Robert T. Naismith, MD reviewing Sotirchos ES et al. Neurology 2015 Dec 30.

In vitro immunologic effects with potential benefit were seen with high daily supplementation in a pilot trial.

Vitamin D has a multitude of biological effects, including an impact on the immune system. Studies have shown an increased risk to develop multiple sclerosis (MS) in those who have low vitamin D levels and increased numbers of brain lesions on imaging for those with low serum levels after diagnosis (NEJM JW Neurol Dec 2015 and JAMA Neurol 2015; 72:1458).

In this single-center study, researchers randomized 40 patients with MS to 800 IU (low dose) or 10,400 IU (high dose) of cholecalciferol daily for 6 months. Patients with severe vitamin D deficiency were excluded (<20 ng/mL). Serum vitamin D increased from baseline by 34.9 ng/mL in the high-dose arm and by 6.9 ng/mL in the low-dose arm. One relapse occurred in each arm. The percentages of IL17+CD4+ T cells and effector memory CD4+ cells were reduced from baseline in the high-dose arm, but not in the low-dose arm. Central memory CD4+ cells and naive CD4+ cells were increased in the high-dose arm. Three patients (2 of them in the high-dose group) discontinued treatment because of nausea.

Citation(s):

Sotirchos ES et al. Safety and immunologic effects of high- vs low-dose cholecalciferol in multiple sclerosis. Neurology 2015 Dec 30; [e-pub].

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