. We used data from all four waves (i.e., 2011, 2013, 2015, 2018) and the life history survey in 2014. Data for 10,963 respondents were included. Latent growth curve models were conducted to examine the proposed model. The results show that adverse childhood experiences, self-rated childhood socioeconomic status, and the objective indicators of childhood health and health care were associated with both the baseline level and change rate of frailty. The educational attainment of fathers and perceived childhood health and healthcare conditions were associated with baseline frailty only. Our findings highlight the crucial role of childhood antecedents in the progression of frailty in later life. We further found strong evidence that childhood is an essential life stage for human development. Future social policies and interventions should use childhood experiences as a screening tool and promote child protection, health education, and life course interventions.

Educational mobility and older adults' working memory updating ability: association and role of resilience

OBJECTIVE

Previous research revealed that a low childhood socioeconomic status, including low parental education, correlates with impaired executive functioning. However, there is a lack of research on the association of working memory updating (WMU) ability, which is one of the major components of executive functioning, and of resilience with educational mobility. The purpose of the present two studies was to further examine these associations.

METHOD

In Study 1, 180, 60-88-year old adults with different levels of educational mobility performed a WMU task. In Study 2, 130, 60-89-year old adults that had experienced different levels of upward educational mobility completed a WMU task and a resilience questionnaire.

RESULTS

Study 1 revealed that extent of educational mobility was significantly positively associated with WMU ability. Study 2 revealed significant positive associations among extent of educational mobility, resilience, and WMU task performance.

CONCLUSION

The results were discussed in terms of possible causal relations between the variables and implications for interventions that aim to enhance upward educational mobility and cognitive functioning in late adulthood.

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.

Associations between childhood maltreatment and educational, health and economic outcomes among middle-aged Chinese: The moderating role of relative poverty

BACKGROUND

Despite substantial evidence in developed countries showing that child maltreatment can lead to serious life-long consequences, relatively few studies so far have examined the associations between childhood maltreatment and adulthood outcomes in developing countries, such as China. It also remains unclear as to the impact of relative poverty on the long-term development of maltreated children.

OBJECTIVE

This study aims to investigate the associations between childhood maltreatment and educational, health, and economic outcomes among middle-aged Chinese, as well as explore the moderating effects of relative poverty.

PARTICIPANTS AND SETTING

The participants of this study were the middle-aged respondents (aged 45 to 59) in the 2011, 2013, and 2015 China Health and Retirement Longitudinal Studies (CHARLS) and the CHARLS Life History Survey (N = 24,114).

METHODS

Physical abuse and emotional neglect were measured to investigate childhood maltreatment. Subjective and objective indicators were used to examine relative poverty. A broad range of midlife outcomes were explored, including educational attainment, physical health, mental health, cognitive functions, labor force participation, wage expenditure, and financial strain. Data analyses were conducted using fixed effects model for panel data and a propensity score matching approach.

RESULTS

Childhood physical abuse and emotional neglect were both significantly associated with lower levels of midlife educational attainment, cognitive functions, individual wages, and household expenditures, as well as higher rates of chronic diseases, depressive symptoms, poverty, and welfare involvement. Childhood physical abuse also predicted higher risks of difficulty performing the activities of daily living (ADL), unemployment, and fewer work hours. Early-life exposure to relative poverty was linked to a greater likelihood of childhood maltreatment and mid-life adversities. It further aggravated the negative impacts of childhood maltreatment on middle-age outcomes.

CONCLUSION

Child maltreatment had a profound effect on long-term child development and midlife outcomes in Chinese contexts. Relative poverty in early life was a moderator that exacerbated the outcomes associated with childhood maltreatment.

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.

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.

Heterogeneous adverse childhood experiences and cognitive function in an elderly Chinese population: a cohort study

OBJECTIVE

To identify the heterogeneity of adverse childhood experiences (ACEs) as well as their association with cognitive function in an elderly Chinese population.

DESIGN

A retrospective cohort study.

PARTICIPANTS

The data were from the latest wave of the China Health and Retirement Longitudinal Study and a total of 7222 participants aged ≥60 were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Latent class analysis was used to identify the classes characterised by 11 types of ACEs. Cognitive function was measured by the Mini-Mental State Examination (MMSE) and cognitive impairment was defined by education-specific threshold MMSE scores. Logistic models were constructed to examine the relationship between ACE classes and cognitive impairment. Several childhood and adulthood confounding factors were considered.

RESULTS

Three ACE latent classes were identified. Of them, 76.09% were in the 'Low ACEs' class, 15.43% were in the 'Household dysfunction' class and 8.49% were in the 'Child maltreatment' class. The people in the 'Low ACEs' class seemed to have better childhood family financial situations and higher education levels. The population in the 'Household dysfunction' class tended to live in rural areas and have a higher proportion of men, whereas people in the 'Child maltreatment' class showed a significantly higher proportion of women and higher levels of chronic diseases. 'Child maltreatment' was related to a higher risk of cognitive impairment (OR=1.37, 95% CI: 1.12 to 1.68), while the risk of 'Household dysfunction' was not significantly different from that of the 'Low ACEs' participants (OR=1.06, 95% CI: 0.90 to 1.26).

CONCLUSIONS

The findings supported differences in cognitive function in elderly Chinese people exposed to different types of ACEs.

Race, Childhood Socioeconomic Status, and Region of Childhood Residence as Intersectional Life Course Predictors of Cognitive Aging in the U.S

Background and Objectives

Race, childhood socioeconomic status (cSES), and region of childhood residence are each associated with later life cognition, but no studies have examined how the confluence of these factors influence later life cognitive performance. Guided by intersectionality theory, we examined individuals’ social positionality across these dimensions as a predictor of cognitive performance in later life among non-Hispanic White (NHW) and Black (NHB) older adults.

Research Design and Methods

We used data from the 2010-2016 waves of the Health and Retirement Study (HRS) with participants ages 65 and older in 2010. We employed growth curve modeling to estimate associations among race, cSES and region of childhood residence, as well as their interactions, and cognitive performance at baseline and over time.

Results

Identifying as NHB, residing in the South, and having lower cSES each were associated with poorer later life cognition at baseline. Childhood residence in the South was an especially strong risk factor for poorer cognition among NHBs. Among NHWs, higher cSES was associated with better baseline cognitive performance, especially among those from the South. NHBs from the South demonstrated a small advantage of higher cSES, but regardless of cSES, NHBs from the South had lower levels of baseline cognitive scores compared to all other subgroups. We found that Southern childhood residence predicted faster rates of change in over a 6-year period.

Discussion and Implications

Our findings suggest that intersectional social positions across race, cSES, and region of childhood residence primarily influence baseline cognition in later life. Results implicate the importance of attention to multiple social positions in the context of racism within social policies and other initiatives to promote equity in life course brain health.

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.

Social Relationships in Early Life and Episodic Memory in Mid- and Late Life

OBJECTIVES

This study examines the longitudinal relationships between retrospective reports of early-life social relationships (i.e., having good friends, parent-child relationship quality, and childhood neighborhood social cohesion) and episodic memory in China.

METHODS

We analyzed 2 waves of data (2011 and 2015) from the China Health and Retirement Longitudinal Study. The analytical sample included 9,285 respondents aged 45 and older at baseline. A lagged dependent variable approach was used to estimate the associations between measures of early-life social relationships and episodic memory change at the study's 4-year follow-up.

RESULTS

Retrospective reports of better early-life social relationships are significantly associated with higher levels of episodic memory performance in 2015 among middle-aged and older Chinese, controlling for episodic memory in 2011, childhood socioeconomic status, adulthood sociodemographic variables, and the history of stroke. Educational attainment accounts for a significant portion of the associations between early-life social relationships and episodic memory. In contrast, mental health and social engagement in adulthood account for a small part of these associations.

DISCUSSION

The findings suggest that positive early-life social relationships are beneficial for episodic memory in mid- and late life, and more research is needed to examine the underlying mechanisms.

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.

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.

Life-course pathways from childhood socioeconomic status to type 2 diabetes in mid-late Chinese adulthood

The relationship between childhood socioeconomic status (SES) and type 2 diabetes (T2D) remains inconclusive, and the pathways and mechanisms driving this relationship have yet to be clarified. This study aimed to examine the pathways linking childhood SES to T2D prevalence in mid-late adulthood in a low- and middle-income country. The incidence of T2D diagnosed in mid-late Chinese adulthood was assessed using self-reports from the Health and Retirement Longitudinal Study (CHARLS). Childhood SES was assessed by the education, occupation, survivorship of the parents and the financial situation of the family, whereas adulthood SES was assessed by education and wage. This study performed structural equation modeling to clarify the direct and indirect pathways from childhood SES to T2D via childhood health, childhood food shortage, adulthood SES and physical activity. A total of 15,132 participants were included, and the prevalence of T2D was 5.24%. This study found that childhood SES was directly associated with T2D in mid-late adulthood, the probability of developing T2D increased by 9.20% of the standard deviation for each decrease in standard deviation in childhood SES. Childhood SES was indirectly associated with T2D via adulthood SES, physical activity, childhood health and food shortage. Adulthood SES and physical activity mainly mediated the indirect pathway from childhood SES and T2D. This study showed direct and indirect pathways from disadvantaged childhood SES to increased risk of T2D in mid-late Chinese adulthood. Childhood SES, adulthood SES, physical activity, childhood health and food shortage were identified as life-course interventional targets that should be considered in the development of effective strategies to reduce the burden of T2D and SES-related health inequities in childhood.

Sex Differences in Cognitive Health Among Older Adults in India

OBJECTIVES

To document sex differences in late-life cognitive function and identify their early-life determinants among older Indian adults.

DESIGN

Harmonized Diagnostic Assessment of Dementia for Longitudinal Aging Study in India (LASI-DAD).

SETTING

Individual cognitive testing in hospital or household setting across 14 states of India.

PARTICIPANTS

Individuals aged 60 years and older from LASI-DAD (2017-2019) (N = 2,704; 53.5% female).

MEASUREMENTS

Given the low levels of literacy and numeracy among older Indian adults, we consider two composite cognitive scores as outcome variables. Score I is based on tests that do not require literacy or numeracy, whereas score II is based on tests that require such skills. Ordinary least squares is used to estimate models featuring a progressively increasing number of covariates. We add to the baseline specification, including a sex dummy, age, and state indicators, measures of early-life socioeconomic status (SES), early-life nutrition, as proxied by knee height, and education.

RESULTS

Across most cognitive domains, women perform significantly worse than for men: -0.4 standard deviations (SD) for score I and -0.8 SD for score II. Early-life SES, health, and education explain 90% of the gap for score I and 55% for score II. Results are similar across hospital-based and home testing.

CONCLUSION

In India, lower levels of early-life human capital investments in nutrition and education among women compared with men are associated with a female disadvantage in late-life cognitive health. This has important implications for public health policy, aiming at reducing the risk of cognitive decline and dementia-a nascent concern in India. J Am Geriatr Soc 68:S20-S28, 2020.

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.

Baseline Infection Burden and Cognitive Function in Elders with Essential Tremor

Background

Patients with essential tremor (ET) have an increased risk of cognitive impairment, yet little is known about the predictors of cognitive decline in these patients. Exposures to infectious agents throughout the lifespan may impact the later development of cognitive impairment. For example, high Infection exposure has been associated with lower cognitive performance in Alzheimer's and Parkinson's disease. However, this predictor has not been examined in ET.

Objectives

To determine whether a higher baseline infection burden is associated with worse cognitive performance at baseline and greater cognitive decline over time in an ET cohort.

Method/Design

160 elderly non-demented ET participants (80.0 ± 9.5 years) underwent an extensive cognitive evaluation at three time points. At baseline, participants completed an infection burden questionnaire (t-IBQ) that elicited information on previous exposure to infectious agents and number of episodes per disease. Analysis of covariance and generalized estimated equations (GEEs) were used.

Results

Overall, infection burden was not associated baseline cognitive performance. Adjusted GEE models for repeated measures yielded a significant time interaction between moderate infection burden at baseline and better performance in the attention domain over time (p = 0.013). Previous history of rubella was associated with faster rate of decline in visuospatial performance (p = 0.046).

Conclusion

The data were mixed. Moderate self-reported infection burden was associated with better attention performance over time. Self-reported history of rubella infection was related to lower visuospatial performance over time in this cohort. Follow-up studies with additional design elements would be of value.

The association between childhood conditions and heart disease among middle-aged and older population in China: a life course perspective

Background

Heart disease is a severe health problem among adult populations in China. The prevalence rates of heart disease increase with age. The pathogenic causes of heart disease are often related to conditions in early life. Using a nationally representative sample of adults aged 45 or older in China, we examined the association between childhood conditions and heart disease in later life from a life course perspective.

Methods

The data used in this study were derived from the life history module and 2015 wave of China Health and Retirement Longitudinal Study (CHARLS). Missingness were handled by multiple imputation, generating 20 complete datasets with a final sample of 19,800. Doctor-diagnosed heart disease was the main dependent variable. Respondents’ conditions in childhood, adulthood, and older age were the independent variables (e.g., socioeconomic status, health, and health resources). Random-effects logistic regression models were conducted to test the hypotheses.

Results

A total of 16.6% respondents reported being diagnosed with heart disease by doctors. Regarding childhood socioeconomic status, 8.2% of the respondents considered that they were (a lot) better off than their neighbors, and 31.1% considered that their health status in childhood was better than their peers. More than 90% of respondents did not have severe illnesses during their childhood, and around 80.3% had access to health resources nearby in childhood. Lower socioeconomic status and poorer health conditions in childhood were associated with a greater likelihood of reporting doctor-diagnosed heart diseases, even after controlling for conditions in adulthood and older age (socioeconomic status: odds ratio (OR) = 0.947; self-rated health: OR = 0.917; severe illnesses: OR = 1.196).

Conclusions

Along with chronic diseases (e.g., hypertension, diabetes, and dyslipidemia), unhealthy behaviors, overweight and obesity, poor childhood conditions should be considered as screening criteria to identify populations at risk of heart disease. Relevant preventive strategies and interventions should be developed from a life course perspective and conducted in communities by providing health education program among older population with low socioeconomic status, and encouraging early detection and treatment.

Understanding Health and Social Challenges for Aging and Long-Term Care in China

The second King's College London Symposium on Ageing and Long-term Care in China was convened from 4 to 5th July 2019 at King's College London in London. The aim of the Symposium was to have a better understanding of health and social challenges for aging and long-term care in China. This symposium draws research insights from a wide range of disciplines, including economics, public policy, demography, gerontology, public health and sociology. A total of 20 participants from eight countries, seek to identify the key issues and research priorities in the area of aging and long-term care in China. The results published here are a synthesis of the top four research areas that represent the perspectives from some of the leading researchers in the field.

Early Child-Parent Relationship Quality and Cognitive Function in Older Rural Chinese Adults: The Mediating Role of Educational Attainment

Objectives: Framed within a life course perspective and cognitive reserve theory, this study examined the mediating role of educational attainment for the association between child-parent relationships during childhood and cognitive function among older adults in rural China. Methods: Data were obtained from three waves of the China Health and Retirement Longitudinal Study (N = 9809). We employed latent growth curve modeling to test the association among early child-parent relationship quality, educational attainment, and cognitive function in later life. Results: Early child-mother relationship quality was associated with the level and change in cognitive function. Early child-father relationship quality was only related to baseline cognitive function. Educational attainment mediated the relationship between early child-parent relationship quality with mothers and fathers and cognitive function. Discussion: Parental relationship experience in childhood was one distal factor related to cognitive function among older adults. The findings supported the long-term impacts of childhood conditions for later life health consequences.

Childhood cognitive skill trajectories and suicide by mid-adulthood: an investigation of the 1958 British Birth Cohort

BACKGROUND

Poor cognitive abilities and low intellectual quotient (IQ) are associated with an increased risk of suicide attempts and suicide mortality. However, knowledge of how this association develops across the life-course is limited. Our study aims to establish whether individuals who died by suicide by mid-adulthood are distinguishable by their child-to-adolescence cognitive trajectories.

METHODS

Participants were from the 1958 British Birth Cohort and were assessed for academic performance at ages 7, 11, and 16 and intelligence at 11 years. Suicides occurring by September 2012 were identified from linked national death certificates. We compared mean mathematics and reading abilities and rate of change across 7-16 years for individuals who died by suicide v. those still alive, with and without adjustment for potential early-life confounding factors. Analyses were based on 14 505 participants.

RESULTS

Fifty-five participants (48 males) had died by suicide by age 54 years. While males who died by suicide did not differ from participants still alive in reading scores at age 7 [effect size (g) = -0.04, p = 0.759], their reading scores had a less steep improvement up to age 16 compared to other participants. Adjustments for early-life confounding factors explained these differences. A similar pattern was observed for mathematics scores. There was no difference between individuals who died by suicide v. participants still alive on intelligence at 11 years.

CONCLUSIONS

While no differences in tests of academic performance and IQ were observed, individuals who died by suicide had a less steep improvement in reading abilities over time compared to same-age peers.

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

BACKGROUND

Cumulative evidence suggests that health-related risk factors during midlife and old-age are associated with cognitive impairment. However, studies are needed to clarify the association between early-life risk factors and impaired cognitive functioning to increment existing knowledge.

OBJECTIVE

To examine the association between childhood infectious diseases and late-life cognitive functioning in a nationally representative sample of older adults.

PARTICIPANTS

Eligible respondents were 2994 community-dwelling individuals aged 65-85.

MEASUREMENTS

Cognitive functioning was assessed using the Mini-Mental State Examination (MMSE). Childhood infectious diseases (i.e. chicken pox, measles, and mumps) were self-reported. The study covariates were age, sex, highest educational level achieved, smoking status, body mass index, and depression. The primary statistical analysis examined the association between the number of childhood infectious diseases and total MMSE scores, accounting for all study covariates. Regression models of progressive complexity were examined for parsimony. The robustness of the primary results was tested in 17 sensitivity analyses.

RESULTS

The most parsimonious model was a linear adjusted model (Bayesian Information Criterion = 12646.09). Late-life cognitive functioning significantly improved as the number of childhood infectious diseases increased (β = 0.18; 95% CI = 0.11, 0.26; p < 0.001). This effect was not significantly attenuated in all sensitivity analyses.

CONCLUSION

The current study results are consistent with prior ecological findings indicating that some childhood infectious diseases are associated with better cognitive functioning in old-age. This points to an early-life modifiable risk factor associated with older-life cognitive functioning. Our results may reflect selective mortality and/or beneficial effects via hormetic processes.

The impact of childhood experience of starvations on the health of older adults: Evidence from China

This paper used pooled cross-sectional data from the Chinese Longitudinal Healthy Longevity Survey to comprehensively investigate how childhood experiences of starvation affect the health of older Chinese adults. The study found that the childhood experience of starvation was negatively correlated with self-rated health, functional health and cognitive health among older adults. After using the model and variable substitution methods to address the endogeneity problems caused by omitted variables, the negative effects of childhood experiences of starvation on the health of older adults were still present. The Karlson-Holm-Breen decomposition method was used to test the mediation effects, and it was found that childhood experiences of starvation had adverse effects on the health of older adults through endowment insurance, household income, education and nutrition. Consequently, the government should strengthen nutrition or other related health interventions for children and make longer-term plans for improving the health of older adults.

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

BACKGROUND AND OBJECTIVES

This study investigated the relationship between childhood friendships and cognitive functioning, as assessed with cognitive status and decline among adults aged 45 and older in China. We also examined the mediating effect of adult social disconnectedness and adult loneliness for this relationship.

RESEARCH DESIGN AND METHODS

This study was based on 3 waves of data from the China Health and Retirement Longitudinal Study (CHARLS; 2011, 2013, 2015; N = 13,959). Cognitive functioning was assessed with episodic memory. Childhood friendship measures were taken from the 2014 life history module of the CHARLS. Two dimensions of adult social isolation, loneliness and social disconnectedness, were included as mediators. Latent growth curve modeling was utilized to test the associations between childhood friendships, adult social isolation, and cognitive functioning.

RESULTS

Adverse childhood friendship experiences were found to be significantly associated with both lower initial cognitive status and the rate of decline in cognitive functioning. Our findings indicated that adult loneliness and social disconnectedness partly mediated the link between childhood friendship experiences and the initial level of cognitive functioning, but not cognitive decline later in life.

DISCUSSION AND IMPLICATIONS

The findings emphasized the enduring importance of childhood friendships for cognitive functioning later in life. Interventions that focus on improving social participation through fostering friendships in childhood may have long-term benefits for cognition later in life.

Does early peer relationship last long? The enduring influence of early peer relationship on depression in middle and later life

BACKGROUND

Previous studies focus on the health effect of early family relationship rather than early peer relationship. Thus, this study aimed to examine the causal effect of early peer relationship on depression in middle and later life.

METHODS

Based on the China Health and Retirement Longitudinal Study data 2013-2014 (N = 15,343), this study used the propensity score matching approach to estimate the causal effect of early peer relationship, including establishment (whether having good friends in childhood), engagement (frequency of playing with friends in childhood) and feeling (feeling of loneliness in childhood), on depression in middle and later life, as well as the educational heterogeneity of this health effect.

RESULTS

Elevated feeling of loneliness and reduced engagement of early peer relationship were causally related to elevated depression in middle and later life, but having good friends in childhood was not related to later life depression. For individuals with more education, less feeling of loneliness in childhood had a stronger effect on reduced depression in middle and later life, but more engagement in childhood peer relationship only had a weaker effect on reduced depression in middle and later life.

LIMITATIONS

A retrospective survey and single-item measures of early peer relationship were used, the intermediate link across the life course and potential neurobiological mechanisms were also not empirically examined.

CONCLUSIONS

We should focus more on the engagement and quality of early peer relationship, as well as the balance between education and socializing in childhood, to prevent from the detrimental health effect of early peer relationship disadvantage.

Childhood Socioeconomic Status and Cognitive Function Later in Life: Evidence From a National Survey in Indonesia

INTRODUCTION

Social and economic conditions in childhood have been found to predict cognitive ability in midlife and old age in high-income countries. This study examines the long-term effect of childhood conditions on cognition among a nationally representative sample of older adults in a low- and middle-income country.

MATERIALS AND METHODS

Data were obtained from the 2014 to 2015 Indonesia Family Life Survey Wave 5 (6676 respondents, aged 50 years and older). Cognitive function was assessed based on total score on a series of tests adapted from the Telephone Interview for Cognitive Status. Retrospective information was collected on childhood poverty, with questions including whether respondents ever experienced hunger before age 15, whether basic facilities were available, and the number of books in the childhood home. We used linear regression to examine the association between childhood conditions and cognitive function in later life.

RESULTS

The findings show that the numbers of facilities and books available in childhood homes are substantially associated with cognition in later life after taking adulthood characteristics into account. Childhood hunger has no significant association with cognitive ability in later life. Belonging to an older birth cohort and living in a rural area were shown to have negative associations with cognitive ability in Indonesia.

CONCLUSIONS

Our findings suggest that childhood poverty, birth cohort, and living in a rural area may contribute to cognitive aging in Indonesia. Policies and interventions that target childhood poverty in developing countries may also recognize the rural-urban divide in access to educational and other socioeconomic resources.

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.

Life Course Pathways From Childhood Socioeconomic Status to Later-Life Cognition: Evidence From the Wisconsin Longitudinal Study

OBJECTIVES

A growing body of research indicates that older adults are at greater risk for poorer cognition if they experienced low socioeconomic status (SES) as children. Guided by life course epidemiology, this study aimed to advance understanding of processes through which childhood SES influences cognition decades later, with attention to the role of scholastic performance in adolescence and SES in midlife.

METHOD

We used data from the Wisconsin Longitudinal Study (WLS), which has followed a cohort of high school graduates since they were 18 years old in 1957. Childhood SES was measured prospectively in adolescence, and measures of memory and language/executive functioning were based on neurocognitive assessments at age 72. We used participants' scores on a statewide standardized test in high school as an indicator of scholastic performance in adolescence. The measure of SES in midlife included years of postsecondary education, income, and occupation status at age 53.

RESULTS

Findings from structural equation models indicated that scholastic performance in adolescence and midlife status attainment together fully mediated associations between childhood SES and both memory and language/executive functioning at age 72. Adolescent scholastic performance was directly associated with later-life cognition, as well as indirectly through midlife status attainment.

DISCUSSION

Findings provide support for both latency and social pathway processes when considering how SES in childhood influences later-life cognition. Results contribute to growing calls for social policies and programs to support optimal brain health at multiple phases throughout the life course, especially among individuals with lower SES as children.

Early-life socioeconomic status, adolescent cognitive ability, and cognition in late midlife: Evidence from the Wisconsin Longitudinal Study

Although the association between childhood socioeconomic status (SES) and late-life cognition is well-established, the mechanisms underlying this association are less clear. One important potential mediator seldom examined is adolescent cognitive ability. To address this gap, we examined 5,880 respondents from the Wisconsin Longitudinal Study, which follows a random sample of high school students who graduated from Wisconsin high schools in 1957. Structural equation models were used to examine the direct and indirect effects of childhood SES on cognition in late midlife through adolescent cognitive ability, educational attainment, midlife economic condition, and midlife health. Cognitive function was measured as a latent variable composed of scores from 6 cognitive assessments including immediate and delayed recall, digit ordering, letter and category fluency, and a subset of the Wechsler Adult Intelligence Scale similarities test. We found that childhood SES predicts cognition in late midlife, and this association is largely mediated by adolescent cognitive ability and educational attainment and to a lesser extent by midlife economic condition and health. The findings underscore the long-arm of childhood SES in cognitive function in later life and highlight the complex life-course pathways underlying the association between childhood SES and cognition.

Temporal precedence of cognitive function and functional abilities: A latent difference score model of the Chinese community-dwelling elders

OBJECTIVES

Little research has explored how cognitive function and activities of daily living (ADL) affect each other over time. In addition, no current finding provides a clear hint to the temporal precedence between them. The present study tries to address these limitations of prior studies by utilizing a longitudinal data and advanced statistical modeling.

METHODS

This study analyzed the data from the China Health and Retirement Longitudinal Study (CHARLS), a prospective observational study performed every 2 years for a total of three waves between 2011 and 2015 using a multistage probability sampling. Cognitive function was measured on the basis of three aspects of cognitive performance. Functional abilities were assessed using six types of activities of ADL and five types of instrumental ADL (IADL). Latent difference score modeling was employed to investigate the temporal precedence between cognitive function and ADL.

RESULTS

The best fitting model indicates poor cognitive function precede worsening in ADL function, whereas the current findings did not support that poor ADL predate the cognition decline or reciprocal influence hypotheses.

CONCLUSIONS

The elderly with poor cognitive function may be more vulnerable to deterioration in ADL. Findings underscore the importance of early screening for cognitive function among the elderly as the key strategy to prevent further ADL impairment and keep independence.

Childhood Socioeconomic Status and Later Life Cognition: Evidence From the Wisconsin Longitudinal Study

Objectives:This study examined childhood socioeconomic status (SES) as a predictor of later life cognition and the extent to which midlife SES accounts for associations. Methods: Data came from 5,074 participants in the Wisconsin Longitudinal Study. Measures from adolescence included parents' educational attainment, father's occupational status, and household income. Memory and language/executive function were assessed at ages 65 and 72 years. Results: Global childhood SES was a stronger predictor of baseline levels of language/executive function than baseline memory. Associations involving parents' education were reduced in size and by statistical significance when accounting for participants' midlife SES, whereas associations involving parental income and occupational status became statistically nonsignificant. We found no associations between childhood SES and change in cognition. Discussion: Findings contribute to growing evidence that socioeconomic differences in childhood have potential consequences for later life cognition, particularly in terms of the disparate levels of cognition with which people enter later life.

Cardiometabolic Risk and Cognitive Decline: The Role of Socioeconomic Status in Childhood and Adulthood

Socioeconomic conditions in childhood predict cognitive functioning in later life. It is unclear whether poor childhood socioeconomic status (SES) also predicts the acceleration of cognitive decline. One proposed pathway is via cardiometabolic risk, which has been linked to both childhood SES and earlier onset of cognitive impairment. Using data from the Health and Retirement Study, we examine the impact of childhood SES on cognitive trajectories over six years and test whether it operates through increased cardiometabolic risk and adult SES. We find that higher childhood SES leads to slower cognitive decline, partially due to lower levels of cardiometabolic risk. However, these pathways operate entirely through adult socioeconomic attainment. The results have important implications for future trends in cognitive population health within the context of growing social inequality and reduced social mobility.

Domains of Childhood Disadvantage and Functional Limitation Trajectories Among Midlife Men and Women in China

Objective: To examine the impacts of four childhood disadvantage domains-parental behavior, hunger, health, and socioeconomic status (SES)-on functional limitation trajectories among midlife adults in China. Method: Data (2011-2015) from the China Health and Retirement Longitudinal Study (N = 8,646) were used to examine the associations between different domains of childhood disadvantage and functional limitation trajectories among adults aged 45 to 64. Results: Adverse parental behavior was not associated with baseline functional limitation but was associated with steeper trajectories for men. Health, hunger, and SES were associated with more functional limitations at baseline, and SES with steeper trajectories for men and women. Adulthood SES largely accounted for the associations between childhood SES and functional limitations for men. Discussion: It is important to examine multiple domains of childhood conditions because the type and magnitude of disadvantage may influence functional limitations in different ways among men and women in China.