The multiple sclerosis severity score (MSSS) predicts disease severity over time

Abstract: Background: The multiple sclerosis severity scale (MSSS) adds the element of disease duration to the expanded disease status score (EDSS) and is designed to provide a measure of disease severity. We have used this tool to address two questions: Can it be used to predict the accrual of disability over time in individual patients? Do the currently available therapies have an impact upon disease severity over time? Methods: All patients who were followed and treated by a single neurologist in an MS center in the USA over a two year period were evaluated. The MSSS was retrospectively tabulated in 195 MS patients and the course and severity of the disease was analyzed in a sample of 10 randomly selected patients. 177/195 (94%) of patients received disease-modifying therapies for at least a year during the period that was evaluated. Results: The mean duration of symptoms in our patients was 9.7 years (range 0.3–26) with an EDSS mean score of 3.5 (range 0–9.5). The average MSSS rating for the entire cohort of 195 patients was 48.7, similar to that observed in the European cohort. In 9/10 patients, randomly selected and representative of the entire group, the MSSS assessments were consistent over time and irrespective of therapy with a range over 5–12 years of disease duration averaging only 11.3 points (range 3.7–18.8). Conclusions: The MSSS may allow the prediction of disease severity over time, and is consistent with the lack of a major impact of disease-modifying drugs upon disease severity as measured by the MSSS. These results need to be verified in a larger cohort of patients. [Copyright &y& Elsevier]