The long-term impact of early treatment of multiple sclerosis on the risk of disability pension

OBJECTIVE: The objective of this retrospective, observational study was to estimate the long-term impact of early treatment of multiple sclerosis (MS) on the risk of disability pension. METHODS: Our cohort comprised patients with MS in Sweden, identified in a nationwide disease-specific register (the Swedish Multiple Sclerosis Registry), who started treatment with a disease-modifying drug (DMD) between January 1, 2002, and December 31, 2012. We analyzed the association between time from onset of MS to treatment initiation and full-time disability pension using survival analysis. RESULTS: Our sample comprised 2477 patients. Unadjusted Kaplan–Meier failure functions showed that patients who started treatment within six months after onset had a lower risk of disability pension across follow-up compared with patients initiating therapy after 12 months. Outcomes from the univariate Cox proportional hazards model showed that time from onset to treatment initiation (in years) was significantly associated with disability pension (HR 1.03, p < 0.001). Outcomes from the multivariable Cox proportional hazards model showed that patients who started treatment within 6 months after onset had, on average, a 36% lower risk (HR 0.74, p = 0.010) of full-time disability pension during follow-up compared with patients starting treatment after 18 months when controlling for age, sex, marital status, university education, and prevalent comorbidities. CONCLUSIONS: We show that early treatment with DMDs of MS is associated with a significantly reduced risk of disability pension. Our findings highlight the potential long-term benefits of early treatment of MS and should be helpful to inform ongoing discussion on the optimum medical management of the disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00415-018-8764-4) contains supplementary material, which is available to authorized users.