title: Osteoprotegerin/RANKL axis and progression of coronary artery calcification in hemodialysis patients.
abstract: OBJECTIVE
  Vascular calcification is associated with increased cardiovascular mortality in chronic hemodialysis patients. This prospective study investigated the relationship between serum osteoprotegerin, receptor activator of NF-κB ligand, inflammatory markers, and progression of coronary artery calcification score.
  
  
  METHODS
  Seventy-eight hemodialysis patients were enrolled. Serum IL-1β, IL-6, TNF-α, osteoprotegerin, receptor activator of NF-κB, fetuin A, and bone alkaline phosphatase were measured by ELISA. Coronary artery calcification score was measured two times with 1-year intervals, and patients were classified as progressive or nonprogressive.
  
  
  RESULTS
  Baseline and first-year serum osteoprotegerin levels were significantly higher in the progressive than nonprogressive group (17.39±9.67 versus 12.90±6.59 pmol/L, P=0.02; 35.17±18.35 versus 24±11.65 pmol/L, P=0.002, respectively). The ratio of serum osteoprotegerin to receptor activator of NF-κB ligand at 1 year was significantly higher in the progressive group (0.26 [0.15-0.46] versus 0.18 [0.12-0.28], P=0.004). Serum osteoprotegerin levels were significantly correlated with coronary artery calcification score at both baseline (r=0.36, P=0.001) and 1 year (r=0.36, P=0.001). Importantly, progression in coronary artery calcification score significantly correlated with change in serum osteoprotegerin levels (r=0.39, P=0.001). In addition, serum receptor activator of NF-κB ligand levels were significantly inversely correlated with coronary artery calcification scores at both baseline (r=-0.29, P=0.01) and 1 year (r=-0.29, P=0.001). In linear regression analysis for predicting coronary artery calcification score progression, only baseline coronary artery calcification score and change in osteoprotegerin were retained as significant factors in the model.
  
  
  CONCLUSIONS
  Baseline coronary artery calcification score and serum osteoprotegerin levels were significantly associated with progression of coronary artery calcification score in hemodialysis patients.
authors.affiliation: Istanbul Faculty of Medicine, Department of Internal Medicine and Nephrology, Istanbul University, Istanbul, Turkey.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Ozkok
authors.forename: Yasar
authors.initials: Y
authors.lastname: Caliskan
authors.forename: Tamer
authors.initials: T
authors.lastname: Sakaci
authors.forename: Gaye
authors.initials: G
authors.lastname: Erten
authors.forename: Gonca
authors.initials: G
authors.lastname: Karahan
authors.forename: Alper
authors.initials: A
authors.lastname: Ozel
authors.forename: Abdulkadir
authors.initials: A
authors.lastname: Unsal
authors.forename: Alaattin
authors.initials: A
authors.lastname: Yildiz
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D002908:Chronic Disease; D003324:Coronary Artery Disease / Q000097:blood / Q000209:etiology*; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood; D007674:Kidney Diseases / Q000097:blood / Q000150:complications / Q000628:therapy*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D053244:Osteoprotegerin / Q000097:blood*; D011446:Prospective Studies; D053245:RANK Ligand / Q000097:blood*; D006435:Renal Dialysis / Q000009:adverse effects*; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014421:Turkey; D061205:Vascular Calcification / Q000097:blood / Q000209:etiology*
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D053244:Osteoprotegerin; D053245:RANK Ligand; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human