DNA methylation-based measures of biological age: meta-analysis predicting time to death.
Level 3 - non-randomized controlled study
Meta-analysis of observational cohort studies evaluating a prognostic biomarker
PubMed 27690265 · doi:10.18632/aging.101020
What was done
Researchers performed a meta-analysis across 13 cohorts totaling 13,089 individuals from three racial/ethnic groups (non-Hispanic whites, Hispanics, African Americans) to test whether DNA methylation estimates of biological age in blood predict time to death. They also evaluated whether adding blood cell composition data into epigenetic age metrics improved mortality prediction, adjusting for chronological age and traditional risk factors.
What was found
All evaluated measures of epigenetic age acceleration significantly predicted all-cause mortality independent of chronological age (p <= 8.2 x 10^-9). These associations remained statistically significant after adjusting for additional risk factors (p < 5.4 x 10^-4) and within each individual racial/ethnic group. Incorporating blood cell composition into epigenetic age metrics yielded the strongest association with time to death (p = 7.5 x 10^-43). Effect sizes such as hazard ratios and confidence intervals were not reported in the abstract.
Why it matters
This study provides large-scale multi-cohort evidence that blood DNA methylation measures of biological age predict all-cause mortality beyond chronological age and standard risk factors. It also shows that incorporating blood cell composition substantially improves mortality prediction.
Limits
The abstract provides p-values but omits effect sizes (hazard ratios, risk ratios) and confidence intervals. As an observational meta-analysis, it cannot establish causal mechanisms between epigenetic acceleration and death. Analysis was restricted to blood tissue and three racial/ethnic groups.
Cited by
- supports Faster biological aging as measured by DNA methylation epigenetic clocks predicts shorter lifespan, worse health, and earlier mortality.