Mobilise-D aims to validate digital mobility outcomes (DMOs) in the largest longitudinal study of unsupervised walking in people with Multiple Sclerosis (pwMS) to date. Here, we describe the baseline gait quality characteristics which exist in progressive and relapsing multiple sclerosis (MS).

Loss of mobility is an important functional disability to pwMS. Whilst the Expanded Disability Status Scale (EDSS) remains the main disability outcome measure used in research and clinical practice, it does not discriminate between disease subtypes and lacks sensitivity to capture meaningful changes.

Unsupervised digital mobility assessment (DMA) aims to objectively measure real-world mobility.

602 adult pwMS (EDSS score of 3.0-6.5, disability worsening over the previous 2 years and a 30-day freedom from relapses) were recruited across four European centres. Over 24-months, 6-monthly clinical assessments are followed by 7 days of DMA using a waist-worn device. Valid DMA was considered as ≥3 days with ≥12hours wear time per day. A variety of DMOs were extracted from walking bouts >10s duration. Analysis was performed using a Mann-Whitney U test or spearman rank correlation, as appropriate, with significance set at p<0.05.

Participants had a mean age 52 years, 64% were female, and a median EDSS score of 5.0. 54% had relapsing remitting MS, 35% secondary progressive MS and 10% primary progressive MS.

Baseline DMA data is available for 92.4% participants with a mean wear time of 6.7 days indicating acceptability. From a mean 294 walking bouts per day, DMOs changed with disease severity (measured by EDSS and patient reported outcomes) and was different between progressive and relapsing subtypes.

Mobility monitoring is acceptable to patients, and can objectively discriminate between patients of different subtypes and disease severity.