Clocks out of sync: Increased epigenetic aging variability in multiple sclerosis

Area of Science:

• Epigenetics
• Aging Research
• Neuroimmunology

Background:

• Epigenetic clocks, based on DNA methylation, serve as biological age markers.
• Understanding biological aging in neurological disorders like multiple sclerosis (MS) is crucial.

Purpose of the Study:

• To investigate the variability of epigenetic age acceleration (EAA) in individuals with multiple sclerosis (MS) compared to healthy controls (HC).
• To assess differences in epigenetic aging variance across different MS subtypes (relapsing-remitting and secondary progressive) and healthy controls.

Main Methods:

• Utilized epigenetic clocks, specifically PhenoAge, to measure biological age.
• Compared the standard deviation of PhenoAge between MS patient groups and HC.
• Employed a likelihood ratio test to statistically evaluate differences in variance.

Main Results:

• Epigenetic age acceleration demonstrated significantly greater variability in MS patients compared to HC.
• The secondary progressive MS group showed a standard deviation 1.5 times greater than controls.
• A likelihood ratio test confirmed significant variance differences across relapsing remitting MS, SPMS, and HC groups (p=0.017).

Conclusions:

• The heterogeneity of epigenetic aging in MS is substantial.
• Future epigenetic aging studies in MS will necessitate larger sample sizes.
• Variance-aware sample size planning is essential for robust MS epigenetic research.