Outcomes in a Modern Cohort of Treated Patients with Multiple Sclerosis from Diagnosis Up to 15 Years.

Background: Before disease-modifying therapies (DMTs) were available, the natural history of multiple sclerosis (MS) regarding attainment of accepted disability milestones was reported with fairly wide variance comparing outcomes across studies. The influence of DMTs on these outcomes is unknown. This study aimed to calculate attainment of disability milestones during the first 15 years after onset of DMT-treated relapsing forms of MS (RMS).

Methods: As a retrospective study, all available disability data (collected routinely) on all newly diagnosed patients with RMS seen and initially diagnosed in a single clinic between 1989 and 2006 were reviewed. Times from first symptoms and diagnosis until first treatment with DMTs were also reviewed. Time-to-event statistics were applied using disability milestones.

Results: Mean follow-up of 184 adult patients from symptom onset was 13.7 years. Of patients followed up for 15 years after onset, 16 of 86 (19%) reached an Expanded Disability Status Scale (EDSS) score of 6.0. Estimated median time to reach an EDSS score of 3.0 was 10.7 years and to reach an EDSS score of 4.0 was 18.1 years.

Conclusions: There were striking differences between the present results and older data sets and similar results to the few available modern data sets. This analysis of a modern treated RMS cohort provides outcomes data that may be compared favorably with the natural history of RMS.