The patient's perception of a (reliable) change in the Multiple Sclerosis Functional C omposite

Abstract

Objective: To prospectively character ize the relation between two-year changes in functional impairment as measured by the Multiple Sclerosis Functio nal C omposite (MSFC) and changes in patient perceived disability as measured by the Guy’s Neurological Disability Scale (GNDS). Methods: O ne hundred and eighty-eight patients with multiple sclerosis (MS) were recruited at our outpatient clinic. Impairment and disability were assessed using the MSFC and G NDS at baseline and follow-up. Longitudinal correlations were studied between changes in MSFC and GNDS and their corresponding components. We also studied changes in G NDS in relation to what can be classified as a reliable change in MSFC; for example, 20% change in each MSFC component or a change of 0.5 in total MSFC score. In addition, we studied the change in total number of GNDS subcategories with a score of 3 or higher in relation to the predefined MSFC changes, these subcategories being indicative of the requirement for help by another person. Results: Despite good cross-sectional correlations between MSFC and GNDS, no significant correlation was found between longitudinal changes in MSFC and GNDS. A nalysing the change in GNDS in relation to the predefined MSFC changes shows that G NDS changes are nicely rank ordered when more stringent definitions of reliable change were applied. In addition, analysing the number of G NDS subcategories scored 3 or higher indicate that there is a profile of worsening on the MSFC being associated with increase in the amount of help required from others. Conclusion: O ur longitudinal data suggest that a reliable change is associated with a likewise change in patient perceived disability, the smallest reliable change being identified by at least 20% change in each MSFC component.

Keywords

GNDS longitudinal study MS MSFC

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