Vitamin D Status Among Children With Juvenile Idiopathic Arthritis: A Multicenter Prospective, Non-randomized, Comparative Study.

Background: Juvenile idiopathic arthritis (JIA) is a chronic autoimmune disease characterized by destructive and inflammatory damage to the joints. The aim in this study was to compare vitamin D levels between children and adolescents, 1-18 years of age, with juvenile idiopathic arthritis (JIA) and a health control group of peers. We considered effects of endogenous, exogenous, and genetic factors on measured differences in vitamin D levels among children with JIA.

Vitamin D Status in Russian Children and Adolescents: Contribution of Genetic and Exogenous Factors.

The problem of vitamin D deficiency is particularly relevant for the entire territory of Russia, since most parts of the country are located above the 42nd geographical latitude and the residents are therefore at risk of vitamin D deficiency. Despite the urgency of the problem, a comprehensive study of the molecular and genetic mechanisms and exogenous factors of vitamin D deficiency in children living in various geographical areas of the Russian Federation has not been conducted. Different variants in the loci of the genes responsible for the synthesis, hydroxylation, and transport of vitamin D (such as , and ), as well as gene polymorphisms may also be associated with the risk of vitamin D deficiency.