Differential treatment effect on measures of neurologic exam,functional impairment and patient self-report in multiple sclerosis

Abstract

Objective: To determine the relative sensitivity of the Expanded Disability Status Scale (EDSS), the newly developed MS Functional Composite (MSFC) and the Guy's Neurological Disability Scale (GNDS) to changes in the neurological condition of Multiple Sclerosis (MS) patients induced by treatment with intravenous methylprednisolone (IV-MP). Methods: Sixty MS patients were treated with IV-MP. On the first day of treatment patients were trained for the three domains of the MSFC; on the second day baseline data were obtained for all measurements. Follow-up data were obtained 6-8 weeks after IV-MP treatment. Results: Significant changes were found for both EDSS and GNDS. Remarkably, the improvements on the GNDS were mainly due to changes in the subcategories cognition, speech, fatigue and `others'. No significant change was found for the MSFC. Forty-seven patients reported a subjective improvement in their condition. Twenty-one patients showed a significant improvement in the EDSS, 28 patients showed a significant improvement in the GNDS and a very small number of significant changes were found on the MSFC (actual number depending on the definition of the reference population). Conclusion: The observations in this study show that the relative sensitivity to change in acute or subacute deterioration in MS patients, is low for the MSFC and high for the GNDS. It is obvious from this study that such a treatment can have a differential effect on measurements of functional impairment, rating of neurologic examination and patient self-report.