Researchers found children living with multiple sclerosis show signs of accelerated biological aging, even in their teenage years. The research is the first to examine whether MS causes early aging in a pediatric population — offering new insight into the disease and its long-term progression.

MS is a lifelong autoimmune disease that attacks the brain, spinal cord and optic nerves. The research team used DNA methylation markers — molecular changes that indicate biological age — to analyze blood samples from 125 children with MS and 145 children without MS. In contrast to chronological age, which reflects the number of birthdays, biological age tracks how quickly the body is wearing down on a cellular level.

The study by researchers at the University of California – San Diego School of Medicine focused on children and teenagers not yet affected by the processes of normal aging and age-related illnesses such as hypertension and diabetes. Despite appearing outwardly healthy, children with MS showed DNA patterns indicating they were biologically older than their peers.

The researchers found differences in four different epigenetic clocks and signs of accelerated aging in MS patients in models of two clocks most sensitive to health-related stress and inflammation. Epigenetic clocks are age-predicting algorithms that calculate epigenetic age as an estimate of chronological age or age-associated clinical events such as disease or all-cause mortality. The most affected kids appeared to be aging up to two years faster biologically than their healthy peers, even though their average chronological age was just 15.

Biological age has already been linked to disability progression in adults with MS. This study suggests the process may start much earlier than previously thought, potentially even before visible symptoms of progression appear. And that could change the way MS is treated.

The researchers hope future studies will track patients over time to see how early biological aging contributes to long-term disability. They also plan to explore how social stressors, obesity, and environmental exposures may accelerate aging in children with MS, especially given the higher prevalence of pediatric MS among lower-income families.

The findings were published in the journal Neurology.