title: Association of vitamin D with cardiometabolic risk factors in rheumatoid arthritis.
abstract: OBJECTIVE
  Individuals with rheumatoid arthritis (RA) are at a greater risk for cardiovascular disease (CVD). Vitamin D deficiency is a potential risk factor for CVD and metabolic syndrome. Since patients with RA have a high prevalence of vitamin D deficiency, we investigated the association of vitamin D levels with cardiometabolic risk factors in a cohort of RA patients with no prior history of CVD.
  
  
  METHODS
  Serum 25-hydroxyvitamin D (25[OH]D) levels were measured among RA patients enrolled in a cohort study of subclinical CVD. The cross-sectional associations of 25(OH)D levels with traditional CVD risk factors such as insulin resistance (IR; estimated using the homeostatic model assessment [HOMA]), adipokines, markers of systemic inflammation, and endothelial activation were explored, adjusting for pertinent sociodemographic, lifestyle, and RA characteristics.
  
  
  RESULTS
  Among 179 RA patients, 73 (41%) had a 25(OH)D level <30 ng/ml. Only 23 patients (13%) had a 25(OH)D level ≥45 ng/ml. After adjusting for demographics and body mass index (BMI), 25(OH)D remained significantly associated with high-density lipoprotein (HDL) cholesterol and inversely associated with HOMA-IR, fibrinogen, E-selectin, and soluble intercellular adhesion molecule 1 (sICAM-1). Significant associations with HDL cholesterol, E-selectin, and sICAM-1 were maintained after adjusting for the Disease Activity Score in 28 joints (DAS28) and autoantibody status. These associations were similar between the groups subdivided by sex, ethnicity, BMI, DAS28 level, and autoantibody status.
  
  
  CONCLUSIONS
  These data suggest that vitamin D deficiency is common in RA and may be independently associated with several cardiometabolic intermediates in this population.
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA. uhaque@jhmi.edu
authors.forename: Uzma J
authors.initials: UJ
authors.lastname: Haque
authors.forename: Joan M
authors.initials: JM
authors.lastname: Bathon
authors.forename: Jon T
authors.initials: JT
authors.lastname: Giles
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000150:complications; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008019:Life Style; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000150:complications; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012959:Socioeconomic Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications
chemical_list: D015415:Biomarkers; D014807:Vitamin D; C104450:25-hydroxyvitamin D