Beneficial impact of physical activity on multiple sclerosis disability progression

Background Physical activity has been associated with neuroprotective and immunomodulatory benefits, potentially influencing long-term disability outcomes in multiple sclerosis (MS). However, longitudinal evidence on its role in modifying disease progression remains limited. Methods We analysed 3284 individuals with incident relapsing-remitting MS from the Swedish Epidemiologic Investigation of MS. Participants were followed for up to 15 years through the Swedish MS Registry. Physical activity at diagnosis was categorised into low, moderate, moderate-high and high activity. The primary outcomes were time to confirmed disability worsening (CDW) and progression to Expanded Disability Status Scale (EDSS) 3 and 4. Changes in physical activity post diagnosis were analysed in a subsample (n=1724). Cox regression models were used to estimate HRs adjusting for clinical and lifestyle factors. Results Higher levels of physical activity at diagnosis were associated with reduced risk of disability progression. Compared with low physical activity, the risk of CDW was reduced for moderate (HR 0.77, 95% CI 0.61 to 0.97), moderate-high (HR 0.71, 95% CI 0.54 to 0.94) and high physical activity (HR 0.64, 95% CI 0.46 to 0.90). Similar trends were observed for reaching EDSS 3 and EDSS 4. Increasing activity post-diagnosis was associated with more favourable outcomes, while physical activity before diagnosis showed no significant association with long-term disability progression. Conclusions Our findings suggest that physical activity may beneficially influence disease progression in MS. The observed associations highlight the importance of maintaining regular physical activity for ongoing clinical benefits. Our results support including physical activity promotion as a component of standard MS care to optimise long-term outcomes.