Enhanced EDSS Instrument Helpful in Assessing Disability Progression in People with MS
In a recent study presented at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum 2025, a novel assessment tool for measuring multiple sclerosis (MS) disease progression showed utility for redefining and quantifying progression independent of relapse activity (PIRA). The Expanded Disability Status Scale (EDSS)-Plus score combines the traditional EDSS with functional assessments including the 9-Hole Peg Test (9HPT) and Timed 25-Foot Walk Test (T25FWT).
The prospective study included 741 individuals with relapsing MS. Researchers standardized the EDSS, 9HPT, and T25FWT raw scores using z-scores and defined PIRA as sustained disability progression in at least 1 of these measures (EDSS progression or a 20% increase in 9HPT or T25FWT) over 3 months, without signs of relapse 30 days before or after the initial disability increase. The study also evaluated demographic and clinical factors such as age, gender, number of relapses, treatment history, and disease duration to assess their impact on PIRA and EDSS-Plus scores.
Results showed that 19.7% of participants experienced PIRA, with no significant difference between treatment groups (P>.05). However, EDSS-Plus scores were significantly different between groups with and without PIRA (P<.001). Furthermore, there were significant differences in EDSS-Plus scores across different disease-modifying therapy (DMT) groups (P<.001):
- First-line DMT, 0.28±0.29
- Second-line DMT, 0.16±0.48
- Third-line DMT, -0.60±0.98
The regression model revealed that age and the number of relapses were effective factors influencing the EDSS-Plus score (R2=.268). However, none of the demographic and clinical variables were shown to be effective factors in PIRA.
The findings highlight the potential for EDSS-Plus scores to redefine and quantify PIRA in MS patients. Combining multiple measures into a single score offers neurologists a more detailed and accurate method for assessing disability progression. This could lead to improved patient monitoring and more targeted treatment strategies in MS management.