Vitamin D Status in Patients with Systemic Lupus Erythematosus in Serbia: Correlation with Disease Activity and Clinical Manifestations

BACKGROUND Numerous studies indicate potential role of vitamin D as an important factor in the development of many autoimmune diseases including systemic lupus erythematosus (SLE). Patients with SLE are especially prone to the development of vitamin D deficiency due to the nature of their illness. AIM The aims of our study were to determine the prevalence of vitamin D insufficiency and deficiency in patients with SLE in Serbia, to identify clinical variables associated with vitamin D status and to examine the impact of vitamin D status on disease activity and presence of specific lupus autoantibodies. MATERIAL AND METHODS The study included 46 patients with SLE. Serum 25(OH)D concentration was measured by electrohemiluminiscent immunoassay. RESULTS The mean serum concentration of 25(OH)D was 11.9 ± 7.3 ng/ml. The prevalence of insufficiency was 32.6%, while the prevalence of deficiency was 67.4%. There was no association between vitamin D status and photosensitivity, skin lesions, arthritis and lupus nephritis. Vitamin D status was not associated with the presence of specific autoantibodies. There was no correlation between disease activity assessed by SLEDAI scale with the concentration of 25(OH)D. Patients who used vitamin D supplements and calcium did not have a significantly higher concentration of 25(OH)D. CONCLUSION In conclusion, vitamin D deficiency is common in patients with SLE.