title: Anti-CCP antibody and rheumatoid factor concentrations predict greater disease activity in men with rheumatoid arthritis.
abstract: OBJECTIVE
  To examine associations of anti-cyclic citrullinated peptide (aCCP) antibody and rheumatoid factor (RF) concentrations with future disease activity in men with rheumatoid arthritis (RA).
  
  
  METHODS
  Outcome measures were examined in male US veterans with RA and included (1) proportion of observations in remission (disease activity score (DAS28) < or =2.6); (2) remission for > or =3 consecutive months; and (3) area under the curve (AUC) for DAS28. The associations of autoantibody concentration (per 100 unit increments) with outcomes were examined using multivariate regression.
  
  
  RESULTS
  826 men with RA were included in the analysis; the mean (SD) age was 65 (10.5) years and follow-up was for 2.6 (1.3) years. Most were aCCP (75%) and RF (80%) positive. After multivariate adjustment, aCCP (OR 0.93; 95% CI 0.89 to 0.96) and RF concentrations (OR 0.92; 95% CI 0.90 to 0.94) were associated with a lower odds of remission, a lower proportion of observation in remission (p=0.017 and p=0.002, respectively) and greater AUC DAS28 (p=0.092 and p=0.007, respectively). Among patients with discordant autoantibody status, higher concentrations of both aCCP and RF trended towards an inverse association with remission (OR 0.93; 95% CI 0.83 to 1.05 and OR 0.80; 95% CI 0.59 to 1.10, respectively).
  
  
  CONCLUSIONS
  Higher aCCP concentrations (particularly in RF-positive patients) are associated with increased disease activity in US veterans with RA, indicating that aCCP concentration is predictive of future disease outcomes in men.
authors.affiliation: Department of Internal Medicine, Section of Rheumatology and Immunology, 986270 Nebraska Medical Center, Omaha, NE 68198-6270, USA.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Miriovsky
authors.forename: Kaleb
authors.initials: K
authors.lastname: Michaud
authors.forename: Geoffrey M
authors.initials: GM
authors.lastname: Thiele
authors.forename: James R
authors.initials: JR
authors.lastname: O'Dell
authors.forename: Grant W
authors.initials: GW
authors.lastname: Cannon
authors.forename: Gail
authors.initials: G
authors.lastname: Kerr
authors.forename: J Steuart
authors.initials: JS
authors.lastname: Richards
authors.forename: Dannette
authors.initials: D
authors.lastname: Johnson
authors.forename: Liron
authors.initials: L
authors.lastname: Caplan
authors.forename: Andreas
authors.initials: A
authors.lastname: Reimold
authors.forename: Roderick
authors.initials: R
authors.lastname: Hooker
authors.forename: Ted R
authors.initials: TR
authors.lastname: Mikuls
mesh_terms: D000368:Aged; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D010456:Peptides, Cyclic / Q000276:immunology*; D011379:Prognosis; D012074:Remission Induction; D012217:Rheumatoid Factor / Q000097:blood*; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D018501:Antirheumatic Agents; D001323:Autoantibodies; D015415:Biomarkers; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor