LAUSR

BACKGROUND The frequency and long-term prognosis of relapsing multiple sclerosis (RMS) never receiving disease-modifying treatment (DMT) is unclear. METHODS We included 1186 RMS patients with a mean of 17.4 years follow-up and divided them into patients treated with any DMT (DMT) and patients untreated by shared (USD) or patient-autonomous decision (UAD). RESULTS The USD group displayed features, which significantly differed from the two other groups: higher age at onset, mainly sensory onset symptoms, complete remission of onset symptoms, less T2 and contrast-enhancing T1 lesions on initial brain MRI. In a multivariate cox regression, USD was associated with lower risk for secondary progression (SPMS) conversion (hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.55-0.97, p = 0.011) compared to DMT, while UAD was associated with an increased SPMS conversion risk only in the "McDonald era" (HR 1.19, CI 1.02-1.58, p = 0.028). CONCLUSION Apart from the doubtless substantial improvement of the overall prognosis of RMS by DMT, it seems likely that not every patient necessarily needs immediate or even "hard and early" treatment. A "watchful waiting" approach with continuous clinical evaluation might be instead a viable option in RMS patients with favorable prognostic features at onset.