# Epigenetic Aging Signatures in People with Hemophilia

## TL;DR

This study explores whether people with severe hemophilia age faster biologically than those with mild hemophilia or healthy individuals, using epigenetic markers.

## Contribution

The study introduces a novel investigation into epigenetic aging in hemophilia using specific CpG markers.

## Key findings

- Deviations of epigenetic from chronological age were high, with systematic overprediction by the 3-CpG age estimators.
- Evidence for a different rate of biological aging in severe hemophilia compared to mild hemophilia or healthy controls was weak.
- Hemophilic arthropathy was associated with an increased rate of biological aging.

## Abstract

Hemophilia is a rare X-linked bleeding disorder leading to recurrent hemarthroses, hemophilic arthropathy, and impaired quality of life. A chronic lifelong disease, hemophilia might be associated with accelerated biological aging. Here, we investigated whether biological age derived from epigenetic age estimators differs in hemophilia.

We collected blood samples from men with severe (<1 IU/dL; PWSH,
n
 = 20) or mild hemophilia (≥5 IU/dL; PWMH,
n
 = 20), and age-matched healthy male controls (
n
 = 20). DNA methylation of cytosine–phosphate–guanine (CpG) dinucleotides at five genes (
ASPA
,
ITGA2B
,
PDE4C
,
FHL2
,
CCDC10SB
) was measured by bisulfite pyrosequencing. Biological age was estimated using two epigenetic aging signatures, each including three CpGs. We investigated differences in biological age and the rate of biological aging between study groups using separate linear regressions on chronological age and study group without and with an interaction, respectively.

Deviations of epigenetic from chronological age were high for both 3-CpG age estimators, with results suggesting systematic overprediction. In both linear regressions using the two 3-CpG estimates, respectively, evidence for a different rate of biological aging in severe hemophilia was weak. The rate of biological aging in PWSH was 0.24 (95% CI, 0.01–0.48) and 0.21 (0.04–0.37) higher compared with PWMH, and 0.05 (−0.19–0.29) and 0.17 (−0.00–0.34) higher compared with healthy controls, respectively. Hemophilic arthropathy was associated with an increased rate of biological aging.

Evidence for a difference in epigenetic aging as reflected by two 3-CpG estimators in severe compared with mild hemophilia or healthy controls was weak.