Wearable sensors as a MS monitoring tool

Wearable sensors may help identify people with multiple sclerosis (MS) who are more likely to have worsening disability and brain volume loss, according to a study published March 4, 2026, in Neurology^®the medical journal of the American Academy of Neurology.

The study found that people with changes in their activity patterns were more likely to have worsening disability and loss of brain volume compared to people whose patterns did not change as much or at all.

The study does not prove that changes in activity lead to MS progression. shows only a correlation.

Wearable sensors measure how much light, moderate, or vigorous physical activity people had during the day, how much time they spent sitting or being inactive, and their circadian rhythms, or sleep-wake patterns.

Early identification of patients at risk of disease progression is essential to reduce long-term disability, but current tests to measure MS disability are not designed to detect small changes. Using a relatively cheap and accessible device around the wrist can help us detect early changes in the disease.”

Kathryn C. Fitzgerald, ScD, ScM, Study Author and Assistant Professor, Neurology, Johns Hopkins University

The study involved 238 people with MS with an average age of 55 and who had lived with MS for an average of 13 years. At the start of the study, they had an average disability level of 3 on the Expanded Disability Status Scale, a scale that measures disability in multiple sclerosis, which indicates no problems with walking, but moderate disability in one of eight functional systems, such as muscle weakness, balance problems, or problems with thinking and memory, or mild disability in three or four domains.

The people had no other serious health problems that could affect their physical activity and had not had MS relapse within six months before the study.

Participants wore devices around their wrists 24 hours a day to measure their activity levels for two weeks. They did this every three months for an average of three years. They also had tests every six months to check their levels of disability. They took brain scans at the start of the study and after two years to look for any changes in the brain.

During the study, 120 people experienced disease progression. People who had reductions in their daily activity levels were more likely to have disease progression. People who had reductions in their activity levels in the first half of the day were about 20% more likely to have disease progression compared to people who had no reductions in their activity levels.

People who had reductions in their activity levels in the morning, from 8:00 a.m. to 10:00 a.m., they were more likely to have brain volume loss. Each standard deviation decrease in activity level was associated with a 0.18% decrease in total brain volume, as well as a 0.34% decrease in deep gray matter and a 0.35% loss in thalamic area of ​​the brain.

“More research is needed to confirm these findings, but it’s exciting to think that using easily accessible devices could help us predict who is at risk of worsening disease and potentially prevent these changes,” Mowry said. “Identifying small changes could also help us speed up research into new treatments.”

A limitation of the study is that it did not include a group of people who did not have MS, which would help researchers understand how activity levels may change as part of normal aging. Also, the participants were relatively older and more disabled, so the results may not apply to younger people with MS and people with less disability.