Multiple Sclerosis Patients Show Differences in Vitamin D Binding Protein and Calcium Compared to Controls.

Background: Previous studies have found an association between vitamin D and MS but the basis for this relationship is not well understood. This relationship is also supported by the finding that MS subjects show an increase in osteoporosis/osteopenia, however this may be related to steroid use and decreased activity levels. A recent study in cattle identified the CYP2J2 gene as playing a major role in the vitamin D pathway to producing active 1,25-dihydroxyvitamin D. The endocrine physiology of vitamin D in cattle and humans is similar and the chromosome regions containing CYP2J2 are syntenic, making the research in humans a reasonable extension of study. The known propensity of low vitamin D levels in MS patients, the expression of prolactin in activated T-cells and the clinical experience of the researcher in regards to higher circulating prolactin levels and progression of MS in select patients led to the selection of vitamin D, vitamin D binding protein, calcium and prolactin serum levels as markers.

Objectives: To evaluate association of vitamin D, vitamin D binding protein, calcium and prolactin with MS status.

Methods: Blood was drawn from all participants giving informed consent with both affected and non-affected subjects included. The serum was separated and then tested at fee-for-service laboratories for levels of vitamin D, vitamin D binding protein, calcium and prolactin. All serum markers were compared using both parametric (t-tests) and nonparametric statistical tests (Mann-Whitney U Test, median test).

Results: Serum levels of vitamin D, vitamin D binding protein and calcium were significantly different between MS patients and healthy controls. Vitamin D and vitamin D binding protein were both significantly higher in MS patients than in controls while calcium levels were significantly lower in MS patients than controls, regardless of supplementation.  Vitamin D levels were likely skewed related to standard of care administration of vitamin D supplementation and further analysis will be done at a later date. However, higher vitamin D due to supplementation did not translate into higher calcium levels in MS patients even though vitamin D plays a role in calcium absorption.  Prolactin levels were not significantly different in MS patients and controls.

Conclusions: Calcium levels were significantly lower in MS patients than controls.  Further, calcium levels were not related to vitamin D, vitamin D binding protein or prolactin levels. This study suggests that calcium metabolism may altered in MS patients.  Further research is needed to determine the nature of this alteration.