The influence of immunomodulatory treatment on the clinical course of multiple sclerosis.

Background: Multiple sclerosis (MS) is a chronic disease of the central nervous system. One of the major questions concerning the clinical progression of MS, still insufficiently elaborated or confirmed, is if it can be slowed down or augmented by external factors. Immunomodulatory treatment is a disease modifiable factor shown to influence disease progression of various medical conditions.
Objective: To investigate if treatment affects the long-term clinical progression of MS, measured as time from diagnosis to score of 4 or higher of Expanded Disability Status Scale (EDSS).
Methods: Longitudinal, prospective data concerning treatment status and EDSS were collected by health professionals in the Swedish MS Registry. Study cohort comprised new diagnosed MS patients at Karolinska Hospital between 2001 and 2005. Survival analysis adjusted for suspected confounders was used with the outcome variable time from diagnosis to EDSS ≥ 4.
Results: Early treatment was correlated with longer time from diagnosis to EDSS ≥ 4 (HR: 1.77; 95 % CI: 1.15-2.73; p = 0.01). Additionally, the influence of the covariates-age at onset and the baseline EDSS, which were statistically significant with hazard ratios of 1.03 and 2.1, respectively, was found.
Conclusion: Early treatment was associated with a better clinical outcome.