Natural history of multiple sclerosis: long-term prognostic factors.

Several prognostic factors of long-term irreversible disability, mainly demographic and clinical, have been described in multiple sclerosis (MS). Most predictors have a minor influence on the long-term prognosis, and efforts are currently shifting toward finding relevant paraclinical predictors. By contrast, the study of prognostic factors has given some insights into the pathogenesis of MS, notably regarding the relation between relapses and long-term disability, and has emphasized the need to elucidate the exact mechanisms underlying neurodegeneration for the development of new therapeutic targets.