Efficacy of Cholecalciferol (Vitamin D3) for Delaying the Diagnosis of MS After a Clinically Isolated Syndrome

The secondary objectives of this study are: A. evaluate clinical efficacy: delay to conversion; number of relapses/episodes per year B. evaluate efficacy in terms of resonance imaging parameters (cerebral/spinal MRI) C. evaluate efficacy in terms of slowing the progression of disability as measured by EDSS score and subscores D. measure and assess cognitive abilities (PASAT) E. evaluate changes in quality of life (EQ5D questionnaires, SF36, and TLS-TLS-QoL10 COPING10), fatigue questionnaire (FSMC) and anxiety / depression questionnaire (HADS) F. evaluate treatment tolerance G. to correlate changes in clinical and imaging parameters with the evolution of serum levels of 25(OH)D2 and 25(OH)D3 H. establish a biobank of DNA and RNA from all patients in the study and conduct analyses of gene polymorphisms involved in the metabolism of vitamin D and the HLA system based on the increased levels of vitamin D after supplementation I. establish a biobank of CSF, plasma, blood cells, serum and RNA samples for patients in selected centers for research on prognostic biomarkers of conversion J. establish a biobank consisting of plasma tubes collected for the determination of 25-hydroxy-vitamin D K. Estimate the rate of discordance between the conversion decision made by the study neurologist and the result of the MRI re-interpretation performed at the end of the study as well as the proportion of patients identified a posteriori as as erroneously included according to the centralized reading.