Mark S. Stein, PhD, of Royal Melbourne Hospital, and colleagues performed a six-month randomized, controlled trial that included 23 patients with relapsing-remitting MS. Eleven patients were randomized to receive a high dose of vitamin D2 (6,000 IU), which was intended to elevate their serum 25-hydroxyvitamin D (250HD) to a level of 130 to 175 nM, while 12 patients were randomized to receive a placebo in place of the high dose. In addition, all patients received low doses of vitamin D2 (1,000 IU) to prevent deficiency.
During the follow-up period, patients underwent brain MRI and biochemical and clinical monitoring. The study’s primary end points were the cumulative number of new gadolinium-enhancing lesions and change in total volume of T2 lesions. Its secondary end points were scores on the Expanded Disability Status Scale (EDSS) and relapses.
After six months, the high-dose and low-dose groups did not differ significantly with regard to the development of new lesions or changes in the total volume of T2 lesions. Four patients who were in the high-dose group and two patients in the low-dose group developed new lesions, with totals of 14 new lesions in the high-dose group and 11 new lesions in the low-dose group. Patients in the high-dose group lost a median of 330 mm3 in lesion volume, and patients in the low-dose group lost a median of 95 mm3 of lesion volume.
Exit scores on the EDSS, after adjustment for entry scores on the scale, were marginally higher in the high-dose group than in the low-dose group. The median scores were 3 and 2 in the high-dose and low-dose groups, respectively. Four (36.5%) patients in the high-dose group and no patients in the low-dose group had a relapse.
It is possible that “any vitamin D benefit for MS occurs with low-level supplementation and oral vitamin D beyond that does not provide additional benefit,” the investigators speculated. “If this is the case, then epidemiologic correlations of better MS outcomes with higher serum 250HD may simply reflect the identification of people with MS who have a low probability of experiencing vitamin D deficiency.
Stein MS, Liu Y, Gray OM, et al. A randomized trial of high-dose vitamin D2 in relapsing-remitting multiple sclerosis. Neurology. 2011;77(17):1611-1618.