Online behavioral intervention increases physical activity and improves depression in newly diagnosed multiple sclerosis

This pilot randomized controlled trial evaluated a COM-B-based behavioral intervention for physical activity promotion in 50 people newly diagnosed with multiple sclerosis (disease duration ≤2 years). Participants were randomized to receive the 16-week online intervention (coaching and newsletters) or a waitlist control. The primary outcome was physical activity measured by device and self-report.

At post-intervention (16 weeks), the intervention group showed significant improvements in device-measured moderate-to-vigorous physical activity (increase of 11.2 min/day, 95% CI: 8.8, 13.7; d=0.5) and self-reported activity on the IPAQ (increase of 11.4 units, 95% CI: 10.4, 12.3; d=0.7) compared to control. Secondary analyses showed significant improvements in depression scores (HADS-D decrease of 1.4 units, 95% CI: 1.3, 1.5; d=0.5) and mental health-related quality of life (SF-12 MCS increase of 5.6 units, 95% CI: 5.1, 6.1; d=0.6). Effects on device-measured steps/day, light physical activity, fatigue, and anxiety were not reported as significant.

Safety and tolerability data were not reported. Key limitations include the pilot nature with small sample size (n=50), unblinded design, and short-term follow-up only to 16 weeks. The study did not report on adverse events, serious adverse events, or discontinuations. Funding and conflicts of interest were not reported.

This provides preliminary evidence that an online behavioral intervention may increase physical activity and improve depression and mental quality of life in people newly diagnosed with MS. The RCT design supports causal inference, but the pilot status, small sample, and lack of blinding limit confidence. Effects on other important outcomes like fatigue and long-term maintenance remain unknown. These findings require replication in larger, longer-term trials before clinical implementation.