Benign multiple sclerosis: Factors associated with and long-term outcome.

 Benign multiple sclerosis is often defined by EDSS score of ≤3.0 after 15 or more years of disease duration.

2420 benign cases were identified in the Swedish Multiple Sclerosis registry

Benign patients were more likely to be

• female
• younger at MS onset,
• have fewer relapses within the first 2 & 5 years from onset and
• fully recover from the first relapse
• Lack of an association with major HLA region suggesting that MS course is most likely influenced by either environmental factor(s) or genetic factors outside the HLA region.

In this Swedish cohort, 12% and 6% of total MS patients still had EDSS score ≤3.0 after 20 and 25 years from MS onset, respectively.