Life Socioeconomic Position Research Articles

Early life socioeconomic position contributes to adult obesity independent of adult socioeconomic factors: Findings from The Sister Study cohort

Low socioeconomic position (SEP) has been associated with obesity within life stages; however, life course SEP may also alter downstream obesity risk. Research is needed to understand the impact of childhood SEP, independent of adult SEP, as well as SEP trajectories over the life course on adult obesity risk. We use data from the Sister Study, a prospective U.S. cohort of women aged 35–74 years (N = 50,884; enrollment: 2003–2009). Relative risks (RR) for adult obesity associated with childhood SEP (latent variable) and five latent life course SEP profiles were estimated in overall and race and ethnicity-stratified log binomial regression models. We estimated the direct effect of childhood SEP on adult obesity and mediation by adult SEP. Lower childhood SEP was associated with greater obesity risk (RR = 1.16, 95% CI: 1.15–1.17). In stratified models, RRs were elevated across groups though lower for Black and Hispanic/Latina participants, despite greater prevalence of obesity among Black participants. The direct effect of childhood SEP on adult obesity persisted in mediation models independent of adult SEP (RR = 1.10, 95% CI: 1.08–1.12) with adult SEP mediating approximately 40% of the total effect of childhood SEP on adult obesity. Furthermore, adult obesity risk was elevated for all life course SEP profiles compared to persistent high advantage. Life course SEP profiles indicating greater advantage in adulthood than childhood were not associated with reduced adult obesity risk among those experiencing less than high advantage in childhood. In conclusion, lower childhood SEP, independent of adult SEP, may be an important risk factor for adult obesity.

Early life factors and grip strength at older ages in two distinct populations in China and England

Abstract Background Early life factors are associated with poor physical and mental outcomes in late life. However how these are associated with grip strength, an objective measure of physical capacity and therefore morbidity and mortality in late life unclear. This analysis therefor explores the long-term effects of adverse childhood socioeconomic experiences and health on grip strength in late life, and how these are mediated by adult factors. Methods Data on early life events, health and socioeconomic factors and grip strength were collected from the China Health and Retirement Longitudinal Study (CHARLS) and English Longitudinal Study of Ageing (ELSA). Participants’ first entry into the survey from waves 1-3 in CHARLS and waves 1-9 in ELSA were included in the analysis. Sex stratified linear regression models were used to explore how early life factors affect grip strength. Childhood events included parental socioeconomic position and childhood health. Results 17,205 participants from CHARLS and 6,692 participants from ELSA were included in this analysis. Unlike ELSA, participants from CHARLS were younger, had lower education, low-income occupation and obese. Low parental education and poor child health perception were negatively associated with grip strength even after controlling for childhood and adult factors (adult socioeconomic position, adult body size, adult health and lifestyle) in men from both studies. While parental occupation was associated with grip strength for both males and females in both studies. Association of SEP and health in childhood with grip strengths at older ages were however explained by body size and adult health factors, and not adult SEP. Key messages • Early life socioeconomic position has a persistent effect of late physical health, even after considering adult health, socioeconomic position and lifestyle. • Early intervention in socioeconomic inequalities might improve health outcomes across the life course.

Social mobility across the lifecourse and DNA methylation age acceleration in adults in the UK

Disadvantaged socio-economic position (SEP) is associated with greater biological age, relative to chronological age, measured by DNA methylation (positive ‘age acceleration’, AA). Social mobility has been proposed to ameliorate health inequalities. This study aimed to understand the association of social mobility with positive AA. Diagonal reference modelling and ordinary least square regression techniques were applied to explore social mobility and four measures of age acceleration (first-generation: ‘Horvath’, ‘Hannum’ and second-generation: ‘Phenoage’, DunedinPoAm) in n = 3140 participants of the UK Household Longitudinal Study. Disadvantaged SEP in early life is associated with positive AA for three (Hannum, Phenoage and DunedinPoAm) of the four measures examined while the second generation biomarkers are associated with SEP in adulthood (p < 0.01). Social mobility was associated with AA measured with Hannum only such that compared to no mobility, upward mobility was associated with greater age independently of origin and destination SEP. Compared to continuously advantaged groups, downward mobility was associated with positive Phenoage (1.06y [− 0.03, 2.14]) and DunedinPoAm assessed AA (0.96y [0.24, 1.68]). For these two measures, upward mobility was associated with negative AA (Phenoage, − 0.65y [− 1.30, − 0.002]; DunedinPoAm, − 0.96y [− 1.47, − 0.46]) compared to continually disadvantaged groups. While we find some support for three models of lifecourse epidemiology with early life as a sensitive period, SEP across the lifecourse and social mobility for age acceleration measured with DNA methylation, our findings suggest that disadvantaged SEP across the lifecourse is most consistently associated with positive AA.

Socioeconomic position over the life-course and subjective social status in relation to nutritional status and mental health among Guatemalan adults

ObjectiveWe study how life course objective socioeconomic position (SEP) predicts subjective social status (SSS) and the extent to which SSS mediates the association of objective SEP with nutritional status and mental health outcomes. MethodsWe use data from participants of the INCAP Longitudinal Study 1969–2018 (n = 1258) from Guatemala. We use the MacArthur ladder for two measures of SSS - perceived community respect and perceived economic status. We estimate the association of SSS with health outcomes after adjusting for early life characteristics and life course objective SEP (wealth, schooling, employment) using linear regression. We use path analysis to study the extent of mediation by SSS on the health outcomes of body mass index (BMI; kg/m2), psychological distress (using the WHO Self-Reported Questionnaire; SRQ-20) and happiness, using the Subjective Happiness Scale (SHS). ResultsMedian participant rating was 5 [IQR: 3–8] for the perceived community respect and 3 [IQR: 1–5] for the perceived economic status, with no differences by sex. Objective SEP in early life and adulthood were predictive of both measures of SSS in middle adulthood as well as health outcomes (BMI, SRQ-20 and SHS). Perceived community respect (z-scores; 1 z = 3.1 units) was positively associated with happiness (0.13, 95 % CI: 0.07, 0.19). Perceived economic status (z-scores; 1 z = 2.3 units) was inversely associated with psychological distress (−0.28, 95 % CI: −0.47, −0.09). Neither measure of SSS was associated with BMI. Neither perceived community respect nor perceived economic status attenuated associations of objective SEP with health outcomes on inclusion as a mediator. ConclusionsSubjective social status was independently associated with happiness and psychological distress in middle adulthood after adjusting for objective SEP. Moreover, association of objective SEP with health was not mediated by SSS, suggesting potentially independent pathways.

The relationship of childhood adversity with diurnal cortisol patterns and C-reactive protein at 60–64 years of age in the 1946 National Survey of Health and Development

BackgroundEarly life adversity is increasingly prevalent and associated with greater morbidity and mortality. It is hypothesised that the link between psychosocial early life adversity and poor health in adulthood is due to abnormal hypothalamic-pituitary-adrenal (HPA) axis functioning (often measured as cortisol patterning) and inflammation (often measured via c-reactive protein (CRP)). This study aimed to investigate the relationship between early life psychosocial adversity and cortisol patterning and CRP at 60–64 years of age. MethodsThe MRC National Survey of Health and Development (NSHD) was used. The analytic “cortisol sample” included 843 individuals and the “CRP sample” included 1150 individuals. Data on adversity experienced between ages 0–15 years were utilised to compose a cumulative childhood psychosocial early life adversity (ELA) score (0, 1, 2, 3+). CRP and salivary cortisol (waking, 30 min after waking, and evening) were collected at 60–64 years. Associations between the psychosocial ELA score and cortisol outcomes (cortisol awakening response (CAR), diurnal slope (DS), and evening and morning cortisol) were assessed using general linear regression. Tobit regression was used to assess the association between psychosocial ELA score and CRP. Adjustments were made for age at follow-up, sex, childhood maternal education, childhood paternal social class, childhood housing tenure, and birth weight. After testing for sex by ELA score interactions, analyses were repeated stratified by sex for the CRP sample. ResultsIn fully adjusted models, individuals who experienced the highest level of childhood psychosocial adversity (3+) had a 24.63 (−41.49, −7.76) % lower waking cortisol and a 7.30 (1.49, 13.12) % lower decline in cortisol across the day compared to those with a psychosocial ELA score of zero. In females, the highest level of childhood psychosocial adversity, compared to the lowest, was associated with 32.61 (2.98, 62.25) % higher CRP at 60–64 years, which attenuated to 20.38% (−9.38, 50.14) upon adjustment for measures of early life socioeconomic position. Conversely, the association between childhood psychosocial adversity and CRP in males was null. ConclusionsOur results suggest that high-levels of psychosocial adversity in childhood might result in a lower morning cortisol and flatter DS in mid-to-late-adulthood. The finding that adversity was related to higher CRP in females but not males requires replication and further investigation.

International differences in interspousal health correlations

Using objective measures of lung function, we document strong positive associations in health within couples in all European countries but large and significant differences in this correlation within broad European regions, with Southern Europe having by far stronger correlations than elsewhere. We analyze potential explanations for such differences, investigating the role of measures capturing current and past health behaviors, early life circumstances of each spouse, and measures capturing assortative mating in multiple dimensions. We show that marital sorting patterns by dimensions of early life health and socioeconomic position, as well as by geographical subregion within countries, are key to understanding the empirical patterns observed.

Influence of childhood socioeconomic position and ability on mid-life cognitive function: evidence from three British birth cohorts

BackgroundChildhood socioeconomic position (SEP) is robustly associated with cognitive function later in life. However, it is unclear whether this reflects a direct relationship, or an indirect association via modifiable factors...

Metabolic profiles of socio-economic position: a multi-cohort analysis.

BackgroundLow socio-economic position (SEP) is a risk factor for multiple health outcomes, but its molecular imprints in the body remain unclear.MethodsWe examined SEP as a determinant of serum nuclear magnetic resonance metabolic profiles in ∼30 000 adults and 4000 children across 10 UK and Finnish cohort studies.ResultsIn risk-factor-adjusted analysis of 233 metabolic measures, low educational attainment was associated with 37 measures including higher levels of triglycerides in small high-density lipoproteins (HDL) and lower levels of docosahexaenoic acid (DHA), omega-3 fatty acids, apolipoprotein A1, large and very large HDL particles (including levels of their respective lipid constituents) and cholesterol measures across different density lipoproteins. Among adults whose father worked in manual occupations, associations with apolipoprotein A1, large and very large HDL particles and HDL-2 cholesterol remained after adjustment for SEP in later life. Among manual workers, levels of glutamine were higher compared with non-manual workers. All three indicators of low SEP were associated with lower DHA, omega-3 fatty acids and HDL diameter. At all ages, children of manual workers had lower levels of DHA as a proportion of total fatty acids.ConclusionsOur work indicates that social and economic factors have a measurable impact on human physiology. Lower SEP was independently associated with a generally unfavourable metabolic profile, consistent across ages and cohorts. The metabolites we found to be associated with SEP, including DHA, are known to predict cardiovascular disease and cognitive decline in later life and may contribute to health inequalities.

Socioeconomic inequalities in blood pressure: co-ordinated analysis of 147,775 participants from repeated birth cohort and cross-sectional datasets, 1989 to 2016

BackgroundHigh blood pressure (BP) is a key modifiable determinant of cardiovascular disease and a likely determinant of other adverse health outcomes. While socioeconomic inequalities in BP are well documented, it remains unclear (1) how these inequalities have changed across time, given improvements over time in the detection and treatment of high BP (hypertension); (2) whether BP inequalities are present below and above hypertension treatment thresholds; and (3) whether socioeconomic position (SEP) across life has cumulative effects on BP. We sought to address these gaps using evidence from two complementary sources: birth cohort and repeated cross-sectional datasets.MethodsWe used three British birth cohort studies—born in 1946, 1958, and 1970—with BP measured at 43–46 years (in 1989, 2003, and 2016), and 21 repeated cross-sectional datasets—the Health Survey for England (HSE), with BP measured among adults aged ≥ 25 years (1994–2016). Adult education attainment was used as an indicator of SEP in both datasets; childhood father’s social class was used as an alternative indicator of (early life) SEP in cohorts. Adjusting for the expected average effects of antihypertensive medication use, we used linear regression to quantify SEP differences in mean systolic BP (SBP), and quantile regression to investigate whether inequalities differed across SBP distributions—below and above hypertension treatment thresholds.ResultsIn both datasets, lower educational attainment was associated with higher SBP, with similar absolute magnitudes of inequality across the studied period. Differences in SBP by education (Slope Index of Inequality) based on HSE data were 3.0 mmHg (95% CI 1.8, 4.2) in 1994 and 4.3 mmHg (2.3, 6.3) in 2016. Findings were similar for diastolic BP (DBP) and survey-defined hypertension. Inequalities were found across the SBP distribution in both datasets—below and above the hypertension threshold—yet were larger at the upper tail; in HSE, median SBP differences were 2.8 mmHg (1.7, 3.9) yet 5.6 mmHg (4.9, 6.4) at the 90th quantile. Adjustment for antihypertensive medication use had little impact on the magnitude of inequalities; in contrast, associations were largely attenuated after adjustment for body mass index. Finally, cohort data suggested that disadvantage in early and adult life had cumulative independent associations with BP: cohort-pooled differences in SBP were 5.0 mmHg (3.8, 6.1) in a score combining early life social class and own education, yet were 3.4 mmHg (2.4, 4.4) for education alone.ConclusionSocioeconomic inequalities in BP have persisted from 1989 to 2016 in Britain/England, despite improved detection and treatment of high BP. To achieve future reductions in BP inequalities, policies addressing the wider structural determinants of high BP levels are likely required, particularly those curtailing the obesogenic environment—targeting detection and treatment alone is unlikely to be sufficient.

Measuring Child Socio-Economic Position in Birth Cohort Research: The Development of a Novel Standardized Household Income Indicator.

The assessment of early life socioeconomic position (SEP) is essential to the tackling of social inequalities in health. Although different indicators capture different SEP dimensions, maternal education is often used as the only indicator in birth cohort research, especially in multi-cohort analyses. Household income, as a direct measure of material resources, is one of the most important indicators, but one that is underused because it is difficult to measure through questionnaires. We propose a method to construct a standardized, cross-cohort comparable income indicator, the “Equivalized Household Income Indicator (EHII)”, which measures the equivalized disposable household income, using external data from the pan-European Union Statistics on Income and Living Conditions (EUSILC) surveys, and data from the cohorts. We apply this method to four studies, Piccolipiù and NINFEA from Italy and ELFE and EDEN from France, comparing the distribution of EHII with other SEP-related variables available in the cohorts, and estimating the association between EHII and child body mass index (BMI). We found that basic parental and household characteristics may be used, with a fairly good performance, to predict the household income. We observed a strong correlation between EHII and both the self-reported income, whenever available, and other individual socioeconomic-related variables, and an inverse association with child BMI. EHII could contribute to improving research on social inequalities in health, in particular in the context of European birth cohort collaborative studies.

Early life socioeconomic position and adult systemic inflammation: the role of gene regulation

Abstract Background Adverse socioeconomic conditions in childhood affect systemic low-grade inflammation in adulthood. Studies in animals and humans suggest that socioeconomic conditions get under the skin from early life thus contributing to shape pro-inflammatory phenotypes. Although the existence of socioeconomic differences in gene regulation of the immune function have been described previously, no study has so far assessed the extent to which these differences actually explain socioeconomic variations in inflammatory markers. Methods First, we ran 2-sample Mendelian Randomization (MR) methods to identify putative genes whose expression drives C-reactive protein (CRP) levels in blood. We used two databases with summary statistics of associations between single nucleotide polymorphisms and gene expression (eQTLGen, N = 31,486 individuals) and CRP (CHARGE, N = 148,164 individuals) in blood. We tested 10,701 genes and retained those with FDR&amp;lt;0.05. Second, we used individual-participant data from a Swiss population-based study (SKIPOGH, N = 723) to estimate the proportion of the effect of paternal occupational position (SEP) on low-grade inflammation in adulthood (CRP&amp;gt;3mg/L) mediated by the selected genes. We estimated odds ratios and mediated proportions through counterfactual-based mediation models. Results We identified 426 genes driving CRP levels (robust to unmeasured confounding thanks to MR). They jointly mediated the effect of low father’s occupation on inflammation in adulthood for a proportion up to about 70% [95% confidence intervals (CI) 11-90%] and with an odds ratio of 1.53 [95% CI 1.05-2.15] compared to individuals with high paternal SEP. Analysis of the effects of life-course SEP trajectories (upward, downward and stable low from paternal to adult SEP) on gene regulation revealed trajectory dependent effects. Conclusions We suggest that adverse childhood SEP affects systemic inflammation in adulthood through a long-lasting effect on gene regulation.

Lifecourse epidemiology matures: Commentary on Zhang et al. “Early-life socioeconomic status, adolescent cognitive ability, and cognition in late midlife”

The effect of education on late life cognition has attracted substantial attention in lifecourse epidemiology, in part because of its relevance for understanding the effect of education on dementia. Although numerous studies document an association between education and later life cognition, these studies are potentially confounded by early life socioeconomic position and cognition. Good measures of these early life constructs are rarely available in data sets assessing cognition in late life. A further body of evidence has taken advantage of compulsory schooling law (CSL) instrumental variables (IV), although these estimates have been criticized based on questions about the validity of CSL IVs. In this issue of the Journal, Zhang et al. took advantage of the Wisconsin Longitudinal Study to control for both prospectively measured adolescent IQ and early life socioeconomic status in an analysis evaluating the effect of education on cognitive scores in late middle age (Zhang et al., 2019; IN THIS ISSUE). Their results indicate a moderate effect of each additional year of education on later life cognition, of approximately 0.1–0.15 standard deviations per year of schooling. These estimates are remarkably aligned with findings from prior observational designs and from the CSL IV studies. Although criticisms of any individual study are plausible, this new study complements the body of prior evidence to provide compelling evidence for the benefits of education on late life cognition.

Socio-economic position across the lifecourse and risk of breast cancer: findings from EPIC-Italy

Abstract Backgrounds Socio-economic position (SEP) is linked to many health outcomes but the link between SEP and breast cancer (BC) is complex. This study explores the relationship between SEP from early life and future risk of BC. Methods We used data from the Italian component of the European prospective investigation into cancer and nutrition: EPIC-Italy (up to 26,391 women). Cox proportional hazard models were used to estimate the association between measures of life course SEP (father’s occupation, educational level, highest household occupation) with risk of BC, adjusting for health behaviours (smoking, alcohol, physical activity, Mediterranean diet), height, weight and reproductive factors (postmenopausal status, age at first full term pregnancy). To mimic life course experiences, we analysed the relationship between father’s occupation and risk of BC, sequentially adjusting for SEP in young adulthood and adulthood, as well as the impact of social mobility. Results We observed a significant association between father’s occupation and risk of BC, where participant with low SEP had lower risk to develop BC (HR[95%CI] = 0.88[0.78; 0.99]). This association was borderline significant when we analysed educational level and highest household occupation. These associations were only slightly modified after adjustment for health behaviours, height and weight but more strongly affected by reproductive factors. However, the association between father’s occupation and BC remained borderline significant in the fully adjusted model (HR[95%CI] = 0.91[0.80; 1.03]). Stable low trajectory showed a lower risk of BC (HR[95%CI] = 0.82[0.71; 0.96]) slightly attenuated after adjusted for reproductive factors (HR[95%CI] = 0.88 [0.75; 1.03]). Conclusions Our findings suggest that low early-life SEP and stable low trajectory are associated with a lower risk of BC, which is partly explained by reproductive factors. Key messages Low early life socioeconomic position and stable low trajectory are associated with a lower risk of BC. Reproductive factors, especially age at the first full term pregnancy, explain part of these associations.

Early socioeconomic circumstances and cardiometabolic health in 10-year-old children

Abstract Background Social adversity is thought to become biologically embedded during sensitive periods of development, setting children on a trajectory of increased risk for later chronic diseases. Thus, social differences are expected to be expressed as biological alterations and might have their origins in early life. Therefore, we aim to estimate the association between early socioeconomic position (SEP) and cardiometabolic health during childhood. Methods Data from 2962 participants in the population-based birth cohort Generation XXI, from Porto, Portugal, was collected following standardized procedures at all study waves. Early SEP definition included household income, parental education and occupation at child’s birth. Cardiometabolic health was characterized at the age of 7 and 10, considering the triglycerides, cholesterol, fasting glucose, body mass index, systolic and diastolic blood pressure. Logistic regression was used to estimate the association between early SEP and a favorable cardiometabolic health profile. Results A favorable cardiometabolic profile was observed in almost half of participants at both ages, particularly among high SEP children who remain more frequently without alterations. For girls, higher paternal education at 7 years (OR:1.49;95%CI:1.03-2.15) and higher SEP at 10 were associated with better cardiometabolic health profile. In boys, a better cardiometabolic health profile was observed with increasing levels in maternal and paternal education and occupation, but at the age of 10, social differences were more evident according to parental education. Conclusions We provide evidence that children from more advantaged SEP at birth have an increased likelihood of presenting better cardiometabolic health at early ages. Social differences in cardiometabolic health biomarkers are already found in childhood, suggesting that the short-term impact of early life SEP on the physiology dysregulation takes place already in the first decade of life. Key messages Social differences in cardiometabolic health are already established in the first decade of life, with children from higher SEP presenting a better cardiometabolic health. Cardiovascular events are not expected to develop during childhood, however the underlying atherosclerotic process might already be in course as social differences appear to widen with age.

The effect of mid-life insulin resistance and type 2 diabetes on older-age cognitive state: the explanatory role of early-life advantage

Aims/hypothesisType 2 diabetes, hyperglycaemia and insulin resistance are associated with cognitive impairment and dementia, but causal inference studies using Mendelian randomisation do not confirm this. We hypothesised that early-life cognition and social/educational advantage may confound the relationship.MethodsFrom the population-based British 1946 birth cohort, a maximum number of 1780 participants had metabolic variables (type 2 diabetes, insulin resistance [HOMA2-IR] and HbA1c) assessed at age 60–64 years, and cognitive state (Addenbrooke’s Cognitive Examination III [ACE-III]) and verbal memory assessed at age 69 years. Earlier-life measures included socioeconomic position (SEP), cognition at age 8 years and educational attainment. Polygenic risk scores (PRSs) for type 2 diabetes were calculated. We first used a PRS approach with multivariable linear regression to estimate associations between PRSs and metabolic traits and later-life cognitive state. Second, using a path model approach, we estimated the interrelationships between earlier-life measures, features of mid-life type 2 diabetes and cognitive state at age 69 years. All models were adjusted for sex.ResultsThe externally weighted PRS for type 2 diabetes was associated with mid-life metabolic traits (e.g. HOMA2-IR β = 0.08 [95% CI 0.02, 0.16]), but not with ACE-III (β = 0.04 [−0.02, 0.90]) or other cognitive outcomes. While there was an association between HOMA2-IR and subsequent ACE-III (β = −0.09 [−0.15, −0.03]), path modelling showed no direct effect (β = −0.01 [−0.06, 0.03]) after accounting for the association between childhood SEP and education with HOMA2-IR. The same pattern was observed for later-life verbal memory.Conclusions/interpretationAssociations between type 2 diabetes and mid-life metabolic traits with subsequent cognitive state do not appear causal, and instead they may be explained by SEP in early life, childhood cognition and educational attainment. Therefore, glucose-lowering medication may be unlikely to combat cognitive impairment in older age.

Early life socioeconomic position and mortality from cardiovascular diseases: an application of causal mediation analysis in the Stockholm Public Health Cohort

ObjectiveWe aimed to quantify the mediating impact of adult social and behavioural mechanisms in the association between childhood socioeconomic position (SEP) and cardiovascular disease (CVD) mortality by employing a weighting...

Socioeconomic position during pregnancy and DNA methylation signatures at three stages across early life: epigenome-wide association studies in the ALSPAC birth cohort.

BackgroundSocioeconomic experiences are recognized determinants of health, and recent work has shown that social disadvantages in early life may induce sustained biological changes at molecular level that are detectable later in life. However, the dynamics and persistence of biological embedding of socioeconomic position (SEP) remains vastly unexplored.MethodsUsing the data from the ALSPAC birth cohort, we performed epigenome-wide association studies of DNA methylation changes at three life stages (birth, n = 914; childhood at mean age 7.5 years, n = 973; and adolescence at mean age 15.5 years, n = 974), measured using the Illumina HumanMethylation450 Beadchip, in relation to pregnancy SEP indicators (maternal and paternal education and occupation).ResultsAcross the four early life SEP metrics investigated, only maternal education was associated with methylation levels at birth, and four CpGs mapped to SULF1, GLB1L2 and RPUSD1 genes were identified [false discovery rate (FDR)-corrected P-value <0.05]. No epigenetic signature was found associated with maternal education in child samples, but methylation levels at 20 CpG loci were found significantly associated with maternal education in adolescence. Although no overlap was found between the differentially methylated CpG sites at different ages, we identified two CpG sites at birth and during adolescence which are 219 bp apart in the SULF1 gene that encodes an heparan sulphatase involved in modulation of signalling pathways. Using data from an independent birth cohort, the ENVIRONAGE cohort, we were not able to replicate these findings.ConclusionsTaken together, our results suggest that parental SEP, and particularly maternal education, may influence the offspring’s methylome at birth and adolescence.

Associations between body size, nutrition and socioeconomic position in early life and the epigenome: A systematic review.

BackgroundBody size, nutrition and socioeconomic position (SEP) in early life have been associated with a wide range of long-term health effects. Epigenetics is one possible mechanism through which these early life exposures can impact later life health. We conducted a systematic review examining the observational evidence for the impact of body size, nutrition and SEP in early life on the epigenome in humans.MethodsThis systematic review is registered with the PROSPERO database (registration number: CRD42016050193). Three datasets were simultaneously searched using Ovid and the resulting studies were evaluated by at least two independent reviewers. Studies measuring epigenetic markers either at the same time as, or after, the early life exposure and have a measure of body size, nutrition or SEP in early life (up to 12 years), written in English and from a community-dwelling participants were included.ResultsWe identified 90 eligible studies. Seventeen of these papers examined more than one early life exposure of interest. Fifty six papers examined body size, 37 nutrition and 17 SEP. All of the included papers examined DNA methylation (DNAm) as the epigenetic marker. Overall there was no strong evidence for a consistent association between these early life variables in DNAm which may be due to the heterogeneous study designs, data collection methods and statistical analyses.ConclusionsDespite these inconclusive results, the hypothesis that the early life environment can impact DNAm, potentially persisting into adult life, was supported by some studies and warrants further investigation. We provide recommendations for future studies.

The association of early life socioeconomic position on breast cancer incidence and mortality: a systematic review.

We conducted a systematic review of the literature relating early life socioeconomic position (SEP) to breast cancer incidence and mortality from a critical period and life-course trajectory perspective. PubMed, EMBASE and Web of Science were searched to identify cohort studies that evaluated the impact of early life SEP indicators on the incidence and/or mortality from breast cancer in adulthood. Nine distinct studies evaluated the relationship between early life SEP and breast cancer between 1990 and 2016. Five reports assessed breast cancer incidence and five assessed breast cancer mortality as outcomes; one study assessed both incidence and mortality. While lower early life SEP was associated with reduced breast cancer incidence and increased breast cancer mortality in the US, studies conducted in Europe were unable to establish a consistent association. We found moderate support for the association between early life SEP and incidence and mortality from breast cancer. The impact of early life SEP on breast cancer incidence and mortality appeared to vary between countries. We urge further investigation of the role of lifelong SEP trajectories in breast cancer outcomes.

Early life socioeconomic position and deaths from cardiovascular diseases: examining the mechanisms

Early life socioeconomic position and deaths from cardiovascular diseases: examining the mechanisms