How does socio-economic position (SEP) get biologically embedded? A comparison of allostatic load and the epigenetic clock(s)
File(s)McCrory PNEC Manuscript.docx (104.7 KB)
Accepted version
Author(s)
Type
Journal Article
Abstract
Individuals of lower socio-economic position (SEP) carry a heavier burden of disease and morbidity and live shorter lives on average compared with their more advantaged counterparts. This has sparked research interest in the processes and mechanisms via which social adversity gets biologically embedded. The present study directly compares the empirical worth of two candidate mechanisms: Allostatic Load (AL) and the Epigenetic Clock(s) for advancing our understanding of embodiment using a sub-sample of 490 individuals from the Irish Longitudinal Study (TILDA) who were explicitly selected for this purpose based on their inter-generational life course social class trajectory. A battery of 14 biomarkers representing the activity of 4 different physiological systems: Immunological, Cardiovascular, Metabolic, and Renal was used to construct the AL score. Biomarkers were dichotomised into high and low risk groups according to sex-specific quartiles of risk and summed to create a count ranging from 0-14. Three measures of epigenetic age acceleration were computed according to three sets of age-associated Cytosine-phosphate-Guanine (CpG) sites described by Horvath, Hannum and Levine. AL was strongly socially patterned across a number of measures of SEP, while the epigenetic clocks were not. AL partially mediated the association between measures of SEP and an objective measure of physiological functioning: performance on the Timed Up and Go (TUG test). We conclude that AL may represent the more promising candidate for understanding the pervasive link between SEP and health.
Date Issued
2019-06-01
Date Acceptance
2019-02-15
Citation
Psychoneuroendocrinology, 2019, 104, pp.64-73
ISSN
0306-4530
Publisher
Elsevier
Start Page
64
End Page
73
Journal / Book Title
Psychoneuroendocrinology
Volume
104
Copyright Statement
© 2019 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Commission of the European Communities
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/30818253
PII: S0306-4530(18)31063-1
Grant Number
633666
Subjects
Allostatic load
Biological embedding
Epigenetic clock
Life Course
Socioeconomic position
Publication Status
Published
Coverage Spatial
England
Date Publish Online
2019-02-16