Associations Between Loneliness, Epigenetic Aging, and Multimorbidity Through Older Adulthood.
Level 3 - non-randomized controlled study
Prospective cohort study analyzing longitudinal survey and biomarker data
PubMed 39417537 · doi:10.1093/geronb/gbae169
What was done
The authors analyzed data from 4,018 Health and Retirement Study participants who provided blood samples for DNA methylation profiling. They examined the relationships between baseline loneliness, epigenetic age acceleration (EAA measured via GrimAge), and the development of chronic health conditions (multimorbidity), testing whether EAA mediated or moderated the link between loneliness and multimorbidity while adjusting for demographic and behavioral covariates.
What was found
Baseline loneliness was significantly associated with accelerated GrimAge epigenetic aging after adjusting for covariates (beta = 0.07, p = .003). Both loneliness and GrimAge independently predicted increases in chronic condition counts over time. There was no statistically significant interaction (moderation) between loneliness and GrimAge, but GrimAge significantly mediated the relationship between loneliness and multimorbidity (indirect path beta = 0.020, p = .003).
Why it matters
This study provides biological evidence that epigenetic aging may be one mechanistic pathway linking perceived social isolation to worsening physical health and multimorbidity in older adults.
Limits
The abstract does not report whether other epigenetic clocks were tested alongside GrimAge. As an observational cohort study, residual confounding cannot be excluded, and the biological mediation effect size was small (beta = 0.020), indicating that other unmeasured biological and behavioral pathways likely account for most of the loneliness-health relationship.
Cited by
- supports Having a strong human bond, a reliable partner, or a pet slows biological aging and is associated with increased longevity compared to being lonely.