TY - JOUR
T1 - The Role of Epigenetic Clocks in Explaining Educational Inequalities in Mortality
T2 - A Multicohort Study and Meta-analysis
AU - Fiorito, Giovanni
AU - Pedron, Sara
AU - Lifepath consortium
AU - Ochoa-Rosales, Carolina
AU - McCrory, Cathal
AU - Polidoro, Silvia
AU - Zhang, Yan
AU - Dugué, Pierre Antoine
AU - Ratliff, Scott
AU - Zhao, Wei N.
AU - McKay, Gareth J.
AU - Costa, Giuseppe
AU - Solinas, Maria Giuliana
AU - Harris, Kathleen Mullan
AU - Tumino, Rosario
AU - Grioni, Sara
AU - Ricceri, Fulvio
AU - Panico, Salvatore
AU - Brenner, Hermann
AU - Schwettmann, Lars
AU - Waldenberger, Melanie
AU - Matias-Garcia, Pamela R.
AU - Peters, Annette
AU - Hodge, Allison
AU - Giles, Graham G.
AU - Schmitz, Lauren L.
AU - Levine, Morgan
AU - Smith, Jennifer A.
AU - Liu, Yongmei
AU - Kee, Frank
AU - Young, Ian S.
AU - McGuinness, Bernadette
AU - McKnight, Amy Jayne
AU - van Meurs, Joyce
AU - Voortman, Trudy
AU - Kenny, Rose A.
AU - Vineis, Paolo
AU - Carmeli, Cristian
N1 - Funding:
This work was supported by the European Commission [Grant Horizon
2020 number 633666]. G.F. is supported by Programma Operativo
Nazionale (PON), Ricerca e Innovazione 2014-2020, Attrazione e Mobilità
Internazionale (AIM) code AIM1874325-2. M.G.S. is supported by ‘Fondo di
Ateneo per la ricerca 2019’, University of Sassari, Italy.
Publisher Copyright:
© The Author(s) 2022. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
PY - 2022/9
Y1 - 2022/9
N2 - Educational inequalities in all-cause mortality have been observed for decades. However, the underlying biological mechanisms are not well known. We aimed to assess the role of DNA methylation changes in blood captured by epigenetic clocks in explaining these inequalities. Data were from 8 prospective population-based cohort studies, representing 13 021 participants. First, educational inequalities and their portion explained by Horvath DNAmAge, Hannum DNAmAge, DNAmPhenoAge, and DNAmGrimAge epigenetic clocks were assessed in each cohort via counterfactual-based mediation models, on both absolute (hazard difference) and relative (hazard ratio) scales, and by sex. Second, estimates from each cohort were pooled through a random effect meta-analysis model. Men with low education had excess mortality from all causes of 57 deaths per 10 000 person-years (95% confidence interval [CI]: 38, 76) compared with their more advantaged counterparts. For women, the excess mortality was 4 deaths per 10 000 person-years (95% CI: -11, 19). On the relative scale, educational inequalities corresponded to hazard ratios of 1.33 (95% CI: 1.12, 1.57) for men and 1.15 (95% CI: 0.96, 1.37) for women. DNAmGrimAge accounted for the largest proportion, approximately 50%, of the educational inequalities for men, while the proportion was negligible for women. Most of this mediation was explained by differential effects of unhealthy lifestyles and morbidities of the World Health Organization (WHO) risk factors for premature mortality. These results support DNA methylation-based epigenetic aging as a signature of educational inequalities in life expectancy emphasizing the need for policies to address the unequal social distribution of these WHO risk factors.
AB - Educational inequalities in all-cause mortality have been observed for decades. However, the underlying biological mechanisms are not well known. We aimed to assess the role of DNA methylation changes in blood captured by epigenetic clocks in explaining these inequalities. Data were from 8 prospective population-based cohort studies, representing 13 021 participants. First, educational inequalities and their portion explained by Horvath DNAmAge, Hannum DNAmAge, DNAmPhenoAge, and DNAmGrimAge epigenetic clocks were assessed in each cohort via counterfactual-based mediation models, on both absolute (hazard difference) and relative (hazard ratio) scales, and by sex. Second, estimates from each cohort were pooled through a random effect meta-analysis model. Men with low education had excess mortality from all causes of 57 deaths per 10 000 person-years (95% confidence interval [CI]: 38, 76) compared with their more advantaged counterparts. For women, the excess mortality was 4 deaths per 10 000 person-years (95% CI: -11, 19). On the relative scale, educational inequalities corresponded to hazard ratios of 1.33 (95% CI: 1.12, 1.57) for men and 1.15 (95% CI: 0.96, 1.37) for women. DNAmGrimAge accounted for the largest proportion, approximately 50%, of the educational inequalities for men, while the proportion was negligible for women. Most of this mediation was explained by differential effects of unhealthy lifestyles and morbidities of the World Health Organization (WHO) risk factors for premature mortality. These results support DNA methylation-based epigenetic aging as a signature of educational inequalities in life expectancy emphasizing the need for policies to address the unequal social distribution of these WHO risk factors.
UR - http://www.scopus.com/inward/record.url?scp=85134699894&partnerID=8YFLogxK
U2 - 10.1093/gerona/glac041
DO - 10.1093/gerona/glac041
M3 - Article
C2 - 35172329
AN - SCOPUS:85134699894
SN - 1079-5006
VL - 77
SP - 1750
EP - 1759
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
IS - 9
ER -
