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

Objective: To determine the relative sensitivity of the Expanded Disability Status Scale (EDSS), the newly developed MS Functional Composite (MSFC) an d the Guy's Neurological Disability Scale (GNDS) to changes in the neurolog ical condition of Multiple Sclerosis (MS) patients induced by treatment wit h intravenous methylprednisolone (IV-MP). Methods: Sixty MS patients were t reated 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 obtaine d 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 chang e was found for the MSFC. Forty-seven patients reported a subjective improv ement in their condition. Twenty-one patients showed a significant improvem ent in the EDSS, 28 patients showed a significant improvement in the GNDS a nd a very small number of significant changes were found on the MSFC (actua l number depending on the definition of the reference population). Conclusi on: The observations in this study show that the relative sensitivity to ch ange 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 ra ting of neurologic examination and patient self-report.