Accelerated Epigenetic Aging in Peripheral Blood does not Predict Dementia Risk
P D Fransquet1, P Lacaze1, R Saffery2
1School of Public Health and Preventive Medicine, Monash University, Melbourne, 3004, Victoria, Australia.
Current Alzheimer Research
|August 25, 2021
Summary
Accelerated epigenetic aging, measured by DNA methylation clocks, did not strongly predict dementia risk in this study. While some acceleration was noted in males, overall findings suggest limited predictive value for dementia.
Area of Science:
- Epigenetics
- Aging Research
- Neurodegenerative Diseases
Background:
- Epigenetic age acceleration is linked to increased mortality and disease risk.
- Evidence connecting accelerated epigenetic aging to dementia risk is currently limited.
Purpose of the Study:
- To investigate if epigenetic biomarkers of aging can predict dementia risk.
- To address the role of aging as a primary dementia risk factor.
Main Methods:
- DNA methylation was analyzed in blood samples from 160 participants (73 pre-symptomatic dementia cases, 87 controls) from the ASPirin in Reducing Events in the Elderly study.
- Epigenetic age was calculated using Horvath, Hannum, GrimAge, and PhenoAge clocks.
- Age acceleration was determined as the difference between epigenetic and chronological age.
Main Results:
- No significant difference in overall age acceleration was found between dementia cases and controls.
- A modest increase in Hannum's intrinsic epigenetic age acceleration was observed in pre-symptomatic male dementia cases (Δ +1.8 years, p = 0.03).
Conclusions:
- The study found no robust evidence that peripheral blood epigenetic age acceleration predicts dementia risk.
- Current epigenetic aging biomarkers may have limited utility in predicting dementia onset.
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