Association of perceived childhood socio-economic status and health with depressive symptoms among middle-aged and older adults in India: using data from LASI Wave I, 2017-2018

BACKGROUND

Childhood adverse experience has been linked with poor health outcomes across the life course. Nevertheless, whether such an association or direction could be projected to older people's life remains still unclear and needs to generate more evidence, particularly in India. Therefore, this study was conducted to examine the association of childhood socio-economic status and health with depressive symptoms amongst middle- aged and older adults in India.

METHODS

The data for the study was drawn from national representative survey "Longitudinal Ageing Study in India (LASI)" Wave I, 2017-2018 in order to conduct cross-sectional study. Multivariable regression analysis was used to examine the association of childhood socioeconomic status and health with depressive symptoms in the older population.

RESULTS

Poor childhood health was significantly and positively associated with depressive symptoms (AoR: 1.56, CI: 1.19, 2.04). Likewise, respondents who were bedridden for a month during their childhood had high odds of developing depressive symptoms (AoR: 1.16 CI: 1.01, 1.34). In addition to this, the odds of having depressive symptoms increased significantly among the average (AoR: 1.28 CI: 1.08, 1.51) and poor childhood socioeconomic status group (AoR: 1.31 CI: 1.11, 1.55) as compared to the higher socioeconomic category.

CONCLUSIONS

Childhood socioeconomic status and health have a significant role in determining mental health in later life. Results suggest that considering childhood socioeconomic status and health is important while diagnosing depression in older population in order to identify the significant associated factors in early childhood and thus help in preventing depressive symptoms in later life.

Childhood circumstances, social mobility and the obesity transition: Evidence from South Africa

The distribution of obesity tends to shift from rich to poor individuals as countries develop, in a process of shifting sociodemographic patterns of obesity that has been called the 'obesity transition'. This change tends to happen with economic development, but little is known about the specific mechanisms that drive the change. We propose that improvements in childhood circumstances with economic development may be one of the drivers of the obesity transition. We explore whether the social gradient in body weight differs by childhood socioeconomic status (SES), proxied by the respondent's mother having Grade 12, using South Africa's nationally representative panel National Income Dynamics Study. In support of our hypothesis, we find that the social gradient in body weight is less positive for adults who had a high childhood SES, and already appears to have reversed among high-SES women who also had a high childhood SES. Upward social mobility over an individual's life course or across a single generation is associated with higher body weight compared to a stable high SES. But a high SES sustained in childhood and adulthood - or across more than one generation - may decrease adult obesity risk, and result in a reversal of the social gradient in body weight. Random effects within-between models show that the social gradient in body weight and its interaction with childhood SES are driven more by differences in income between individuals than by short-run changes in income within individuals, again suggesting that the obesity transition is driven by long-run changes rather than by very short-run changes. Our results are broadly robust to using several alternative measures of body weight, childhood SES and adult SES. Our results are consistent with the hypothesis that widespread improvements in childhood circumstances and nutrition with economic development may contribute to the shift to later stages of the obesity transition.

Heterogenous trajectories in physical, mental and cognitive health among older Americans: Roles of genetics and life course contextual factors

We investigate the roles of genetic predispositions, childhood SES and adult educational attainment in shaping trajectories for three important components of the overall health of older adults -- BMI, depressive symptoms and cognition. We use the Health & Retirement Study (HRS) and group-based trajectory modeling (GBTM) to identify subgroups of people who share the same underlying trajectories ages 51-94 years. After identifying common underlying health trajectories, we use fractional multinomial logit models to estimate associations of (1) polygenic scores for BMI, depression, ever-smoked, education, cognition and subjective wellbeing, (2) childhood SES and (3) educational attainment with the probabilities of trajectory group memberships. While genetic predispositions do play a part in predicting trajectory group memberships, our results highlight the long arm of socioeconomic factors. Educational attainment is the most robust predictor-it predicts increased probabilities of belonging to trajectories with BMI in the normal range, low depressive symptoms and very-high initial cognition. Childhood circumstances are manifested in trajectories to a lesser extent, with childhood SES predicting higher likelihood of being on the low depressive symptoms and very-high initial cognition trajectories. We also find suggestive evidence that associations of educational attainment on the probabilities of being on trajectories with BMI in the normal range, low depressive symptoms and very-high initial cognition vary with genetic predispositions. Our results suggest that policies to increase educational attainment may improve population health by increasing the likelihood of belonging to "good" aging trajectories.

Parental Education and Delirium Risk after Surgery in Older Adults

OBJECTIVES

Efforts to conceptualize risk factors for postoperative delirium in older adults have focused on the time proximate to the episode, but how early-life exposures influence delirium risk is poorly understood.

METHODS

An observational cohort of 547 patients aged 70+undergoing major non-cardiac surgery at two academic medical centers in Boston. Demographic characteristics, cognition, parental education, health, and participation in cognitively stimulating activities were assessed prior to surgery. Delirium incidence and severity were measured daily during hospitalization.

RESULTS

Higher paternal education was associated with significantly lower incidence of delirium (X2(1, N =547)=8.35, p <.001; odds ratio OR=.93, 95% CI, .87 to .98) and inversely associated with delirium severity (r(545)=-.13, p <.001). Higher maternal education was associated with lower delirium incidence but did not reach statistical significance. The effect of paternal education on delirium incidence was independent of the patient's education, estimated premorbid intelligence, medical comorbidities, neighborhood disadvantage, and participation in cognitively stimulating activities (X2(2, N =547)=31.22, p <.001).

CONCLUSIONS

Examining early-life exposures may yield unique insights into the risks and pathogenesis of delirium.

CLINICAL IMPLICATIONS

Evaluating long-term factors that increase vulnerability to delirium may improve our ability to calculate risk. It may guide clinical decision-making and inform pre- and post-operative recommendations.

The effect of childhood socioeconomic status on depressive symptoms in middle-old age: the mediating role of life satisfaction

BACKGROUND

Some studies have shown that childhood socioeconomic status (SES) can influence the development and progression of depression in adulthood. This study aimed to analyze the effects of childhood SES on depressive symptoms in individuals of middle-old age and examine the potential mediating role of life satisfaction based on national data in China.

METHODS

Data were derived from the 2018 China Health and Retirement Longitudinal Study (CHARLS) data. A total of 17,129 individuals who were aged 45 years and older were included. The dependent variable was depressive symptoms in middle-old age. Childhood SES was the independent variable, and life satisfaction was the mediator. This study controlled four factors: general demographic characteristics, adult SES, childhood adversity and health and living status. Pearson correlations and hierarchical multiple regression analysis were performed, and the Baron and Kenny method was used to test the mediating role.

RESULTS

The score of depressive symptoms among all participants was 7.88 ± 6.65. Gender, age, adult SES, childhood adversity and health and living status all affected the development of depression symptom in middle-aged and elderly individuals in China. After adjusting for all covariates, the higher the childhood SES, the lower the depressive symptom score (β = - 0.422, P < 0.001). Life satisfaction had a partial mediating effect between childhood SES and depressive symptoms. Low childhood SES may improve life satisfaction (β = 0.051, P < 0.001) and life satisfaction indirectly decreases depressive symptom scores (β = - 0.403, P < 0.001).

CONCLUSIONS

Life satisfaction was a partial mediator between childhood SES and depressive symptoms in middle and old age. Improving life satisfaction may serve as an intervention to reduce the incidence of depression symptoms in the future.

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 Childhood Socioeconomic Status with Leukocyte Telomere Length Among African Americans and the Mediating Role of Behavioral and Psychosocial Factors: Results from the GENE-FORECAST Study

Purpose

We examined if childhood socioeconomic status (SES) was related to adult leucocyte telomere length (TL) using the data of 361 African American (AA) participants from the GENE-FORECAST Study. We also assessed the mediating role of behavioral and psychosocial factors in the association between childhood SES and adult TL.

Methods

Childhood SES was assessed individually by using participant’s mother’s education and occupation, father’s education and occupation, parental home ownership, and family structure. TL was assessed using the quantitative polymerase chain reaction method. Information on potential confounders and mediators were collected. The associations of childhood SES with TL were assessed using multivariable linear regression models. We used path analysis to quantify and test the share of these associations that was statistically explained by each of the mediators (participant’s educational attainment, smoking status, physical activity, dietary habit, perceived stress, and depressive symptoms).

Results

Mother’s education was associated with longer average TL (β: 0.021; 95% CI: 0.001, 0.04, p=0.038) in confounder adjusted models. Once mediators were introduced in the model, the estimates were reduced and remained marginally significant (β: 0.017; 95% CI: −0.003, 0.038, p=0.061). According to path model, approximately 19% of the effect of mother’s education on TL (β: 0.004; 95% CI: −0.001, 0.01, p < 0.10) was mediated through participant’s own education level. No significant mediation effect was observed for any other mediators.

Conclusions

These data provide evidence that participant’s mother’s education was positively linked to adult TL in AA population. Participant’s own educational level partially explained this association.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40615-021-01040-5.

The association between childhood socioeconomic status and adult health behavior: The role of locus of control

The socioeconomic environment in childhood is a powerful determinant for health behavior in adulthood, subsequently influencing health outcomes. However, the underlying mechanisms are insufficiently understood. This study assesses locus of control (LOC) as a mediator linking childhood socioeconomic status (SES) with health behavior (smoking, regular alcohol consumption, unhealthy diet and low physical activity). Drawing on a representative sample from Germany (SOEP), we investigated these relations using structural equations modelling. Results show that externally oriented LOC explains up to 6% of the relationship between childhood SES and health behavior in adulthood, independently from adult SES. Stratification indicates that these results hold in women but not in men, in younger and middle-aged individuals but not in older ones. Hence, control beliefs play a modest yet significant role in shaping the socioeconomic gradient in health behavior and might have far-reaching consequences on how morbidity and mortality arise and persist across generations.

Scars of childhood socioeconomic stress: A systematic review

Childhood socioeconomic position (SEP) is associated with the development of adult psychological outcomes, with DNA methylation (DNAm) as a mechanism to potentially explain these changes. We present the first systematic review synthesising the literature investigating childhood SEP and DNAm. Thirty-two publications were included. Seventeen studies focused on candidate genes, typically focusing on genes implicated with the stress response and/or development of psychiatric conditions. These studies typically investigated different regions of the genes, which revealed inconsistent results. Six studies calculated epigenetic age, with a small number revealing an elevated significant association with childhood SEP. Epigenome-wide studies revealed altered patterns of DNAm which varied between the nine studies. This research area is emerging and demonstrated great variance in findings with no clear patterns identified across studies. Multiple methodological shortcomings are identified, including at the phenotypic level where construct validity of childhood SEP is highly inconsistent, with studies using a wide range of measures. Larger cohorts will be required with international collaborations to strengthen this research area.

Looking homeward with the life course: Early origins of adult dwelling satisfaction?

The long-term influence of childhood economic and social exposures on adult health and well-being is well-known. Most childhood circumstances transpire in or near the home, yet research has largely neglected how early exposures shape people's experience of their residential context in adulthood. To help address this gap, we use retrospective longitudinal data from the Midlife Development in the United States (MIDUS) study. Drawing on a life course framework, we test the potential mediating roles of adult social, economic, and mental health processes. Results suggest that childhood parental warmth and maltreatment have an enduring influence on people's satisfaction with their adult home, while there is little indication that childhood economic conditions shape adult dwelling satisfaction. Analyses of average controlled direct effects suggest that the effects of childhood parental warmth are mediated slightly by adult socioeconomic attainment and psychological adjustment but especially by supportive family relationships during adulthood. This pattern is consistent with an attachment-based interpretation of the importance of childhood conditions for adult relationships as well as home satisfaction. Taken together, our results suggest that parent-child bonds cast a long shadow over how people experience their residential context decades later, through a diffuse, multifaceted set of intervening pathways.

Social engagement in late life may attenuate the burden of depressive symptoms due to financial strain in childhood

BACKGROUND

It remains poorly understood if childhood financial strain is associated with old-age depression and if active social life may mitigate this relationship.

AIMS

To investigate the association between childhood financial strain and depressive symptoms during aging; to examine whether late-life social engagement modifies this association.

METHOD

2884 dementia-free individuals (aged 60+) from the Swedish National study of Aging and Care-Kungsholmen were clinically examined over a 15-year follow-up. Presence of childhood financial strain was ascertained at baseline. Depressive symptoms were repeatedly assessed with the Montgomery-Åsberg Depression Rating Scale. Social engagement comprised information on baseline social network and leisure activities. Linear, logistic and mixed-effect models estimated baseline and longitudinal associations accounting for sociodemographic, clinical, and lifestyle factors.

RESULTS

Childhood financial strain was independently associated with a higher baseline level of depressive symptoms (β = 0.37, 95%CI 0.10-0.65), but not with symptom change over time. Relative to those without financial strain and with active social engagement, depressive burden was increased in those without financial strain but with inactive social engagement (β = 0.43, 95%CI: 0.15-0.71), and in those with both financial strain and inactive engagement (β = 0.99, 95%CI: 0.59-1.40). Individuals with financial strain and active social engagement exhibited similar depressive burden as those without financial strain and with active social engagement.

LIMITATIONS

Recall bias and reverse causality may affect study results, although sensitivity analyses suggest their limited effect.

CONCLUSIONS

Early-life financial strain may be of lasting importance for old-age depressive symptoms. Active social engagement in late-life may mitigate this association.

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.

Scarcity or luxury: Which leads to adolescent greed? Evidence from a large-scale Chinese adolescent sample

INTRODUCTION

Because greed is associated with various destructive outcomes, understanding the developmental precursors to dispositional greed in adolescence is of great importance. However, there are few empirical studies on this topic. The current study aimed to examine the relationship between childhood socioeconomic status (CSES) and adolescent greed and the moderating effect of family size. Two competing hypotheses were proposed. One is the scarcity hypothesis, which claims that CSES may be negatively related to adolescent greed. Another is the luxury hypothesis, which proposes that the richer the environment one grew up in, the more likely one is to develop dispositional greed.

METHOD

A cross-sectional sample of 3,200 adolescents (11-19 years old, 1,712 females, 1,356 males, and 132 of unknown gender) from North, Northwest, Middle and South China completed the questionnaire sets. A hierarchical multiple regression analysis was conducted.

RESULTS

CSES was positively correlated with dispositional greed, and the moderating effect of family size was significant.

CONCLUSION

The current study provides evidence supporting the luxury hypothesis over the scarcity hypothesis. In addition, adolescent dispositional greed increases with an increase in CSES when there is only one child in the family, while this is not the case for children with siblings. The theoretical and practical implications of the current study results as well as future research directions are discussed.

Racial Differences in Mechanisms Linking Childhood Socioeconomic Status With Growth in Adult Body Mass Index: The Role of Adolescent Risk and Educational Attainment

PURPOSE

The present study examined whether risk factors during adolescence, including substance use, depression, overweight status, and young adult educational attainment, mediated the association between low childhood socioeconomic status (SES) and higher body mass index (BMI) in adulthood. We also evaluated whether the hypothesized pathways differed based on racial group status.

METHODS

Participants from the Seattle Social Development Project were followed from ages 10 to 39years. Thepresent study included white (n = 381), African American (n = 207), and Asian American (n = 171) participants. Structural equation models tested pathways linking low childhood SES to BMI from ages 24 to 39 years. Multiple-group modeling was used to test potential racial differences.

RESULTS

Analyses indicated racial differences in the pathways linking low childhood SES with adult BMI. For whites, overweight status and educational attainment were significant mediators. For Asian Americans, there was an unmediated and significant pathway between low childhood SES and low adult BMI. For African Americans, there were no significant mediated or unmediated pathways.

CONCLUSIONS

Results stress that the pathways that link childhood SES with adult BMI may operate differently based on race. Research is particularly needed to identify mechanisms for African Americans in order to better inform obesity prevention efforts.

Childhood socioeconomic status and longitudinal patterns of alcohol problems: Variation across etiological pathways in genetic risk

Childhood socioeconomic status (SES) is an important aspect of early life environment associated with later life health/health behaviors, including alcohol misuse. However, alcohol misuse is modestly heritable and involves differing etiological pathways. Externalizing disorders show significant genetic overlap with substance use, suggesting an impulsivity pathway to alcohol misuse. Alcohol misuse also overlaps with internalizing disorders, suggesting alcohol is used to cope. These differing pathways could lead to different patterns over time and/or differential susceptibility to environmental conditions, such as childhood SES. We examine whether: 1) genetic risk for externalizing and internalizing disorders influence trajectories of alcohol problems across adolescence to adulthood, 2) childhood SES alters genetic risk these disorders on trajectories of alcohol problems, and 3) these patterns are consistent across sex. We find modest evidence of gene-environment interaction. Higher childhood SES increases the risk of alcohol problems in late adolescence/early adulthood, while lower childhood SES increases the risk of alcohol problems in later adulthood, but only among males at greater genetic risk of externalizing disorders. Females from lower SES families with higher genetic risk of internalizing or externalizing disorders have greater risk of developing alcohol problems.

Early life socioeconomic status associates with interleukin-6 responses to acute laboratory stress in adulthood

It is proposed that environmental exposures in early life influence immune programming. Specifically, socioeconomic disadvantage is thought to program an immune phenotype that is prone to inflammation and associated with increased risk for inflammatory disease later in life. Existing literature shows an inverse association of early childhood socioeconomic status (SES) with adult levels of systemic inflammation. Here, we extend that literature to examine whether early childhood SES also relates to the magnitude of inflammatory response to acute psychological stress in adulthood. Healthy volunteers (N = 110; 40-58 years; 59% female; 90% white) performed a laboratory stress protocol, with blood samples drawn at the end of a 30-min baseline, a 5-min speech task, and a 30-min recovery to assess interleukin (IL)-6 stress responses. An early childhood SES index was derived from reports of parental home and vehicle ownership, and number of bedrooms per child in the home across ages 1-2, 3-4, and 5-6. Regressions adjusted for current age, sex, race, and BMI showed that lower SES at age 1-2 was associated with larger IL-6 stress responses in adulthood (ΔR² = 0.05, β = -0.24, p = .03). This association was independent of adult SES and task-evoked affective responses. No association was found between SES at ages 3-4 or 5-6 and IL-6 responses. These results provide initial evidence for a link between disadvantage in the first 2 years of life and heightened inflammatory response to stress in adulthood; this link may contribute to the increased disease risk that accompanies being raised in disadvantaged socioeconomic circumstances.

The potential protective effect of friendship on the association between childhood adversity and psychological distress in adulthood: A retrospective, preliminary, three-wave population-based study

BACKGROUND

Previous studies that assessed the mediating role of social support in the association between childhood adversity and psychological distress based their inferences on very small, selective samples, which makes it impossible to generalise the findings to general population. The aim of this paper was to assess the mediating role of quantity and quality of social support in adulthood in the association between childhood adversity and psychological distress in adulthood.

METHODS

The study has a three-wave design; the present analysis used longitudinal data collected from 1994 to 2008 within the framework of the Tromsø Study (N = 4530), a representative prospective cohort study of men and women. Quantity and quality of social support were measured at a mean age of 54.7 years, and psychological distress in adulthood was measured at a mean age of 61.7 years. Mediation analysis was used to assess the indirect effect of childhood adversity (via quantity and quality of social support) on psychological distress in adulthood.

RESULTS

Childhood adversity was associated with deficits in quantity and quality of social support in adulthood (p < 0.05). Childhood adversity and deficits in quantity and quality of social support were associated with psychological distress in adulthood (p < 0.05). Quantity and quality of social support significantly (p < 0.05) mediated the association between childhood adversity and psychological distress in adulthood.

LIMITATIONS

Childhood adversity was assessed retrospectively and social support was measured with two items.

CONCLUSION

Interventions aimed at reducing social isolation may alleviate the burden carried by survivors of childhood adversity.

Association between childhood socioeconomic status and fruit and vegetable intake among older Japanese: The JAGES 2010 study

Fruit and vegetable intake (FVI) contributes to the prevention of non-communicable diseases. Although food preference is considered to be determined early in life, few studies have investigated the association between childhood socioeconomic status (SES) and FVI in older age. Because a school lunch program was initiated in Japan after World War II, we were able in this study to examine this association in an older Japanese population. We used data from a population of physically and cognitively independent adults aged 65years or older who were living independently in the community and were recruited from 27 municipalities in the Japan Gerontological Evaluation Study 2010 project (August 2010-January 2012). Three categories of childhood SES (low, middle, and high) and current FVI were evaluated via a self-reported questionnaire. Poisson regression was used to investigate the association between childhood SES and FVI in 19,920 individuals. After adjustment for age and sex, older people with low childhood SES were 1.36 times more likely (95% CI 1.23-1.52) to have poor FVI than those with high childhood SES. In the fully adjusted model, the significant association disappeared. Further age-stratified analysis revealed a positive association between childhood SES and FVI among people aged 70-76years who were partially exposed to the school lunch program, but not among people aged 65-69years old who were fully exposed to the program. In conclusion, social policy such as school lunches targeting children with low SES could help improve FVI in old age.

Childhood adversities and chronic conditions: examination of mediators, recall bias and age at diagnosis

OBJECTIVES

The aim of this study was to (1) identify the influence of childhood socioeconomic status (CSES) on five chronic conditions: asthma, bronchitis, hypothyroid, migraine, and psychiatric disorders in later life; (2) determine the mediating role of childhood abuse (CA) in these associations, and (3) quantify recall bias due to respondent's mental health in these associations.

METHODS

10,325 men and women from the Tromsø Study were followed for 13 years, and Poisson regression models were used.

RESULTS

Low CSES was associated with a 16-23% higher risk of chronic conditions, and CA was associated with a 16-58% higher risk of chronic conditions (p < 0.05). A minor proportion of the association between CSES and CA (3.98%, p < 0.05); CSES and chronic conditions (5.54-8.71%, p < 0.05); and CA and chronic conditions (9.51-19.52%, p < 0.05), were driven by recall bias due to the respondent's mental health. CA mediated the association between CSES and chronic conditions (9.58-25.06%, p < 0.05).

CONCLUSIONS

Low CSES and CA are associated with higher risk of chronic conditions in later life. A minor proportion of these associations are driven by recall bias.

Childhood socioeconomic disadvantage is associated with lower mortality in older Japanese men: the JAGES cohort study

BACKGROUND

Childhood socioeconomic disadvantage has been previously linked to increased mortality risk in adulthood. However, most previous studies have focused on middle-aged adults in Western contexts. Here, we sought to examine the association between childhood socioeconomic status (SES) and mortality among healthy older Japanese adults.

METHODS

We conducted a 3-year follow-up of participants in the Japan Gerontological Evaluation Study (JAGES), a population-based cohort of 65- to 103-year-old Japanese adults. Childhood SES was assessed by survey at baseline. Mortality from 2010 to 2013 was analysed for 15 449 respondents (7143 men and 8306 women). Cox regression models were used to estimate hazard ratios (HR) for risk of death.

RESULTS

A total of 754 deaths occurred during the 3-year follow-up. Lower childhood SES was significantly associated with lower mortality in men, but not in women. Compared with men growing up in more advantaged childhood socioeconomic circumstances, the age-adjusted HR for men from low childhood SES backgrounds was 0.75 [95% confidence interval (CI): 0.56-1.00]. The association remained significant after adjustment for height, education, adult SES, municipalities of residence, health behaviours, disease status and current social relationships (HR = 0.64; 95% CI 0.47-0.87). This association was stronger among men aged 75 years or older, HR = 0.67 (95% CI: 0.47-0.95), compared with men aged 65-74 years, HR = 0.90 (95% CI: 0.54-1.51).

CONCLUSIONS

Childhood socioeconomic disadvantage is associated with lower mortality among men aged 75 years or older, which may be due to selective survival, or alternatively to childhood physical training or postwar calorie restriction in this generation of Japanese males.

Socioeconomic status across the life course and all-cause and cause-specific mortality in Finland

We used high quality register based data to study the relationship between childhood and adult socio-demographic characteristics and all-cause and cause-specific mortality at ages 35-72 in Finland among cohorts born in 1936-1950. The analyses were based on a 10% sample of households drawn from the 1950 Finnish Census of Population with the follow-up of household members in subsequent censuses and death records beginning from the end of 1970 through the end of 2007. The strengths of these data come from the fact that neither childhood nor adult characteristics are self reported and thus are not subject to recall bias, misreporting and no loss to follow-up after age 35. In addition, the study population includes several families with at least two children enabling us to control for unobserved family characteristics. We documented significant associations between early life social and family conditions on all-cause mortality and cause-specific mortality, with protective effects of higher childhood socio-demographic characteristics varying between 10% and 30%. These associations were mostly mediated through adult educational attainment and occupation, suggesting that the indirect effects of childhood conditions were more important than their direct effects. We further found that adult socioeconomic status was a significant predictor of mortality. The associations between adult characteristics and mortality were robust to controls for observed and unobserved childhood characteristics. The results imply that long-term adverse health consequences of disadvantaged early life social circumstances may be mitigated by investments in educational and employment opportunities in early adulthood.

Childhood socioeconomic status, telomere length, and susceptibility to upper respiratory infection

Low socioeconomic status (SES) during childhood and adolescence has been found to predict greater susceptibility to common cold viruses in adults. Here, we test whether low childhood SES is associated with shorter leukocyte telomere length in adulthood, and whether telomere length mediates the association between childhood SES and susceptibility to acute upper respiratory disease in adulthood. At baseline, 196 healthy volunteers reported whether they currently owned their home and, for each year of their childhood, whether their parents owned the family home. Volunteers also had blood drawn for assessment of specific antibody to the challenge virus, and for CD8+ CD28- T-lymphocyte telomere length (in a subset, n=135). They were subsequently quarantined in a hotel, exposed to a virus (rhinovirus [RV] 39) that causes a common cold and followed for infection and illness (clinical cold) over five post-exposure days. Lower childhood SES as measured by fewer years of parental home ownership was associated with shorter adult CD8+ CD28- telomere length and with an increased probability of developing infection and clinical illness when exposed to a common cold virus in adulthood. These associations were independent of adult SES, age, sex, race, body mass, neuroticism, and childhood family characteristics. Associations with infections and colds were also independent of pre-challenge viral-specific antibody and season. Further analyses do not support mediating roles for smoking, alcohol consumption or physical activity but suggest that CD8+ CD28- cell telomere length may act as a partial mediator of the associations between childhood SES and infection and childhood SES and colds.