Socio‐economic differentials in peripheral biology: Cumulative allostatic load

Abstract

This chapter focuses on evidence linking socio-economic status (SES) to "downstream" peripheral biology. Drawing on the concept of allostatic load, we examine evidence linking lower SES with greater cumulative physiological toll on multiple major biological regulatory systems over the life course. We begin by reviewing evidence linking lower SES to poorer trajectories of aging in multiple, individual physiological systems, followed by evidence of the resulting cumulative, overall burdens of physiological dysregulation seen among those of lower SES. The role of cumulative physiological dysregulation in mediating SES gradients in morbidity and mortality is then examined. We conclude with discussion of the question of interactions between SES (and other such environmental factors) and genetic endowment, and their potential consequences for patterns of physiological activity-an area of research that appears poised to contribute significantly to our understanding of how social conditions "get under the skin" to affect health and aging.

Childhood abuse, parental warmth, and adult multisystem biological risk in the Coronary Artery Risk Development in Young Adults study

“…Individual system risk scores. For each system represented by biological parameters, we calculated a risk score by using the following groupings based on a previous confirmatory factor analysis (11): metabolic risk (waist circumference, triglycerides, HDL, LDL, glucose, insulin), inflammation risk (CRP, IL-6, fibrinogen), blood pressure risk (systolic and diastolic blood pressure), HRV risk (lowand high-frequency HRV, heart rate), SNS hormone risk (epinephrine and norepinephrine), and cortisol risk (AM rise and diurnal slope). Adult socioeconomic status.…”

“…In support of this, evidence of such forms of allostatic load have been observed across a number of physiological regulatory systems in relation to childhood toxic stress, including increased levels of hemoglobin A1c, elevated total cholesterol, higher adiposity, and metabolic syndrome (13)(14)(15). Likewise, neuroendocrine changes have been observed in individuals reporting childhood stress, such as greater sympathetic nervous system (SNS) activity, disrupted hypothalamicpituitary-adrenal (HPA) activity, and autonomic imbalance (11,16). Childhood toxic stress has also been associated with a less healthy cardiovascular system profile (e.g., elevated blood pressure), increases in inflammation suggestive of proinflammatory immune system programming, and accelerated cellular aging (17)(18)(19)(20)(21)(22)(23)(24)(25).…”

“…Such demands lead to a state of chronic dysregulation across multiple systems, termed allostatic load. Toxic childhood stress may alter stress response patterns through more frequent elicitation, excessive activation, and alterations in the counterregulatory capacity to down-regulate activity, all of which may contribute to chronic alterations in these regulatory systems (10)(11)(12). In support of this, evidence of such forms of allostatic load have been observed across a number of physiological regulatory systems in relation to childhood toxic stress, including increased levels of hemoglobin A1c, elevated total cholesterol, higher adiposity, and metabolic syndrome (13)(14)(15).…”

Social Determinants of Risk and Outcomes for Cardiovascular Disease

“…Chronic elevation of one's allostatic load over a period of years can have harmful effects on many organ systems, especially the cardiovascular system. 278,[293][294][295] A principal site of the harm caused by chronically elevated allostatic load is the arterial circulation. Long-term elevation of cortisol and other stress response hormones triggers an inflammatory response in the endothelial cells lining the arteries and arterioles, leading to the release of inflammatory cytokines and other markers of inflammation.…”

Social disadvantage, genetic sensitivity, and children’s telomere length

“…A key mechanism for explaining this association is chronic stress, which is believed to degrade physiological functioning (3)(4)(5)(6), thus "weathering" the individual and making him or her less resistant to disease (7,8). We examined (i) whether the association between exposure to a disadvantaged environment and stress biomarkers was evident in childhood and (ii) whether the association was more pronounced for children carrying specific genetic variants.…”