Impact of diagnosis and early treatment on the course of multiple sclerosis.

Multiple sclerosis (MS) is a progressive inflammatory disease of the central nervous system that results in neurological dysfunction and disability. The initiation of disease-modifying therapy (DMT) early in the course of MS may improve the prognosis for patients with MS and reduce the occurrence of neurological damage. In patients with relapsing-remitting MS (RRMS), DMT reduces the rate of relapses, reduces the appearance of magnetic resonance imaging markers of disease activity, and slows the course of disability progression. DMT has been shown to be more effective when initiated early in the course of MS. In patients who have not yet developed clinically definite MS (CDMS), but have had 1 attack of neurological symptoms consistent with MS (ie, clinically isolated syndrome [CIS]), the initiation of DMT (specifically, interferon beta, glatiramer acetate, and teriflunomide) following this attack has been shown to delay the conversion to CDMS. Current guidelines have recognized the benefits of early treatment of MS with DMTs. However, there are a number of barriers to implementing early MS treatment. Early diagnosis and treatment of MS can be hindered because patients may delay consulting a physician about their neurological symptoms or may be reluctant to start DMT. Further, even after initiating DMT, continued adherence to treatment is often poor. These delays in treatment and a lack of adherence to treatment are associated with poor patient outcomes. The objectives of this review are to highlight the importance of early diagnosis and treatment of CIS or RRMS and discuss the favorable outcomes associated with early initiation of DMT.