Vitamin D deficiency linked to higher disease activity in JIA
Among patients with juvenile idiopathic arthritis, vitamin D deficiency is associated with higher disease activity, as well as an increased risk for anterior uveitis, according to data published in Arthritis Research & Therapy.
“Several studies have shown an association between low vitamin D, mostly measured as 25(OH)vitamin D3 (25(OH)D), and higher incidence and severity of autoimmune disorders, such as type 1 diabetes mellitus, chronic inflammatory bowel disease, rheumatoid arthritis and multiple sclerosis,” Claudia Sengler, MD, of the German Rheumatism Research Center, and colleagues wrote. “Currently, the measurement of 25(OH)D is considered standard because it is stable and reflects the vitamin D provision of the last weeks to months.”
To analyze the levels of 25(OH)D in patients with JIA, and to determine whether they affect disease activity, Sengler and colleagues studied patients aged 16years and younger with recently diagnosed JIA, who were enrolled in the ICON cohort of patients with newly diagnosed JIA. According to the researchers, ICON is an ongoing prospective observational, controlled multicenter study that began in 2010. In this study, the researchers examined clinical and laboratory parameters quarterly during the first year, and then half-yearly thereafter.
Among the 954 patients with JIA enrolled in the study, Sengler and colleagues focused on 360 who had two blood samples taken during the first 2years after inclusion, with a follow up of 3 years. Serum 25(OH)D levels were determined and compared with those of subjects from the general population, matched for age, sex, migration status and the month of blood-drawing.
According to the researchers, 44% of patients with JIA were vitamin D deficient, defined as having less than 20 ng/ml of 25(OH)D. However, vitamin D deficiency was even more common, at 62%, among the healthy control group. Disease activity (beta = –0.2; 95% CI, –0.37 to 0.03) and the risk for JIA-associated anterior uveitis (HR = 0.95; 95% CI, 0.91-0.9) were inversely correlated with the 25(OH)D level.
“Our study revealed that vitamin D deficiency is common in patients with JIA, although the prevalence was lower than in matched subjects from the general population,” Sengler and colleagues wrote. “In patients with JIA, vitamin D deficiency is associated with higher disease activity and a higher risk of developing uveitis and possibly the extended form of oligoarthritis. ... To further clarify if cholecalciferol substitution in order to achieve a sufficient 25(OH)D level might have the potential to prevent the development of uveitis and the extended form of oligoarthritis, these associations must be confirmed by an interventional study.” – by Jason Laday
Disclosure: Sengler reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.