Vitamin D status of patients with systemic inflammatory connective tissue diseases: a cross-sectional study

Abstract

Background. In addition to regulating mineral metabolism and bone metabolism, vitamin D is important for supporting structure and other types of connective tissue. Studies have shown the role of vitamin D deficiency in the pathogenesis of systemic inflammatory diseases of the connective tissue, autoimmune diseases. The results of studying this problem in countries with different geographic locations are also of interest.Aim. Comparative assessment of vitamin D status of patients with systemic inflammatory diseases of the connective tissue and patients without rheumatic diseases.Materials and methods. This cross-sectional observational study analyzed the vitamin D supply of the following groups: patients with systemic inflammatory diseases of the connective tissue who do not take vitamin D preparations, patients with systemic inflammatory diseases of the connective tissue who take vitamin D preparations, and «conditionally healthy» individuals, without complaints, examined in the same period comparable in gender and age with the patients of the main group. The vitamin D supply of the studied patients was determined by the level of the content of the vitamin D metabolite calcidiol in the blood serum 25 (OH) D. Study period: January 2019 to December 2020.Results. The data of 625 patients who applied to the Osteoporosis Prevention and Treatment Center for the specified period were analyzed. Among the patients of the main group who did not take vitamin D preparations, a deficiency was revealed in 54.7% of the examined, the optimal provision in 11.2%. The median serum 25 (OH) D concentration was in the range of 19.0 ng / ml deficiency. The study participants belonging to the comparison group had a deficit in 44.1% of cases and an optimal provision in 21.5%. The study group of the main group receiving vitamin D preparations had the maximum number of individuals with the optimal status – 37.0%, while a significant part of the examined had a deficit of varying severity – 29.1%. In addition, this group was characterized by the highest median serum metabolite 25 (OH) D – 26.0 ng / ml.Conclusion. A comparative analysis of the D-vitamin status of patients with systemic inflammatory diseases of the connective tissue and «conditionally healthy» individuals without complaints was carried out, which made it possible to establish differences in the provision depending on the existing disease, as well as depending on the therapy with vitamin D preparations. a lower supply of vitamin D than control group «healthy» individuals. In the case of receiving vitamin subsidies, the provision with it in the group of patients was statistically significantly higher, both in comparison with patients who did not take the vitamin, and in comparison, with individuals from the comparison group.