Can clinical outcomes be used to detect neuroprotection in multiple sclerosis?

Neuroprotection is a difficult concept to define in the context of multiple sclerosis (MS), a complex heterogeneous disease with an uncertain immunopathogenetic mechanism. Although treatment and natural history studies use clinical determinants and MRI metrics to assess disability, long-term progression, and the effects of disease-modifying drugs, the association between clinical and imaging outcomes is relatively modest. In the future, a composite measure comprising both clinical and imaging markers, along with investigational surrogates derived from molecular genetics and proteomics, may provide an accurate quantitative measure of neuroprotection. However, a consensus definition of "neuroprotection" applicable to MS needs to be established before such a tool can be validated and put to use.