title: Vitamin D deficiency in patients with active systemic lupus erythematosus.
abstract: We investigated the effects of disease activity on bone metabolism in 36 patients with systemic lupus erythematosus (SLE). Changes in bone remodeling were not explained by corticosteroid use. A high prevalence of 25OHD deficiency in SLE patients indicates the need for vitamin D replacement, mainly during high disease activity periods.
  
  
  BACKGROUND
  We investigated the effects of SLE disease activity on bone metabolism, their relation to inflammatory cytokines and vitamin D levels.
  
  
  METHODS
  We performed a cross-sectional analysis of 36 SLE patients classified according to the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) in high activity (group I: 12 patients, mean age 29.6 years) or in minimal activity (group II: 24 patients, mean age 30.0 years), and compared them to normal controls (group III: 26 women, 32.8 years). Serum calcium, phosphorus, parathyroid and sex hormones, bone remodeling markers, interleukin (IL)-6, soluble IL-6 receptor (sIL-6R), IL-1, tumor necrosis factor-alpha (TNF), 25-hydroxivitamin D (25OHD), and 1,25-dihydroxyvitamin D3 were measured, plus bone mineral density.
  
  
  RESULTS
  All cytokines were significantly higher in SLE groups; IL-6 could differentiate SLE patients from controls. In group I, 25OHD levels were lower (P < 0.05), which was related to the SLEDAI (R = -0.65, P < 0.001). In multiple regression analysis, the 25OHD level was associated with SLEDAI, osteocalcin and bone-specific alkaline phosphatase. The SLEDAI score was positively correlated with all measured cytokines and especially TNF (R = 0.75, P < 0.001).
  
  
  CONCLUSIONS
  SLE patients demonstrated changes in bone remodeling strongly related to disease activity. A high prevalence of 25OHD deficiency was observed in SLE patients, indicating the need for vitamin D replacement.
authors.affiliation: Division of Endocrinology, Universidade Federal de São Paulo, São Paulo, Brazil. familiabborba@terra.com.br
authors.forename: V Z C
authors.initials: VZ
authors.lastname: Borba
authors.forename: J G H
authors.initials: JG
authors.lastname: Vieira
authors.forename: T
authors.initials: T
authors.lastname: Kasamatsu
authors.forename: S C
authors.initials: SC
authors.lastname: Radominski
authors.forename: E I
authors.initials: EI
authors.lastname: Sato
authors.forename: M
authors.initials: M
authors.lastname: Lazaretti-Castro
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D016723:Bone Remodeling; D001938:Brazil; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000150:complications; D015675:Osteocalcin / Q000097:blood; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood*
chemical_list: D016207:Cytokines; D015675:Osteocalcin; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D000469:Alkaline Phosphatase