Assessment of Biochemical and Densitometric Markers of Calcium-Phosphate Metabolism in the Groups of Patients with Multiple Sclerosis Selected due to the Serum Level of Vitamin D 3 .

Background: In addition to the widely known effect of vitamin D3 (vitD3 ) on the skeleton, its role in the regulation of the immune response was also confirmed.

Aim: The assessment of biochemical and densitometric markers of calcium-phosphate metabolism in the groups of patients with relapsing-remitting multiple sclerosis (RRMS) selected due to the serum level of vitamin D3 .

Methods: The concentrations of biochemical markers and indices of lumbar spine bone densitometry (DXA) were determined in 82 patients divided into vitamin D3 deficiency (VitDd), insufficiency (VitDi), and normal vitamin D3 level (VitDn) subgroups.

Results: The highest level of the parathyroid hormone (PTH) and the highest prevalence of hypophosphatemia and osteopenia were demonstrated in VitDd group compared to VitDi and VitDn. However, in VitDd, VitDi, and VitDn subgroups no significant differences were observed in the levels of alkaline phosphatase (ALP) and ionized calcium (Ca2+ ) and in DXA indices. A negative correlation was observed between the level of vitamin D3 and the Expanded Disability Status Scale (EDSS) in the whole MS group. The subgroups were significantly different with respect to the EDSS scores and the frequency of complaints related to walking according to the EQ-5D.

Conclusions: It is necessary to assess calcium-phosphate metabolism and supplementation of vitamin D3 in RRMS patients. The higher the clinical stage of the disease assessed with the EDSS, the lower the level of vitamin D3 in blood serum. Subjectively reported complaints related to difficulties with walking were reflected in the EDSS in VitDd patients.