Vitamin D Levels in Multiple Sclerosis and Subclinical Disease Activity

November 20, 2015

Low vitamin D levels are thought as a risk factor for the development of multiple sclerosis (MS). Multiple clinical trials are under way to determine whether vitamin D supplementation can reduce the severity of the disease. Researchers now report results of an analysis from the BEYOND study, a large clinical trial comparing Interferon to glatiramer acetate. Vitamin D samples were collected from 1796 trial participants at baseline, 6 months, and 12 months. Magnetic resonance imaging (MRI) was done at baseline and annually.

Patients with lower levels of vitamin D had more subclinical lesions on MRI. MRI T2 lesion volume and gadolinium-enhancing lesion numbers were each inversely correlated with baseline and 12-month, season-adjusted 25-hydroxyvitamin D levels (25[OH]D). The cumulative number of new active lesions between baseline and month 12 also correlated inversely with 25(OH)D level. During the two-year study, a 50 nmol/L higher level was associated with a 31% reduction in new lesions. Higher baseline 25(OH)D was associated with a lower score on the Expanded Disability Status Scale. No associations were found between 25(OH)D and brain volume at baseline, 12 months, or change from baseline through 24 months. No association was found for relapse rate.

This very large study, which recruited patients from around the world, provides strong epidemiologic evidence linking serum vitamin D level and MRI activity in MS. Pending completion of other Vit D clinical trials, it would be reasonable to offer vitamin D supplementation as a modest disease modifier. Patients can take Vit D3 with a common dose of 2000 to 5000 IU daily or 50,000 IU weekly.