Validation of the Guy's Neurological Disability Scale as a screening tool for cognitive impairment in multiple sclerosis

Abstract

Cognitive impairment is a common symptom affecting daily activities of the patients with multiple sclerosis (MS). Various cognitive evaluation tests are available, yet most of them are complex and time-consuming to perform in outpatient clinics. In this study, we aimed to validate a Japanese version of the Guy's Neurological Disability Scale (GNDS) as a user-friendly tool to evaluate comprehensive disabilities in MS including cognitive function. Questions of the GNDS were translated into Japanese and named GNDS-J. Forty-four patients were examined by the Expanded Disability Status Scale (EDSS), the Paced Auditory Serial Addition Test (PASAT), the Symbol Digit Modalities Test (SDMT), the vitality scale, and the GNDS-J in the same time at remission state. The GNDS-J scores correlated with the EDSS scores(r = 0.61), and inversely correlated with the PASAT2/1(r=-0.56/-0.49) scores and the SDMT scores (r=-0.68), whereas the GNDS-J did not show any correlation with the vitality scale. Furthermore, eleven patients were evaluated over 5 years for changes in these scores. Eight out of 11 patients had exacerbated GNDS, and all of these patients experienced clinical relapse during this period. The GNDS-J is a valid tool to perform in outpatient clinics, which could provide a comprehensive scale for evaluating symptoms of MS, thus the disease activity by repeated measure.