title: The predictive value of rheumatoid factor isotypes, anti-cyclic citrullinated peptide antibodies, and antineutrophil cytoplasmic antibodies for mortality in patients with rheumatoid arthritis.
abstract: OBJECTIVE
  To evaluate the significance of rheumatoid factor (RF) and its isotypes (IgA RF, IgG RF, and IgM RF), anti-cyclic citrullinated peptide antibodies (anti-CCP), and antineutrophil cytoplasmic antibodies (ANCA) in predicting mortality in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  The study population comprised 604 patients with RA participating in a cross-sectional study in 1987. Presence of RF (n = 604), RF isotypes (n = 206), anti-CCP (n = 184), and ANCA (n = 200) were determined in these patients from available baseline sera. Vital status was assessed in 1999 and multivariate Cox regression analysis used to compare mortality in RA patients with or without different antibodies.
  
  
  RESULTS
  Of the 604 patients with RA, 55% were positive for RF, 66% for anti-CCP, and 14.5% for perinuclear ANCA. Twelve patients (19%) with RF were anti-CCP-negative and 34 (40%) without RF were anti-CCP-positive. Of the total 604 patients, 160 had died by 1999. Positive RF and high IgA and IgM RF levels predicted increased mortality, while positive anti-CCP or ANCA did not. However, high anti-CCP levels were related to an increased mortality risk.
  
  
  CONCLUSIONS
  Patients with RA with positive RF, especially IgA and IgM isotypes, carry a risk of dying earlier than patients without these serological findings.
authors.affiliation: Department of Internal Medicine and Centre for Laboratory Medicine, Tampere University Hospital, University of Tampere Medical School, Tampere, Finland. susanna.sihvonen@fimnet.fi
authors.forename: Susanna
authors.initials: S
authors.lastname: Sihvonen
authors.forename: Markku
authors.initials: M
authors.lastname: Korpela
authors.forename: Anu
authors.initials: A
authors.lastname: Mustila
authors.forename: Jukka
authors.initials: J
authors.lastname: Mustonen
mesh_terms: D000368:Aged; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000276:immunology* / Q000401:mortality*; D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D011237:Predictive Value of Tests; D012217:Rheumatoid Factor / Q000097:blood*; D012307:Risk Factors; D012720:Severity of Illness Index; D016019:Survival Analysis
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D015415:Biomarkers; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor