title: Levels of markers of bone resorption are moderately increased in patients with inactive rheumatoid arthritis.
abstract: OBJECTIVE
  Clinical remission occurs in 10-20% of patients with rheumatoid arthritis (RA). However, it is questionable whether clinical remission corresponds to the complete absence of the inflammatory process. To answer this question we measured collagen degradation products (which are known to be increased in active disease) in patients with inactive RA and in healthy controls.
  
  
  METHODS
  The urinary levels of bone resorption markers (pyridinoline, deoxypyridinoline, N-terminal telopeptide and C-terminal telopeptide) were measured in 184 patients with inactive RA, as defined by the preliminary criteria of clinical remission of the American College of Rheumatology, and in 118 healthy individuals.
  
  
  RESULTS
  After adjusting for age, concentrations of all four bone resorption markers were found to be significantly higher in patients with inactive RA than in healthy controls.
  
  
  CONCLUSIONS
  The urinary excretion of bone resorption markers is increased in patients classified as having inactive RA. These results suggest that the inflammatory process is not completely absent.
authors.affiliation: Department of Rheumatology, University Hospital Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: E T
authors.initials: ET
authors.lastname: Molenaar
authors.forename: W F
authors.initials: WF
authors.lastname: Lems
authors.forename: B A
authors.initials: BA
authors.lastname: Dijkmans
authors.forename: M H
authors.initials: MH
authors.lastname: de Koning
authors.forename: R J
authors.initials: RJ
authors.lastname: van de Stadt
authors.forename: A E
authors.initials: AE
authors.lastname: Voskuyl
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000652:urine*; D001172:Arthritis, Rheumatoid / Q000628:therapy / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D001862:Bone Resorption / Q000652:urine*; D001842:Bone and Bones / Q000378:metabolism*; D003094:Collagen / Q000652:urine; D024042:Collagen Type I; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000652:urine; D012074:Remission Induction
chemical_list: D000596:Amino Acids; D015415:Biomarkers; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; C015484:pyridinoline; C036020:deoxypyridinoline; D003094:Collagen