The effect of smoking initiation in adolescence on the subsequent smoking trajectories of people who smoke, and the role of adverse childhood experiences: Results from the 1958 British cohort study.

OBJECTIVE: To examine the association between smoking initiation in adolescence and subsequent different smoking trajectories of people who smoke, and to examine the combined effect of adverse childhood experiences (ACEs) and smoking initiation in adolescence on smoking trajectories of people who smoke. DESIGN AND SAMPLE: Data are from 8757 individuals in Great Britain from the birth cohort National Child Development Study and who reported being smokers or former smokers by age 23. MEASUREMENTS: Smoking initiation in adolescence was measured at 16 y and smoking trajectories were derived from smoking variables from ages 23 to 55. We modelled the relationship between smoking initiation in adolescence with or without ACEs and smoking trajectories. RESULTS: Individuals who initiated smoking in adolescence were more likely to quit later than quitting in twenties (RRR quitting in thirties  = 3.43 [2.40; 4.89] p < .001; RRR quitting in forties  = 5.25 [3.38; 8.14] p < .001; RRR quitting in fifties  = 4.48 [2.95; 6.79] p < .001), to relapse (RRR Relapse  = 3.66 [2.82; 4.76] p < .001) and to be persistent smokers (RRR persistent  = 5.25 [3.81; 7.25] p < .001) compared to those who had initiated smoking in young adulthood. These effects were particularly pronounced in case of ACEs. CONCLUSION: Smoking prevention programs aimed at reducing smoking initiation should be promoted to adolescents to limit the burden of smoking, especially for people who have suffered adversity during childhood.

Educational patterning in biological health seven years apart: Findings from the Tromsø Study.

BACKGROUND: Social-to-biological processes is one set of mechanisms underlying the relationship between social position and health. However, very few studies have focused on the relationship between social factors and biology at multiple time points. This work investigates the relationship between education and the dynamic changes in a composite Biological Health Score (BHS) using two time points seven years apart in a Norwegian adult population. METHODS: We used data from individuals aged 30 years and above who participated in Tromsø6 (2007-2008) and Tromsø7 (2015-2016) (n = 8117). BHS was defined using ten biomarkers measured from blood samples and representing three physiological systems (cardiovascular, metabolic, inflammatory). The higher the BHS, the poorer the health status. FINDINGS: Linear regression models carried out on BHS revealed a strong educational gradient at two distinct time points but also over time. People with lower educational attainment were at higher risk of poor biological health at a given time point (ßlow education Tromsø6=0.30 [95 %-CI=0.18-0.43] and ßlow education Tromsø7=0.30 [95 %-CI=0.17-0.42]). They also presented higher longitudinal BHS compared to people with higher education (ßlow education = 0.89 [95 %-CI=0.56-1.23]). Certain biomarkers related to the cardiovascular system and the metabolic system were strongly socially distributed, even after adjustment for sex, age, health behaviours and body mass index. CONCLUSION: This longitudinal analysis highlights that participants with lower education had their biological health deteriorated to a greater extent over time compared to people with higher education. Our findings provide added evidence of the biological embodiment of social position, particularly with respect to dynamic aspects for which little evidence exists.

Assessing How Social Exposures Are Integrated in Exposome Research: A Scoping Review.

BACKGROUND: Exposome research aims to describe and understand the extent to which all the exposures in human environments may affect our health over the lifetime. However, the way in which humans interact with their environment is socially patterned. Failing to account for social factors in research exploring the exposome may underestimate the magnitude of the effect of exposures or mask inequalities in the distribution of both exposures and outcomes. OBJECTIVES: We aimed to describe the extent to which social factors appear in the exposome literature, the manner in which they are used in empirical analyses and statistical modeling, and the way in which they are considered in the overall scientific approach. METHODS: We conducted a scoping review of the literature using three databases (PubMed, Embase, and Web of Science) up to January 2022. We grouped studies based on the way in which the social variables were used in the analyses and quantified the type and frequency of social variables mentioned in the articles. We also qualitatively described the scientific approach used by authors to integrate social variables. RESULTS: We screened 1,001 records, and 73 studies were included in the analysis. Fifty-five (∼75%) used social variables as exposures or confounders or both, and a wide array of social variables were represented in the articles. Individual-level social variables were more often found, especially education and race/ethnicity, as well as neighborhood-level deprivation indices. Half of the studies used a hypothesis-free approach and the other half, a hypothesis-driven approach. However, in the latter group, of 35 studies, only 8 reported and discussed at least one possible social mechanism underlying the relationship observed between the social variable and the outcome. DISCUSSION: Social factors in exposome research should be considered in a more systematic way, considering their role in structuring both the specific external and the internal exposome. Doing so could help to understand the mechanisms of construction and, potentially, alleviate social inequalities in health and mitigate the emergence of new ones. https://doi.org/10.1289/EHP11015.

Health Impacts of the COVID-19 Lockdown Measure in a Low Socio-Economic Setting: A Cross-Sectional Study on Reunion Island.

In March 2020, the French government implemented nation-wide measures to reduce social contact and slow the progression of the emerging coronavirus responsible for COVID-19, the most significant being a complete home lockdown that lasted 8 weeks. Reunion Island is a French overseas department marked by large social inequalities. We draw the hypothesis that distancing and lockdown measures may have contributed to an increase in the social inequalities in health (SIH) on Reunion Island. The aim of our study was to describe the SIH during lockdown in the Reunionese population. We implemented a cross-sectional telephone survey conducted between 13 May and 22 July 2020, using a retrospective data collection on the lockdown period. A total of 892 adult participants (≥18 years) were recruited in the 114 large Reunionese neighborhoods using the quota method within the national "White Pages" telephone directory. Degraded psychological states, an increase in addictive behaviors, difficulties in accessing food, a decrease in physical activity, delayed medical appointments, violence against women, and health problems in children were driven by the socio-economic characteristics of the population, most often to the disadvantage of social groups exposed to poor living conditions. These results suggest that the COVID-19 lockdown contributed to an increase in SIH.

Avoiding overadjustment bias in social epidemiology through appropriate covariate selection: a primer.

Obtaining accurate estimates of the causal effects of socioeconomic position (SEP) on health is important for public health interventions. To do this, researchers must identify and adjust for all potential confounding variables, while avoiding inappropriate adjustment for mediator variables on a causal pathway between the exposure and outcome. Unfortunately, 'overadjustment bias' remains a common and under-recognized problem in social epidemiology. This paper offers an introduction on selecting appropriate variables for adjustment when examining effects of SEP on health, with a focus on overadjustment bias. We discuss the challenges of estimating different causal effects including overadjustment bias, provide guidance on overcoming them, and consider specific issues including the timing of variables across the life-course, mutual adjustment for socioeconomic indicators, and conducting systematic reviews. We recommend three key steps to select the most appropriate variables for adjustment. First, researchers should be clear about their research question and causal effect of interest. Second, using expert knowledge and theory, researchers should draw causal diagrams representing their assumptions about the interrelationships between their variables of interest. Third, based on their causal diagram(s) and causal effect(s) of interest, researchers should select the most appropriate set of variables, which maximizes adjustment for confounding while minimizing adjustment for mediators.

Considering sex and gender in Epidemiology: a challenge beyond terminology. From conceptual analysis to methodological strategies.

BACKGROUND: Epidemiologists need tools to measure effects of gender, a complex concept originating in the social sciences which is not easily operationalized in the discipline. Our aim is to clarify useful concepts, measures, paths, effects, and analytical strategies to explore mechanisms of health difference between men and women. METHODS: We reviewed concepts to clarify their definitions and limitations for their translation into usable measures in Epidemiology. Then we conducted methodological research using a causal framework to propose methodologically appropriate strategies for measuring sex and gender effects in health. RESULTS: (1) Concepts and measures. We define gender as a set of norms prescribed to individuals according to their attributed-at-birth sex. Gender pressure creates a systemic gap, at population level, in behaviors, activities, experiences, etc., between men and women. A pragmatic individual measure of gender would correspond to the level at which an individual complies with a set of elements constituting femininity or masculinity in a given population, place and time. (2) Main analytical strategy. Defining and measuring gender are not sufficient to distinguish the effects of sex and gender on a health outcome. We should also think in terms of mechanisms, i.e., how the variables are linked together, to define appropriate analytical strategies. A causal framework can help us to conceptualize "sex" as a "parent" of a gender or gendered variable. This implies that we cannot interpret sex effects as sexed mechanisms, and that we can explore gendered mechanisms of sex-differences by mediation analyses. (3) Alternative strategy. Gender could also be directly examined as a mechanism, rather than through a variable representing its realization in the individual, by approaching it as an interaction between sex and social environment. CONCLUSIONS: Both analytical strategies have limitations relative to the impossibility of reducing a complex concept to a single or a few measures, and of capturing the entire effect of the phenomenon of gender. However, these strategies could lead to more accurate analyses of the mechanisms underlying health differences between men and women.

Association of neighbourhood disadvantage and individual socioeconomic position with all-cause mortality: a longitudinal multicohort analysis.

BACKGROUND: Few studies have examined the interactions between individual socioeconomic position and neighbourhood deprivation and the findings so far are heterogeneous. Using a large sample of diverse cohorts, we investigated the interaction effect of neighbourhood socioeconomic deprivation and individual socioeconomic position, assessed using education, on mortality. METHODS: We did a longitudinal multicohort analysis that included six cohort studies participating in the European LIFEPATH consortium: the CoLaus (Lausanne, Switzerland), E3N (France), EPIC-Turin (Turin, Italy), EPIPorto (Porto, Portugal), Melbourne Collaborative Cohort Study (Melbourne, VIC, Australia), and Whitehall II (London, UK) cohorts. All participants with data on mortality, educational attainment, and neighbourhood deprivation were included in the present study. The data sources were the databases of each cohort study. Poisson regression was used to estimate the mortality rates and associations (relative risk, 95% CIs) with neighbourhood deprivation (Q1 being least deprived to Q5 being the most deprived). Baseline educational attainment was used as an indicator of individual socioeconomic position. Estimates were combined using pooled analysis and the relative excess risk due to the interaction was computed to identify additive interactions. FINDINGS: The cohorts comprised a total population of 168 801 individuals. The recruitment dates were 2003-06 for CoLaus, 1989-91 for E3N, 1992-98 for EPIC-Turin, 1999-2003 for EPIPorto, 1990-94 for MCCS, and 1991-94 for Whitehall II. We use baseline data only and mortality data obtained using record linkage. Age-adjusted mortality rates were higher among participants residing in more deprived neighbourhoods than those in the least deprived neighbourhoods (Q1 least deprived neighbourhoods, 369·7 per 100 000 person-years [95% CI 356·4-383·2] vs Q5-most deprived neighbourhoods 445·7 per 100 000 person-years [430·2-461·7]), but the magnitude of the association varied according to educational attainment (relative excess risk due to interaction=0·18, 95% CI 0·08-0·28). The relative risk for Q5 versus Q1 was 1·31 (1·23-1·40) among individuals with primary education or less, but less pronounced among those with secondary education (1·12; 1·04-1·21) and tertiary education (1·16; 1·07-1·27). Associations remained after adjustment for individual-level factors, such as smoking, physical activity, and alcohol intake, among others. INTERPRETATION: Our study suggests that the detrimental health effect of living in disadvantaged neighbourhoods is more pronounced among individuals with low education attainment, amplifying social inequalities in health. This finding is relevant to policies aimed at reducing health inequalities, suggesting that these issues should be addressed at both the individual level and the community level. FUNDING: The European Commission, European Regional Development Fund, the Portugese Foundation for Science and Technology.

Neighbourhood socio-economic vulnerability and access to COVID-19 healthcare during the first two waves of the pandemic in Geneva, Switzerland: A gender perspective.

Background: Neighbourhood socio-economic inequities have been shown to affect COVID-19 incidence and mortality, as well as access to tests. This article aimed to study how associations of inequities and COVID-19 outcomes varied between the first two pandemic waves from a gender perspective. Methods: We performed an ecological study based on the COVID-19 database of Geneva between Feb 26, 2020, and June 1, 2021. Outcomes were the number of tests per person, the incidence of COVID-19 cases, the incidence of COVID-19 deaths, the positivity rate, and the delay between symptoms and test. Outcomes were described by neighbourhood socio-economic levels and stratified by gender and epidemic waves (first wave, second wave), adjusting for the proportion of inhabitants older than 65 years. Findings: Low neighbourhood socio-economic levels were associated with a lower number of tests per person (incidence rate ratio [IRR] of 0.88, 0.85 and 0.83 for low, moderate, and highly vulnerable neighbourhood respectively), a higher incidence of COVID-19 cases and of COVID-19 deaths (IRR 2.3 for slightly vulnerable, 1.9 for highly vulnerable). The association between socio-economic inequities and incidence of COVID-19 deaths was mainly present during the first wave of the pandemic, and was stronger amongst women. The increase in COVID-19 cases amongst vulnerable populations appeared mainly during the second wave, and originated from a lower access to tests for men, and a higher number of COVID-19 cases for women. Interpretation: The COVID-19 pandemic affected people differently depending on their socio-economic level. Because of their employment and higher prevalence of COVID-19 risk factors, people living in neighbourhoods of lower socio-economic levels, especially women, were more exposed to COVID-19 consequences. Funding: This research was supported by the research project SELFISH, financed by the Swiss National Science Foundation, grant number 51NF40-160590 (LIVES centre international research project call).

Associations of adverse childhood experiences with smoking initiation in adolescence and persistence in adulthood, and the role of the childhood environment: Findings from the 1958 British birth cohort.

Adverse childhood experiences (ACEs) have been identified as a strong determinant of smoking. We aimed to examine the association between ACEs and early smoking initiation and subsequent persistence and the contribution of five pathways including family factors, parental involvement, material living conditions, social activities and conscientiousness. Data are from 7414 individuals born in 1958 in Great Britain included in the National Child Development Study. ACEs were measured at ages 7, 11, and 16. Smoking initiation was derived from smoking variables from ages 16 to 42 and persistent smoking was derived from smoking variables from ages 23 to 42. We modelled the relationship between ACEs and smoking, and further assessed the contribution of each pathway using multinomial logistic regressions. During childhood, 20.9% of respondents experienced one ACE and 6.4% two or more. Those who experienced ACEs had a higher risk of initiating smoking by age 16 and of persistent smoking (RRR initiation by 16y = 1.89 [1.62; 2.20] for one ACE; RRR initiation by 16y = 2.36 [1.81; 3.08] for two or more ACEs, and RRR persistent smoking = 2.07 [1.73; 2.47] for one ACE, RRR persistent smoking = 2.59 [1.92; 3.49] for two or more ACEs). The factors that contributed most to explaining these associations were parental smoking, sibling order and conscientiousness. ACEs remained associated with persistent smoking after further adjusting for young adulthood variables. Smoking prevention measures may need to be tailored when considering adolescents from communities where ACEs are more prevalent to curtail initiation, intensity and persistence. FUNDING: This work was supported by the Institut National du Cancer & the Institut de recherche en santé publique (grant agreement: No. [2019-204]).

Social protection expenditure on health in later life in 20 European countries: Spending more to reduce health inequalities.

BACKGROUND: This study aims to examine whether higher social protection expenditure reduces the negative association of life-course socioeconomic disadvantages with subjective and objective health status and trajectories in later life. METHODS: We used SHARE data from participants living in 20 European countries aged 50 to 96. Seven waves allowed to examine the trajectories of health inequalities in later life. We used linear mixed-effects models stratified by sex to examine the association between life-course socioeconomic disadvantage and subjective (self-rated health, SRH, N = 55,443) and objective (grip strength, N = 54,718) health. Cross-level interactions between net social protection expenditure as percentage of gross domestic product and life-course socioeconomic disadvantage tested for the moderating effect of social expenditures on the association of disadvantage with SRH and grip strength in later life. FINDINGS: Higher social protection expenditure reduced socioeconomic health inequalities in both men and women for grip strength, and in women but not men for SRH. For SRH, the health-inequality-reducing effect of social protection expenditure became weaker with increasing age. This was not observed in grip strength. Some separate expenditure functions (disability, family and children) were found to have inequality-widening effects in men's and women's SRH, which were either offset or overcompensated by the other functions. No inequality-widening effects were observed in grip strength. INTERPRETATION: Higher social spending reduces life-course socioeconomic inequalities in women's subjective health and in men's and women's objective health. However, some specific social protection policies may have the unintentional effect of increasing inequalities in people's evaluation of their own health.

Complex social gradient in life expectancy in Costa Rica: an ecological study with 24-Million person-years follow-up / Complejo gradiente socioeconómico en esperanza de vida en Costa Rica: un estudio ecológico con seguimiento de 24 millones de personas-año

ABSTRACT: The knowledge of Costa Rica's situation regarding the social gradient in mortality is still incomplete. National Electoral Rolls, which included all adult Costa Rican citizens were used. The event was death between 2010 and 2018. The exhaustive final sample included 2,747,616 people for 23,985,602 person-years of follow-up. An ecological study at the electoral district level was performed. A negative social gradient was observed in men and in women, in particular in urban area. A protective effect of rural areas compared to urban areas was revealed in men, but not in women. As a result, in men, the poorest districts of mixed/rural areas had similar life expectancy than the richest districts in urban areas. These results partially contradicted the international literature on socioeconomic inequalities. It demonstrates the importance of studying contexts other than high-income countries to better understand the social inequalities in health worldwide.

RESUMEN: El conocimiento sobre la distribución del gradiente social de la mortalidad en Costa Rica aún no ha sido totalmente comprendido y nuevos estudios pueden confirmar o refutar lo que anteriormente se ha observado. Se utilizaron las listas electorales nacionales, que incluían a todos los ciudadanos costarricenses adultos. El evento fue la muerte entre 2010 y 2018. Siendo la muestra exhaustiva final de 2.747.616 personas para 23.985.602 personas-año de seguimiento. Se realizó un estudio ecológico a nivel de distrito electoral, para caracterizar la situación socioeconómica de cada uno. Se observó un gradiente social negativo en hombres y mujeres, en particular en el área urbana. Se observó un efecto protector de las áreas rurales en comparación con las áreas urbanas en los hombres, pero no en las mujeres. Como resultado, en los hombres, los distritos más pobres de las áreas mixtas/rurales tenían una esperanza de vida similar a la de los distritos más ricos de las áreas urbanas. Estos resultados contradicen parcialmente la literatura internacional sobre las inequidades socioeconómicas en mortalidad. Demuestra la importancia de estudiar contextos distintos a los de los países de ingresos altos para comprender mejor las desigualdades sociales en salud en todo el mundo.

Framework for understanding health inequalities over the life course: the embodiment dynamic and biological mechanisms of exogenous and endogenous origin.

Understanding how structural, social and psychosocial factors come to affect our health resulting in health inequalities is more relevant now than ever as trends in mortality gaps between rich and poor appear to have widened over the past decades. To move beyond description, we need to hypothesise about how structural and social factors may cause health outcomes. In this paper, we examine the construction of health over the life course through the lens of influential theoretical work. Based on concepts developed by scholars from different disciplines, we propose a novel framework for research on social-to-biological processes which may be important contributors to health inequalities. We define two broad sets of mechanisms that may help understand how socially structured exposures become embodied: mechanisms of exogenous and endogenous origin. We describe the embodiment dynamic framework, its uses and how it may be combined with an intersectional approach to examine how intermeshed oppressions affect social exposures which may be expressed biologically. We explain the usefulness of this framework as a tool for carrying out research and providing scientific evidence to challenge genetic essentialism, often used to dismiss social inequalities in health.

Comparison of smoking reduction with improvement of social conditions in early life: simulation in a British cohort.

BACKGROUND: Health care evaluation models can be useful to assign different levels of priority to interventions or policies targeting different age groups or different determinants of health. We aimed to assess early mortality in counterfactual scenarios implying reduced adverse childhood experience (ACE) and/or improved educational attainment (childhood and early life characteristics), compared with a counterfactual scenario implying reduced smoking in adulthood. METHODS: We used data from the 1958 National Child Development Study British birth cohort, which initially included 18 558 subjects. Applying a potential outcome approach, scenarios were simulated to estimate the expected mortality between ages 16 and 55 under a counterfactual decrease by half of the observed level of exposure to (i) ACE, (ii) low educational attainment (at age 22), (iii) ACE and low educational attainment (a combined exposure) and (iv) smoking at age 33. Estimations were obtained using g-computation, separately for men and women. Analyses were further stratified according to the parental level of education, to assess social inequalities. RESULTS: The study population included 12 164 members. The estimated decrease in mortality in the counterfactual scenarios with reduced ACE and improved educational attainment was close to the decreased mortality in the counterfactual scenario with reduced smoking, showing a relative difference in mortality of respectively -7.2% [95% CI (confidence interval) = (-12.2% to 1.2%)] versus -7.0% (-13.1% to +1.2%) for women, and -9.9% (-15.6% to -6.2%) versus -12.3% (-17.0% to -5.9%) for men. CONCLUSIONS: Our results highlight the potential value of targeting early social characteristics such as ACE and education, compared with well-recognized interventions on smoking.

A multi-omics approach to investigate the inflammatory response to life course socioeconomic position.

Aim: Inflammation represents a potential pathway through which socioeconomic position (SEP) is biologically embedded. Materials & methods: We analyzed inflammatory biomarkers in response to life course SEP by integrating multi-omics DNA-methylation, gene expression and protein level in 178 European Prospective Investigation into Cancer and Nutrition-Italy participants. Results & conclusion: We identified 61 potential cis acting CpG loci whose methylation levels were associated with gene expression at a Bonferroni correction. We examined the relationships between life course SEP and these 61 cis-acting regulatory methylation sites individually and jointly using several scores. Less-advantaged SEP participants exhibit, later in life, a lower inflammatory methylome score, suggesting an overall increased expression of the corresponding inflammatory genes or proteins, supporting the hypothesis that SEP impacts adult physiology through inflammation.

Special Report: The Biology of Inequalities in Health: The Lifepath Consortium.

Funded by the European Commission Horizon 2020 programme, the Lifepath research consortium aimed to investigate the effects of socioeconomic inequalities on the biology of healthy aging. The main research questions included the impact of inequalities on health, the role of behavioral and other risk factors, the underlying biological mechanisms, the efficacy of selected policies, and the general implications of our findings for theories and policies. The project adopted a life-course and comparative approach, considering lifetime effects from childhood and adulthood, and pooled data on up to 1.7 million participants of longitudinal cohort studies from Europe, USA, and Australia. These data showed that socioeconomic circumstances predicted mortality and functional decline as strongly as established risk factors currently targeted by global prevention programmes. Analyses also looked at socioeconomically patterned biological markers, allostatic load, and DNA methylation using richly phenotyped cohorts, unraveling their association with aging processes across the life-course. Lifepath studies suggest that socioeconomic circumstances are embedded in our biology from the outset-i.e., disadvantage influences biological systems from molecules to organs. Our findings have important implications for policy, suggesting that (a) intervening on unfavorable socioeconomic conditions is complementary and as important as targeting well-known risk factors, such as tobacco and alcohol consumption, low fruit and vegetable intake, obesity and a sedentary lifestyle, and that (b) effects of preventive interventions in early life integrate interventions in adulthood. The report has an executive summary that refers to the different sections of the main paper.

Do Welfare Regimes Moderate Cumulative Dis/advantages Over the Life Course? Cross-National Evidence from Longitudinal SHARE Data.

OBJECTIVES: This study aimed to examine the cumulative disadvantage of different forms of childhood misfortune and adult-life socioeconomic conditions (SEC) with regard to trajectories and levels of self-rated health in old age and whether these associations differed between welfare regimes (Scandinavian, Bismarckian, Southern European, and Eastern European). METHOD: The study included 24,004 respondents aged 50-96 from the longitudinal SHARE survey. Childhood misfortune included childhood SEC, adverse childhood experiences, and adverse childhood health experiences. Adult-life SEC consisted of education, main occupational position, and financial strain. We analyzed associations with poor self-rated health using confounder-adjusted mixed-effects logistic regression models for the complete sample and stratified by welfare regime. RESULTS: Disadvantaged respondents in terms of childhood misfortune and adult-life SEC had a higher risk of poor self-rated health at age 50. However, differences narrowed with aging between adverse-childhood-health-experiences categories (driven by Southern and Eastern European welfare regimes), categories of education (driven by Bismarckian welfare regime), and main occupational position (driven by Scandinavian welfare regime). DISCUSSION: Our research did not find evidence of cumulative disadvantage with aging in the studied life-course characteristics and age range. Instead, trajectories showed narrowing differences with differing patterns across welfare regimes.

Health inequalities: Embodied evidence across biological layers.

RATIONALE: Socioeconomic disparities have been documented in major non-communicable diseases and in their risk factors, such as obesity, hypertension, diabetes, smoking, physical inactivity, unhealthful diet and heavy drinking. However, a key research question has remained unanswered: is there a separate biological embodiment of socio-economic conditions underlying health disparities, additional and independent of those risk factors? As lifelong socioeconomic circumstances cannot be randomised, one way forward is the examination of different biological layers of evidence, including molecular changes. METHOD: In this methodological paper we report the association of socio-economic disadvantage with (a) long-term health outcomes, before and after taking risk factors into account; (b) biological intermediaries that increase susceptibility to disease, such as childhood obesity; (c) intermediate circulating biomarkers and omic measurements (transcriptomics, DNA methylation, inflammatory proteins, allostatic load); and (d) immunity. In our Lifepath consortium, these analyses have been performed in several cohort studies, countries and contexts, and at different stages of the life course in up to 1.7 million subjects. The main goal is to test the assumption that each layer (death, functional outcomes, DNA, RNA, proteins, infections) is characterized by different types of bias and confounding, and that consistency across layers reinforces causality assessment. RESULTS: The findings show consistent associations of social disparities with unfavourable health outcomes spanning inflammatory biomarkers, DNA or RNA-based markers, infection, indicators of physical functioning and mortality. Although each of these associations has a different set of confounders, a dose-response relationship is nevertheless consistently observed, thus showing the power of our multi-layered approach. CONCLUSIONS: This new evidence supports biological embodiment of social disadvantage, in addition to the impact of known (mainly behavioural) risk factors for disease.

La santé des enfants en France : un enjeu négligé ?

INTRODUCTION: As part of the National Health Strategy, the High Council for Public Health (HCSP) was tasked with leading a reflection on a “comprehensive and concerted child health policy”. Policy-making requires relevant knowledge and statistical benchmarks. It therefore seemed useful to examine the French statistical system and active research topics. This assessment is expected to provide a current portrait of the priorities and implicit health choices for the children. It also aims to reveal insufficiently explored aspects of children’s health. METHODS: The inventory of this system was carried out on the basis of several methods, hearings, work of two documentalists, and analysis of the published and grey literature. RESULTS: The emphasis is on pathologies, medical prevention and behaviors conceived primarily as individual. The idea that the health of tomorrow’s adults is built up behind this apparent good health and its inequalities does not appear, or only marginally. The elements on affective, cognitive or relational development are not sufficiently analyzed, for lack of data. The living conditions of children, especially poverty and violence in all its forms, are not sufficiently considered as health issues. Research is developing today with a hospital-centric vision, without a real strategy of research on children’s health. DISCUSSION: Given the dispersion of data, publishing a summary report on children’s health on a regular basis is essential, as enriching the system with data on the environment, poverty and psychomotor, psychosocial and cognitive development. There is an urgent need to develop research on children’s health and to define a research strategy that does not exist today.