Socioeconomic inequalities in molecular risk for chronic diseases observed in young adulthood.

Many common chronic diseases of aging are negatively associated with socioeconomic status (SES). This study examines whether inequalities can already be observed in the molecular underpinnings of such diseases in the 30s, before many of them become prevalent. Data come from the National Longitudinal Study of Adolescent to Adult Health (Add Health), a large, nationally representative sample of US subjects who were followed for over two decades beginning in adolescence. We now have transcriptomic data (mRNA-seq) from a random subset of 4,543 of these young adults. SES in the household-of-origin and in young adulthood were examined as covariates of a priori-defined mRNA-based disease signatures and of specific gene transcripts identified de novo. An SES composite from young adulthood predicted many disease signatures, as did income and subjective status. Analyses highlighted SES-based inequalities in immune, inflammatory, ribosomal, and metabolic pathways, several of which play central roles in senescence. Many genes are also involved in transcription, translation, and diverse signaling mechanisms. Average causal-mediated effect models suggest that body mass index plays a key role in accounting for these relationships. Overall, the results reveal inequalities in molecular risk factors for chronic diseases often decades before diagnoses and suggest future directions for social signal transduction models that trace how social circumstances regulate the human genome.

Methodological Approaches to Structural Change: Epidemiology and the Case for Reparations.

Scholars, activists, and policymakers have long called for reparations - a process of repair and restitution for harm and injustices done - to descendants of enslaved Africans in the U.S. as a structural intervention to address historic and ongoing injustices. However, there has been very limited epidemiologic work examining reparations. We explore some of the epidemiologic benefits and challenges of using causal inference frameworks to model reparations as an example of a large-scale, structural intervention that pushes the limits of what is considered "well-defined" and may violate key identification assumptions. Finally, we weigh these methodological limitations with the utility of assessing public health implications of reparations policies and conclude by discussing implications for future epidemiologic research.

A critique and examination of the polysocial risk score approach: predicting cognition in the Health and Retirement Study.

Polysocial risk scores were recently proposed as a strategy for improving the clinical relevance of knowledge about social determinants of health. Our objective in this study was to assess whether the polysocial risk score model improves prediction of cognition and all-cause mortality in middle-aged and older adults beyond simpler models including a smaller set of key social determinants of health. We used a sample of 13 773 individuals aged ≥50 years at baseline from the 2006-2018 waves of the Health and Retirement Study, a US population-based longitudinal cohort study. Four linear mixed models were compared: 2 simple models including a priori-selected covariates and 2 polysocial risk score models which used least absolute shrinkage and selection operator (LASSO) regularization to select covariates among 9 or 21 candidate social predictors. All models included age. Predictive accuracy was assessed via R2 and root mean-squared prediction error (RMSPE) using training/test split validation and cross-validation. For predicting cognition, the simple model including age, race, sex, and education had an R2 value of 0.31 and an RMSPE of 0.880. Compared with this, the most complex polysocial risk score selected 12 predictors (R2 = 0.35 and RMSPE = 0.858; 2.2% improvement). For all-cause mortality, the simple model including age, race, sex, and education had an area under the receiver operating characteristic curve (AUROC) of 0.747, while the most complex polysocial risk score did not demonstrate improved performance (AUROC = 0.745). Models built on a smaller set of key social determinants performed comparably to models built on a more complex set of social "risk factors."

A Prospective Sociocentric Study of 2 Entire Traditional Korean Villages: The Korean Social Life, Health, and Aging Project (KSHAP).

The Korean Social Life, Health, and Aging Project (KSHAP) was a multidisciplinary prospective study conducted in South Korea that measured various health biomarkers from blood, hair, and brain magnetic resonance imaging, and we examined their associations with sociocentric (global) social network data of older adults in 2 entire villages (or cohorts). Cohort K included participants aged 60 years or older, and cohort L included participants aged 65 years or older. We performed a baseline survey involving 814 of the 860 individuals (94.7% response rate) in cohort K in 2012 and 947 of the 1,043 individuals (90.8% response rate) in cohort L in 2017. We gathered longitudinal data for 5 waves in cohort K from 2011 to 2019 and 2 waves in cohort L from 2017 to 2022. Here, we describe for the first time the follow-up design of the KSHAP, the changes in social networks, and various biomarkers over a number of years. The data for cohort K are publicly available via the Korean Social Science Data Archive as well as the project website, and the data for cohort L will be shared soon.

Critical Feminist Epidemiology in Action: Reflections from a Multidisciplinary Partnership Between Mujeres Unidas y Activas and Academic Researchers.

Critical feminist research addresses social inequities, encourages equitable partnerships between researchers and participants, and acknowledges that research can be inherently political. Building upon critical feminist research practices, community-based participatory research, and social and structural epidemiology, we propose the approach of critical feminist epidemiology. A critical feminist epidemiology approach can study community and population health inequities with an eye towards identifying interventions that reduce inequities, through research processes that center the lived experiences of people from minoritized genders. We describe how our interdisciplinary, community-led team used a critical feminist epidemiology approach for an applied public health research project. Mujeres Unidas y Activas, a community organizing non-profit led by and for Latina and Indigenous immigrant women, partnered with academic researchers to conduct community-led research around how their approach to building community power affected the health and wellbeing of organization members and their families. Critical feminist epidemiology is a promising approach for conducting research that is grounded in and relevant to the lives of women and gender expansive people. Building upon social epidemiology and community-based participatory research, critical feminist epidemiology can be a useful research approach to generate novel evidence to inform action towards health equity for communities and populations.

Venkatapuram Responds to "Positive epidemiology, revisited: The case for centering human rights and economic justice".

This commentary responds to the article by Qureishi et al. (Am J Epidemol. XXXX;XXX(XX):XXXX-XXXX)) that criticizes a new proposal for "positive epidemiology." They argue that positive epidemiology as it is being proposed and conducted ignores supra-individual social contextual factors that constrain wellbeing of some individuals more than others, and it could exacerbate inequalities if applied at a population level, among other harms. They offer an alternative approach to defining causal factors that are helpful for wellbeing, and seek to ground their view in human rights and economic justice frameworks. This commentary considers their criticisms of PE and suggests that their alternative as well as all research into positive health and wellbeing would benefit from drawing on the ongoing debates and works in health equity and justice philosophy. A coherent conception of health and wellbeing, the link between health/wellbeing and theories of justice, and the capabilities approach are discussed. The efforts at conducting epidemiology for the causes and distribution of good health and wellbeing grounded in justice is welcomed.

Improving spatial exposure data for everyone - lifecourse social context and ascertaining residential history.

Measuring age-specific, contextual exposures is crucial for lifecourse epidemiology research. Longitudinal residential data offers a "golden ticket" to cumulative exposure metrics and can enhance our understanding of health disparities. Residential history can be linked to myriad spatiotemporal databases to characterize environmental, socioeconomic, and policy contexts that a person experienced throughout life. However, obtaining accurate residential history is challenging in the United States due to the limitations of administrative registries and self-reports. Xu et al. (Am J Epidemiol. 2024; 193(2):348-359) detail an approach to linking residential history sourced from LexisNexis ® Accurint ® to a Wisconsin-based research cohort, offering insights into challenges with residential history collection. Researchers must analyze the magnitude of selection and misclassification biases inherent to ascertaining residential history from cohort data. A lifecourse framework can provide insights into why the frequency and distance of moves is patterned by age, birth cohort, racial/ethnic identity, socioeconomic status, and urbanicity. Historic and contemporary migration patterns of marginalized people seeking economic and political opportunities must guide interpretations of residential history data. We outline methodologic priorities for use of residential history in health disparities research, including contextualizing residential history data with determinants of residential moves, triangulating spatial exposure assessment methods, and transparently quantifying measurement error.

Estimating the causal effects of income on health: how researchers' definitions of "income" matter.

BACKGROUND: There is a well-established cross-sectional association between income and health, but estimates of the causal effects of income vary substantially. Different definitions of income may lead to substantially different empirical results, yet research is often framed as investigating "the effect of income" as if it were a single, easily definable construct. METHODS/RESULTS: The aim of this paper is to introduce a taxonomy for definitional and conceptual issues in studying individual- or household-level income for health research. We focus on (1) the definition of the income measure (earned and unearned; net, gross, and disposable; real and nominal; individual and household; relative and absolute income) and (2) the definition of the causal contrast (amount, functional form assumptions/transformations, direction, duration of change, and timing of exposure and follow-up). We illustrate the application of the taxonomy to four examples from the published literature. CONCLUSIONS: Quantified estimates of causal effects of income on health and wellbeing have crucial relevance for policymakers to anticipate the consequences of policies targeting the social determinants of health. However, much prior evidence has been limited by lack of clarity in distinguishing between different causal questions. The present framework can help researchers explicitly and precisely articulate income-related exposures and causal questions.

Risk factors of suicide in prisons: a comprehensive retrospective cohort study in France, 2017-2020.

PURPOSE: Suicide is a leading cause of death in prison and the suicide rates are several times higher in the prison population than in the general population in most countries. Of the studies that have investigated risk factors for suicide in prison, few have controlled for possible confounding factors. The aim of this study is to identify risk factors of suicide among people in French prisons, over a four-year period. METHODS: All incarcerations that occurred in France during 2017-2020 were eligible. Sociodemographic, criminal and prison characteristics were collected for each incarceration from data of the National Prison Service. Survival univariate and multivariate analyses were performed with a Cox regression model. RESULTS: 358,522 incarcerations were included, of which 449 ended in suicide during the follow-up. The median length of prison stay was 5.1 months. The median age at prison entry was 30 years and 95.8% of incarcerations involved men. The overall suicide rate was 173 [157-189] per 100,000 person-years. Factors associated with suicide in the multivariate model (p < 0.05) were the early stage of incarceration and in particular the first week (HR = 7.6 [5.4-10.8]), violent offences and in particular homicide (HR = 3.0 [2.1-4.2]), French (HR = 1.7 [1.2-2.4]) and other European nationalities (HR = 2.1 [1.4-3.3]), age above 40 (HR = 2.0 [1.5-2.6]), pre-trial incarceration (HR = 1.8 [1.4-2.3]), being separated (HR = 1.6 [1.1-2.3] and having a high school diploma (HR = 1.4 [1.0-1.8]). CONCLUSIONS: Factors associated with suicide in prison are complex and involve individuals' criminal history as well as conditions of incarceration. These characteristics may be relevant to focus suicide prevention efforts.

Poverty and birth cohort effects of experiencing the 2007-2009 Great Recession during adolescence on major depressive episodes and mental health treatment of young adults in the United States.

PURPOSE: Household economic adversity during adolescence is hypothesized to be a risk factor for poor mental health later in life. To test this hypothesis, we conducted a quasi-experimental analysis of an economic shock, the Great Recession of 2007-2009. We tested if going through adolescence during the Great Recession was associated with increased risk of major depressive episodes (MDE) and mental health treatment in young adulthood with potential moderation by household poverty to explore differences by economic adversity. METHODS: We analyzed data on young adults age 18-29 years from the 2005-2019 National Survey on Drug Use and Health (N = 145,394). We compared participants who were adolescents during the recession to those followed-up prior to the recession. Regression analysis tested effect modification by household poverty status. RESULTS: Adolescent exposure to the Great Recession was associated with higher likelihood of MDE during young adulthood (aOR = 1.30, 95% CI = 1.23, 1.37); there was no relationship with mental health treatment. Effects on MDE were stronger among those in households with higher incomes compared to those living in poverty. CONCLUSION: Findings support the hypothesis that exposure to the Great Recession during adolescence may have increased risk for MDE, but raise questions about whether the mechanism of this association is economic distress.

The Type I interferon antiviral gene program is impaired by lockdown and preserved by caregiving.

Previous research has linked perceived social isolation (loneliness) to reduced antiviral immunity, but the immunologic effects of the objective social isolation imposed by pandemic "shelter in place" (SIP) policies is unknown. We assessed the immunologic impact of SIP by relocating 21 adult male rhesus macaques from 2,000-m2 field cage communities of 70 to 132 other macaques to 2 wk of individual housing in indoor shelters. SIP was associated with 30% to 50% reductions in all circulating immune cell populations (lymphocytes, monocytes, and granulocytes), down-regulation of Type I interferon (IFN) antiviral gene expression, and a relative up-regulation of CD16- classical monocytes. These effects emerged within the first 48 h of SIP, persisted for at least 2 wk, and abated within 4 wk of return to social housing. A subsequent round of SIP in the presence of a novel juvenile macaque showed comparable reductions in circulating immune cell populations but reversal of Type I IFN reductions and classical monocyte increases observed during individual SIP. Analyses of lymph node tissues showed parallel up-regulation of Type I IFN genes and enhanced control of viral gene expression during juvenile-partnered SIP compared to isolated SIP. These results identify a significant adverse effect of SIP social isolation on antiviral immune regulation in both circulating immune cells and lymphoid tissues, and they suggest a potential behavioral strategy for ameliorating gene regulatory impacts (but not immune cell declines) by promoting prosocial engagement during SIP.

Race, community disadvantage, and cognitive decline: Findings from KHANDLE and STAR.

INTRODUCTION: Community disadvantage is associated with late-life cognition. Few studies examine its contribution to racial disparities in cognition/cognitive change. METHODS: Inverse probability weighted models estimated expected mean differences in cognition/cognitive change attributed to residing in less advantaged communities, defined as cohort top quintile of Area Deprivation Indices (ADI): childhood 66-100; adulthood ADI 5-99). Interactions by race tested. RESULTS: More Black participants resided in less advantaged communities. Semantic memory would be lower if all participants had resided in less advantaged childhood (b = -0.16, 95% confidence interval [CI] = -0.30, -0.03) or adulthood (b = -0.14, 95% CI = -0.22, -0.04) communities. Race interactions indicated that, among Black participants, less advantaged childhood communities were associated with higher verbal episodic memory (interaction p-value = 0.007) and less advantaged adulthood communities were associated with lower semantic memory (interaction p-value = 0.002). DISCUSSION: Examining racial differences in levels of community advantage and late-life cognitive decline is a critical step toward unpacking community effects on cognitive disparities.

Foreclosure, memory decline, and dementia probability: A longitudinal cohort study.

INTRODUCTION: Housing insecurity is rising among older adults; health researchers know little about how this may impact their cognitive health. We investigated links between foreclosure and older adults' memory and probability of dementia. METHODS: Using the Health and Retirement Study (2008 to 2018), we fit mixed models comparing the memory and dementia probability scores of 249 older adults who experienced foreclosure (treated) with 15,645 who did not. Baseline covariates included sociodemographics, health, and cognition. Models were stratified by age group. RESULTS: Foreclosure was associated with faster memory decline among middle-aged (50 to 64) older adults (-0.007 standard deviations/year, 95% confidence interval: -0.13, -0.001). Compared to average memory decline among middle-aged older adults who were stably housed, foreclosure equated to 3.7 additional years of aging over 10 years. Among those 65+, differences between those who were and were not foreclosed upon were short-lived and less clear, potentially driven by depletion-of-susceptibles bias. DISCUSSION: Foreclosure may endanger older adults' memory. HIGHLIGHTS: Housing instability is a key determinant of cognitive aging. We examined foreclosure and levels and changes in memory and dementia probability scores in the US older adult population. Foreclosure was associated with faster memory decline among middle-aged (50 to 64) older adults, equivalent to 3.7 additional years of cognitive aging over 10 years. Foreclosure yielded sharp memory declines and increases in dementia probability among older adults 65 and above. Foreclosure imposes a greater risk for older adults' cognitive decline.

Comprehensive and Integrated Services in Specialty Mental Health Treatment Facilities in the US: Differences by the Racial/Ethnic Composition of the Facility's Clientele, 2020.

The integration of multiple ancillary services into mental health treatment settings may improve outcomes, but there are no national studies addressing whether comprehensive services are distributed equitably. We investigated whether the availability of a wide range of service types differs based on the facility's racial/ethnic composition. We used the 2020 National Mental Health Services Survey to identify twelve services offered in outpatient mental health treatment facilities (N = 1,074 facilities). We used logistic regression to model each of the twelve services, predicted by the percentage of a facility's clientele that was White, Black, and Hispanic, adjusted for covariates. Facilities with the highest proportions of Black and Hispanic clientele demonstrated the lowest predicted probabilities of offering comprehensive and integrated services. Our findings offer context around upstream factors that may, in part, drive treatment disparities. We orient our findings around frameworks of structural racism and inequities in mental healthcare.

Social inequalities in health within the City of Milan (Lombardy Region, Northern Italy): An ecological assessment.

OBJECTIVES: to document existing geographical inequalities in health in the city of Milan (Lombardy Region, Northern Italy), examining the association between area socioeconomic disadvantage and health outcomes, with the aim to suggest policy action to tackle them. DESIGN: the analysis used an ecological framework; multiple health indicators were considered in the analysis; socioeconomic disadvantage was measured through indicators such as low education, unemployment, immigration status, and housing crowding. For each municipal statistical area, Bayesian Relative Risks of the outcomes (using the Besag-Yorkand-Mollié model) were plotted on the city map. To evaluate the association between social determinants and health outcomes, Spearman correlation coefficients were estimated. SETTING AND PARTICIPANTS: residents in the City of Milan aged between 30 and 75 years who were residing in Milan as of 01.01.2019, grouped in 88 statistical areas. MAIN OUTCOMES MEASURES: all-cause mortality, type-2 diabetes mellitus, hypertension, neoplasms, respiratory diseases, metabolic syndrome, antidepressants use, polypharmacy, and multimorbidity. RESULTS: the results consistently demonstrated a significant association between socioeconomic disadvantage and various health outcomes, with low education exhibiting the strongest correlations. Neoplasms displayed an inverse social gradient, while the relationship with antidepressant use varied. CONCLUSIONS: these findings provide valuable insights into the distribution of health inequalities in Milan and contribute to the existing literature on the social determinants of health. The study highlights the need for targeted interventions to address disparities and promote equitable health outcomes. The results can serve to inform the development of effective public health strategies and policies aimed at reducing health inequalities in the city.

Psychosocial aspects associated with self-reported oral health in Brazilians older adults.

OBJECTIVES: Oral health conditions can be determined by a series of factors that include psychosocial aspects. Therefore, this study aimed to investigate the association between psychosocial aspects and self-reported oral health in Brazilian older adults. METHODS: The Brazilian Longitudinal Study of Ageing (ELSI-Brazil) baseline data was analysed to develop this cross-sectional study. The outcome was self-reported oral health, and the psychosocial aspects included neighbourhood trust, life satisfaction and depressive symptoms. The associations were determined through Poisson regression models, controlling for socioeconomic, demographic and behavioural characteristics. RESULTS: A total of 9365 individuals with aged 50 years or over were included in this study. Individuals with good life satisfaction had 16% (PR: 0.84; 95% CI: 0.78-0.90) lower prevalence of having poor self-reported oral health. Individuals who have depressive symptoms and do not trust in the neighbourhood presented 17% (PR: 1.17; 95% CI: 1.09-1.25) and 12% (PR: 1.12; 95% CI: 1.04-1.21) higher prevalence of poor self-report oral health compared to those who did not show depressive symptoms and trust the neighbourhood. CONCLUSION: Our findings suggest that positive psychosocial aspects are moderately associated with better self-reported oral health. Therefore, we suggest that psychological health and social interaction should be present in public health policy actions.

Producing Change to Understand the Social Determinants of Health: The Promise of Experiments for Social Epidemiology.

In this commentary, invited for the 100th anniversary of the Journal, we discuss the addition of randomized experiments, along with natural experiments that emulate randomized trials using observational data, as designs in the social epidemiologist's toolbox. These approaches transform the way we define and ask questions about social exposures. They compel us to ask questions about how well-defined interventions change a social exposure that might lead to changes in health. As such, experiments are of unique public health and policy significance. We argue that they are a powerful approach to advance our understanding of how well-defined changes in social exposures impact health, and how credible social policy reforms may be instrumental to address health inequalities. We focus on two research designs. The first is a "pure" randomized controlled trial (RCT) in which the investigator defines and randomly assigns the intervention. The second is a natural experiment, which exploits the fact that policies or interventions in the real world often involve an element of random assignment, emulating an RCT. To give the reader our bottom line: While acknowledging their limits, we continue to be very excited about the promise of RCTs and natural experiments to advance social epidemiology.

The American Journal of Epidemiology and Social Epidemiology: Past and Future.

Historically, the American Journal of Epidemiology (AJE) has played an important role in the development of social epidemiology as a field. To mark the centennial of the Journal, we invited commentaries from 3 sets of authors in which we asked them to reflect on the role of the AJE in advancing our understanding of the social determinants of population health and health disparities. Drs. Lisa Berkman, Mauricio Avendano, and Emilie Courtin discuss the promises and pitfalls of using experimental data (from both randomized trials and natural policy experiments) to interrogate the causal connection between social determinants and population health outcomes. Drs. Julie Palmer, Yvette Crozier, and Lynn Rosenberg look back on the first 25 years of the Black Women's Health Study and the contributions of that study to our understanding of racial disparities in health. Drs. Luisa Borrell and Natalie Crawford review the AJE's contributions to the definition and use of race and ethnicity in epidemiologic research and make recommendations for strengthening diversity and inclusion in the profession. A common thread that emerges across the invited essays is the AJE's commitment to publishing articles that engage in critical self-reflection of the discipline.

Socioeconomic Inequalities and Molecular Risk for Aging in Young Adulthood.

Diverse manifestations of biological aging often reflect disparities in socioeconomic status (SES). In this paper, we examine associations between indicators of SES and an mRNA-based aging signature during young adulthood, before clinical indications of aging are common. We use data from wave V (2016-2018) of the National Longitudinal Study of Adolescent to Adult Health, a nationally representative study of adults aged 33-43 years, with transcriptomic data from a subset of 2,491 participants. Biological aging is measured using 1) a composite transcriptomic aging signature previously identified by Peters et al.'s out-of-sample meta-analysis (Nat Commun. 2015;6:8570) and 2) 9 subsets that represent functional pathways of coexpressed genes. SES refers to income, education, occupation, subjective social status, and a composite measure combining these 4 dimensions. We examine hypothesized mechanisms through which SES could affect aging: body mass index, smoking, health insurance status, difficulty paying bills, and psychosocial stress. We find that SES-especially the composite measure and income-is associated with transcriptomic aging and immune, mitochondrial, ribosomal, lysosomal, and proteomal pathways. Counterfactual mediational models suggest that the mediators partially account for these associations. The results thus reveal that numerous biological pathways associated with aging are already linked to SES in young adulthood.

Invited Commentary: Use of Epidemiologic Methods to Guide Comprehensive and Equitable Approaches to Policy.

Despite a dramatic reduction in the prevalence of commercial cigarette smoking in the United States, children are still commonly exposed to secondhand smoke (SHS), which is a cause of various pediatric health problems. Further, SHS exposure is patterned by race and class, exacting an inequitable toll on children from families with lesser social and economic advantage. In this issue of the Journal, Titus et al. (Am J Epidemiol. 2023;192(1):25-33) use natural experiment evaluation methods (difference-in-differences) to test whether the recently implemented US Department of Housing and Urban Development policy that forbade smoking in and around New York City Housing Authority buildings affected child respiratory health. The results from their work remind us that policies do not always impact outcomes as we might expect. Given that policy is one of the most potent tools for population health promotion, this work underlines the need for epidemiologists to engage in policy evaluation at all stages of the policy life cycle, in order to discover comprehensive approaches to policy development and implementation that prioritize equity and address structural racism.