title: Vitamin D may not be a good marker of disease activity in Korean patients with systemic lupus erythematosus.
abstract: Vitamin D is a pleiotrophic hormone with immunoregulatory properties. Low levels of vitamin D have been discovered in various autoimmune diseases. Here, we investigated serum vitamin D levels in Koreans with systemic lupus erythematosus (SLE) and examined whether levels correlate with disease activity of SLE. Blood samples were prospectively collected from patients with SLE (n = 104) and normal controls (NC, n = 49) during the spring from March to May 2008. The level of serum 25-hydroxyvitamin D (25(OH)D3) was measured by radioimmunoassay. The serum 25(OH)D3 levels of patients with SLE (42.49 ± 15.08 ng/ml) were significantly lower than NC (52.72 ± 15.19 ng/ml, P < 0.001). Additionally, 17 patients with SLE (16.3%) had vitamin D insufficiency, while two NC had vitamin D insufficiency (4.1%). The risk of vitamin D insufficiency was 4.6-fold increased in SLE (P = 0.032). The serum 25(OH)D3 levels, adjusted with BMI, were positively correlated only with hemoglobin (β = 0.256, P = 0.018) and serum complement 3 (β = 0.365, P = 0.002). Serum vitamin D levels were lower, and vitamin D insufficiency was more common in Korean patients with SLE, however, our study demonstrated that vitamin D levels might not be a good marker of disease activity.
authors.affiliation: Department of Allergy and Rheumatology, and BK21 Division of Cell Transformation and Restoration, Ajou University School of Medicine, Youngtong-gu, Suwon, 443-721, Korea.
authors.forename: Hyoun-Ah
authors.initials: HA
authors.lastname: Kim
authors.forename: Jun-Mo
authors.initials: JM
authors.lastname: Sung
authors.forename: Ja-Young
authors.initials: JY
authors.lastname: Jeon
authors.forename: Jeong-Moon
authors.initials: JM
authors.lastname: Yoon
authors.forename: Chang-Hee
authors.initials: CH
authors.lastname: Suh
mesh_terms: D000328:Adult; D044466:Asian People / Q000706:statistics & numerical data*; D015415:Biomarkers / Q000097:blood; D003176:Complement C3 / Q000032:analysis; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood*; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood
chemical_list: D015415:Biomarkers; D003176:Complement C3; D006454:Hemoglobins; D014807:Vitamin D