Intervening to reduce the risk of future disability from multiple sclerosis: are we there yet?

Disease-modifying therapies (DMTs) delay or may prevent the progression of patients with high-risk clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (MS), and from relapsing-remitting MS to secondary progressive MS. Current evidence on the effects of DMT on disability in MS is supported by the use of the Expanded Disability Status Scale (EDSS), which is dominated by ambulation, and usually used as a secondary outcome measure. Less is known about the long-term effects of DMTs on other aspects of functional status, particularly cognition, which is a key determinant of ability to work.