Harmonizing the assessment of allostatic load across cycles of the Canadian Health Measures Survey: Variable selection and calculation method.

Background: The availability of measures to operationalize allostatic load - the cumulative toll on the body of responding to stressor demands - in population health surveys may differ across years or surveys, hampering analyses on the entire sampled population. Here, impacts of variable selection and calculation method were evaluated to generate an allostatic load index applicable across all cycles of the Canadian Health Measures Survey (CHMS). Methods: Data from CHMS cycles 1 to 4 were used to compare allostatic load scores when replacing the most prevalent risk factor, waist-to-hip ratio - available in cycles 1 to 4 but not 5 and 6 - with body mass index (BMI), waist circumference, waist circumference within BMI groups (classified as normal, overweight, or obese), or waist-to-height ratio. Indexes were generated using clinical or sex-specific empirically defined risk thresholds and as count-based or continuous scores. Logistic regression models that included age and sex were used to relate each potential index to socioeconomic indicators (educational attainment, household income). Results: Of the variables assessed, waist-to-height ratio and waist circumference were closest to waist-to-hip ratio according to an individual's percentile ranking and in classifying "at risk" using either clinical or empirically defined cut-offs. Allostatic load profiles generated using waist-to-height ratios most closely resembled profiles constructed using waist-to-hip ratios. Sex-dependent associations with educational attainment and household income were maintained across constructs whether indexes were count-based or continuous. Interpretation: Allostatic load profiles and associations with socioeconomic indicators were robust to variable substitution and method of calculation, supporting the use of a harmonized index across survey cycles to assess the cumulative toll on health of stressor exposure.

The association between allostatic load and guaranteed annual income using the Canadian Longitudinal Study on Aging: A cross-sectional analysis of the benefits of guaranteed public pensions.

BACKGROUND: Old Age Security (OAS) represents an public policy through which income-related inequalities in health may be improved. The goal of this cross-sectional study was to investigate the health benefits of receiving OAS in financially insecure older Canadians. METHODS: Using data from the Canadian Longitudinal Study on Aging (CLSA) (n=15,691), ordered logistic regression was used to measure associations between financial insecurity and allostatic load. RESULTS: Receiving OAS as highest personal income source appeared to remove the health penalty of being financially insecure. While financial insecurity was associated with worse allostatic load in both males and females not receiving OAS, those receiving OAS as highest personal income source had better allostatic load compared to other financially insecure older adults (ORM: 0.398, 95 % CI: 0.227, 0.696; ORF: 0.677, 95 % CI: 0.483, 0.949). DISCUSSION: While longitudinal data would be needed to draw causal inferences, these results suggest OAS may play a role improving health outcomes and narrowing income-related health inequalities. Such findings may have important implications on older adults, other vulnerable populations, and future directions of Canadian health and public policy.

Education, Income, Wealth, and Discrimination in Black-White Allostatic Load Disparities.

INTRODUCTION: Allostatic load (AL) is a significant marker of aging, associated with disease and mortality. Research has elucidated the impact of education and income on AL. However, the roles of wealth and discrimination in contributing to AL and shaping AL disparities remain underexplored. This study aimed to investigate the association between wealth and AL, while also examining the independent contributions of education, income, wealth, and everyday discrimination in shaping AL disparities. METHODS: Using 2016 data from the nationally representative Health and Retirement Study (N=3,866), this study employed multilinear regression analysis to quantify the association between education and income, wealth (calculated as assets minus debts), and everyday discrimination with AL. Oaxaca-Blinder decomposition analysis was conducted to determine the proportion of AL disparities between Black and White participants attributed to education and income, wealth, and everyday discrimination. Analyses were performed in 2023. RESULTS: Having a college degree or more (b = -0.32; 95% CI: -0.46, -0.17), higher income (b = -0.06; 95% CI: -0.11, -0.01), and greater wealth (b = -0.11; 95% CI: -0.16, -0.07) were linked to reduced AL. Conversely, increased experiences of everyday discrimination were associated with heightened AL (b = 0.07; 95% CI: 0.01, 0.16). Collectively, differences in possessing a college degree or more, wealth, and exposure to discrimination accounted for about 18% of the observed Black-White AL disparities. CONCLUSIONS: Education, income, wealth, and experiences of discrimination may independently contribute to AL and partially explain Black-White disparities in AL. There is a need to elucidate the underlying mechanisms governing these relationships, particularly wealth, and extend the research to additional social determinants of racial health disparities.

Does it add up? Educational achievement mediates child maltreatment subtypes to allostatic load.

BACKGROUND: Childhood maltreatment (CM) has been linked to higher levels of allostatic load (AL) and educational achievement is a possible pathway and may differ across gender. It is also critical to determine if CM severity or specific subtypes of CM are more or less influential. OBJECTIVE: This study examined educational achievement as a mediator linking cumulative and individual types of CM to AL and examined gender as a moderator. PARTICIPANTS AND SETTING: Using two waves of data, 897 adults from the study Midlife in the United States were analyzed. METHODS: Multiple group structural equation models stratified across gender to test were used cumulative maltreatment and maltreatment subtypes to AL and test gender as a moderator. RESULTS: Overall CM was associated with educational achievement (ß = -0.12, p < .01) and AL (ß = 0.11, p < .05) and education was inversely associated with AL (ß = -0.17, p < .001) in men but not women. The subtypes model revealed that physical abuse predicted lower level of education achievement (ß = -0.20, p < .001) and among men. Educational achievement, in turn, was associated with lower levels of AL (ß = -0.02, p = .002). Educational achievement was a possible pathway linking physical abuse to AL (ß = 0.02, 95 % CI [0.001, 0.040]) among men but was non-significant in women. Gender did not moderate any of the pathways. CONCLUSIONS: Educational achievement is a potentially modifiable social determinant of health that can be a focus of prevention and intervention efforts among men who were maltreated, particularly for those who experienced physical abuse.

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.

The Implications of Racialized Economic Segregation and Allostatic Load on Mortality in Patients with Breast Cancer.

BACKGROUND: The objective of this study was to examine the association between racialized economic segregation, allostatic load (AL), and all-cause mortality in patients with breast cancer. PATIENTS AND METHODS: Women aged 18+ years with stage I-III breast cancer diagnosed between 01/01/2012 and 31/12/2020 were identified in the Ohio State University cancer registry. Racialized economic segregation was measured at the census tract level using the index of concentration at the extremes (ICE). AL was calculated with biomarkers from the cardiac, metabolic, immune, and renal systems. High AL was defined as AL greater than the median. Univariable and multivariable regression analyses using restricted cubic splines examined the association between racialized economic segregation, AL, and all-cause mortality. RESULTS: Among 4296 patients, patients residing in neighborhoods with the highest racialized economic segregation (Q1 versus Q4) were more likely to be Black (25% versus 2.1%, p < 0.001) and have triple-negative breast cancer (18.2% versus 11.6%, p < 0.001). High versus low racialized economic segregation was associated with high AL [adjusted odds ratio (aOR) 1.40, 95% confidence interval (CI) 1.21-1.61] and worse all-cause mortality [adjusted hazard ratio (aHR) 1.41, 95% CI 1.08-1.83]. In dose-response analyses, patients in lower segregated neighborhoods (relative to the 95th percentile) had lower odds of high AL, whereas patients in more segregated neighborhoods had a non-linear increase in the odds of high AL. DISCUSSION: Racialized economic segregation is associated with high AL and a greater risk of all-cause mortality in patients with breast cancer. Additional studies are needed to elucidate the causal pathways and mechanisms linking AL, neighborhood factors, and patient outcomes.

Household Food Security Status and Allostatic Load among United States Adults: National Health and Nutrition Examination Survey 2015-2020.

BACKGROUND: Household food insecurity has been linked to adverse health outcomes, but the pathways driving these associations are not well understood. The stress experienced by those in food-insecure households and having to prioritize between food and other essential needs could lead to physiologic dysregulations [i.e., allostatic load (AL)] and, as a result, adversely impact their health. OBJECTIVE: To assess the association between household food security status and AL and differences by gender, race and ethnicity, and Supplemental Nutrition Assistance Program (SNAP) participation. METHODS: We used data from 7640 United States adults in the 2015-2016 and 2017-March 2020 National Health and Nutrition Examination Survey to estimate means and prevalence ratios (PR) for AL scores (based on cardiovascular, metabolic, and immune biomarkers) associated with self-reported household food security status from multivariable linear and logistic regression models. RESULTS: Adults in marginally food-secure [mean = 3.09, standard error (SE) = 0.10] and food-insecure households (mean = 3.05; SE = 0.08) had higher mean AL than those in food-secure households (mean = 2.70; SE = 0.05). Compared with adults in food-secure households in the same category, those more likely to have an elevated AL included: SNAP participants [PR = 1.12; 95% confidence interval (CI):  1.03, 1.22] and Hispanic women (PR = 1.20; 95% CI: 1.05, 1.37) in marginally food-secure households; and non-Hispanic Black women (PR = 1.14; 95% CI: 1.03, 1.26), men (PR = 1.13; 95% CI: 1.02, 1.26), and non-SNAP non-Hispanic White adults (PR = 1.22; 95% CI: 1.08, 1.39) in food-insecure households. CONCLUSIONS: AL may be one pathway by which household food insecurity affects health and may vary by gender, race and ethnicity, and SNAP participation.

Allostatic load in children: The cost of empathic concern.

Early-life adversity affects long-term health outcomes but there is considerable interindividual variability in susceptibility to environmental influences. We proposed that positive psychological characteristics that reflect engagement with context, such as being concerned about people or performance on tasks (i.e., empathic concern), could moderate the interindividual variation in sensitivity to the quality of the early environment. We studied 526 children of various Asian nationalities in Singapore (46.6% female, 13.4% below the poverty line) with longitudinal data on perinatal and childhood experiences, maternal report on empathic concern of the child, and a comprehensive set of physiological measures reflecting pediatric allostatic load assessed at 6 y of age. The perinatal and childhood experiences included adversities and positive experiences. We found that cumulative adverse childhood experience was positively associated with allostatic load of children at 6 y of age at higher levels of empathic concern but not significantly associated at lower levels of empathic concern. This finding reveals evidence for the importance of empathic concern as a psychological characteristic that moderates the developmental impact of environmental influences, serving as a source for vulnerability to adversities in children.

Association between adverse childhood experiences and later-life allostatic load in UK Biobank female participants.

BACKGROUND: Adverse childhood experiences during key developmental periods have been shown to impact long-term health outcomes. Adverse childhood experiences may include psychological, physical, or sexual abuse; neglect; or socioeconomic factors. Adverse childhood experiences are linked with an increase in poor health behavior such as smoking and alcohol consumption, and may also influence epigenetic changes, inflammatory response, metabolic changes, and allostatic load. OBJECTIVE: We sought to explore associations between adverse childhood experiences and allostatic load in adult female participants in the UK Biobank. DESIGN: The UK Biobank is a multisite cohort study established to capture lifestyle, environment, exposure, health history, and genotype data on individuals in the United Kingdom. METHODS: Adverse childhood experiences were assessed from the Childhood Trauma Screener, which measures abuse and neglect across five items. Biological measures at enrollment were used to construct allostatic load, including measures of metabolic, inflammatory, and cardiovascular function. Females with a cancer diagnosis prior to enrollment were removed as it may influence allostatic load. Poisson regression models were used to assess the association between adverse childhood experiences and allostatic load, accounting for a priori confounders. RESULTS: A total of 33,466 females with complete data were analyzed, with a median age at enrollment of 54 (range = 40-70) years. Among the study sample, the mean allostatic load ranged from 1.85 in those who reported no adverse childhood experiences to 2.45 in those with all adverse childhood experiences reported. In multivariable analysis, there was a 4% increase in average allostatic load among females for every additional adverse childhood experience reported (incidence rate ratio = 1.04, 95% confidence interval = 1.03-1.05). Similar results were observed when assessing individual adverse childhood experience components. CONCLUSION: This analysis supports a growing body of evidence suggesting that increased exposure to early life abuse or neglect is associated with increased allostatic load in females.

Cellular allostatic load is linked to increased energy expenditure and accelerated biological aging.

Stress triggers anticipatory physiological responses that promote survival, a phenomenon termed allostasis. However, the chronic activation of energy-dependent allostatic responses results in allostatic load, a dysregulated state that predicts functional decline, accelerates aging, and increases mortality in humans. The energetic cost and cellular basis for the damaging effects of allostatic load have not been defined. Here, by longitudinally profiling three unrelated primary human fibroblast lines across their lifespan, we find that chronic glucocorticoid exposure increases cellular energy expenditure by ∼60%, along with a metabolic shift from glycolysis to mitochondrial oxidative phosphorylation (OxPhos). This state of stress-induced hypermetabolism is linked to mtDNA instability, non-linearly affects age-related cytokines secretion, and accelerates cellular aging based on DNA methylation clocks, telomere shortening rate, and reduced lifespan. Pharmacologically normalizing OxPhos activity while further increasing energy expenditure exacerbates the accelerated aging phenotype, pointing to total energy expenditure as a potential driver of aging dynamics. Together, our findings define bioenergetic and multi-omic recalibrations of stress adaptation, underscoring increased energy expenditure and accelerated cellular aging as interrelated features of cellular allostatic load.

Association of Allostatic Load With All-Cause Mortality in Patients With Breast Cancer.

Importance: Elevated allostatic load (AL) has been associated with adverse socioenvironmental stressors and tumor characteristics that convey poor prognosis in patients with breast cancer. Currently, the association between AL and all-cause mortality in patients with breast cancer is unknown. Objective: To examine the association between AL and all-cause mortality in patients with breast cancer. Design, Setting, and Participants: This cohort study used data from an institutional electronic medical record and cancer registry at the National Cancer Institute Comprehensive Cancer Center. Participants were patients with breast cancer diagnoses (stage I-III) between January 1, 2012, through December 31, 2020. Data were analyzed from April 2022 through November 2022. Exposure: AL was expressed as a summary score calculated by assigning 1 point for biomarkers in the worst sample quartile. High AL was defined as AL greater than the median. Main Outcomes and Measures: The main outcome was all-cause mortality. A Cox proportional hazard models with robust variance tested the association between AL and all-cause mortality. Results: There were 4459 patients (median [IQR] age, 59 [49-67] years) with an ethnoracial distribution of 3 Hispanic Black patients (0.1%), 381 non-Hispanic Black patients (8.5%), 23 Hispanic White patients (0.5%), 3861 non-Hispanic White patients (86.6%), 27 Hispanic patients with other race (0.6%), and 164 non-Hispanic patients with other race (3.7%). The mean (SD) AL was 2.6 (1.7). Black patients (adjusted relative ratio [aRR], those with 1.11; 95% CI, 1.04-1.18), single marital status (aRR, 1.06; 95% CI, 1.00-1.12), and those with government-supplied insured (Medicaid aRR, 1.14; 95% CI, 1.07-1.21; Medicare aRR, 1.11; 95% CI, 1.03-1.19) had a higher adjusted mean AL than those who were White, married/living as married, or privately insured, respectively. Adjusting for sociodemographic, clinical, and treatment factors, high AL was associated with a 46% increase in mortality risk (hazard ratio [HR], 1.46; 95% CI, 1.11-1.93) over low AL. Similarly, compared with patients in the first AL quartile, those in the third quartile (HR, 1.53; 95% CI, 1.07-2.18) and the fourth quartile (HR, 1.79; 95% CI, 1.16-2.75) had significantly increased risks of mortality. There was a significant dose-dependent association between increased AL and a higher risk of all-cause mortality. Furthermore, AL remained significantly associated with higher all-cause mortality after adjusting for the Charlson Comorbidity Index. Conclusions and Relevance: These findings suggest increased AL is reflective of socioeconomic marginalization and associated with all-cause mortality in patients with breast cancer.

Socioeconomic status, positive experiences, and allostatic load.

OBJECTIVE: Socioeconomic disparities in physiological well-being may be a pathway to the poorer health outcomes observed in those of lower socioeconomic status (SES). The present research examined greater frequency of positive life experiences (POS) as a route through which greater cumulative SES (CSES) may be linked to lower allostatic load (AL), a multisystem index of physiological dysregulation, and assessed whether the association between POS and AL varies along the socioeconomic spectrum. METHOD: These associations were examined using data from the Midlife Development in the United States Biomarker Project (N = 2,096). Analyses included tests of whether positive experiences mediated the CSES-AL association, whether CSES moderated associations of positive experiences and AL, and whether CSES moderated positive experience mediation of the CSES-AL association (moderated mediation). RESULTS: The observed association between CSES and AL was weakly mediated by POS. CSES moderated the POS-AL association, such that POS was associated with AL only at lower levels of CSES. The moderated mediation analysis showed that POS mediated the association between CSES and AL only at lower levels of CSES. CONCLUSIONS: The results suggest complexity in associations between cumulative socioeconomic advantage, positive life events, and physiological well-being. Positive life events may play a stronger role in physiological health in those of lower socioeconomic advantage, as one of multiple pathways through which lower SES is linked to poor health. Given the modifiability of access to, and frequency of, positive life events, the potential role of positive experiences in lessening health disparities warrants further study. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Allostatic Load and Cognitive Function Among Urban Adults in the Healthy Aging in Neighborhoods of Diversity across the Life Span Study.

BACKGROUND: Cross-sectional studies have linked cognition to allostatic load (AL) which reflects multisystem dysregulation from life course exposure to stressors. OBJECTIVE: To examine baseline and changes in AL and their relationships with 11 cognitive function test scores, while exploring health disparities according to sex and race. METHODS: Longitudinal [Visit 1 (2004-2009) and Visit 2 (2009-2013)] data were analyzed from 2,223 Healthy Aging in Neighborhoods of Diversity across the Life Span participants. We calculated AL total score using cardiovascular, metabolic, and inflammatory risk indicators, and applied group-based trajectory modeling to define AL change. RESULTS: Overall and stratum-specific relationships were evaluated using mixed-effects linear regression models that controlled for socio-demographic, lifestyle, and health characteristics. Baseline AL was significantly associated with higher log-transformed Part A Trail Making Test score [Loge (TRAILS A)] (ß= 0.020, p = 0.004) and increasing AL was associated with higher Benton Visual Retention Test score [BVRT] (ß= 0.35, p = 0.002) at baseline, in models that controlled for age, sex, race, poverty status, education, literacy, smoking, drug use, the 2010 healthy eating index and body mass index. Baseline AL and AL change were not related to change in cognitive function between visits. There were no statistically significant interaction effects by sex or race in fully-adjusted models. CONCLUSION: At baseline, AL was associated with worse attention or executive functioning. Increasing AL was associated with worse non-verbal memory or visuo-constructional abilities at baseline. AL was not related to change in cognitive function over time, and relationships did not vary by sex or race.

From financial wealth shocks to ill-health: Allostatic load and overload.

A number of studies have associated financial wealth changes with health-related outcomes arguing that the effect is due to psychological distress and is immediate. In this paper, I examine this relationship for cumulative shocks to the financial wealth of American retirees using the allostatic load model of pathways from stress to poor health. Wealth shocks are identified from Health and Retirement Study reports of stock ownership along with significant negative discontinuities in high-frequency S&P500 index data. I find that a one standard deviation increase in cumulative shocks over two years increases the probability of elevated blood pressure by 9.5%, increases waist circumference by 1.2% and the cholesterol ratio by 6.1% for those whose wealth is all in shares. My findings suggest that the combined effect of random shocks to financial wealth over time is salient for health outcomes. This is consistent with the allostatic load model in which repeated activation of stress responses leads to cumulative wear and tear on the body.

Longitudinal association of allostatic load with depressive symptoms among urban adults: Healthy Aging in Neighborhoods of Diversity across the Life Span study.

BACKGROUND: Evidence suggests that lifetime exposure to stressful life events and chronic stressors may be linked to geriatric depression. Allostatic load (AL) is considered a mediator of the stress-health relationship and has been linked to psychosocial factors reflecting health disparities. The purpose of this study was to examine the longitudinal associations of AL with depressive symptoms scores among urban adults, before and after stratifying by sex and race. METHODS: Secondary analyses were performed using Visit 1 (2004-2009), Visit 2 (2009-2013) and Visit 3 (2013-2017) data collected on 2298 Healthy Aging in Neighborhoods of Diversity across the Life Span study participants (baseline age: 30-64 y). AL at Visit 1 (ALv1) and z-transformed probability of higher AL trajectory (ALtraj) between Visits 1 and 3 were calculated using cardiovascular, metabolic and inflammatory risk indicators. The 20-item Center for Epidemiologic Studies Depression (CES-D) scale was used to calculate total and domain-specific depressive symptoms scores. Mixed-effects linear models controlled for socio-demographic, lifestyle and health characteristics. RESULTS: In fully adjusted models, a positive cross-sectional relationship was observed between ALv1 and "somatic complaints" depressive symptoms (ß = 0.21, P = 0.006) score at Visit 1, whereas ALtraj was associated with increasing depressive symptoms score (ß = 0.086, P = 0.003) between Visits 1 and 3. An inverse relationship was observed between ALtraj and "positive affect" depressive symptoms score at Visit 1 among women (ß = -0.31, P < 0.0001) and White adults (ß = -0.32, P = 0.004). Among women, ALtraj was also positively related to change in "somatic complaints" depressive symptoms score between Visits 1 and 3 (ß = 0.043, P = 0.020). CONCLUSIONS: Among urban adults, AL may be associated with "somatic complaints" depressive symptoms at baseline. Higher AL trajectories may predict increasing depressive symptoms (overall) and increasing "somatic complaints" depressive symptoms (among women). A higher AL trajectory may be associated with lower "positive affect" depressive symptoms at baseline among women and White adults only.

Intergenerational Social Mobility and Allostatic Load in Midlife and Older Ages: A Diagonal Reference Modeling Approach.

OBJECTIVES: This study aims to understand the association of life-course intergenerational social mobility with allostatic load (AL) burden in midlife and older ages in Ireland. METHODS: The study involved biological data for 3,987 older adults participating in The Irish Longitudinal Study on Ageing (TILDA). Intergenerational social mobility was characterized using the cross-classification of origin socioeconomic position (SEP; i.e., father's occupation) and destination SEP (i.e., own occupation). AL was operationalized using 12 biomarkers tapping cardiovascular, metabolic, renal, and immune system dysregulation. Diagonal reference modeling (DRM) and ordinary least square regression techniques were applied to explore the effect of social mobility on AL burden. RESULTS: A total of 55.5% experienced intergenerational mobility: 37.5% were upwardly mobile, 18.0% were downwardly mobile. A social gradient in AL was observed among the socially non-mobile. Destination SEP (b = 0.74, 95% CI = 0.57, 0.92) predominated in influence over origin, although both life stages exerted significant influence on later-life AL. Social mobility in either direction was not associated with AL burden. Mobility coefficients were substantially small across a large variety of model specifications. DISCUSSION: Findings provide evidence for an accumulation model of social inequalities in which disparities in health are diluted rather than increased by social mobility (i.e., gradient constraint), with the socially mobile having an AL score that is intermediate between their origin class and destination class. This implies that the effects of origin SEP on health are not immutable, but are instead responsive to changing socioeconomic circumstances across the life course.

Impact of subjective and objective neighbourhood characteristics and individual socioeconomic position on allostatic load: A cross-sectional analysis of an all-age UK household panel study.

Research suggests that individuals living in more disadvantaged neighbourhoods experience higher levels of stress but this has generally been based on self-reported stress. We used survey-based neighbourhood quality indicators and biomarker data from Understanding Society, linked to census and crime statistics to explore associations of allostatic load (AL), an objective biomarker-based measure of cumulative stress, with subjective and objective neighbourhood characteristics. Analyses of 6887 respondents living in England show greater AL among those living in more disadvantaged areas, with objective measure associations stronger than subjective. Neighbourhood inequalities in AL were lower among respondents with higher individual SEP. These results suggest that individual-level SEP mitigates against the impact of negative, particularly objective, neighbourhood characteristics. Policies to reduce health inequalities should consider both individual and neighbourhood circumstances.

Breastfeeding Duration Is Inversely Associated with Postpartum Allostatic Load: A Possible Mechanism for Improved Maternal Health.

Background: Allostatic load, a multisystem composite measure of chronic stress reflecting the cumulative wear and tear on the body, has utility in explaining maternal and child health disparities and predicting future health when measured during the peripartum period. Research using cross-sectional data has demonstrated an inverse association between concurrent breastfeeding status and maternal postpartum allostatic load. However, the relationship between breastfeeding duration and postpartum allostatic load has not been determined. Objective: This study aimed to examine the association between breastfeeding duration and postpartum allostatic load using prospective data, and to compare the association by race/ethnicity to better understand etiologies of health inequities. Materials and Methods: A secondary analysis of a data sample of 1,791 postpartum women from the Community Child Health Research Network was conducted. Multiple linear regression tested the association between and breastfeeding duration and allostatic load (range 0-10, calculated from 10 biomarkers) at 6 and 12 months postpartum, adjusting for race/ethnicity, maternal age, education, poverty level, study center, smoking, marital status, and prepregnancy body mass index. Stratified analyses examined differences in associations by race/ethnicity. Results: Breastfeeding duration was inversely associated with maternal allostatic load. In adjusted models, mothers who breastfed ≥6 months had 0.41 points lower allostatic load at 6 months (95% CI: -0.71 to -0.11) and 0.36 points lower allostatic load at 12 months postpartum (95% CI: -0.69 to -0.036) compared with mothers who never breastfed. Effect sizes varied in strength and significance across race/ethnic groups. Conclusions: Study findings suggest that extended breastfeeding for at least 6 months is linked with reduced chronic stress load in mothers during the first year postpartum. The inconsistency of findings across race/ethnic groups signals the importance of adjusting for prepregnancy allostatic load in future studies.

Sexual minority health and allostatic load in the National Health and Nutrition Examination Survey: A systematic scoping review with intersectional implications.

Understood largely from a minority stress framework, sexual minorities (SM) are hypothesized to suffer more physical and mental health burdens compared to their heterosexual counterparts. Several studies have used data from the National Health and Nutrition Examination Survey (NHANES) in the United States to assess SM health disparities and the 'wear and tear' of allostatic load. Because findings are generally mixed and sometimes contradictory with sexual minority stress theory, we endeavoured to explore existing NHANES studies of SM health. Our scoping review yielded a comprehensive analysis of all existing published articles (N = 43) that have used the NHANES to assess any outcome regarding SM health and well-being. Our synthesis confirms that SM sub-groups are significantly different from one another and from their heterosexual peers on several key health variables. Surprisingly, gay men appear to have the lowest allostatic load and no differences have yet been identified among women as a function of sexual identity/behavior. The existing literature suggests a need to use the NHANES more broadly and to include more psychosocial variables to better delineate sexual minority stress. This is especially important to consider at a physiological level in allostatic load research that should better include health behaviors available in NHANES and from other available datasets as moderators linking psychosocial exposures (e.g., minority stress) and health outcomes. Suggested future directions are proposed in an intersectional perspective that incorporates interactions among sex, gender, sexual identity/behaviors, race, ethnicity, age cohorts, socioeconomic status, and lived experiences.