Evaluation of the T25FW in minimally disabled people with multiple sclerosis

Walking impairment is one of the most prevalent symptoms in people with multiple sclerosis (pwMS). In this study, we aimed to explore the usefulness of a simple walking test, the Timed 25 Foot Walk (T25FW), in detecting subtle differences in "fully ambulatory" pwMS compared to HC.

We therefore investigated retrospective data from a clinical real-life cohort of 650 pwMS. We first analyzed the amount of patients showing clinically relevant impairment in the T25FW (T25FW > 6 s) within different levels of disability according to the Expanded Disability Status Scale (EDSS). For detailed analysis in "fully ambulatory" pwMS, we formed four groups according to the respective levels of disability (EDSS 0, EDSS 1, EDSS 1.5-2, EDSS 2.5-3), and compared their walking speed to age- and sex-matched healthy controls (HC).

In our cohort, the number of patients showing clinically relevant slowing in the T25FW ranged from 15% in "fully ambulatory" patients (EDSS 0-3) to 69% in patients with moderate (EDSS 3.5-5.5) and 100% in patients with severe impairment (EDSS ≥6). Further analyses in "fully ambulatory" patients revealed that all EDSS-subgroups showed significant slowing compared to HC. The mean difference to walking speed of HC became gradually more pronounced from 0.15 m/s in asymptomatic patients (EDSS 0) to 0.5 m/s in patients with EDSS 2.5-3.

These findings underline the ability of the T25FW to detect slowing even in patients with minimal disability. While the difference to HC was slightly below clinical relevance in asymptomatic patients (EDSS 0), slowing gradually worsened from EDSS 1 onwards and exceeded published thresholds for clinical meaningfulness.