title: Vitamin D Is a Good Marker for Disease Activity of Rheumatoid Arthritis Disease.
abstract: OBJECTIVE
  This study was conducted to find out the optimal vitamin D cutoff point in predicting activity of RA disease.
  
  
  METHODS
  One hundred and two rheumatoid arthritis Saudi patients of both genders were recruited in this study. Vitamin D as 25-hydroxy-vitamin D [25(OH)D] was measured and serum level less than 20 ng/mL defined as deficient patient. Disease activity was measured based on the disease activity score index of a 28-joint count (DAS28) using serum erythrocyte sedimentation rate levels. Receiver operating characteristic (ROC) curves were used to determine the optimal vitamin D cutoff points for identifying disease activity.
  
  
  RESULTS
  It has been observed that vitamin D levels were lower (P < 0.05) in patients with high disease activity. A significant inverse correlation between serum 25(OH)D levels and DAS28 (r = -0.277, P = 0.014) was shown. ROC curves results showed that vitamin D less than 12.3 ng/mL predicted high disease activity, and vitamin D more than 17.9 ng/mL predicted low disease activity, with good sensitivity and accuracy results regarding vitamin D.
  
  
  CONCLUSIONS
  Study results concluded that vitamin D is a good predictor of RA disease activity in Saudi patients.
authors.affiliation: Department of Clinical Nutrition, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah 21955, Saudi Arabia.
authors.forename: Firas Sultan
authors.initials: FS
authors.lastname: Azzeh
authors.affiliation: Department of Clinical Nutrition, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah 21955, Saudi Arabia.
authors.forename: Osama Adnan
authors.initials: OA
authors.lastname: Kensara
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002112:Calcifediol / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers; D002112:Calcifediol