Research Paper Volume 14, Issue 13 pp 5311—5344
Epigenetic clocks and their association with trajectories in perceived discrimination and depressive symptoms among US middle-aged and older adults
- 1 Laboratory of Epidemiology and Population Sciences, NIA/NIH/IRP, Baltimore, MD 21224, USA
- 2 Department of Research Programs, Fort Belvoir Community Hospital, Fort Belvoir, VA 22060, USA
- 3 Department of Psychology, University of Maryland, Baltimore County, Catonsville, MD 21250, USA
- 4 Department of Demography, University of California Berkeley, Berkeley, CA 94720, USA
Received: March 15, 2022 Accepted: June 1, 2022 Published: July 1, 2022
https://doi.org/10.18632/aging.204150How to Cite
Copyright: © 2022 Beydoun et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Background: Perceived discrimination may be associated with accelerated aging later in life, with depressive symptoms acting as potential mediator.
Methods: A nationally representative sample of older adults was used [Health and Retirement Study 2010–2016, Age: 50–100 y in 2016, N = 2,806, 55.6% female, 82.3% Non-Hispanic White (NHW)] to evaluate associations of perceived discrimination measures [Experience of discrimination or EOD; and Reasons for Perceived discrimination or RPD) and depressive symptoms (DEP)] with 13 DNAm-based measures of epigenetic aging. Group-based trajectory and four-way mediation analyses were used.
Results: Overall, and mostly among female and NHW participants, greater RPD in 2010–2012 had a significant adverse total effect on epigenetic aging [2016: DNAm GrimAge, DunedinPoAm38 (MPOA), Levine (PhenoAge) and Horvath 2], with 20–50% of this effect being explained by a pure indirect effect through DEP in 2014–2016. Among females, sustained elevated DEP (2010–2016) was associated with greater LIN DNAm age (β ± SE: +1.506 ± 0.559, p = 0.009, reduced model), patterns observed for elevated DEP (high vs. low) for GrimAge and MPOA DNAm markers. Overall and in White adults, the relationship of the Levine clock with perceived discrimination in general (both EOD and RPD) was mediated through elevated DEP.
Conclusions: Sustained elevations in DEP and RPD were associated with select biological aging measures, consistently among women and White adults, with DEP acting as mediator in several RPD-EPICLOCK associations.
Abbreviations
CES-D: Center for Epidemiologic Studies-Depression; CDE: Controlled Direct Effect; CI: Confidence Interval; DEP: Depressive Symptoms; DNAm: DNA methylation; EFTF: Enhanced Face to Face; EOD: Experience of Discrimination; EPICLOCK: Epigenetic Clock; HRS: Health and Retirement Study; INTMED: Mediated Interaction; INTREF: Interaction Referent; MDD: Major Depressive Disorder; Med4way: Four-way Mediation; MPOA: DunedinPoAm38 epigenetic clock; NHW: Non-Hispanic White; OLS: Ordinary Least Square; PhenoAge: Levine Epigenetic clock; RPD: Reasons for Perceived Discrimination; TE: Total Effect.