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Socio-Economic Position Under the Microscope: Getting ‘Under the Skin’ and into the Cells

  • Cathal McCroryEmail author
  • Sinead McLoughlin
  • Aisling M. O’Halloran
Social Epidemiology (J Dowd, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Social Epidemiology

Abstract

Purpose of the Review

Recent developments in the field of genetics and epigenetics are advancing our understanding of how socio-economic adversity throughout the life course gets embodied at a more fundamental level to accelerate the ageing process. This review summarises current research in relation to two candidate mechanisms: DNA methylation and telomere attrition that have been touted to provide biological intermediaries between socio-economic position and health.

Recent Findings

Although many studies have documented cross-sectional associations between measures of socio-economic position and these ‘hallmarks of ageing’, prospective studies tend to be more ambivalent, and additional work is required to understand whether they mediate the SEP-health link. Nevertheless, there appears to be good evidence that early childhood may represent a critical/sensitive period for the biological embedding of social adversity via these mechanisms.

Summary

Social epidemiology is making huge strides in advancing our understanding of how social influences get transduced at the biological level to precipitate earlier disease, morbidity and mortality of the socially disadvantaged. Enhanced understanding of these processes may help inform intervention/prevention efforts by suggesting at what stage during the life course it is most efficacious to intervene, and the extent to which these biological embedding processes are modifiable/reversible.

Keywords

Socio-economic position Biological ageing Age acceleration DNA methylation Telomere attrition Health disparities 

Notes

Funding Information

Cathal McCrory and Sinead McLoughlin are supported by the Health Research Board (HRB) of Ireland under an Emerging Investigator Award (EIA-2017-012).

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.

Disclaimer

The funders had no input or involvement in the authorship of the manuscript.

References

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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Cathal McCrory
    • 1
    Email author
  • Sinead McLoughlin
    • 1
  • Aisling M. O’Halloran
    • 1
  1. 1.The Irish Longitudinal Study on Ageing (TILDA)Trinity College DublinDublinIreland

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