Discontinuation of disease-modifying treatments for multiple sclerosis in patients aged over 50 with disease Inactivity.

Background: Treatments may become redundant in older patients with multiple sclerosis (MS). Our aim was to explore whether stopping treatments might be possible in patients aged over 50 with disease inactivity.

Methods: Patients over 50 were included from the population-based MS Lorraine registry if they had a relapsing-remitting course at onset and had experienced no relapse for ≥ 3 years. Patients who stopped treatments were defined as "stoppers", and the others as "stayers". The outcomes were the time to first relapse, to first disability progression, and to the occurrence of EDSS score of 6, assessed by multivariate analysis using a propensity score.

Results: 132 stoppers and 366 stayers had a median follow-up of 7 years. There was no difference in Log-rank tests for the times to first relapse (p = 0.61) and to first disability progression (p = 0.22). In Cox models, stopping treatments was not associated with an increased risk of relapse (adjusted Hazard ratio (aHR) = 0.92 [0.72-1.16; p = 0.47]) or of an increase in EDSS score (aHR = 0.89 [0.71-1.13; p = 0.34]). However, stopping was associated with a higher risk of occurrence of EDSS score of 6 (aHR = 3.29 [2.22-4.86; p < 0.0001]), with a significant difference for the time to occurrence of EDSS score of 6 (p = 0.003).

Conclusion: Our study suggests that stopping injectable disease-modifying treatments, in patients over 50 with disease inactivity, is not associated with an increased risk of relapse or EDSS progression, but there might be a higher risk of reaching EDSS 6. These results have to be confirmed by interventional studies.