A Randomized Controlled Trial of Vitamin D Supplementation in Multiple Sclerosis

PURPOSE: Low vitamin D levels have been shown to increase a person's risk of developing multiple sclerosis (MS), and patients with MS who have lower vitamin D levels are at increased risk of having attacks. However, it is not known if giving supplemental vitamin D to those with MS reduces the risk of attacks, and some research suggests that vitamin D could even be harmful to people with MS. In this clinical trial, patients with relapsing-remitting MS will receive high-dose or low-dose oral vitamin D in addition to an approved therapy for MS, glatiramer acetate. Patients will be evaluated for two years, and the effect of high-dose vitamin D supplementation on the rate of MS attacks and on the number of new lesions and change in brain volume on MRI will be determined. Establishing this association will have major implications for the treatment of individuals with MS throughout the world.