MS is characterized by two clinical phenomena: relapses and progression.
Progression may be evident from onset or after a relapsing-remitting phase. Progressive disease course refers to the accumulation of neurologic damage without any periods of relapse.
In a recent study of people with progressive MS, the authors explore factors that influence the rate of disability accumulation once patients enter the progressive phase. Specifically they looked at the effect of clinical relapses before or after onset of the progressive phase.
The researchers enrolled 101 people with progressive MS at Mayo Clinic, Minnesota, in 1992, 2002 and 2010. The study included only progressive patients with more than 20 years of follow-up.
The frequency of reported relapses that occurred after the onset of progressive MS was higher than expected. Only three per cent of patients with primary progressive MS had relapses after onset of the progressive phase, whereas 30 per cent of the patients with secondary progressive MS had relapses.
These findings suggest that patients with secondary progressive MS who have ongoing relapses may benefit from continuing immunomodulatory therapies after onset of progressive MS.
The study also suggests that immunomodulatory treatment is most likely to benefit patients who are under 55, or within five years of onset of progressive disease. Therefore, intervention to prevent post-progression relapses would be most effective in this period.
Overall, this study suggests tailoring treatment continuation or discontinuation decisions after progressive MS onset to the individual, as per the need.