Evaluation of epigenetic and metabolomic biomarkers indicating biological age

Biological age captures a person's age-related risk of unfavorable outcomes using biophysiological information. Multivariate biological age measures include frailty scores and molecular biomarkers. These measures are often studied in isolation, but here we present a large-scale study comparing them. In two prospective cohorts (n=3,196), we compared epigenetic (DNAm Horvath, DNAm Hannum, DNAm PhenoAge, DNAm GrimAge) and metabolomic-based (MetaboAge, MetaboHealth) biomarkers in reflection of biological age, as represented by five frailty measures and overall mortality. We observed that mortality-trained biological age markers, DNAm GrimAge and MetaboHealth, outperformed age-trained biomarkers in frailty reflection and mortality prediction. The associations of DNAm GrimAge and MetaboHealth with frailty and mortality were independent of each other and of the frailty score mimicking clinical geriatric assessment. Epigenetic, metabolomic, and clinical biological age markers seem to capture different aspects of aging. These findings suggest that mortality-trained molecular markers may provide novel phenotype reflecting biological age and strengthen current clinical geriatric health and well-being assessment.