title: Predictors of extra-articular manifestations in rheumatoid arthritis.
abstract: OBJECTIVE
  To identify clinical and genetic risk factors for extra-articular manifestations of rheumatoid arthritis (ExRA).
  
  
  METHODS
  ExRA patients were identified retrospectively using predefined criteria in two hospital-based cohorts of RA patients, and compared to non-extraarticular RA controls from one of the cohorts, matched for disease duration.
  
  
  RESULTS
  Forty-nine living and thirteen deceased cases of ExRA were identified. Extra-articular disease was predicted by the demonstration of antinuclear antibodies (Odds ratio (OR) 3.6; 95% CI: 1.4-9.1) and the presence of rheumatoid nodules within two years from RA diagnosis (OR 3.4; 95%, CI: 1.1-10.9) or at any time before ExRA onset (OR 2.8; 95% CI: 1.1-7.2). Male sex and rheumatoid factor did not affect the risk of ExRA. Although present in the majority of cases as well as controls, the disease associated HLA-DRB1 subtypes were not significant predictors of ExRA.
  
  
  CONCLUSIONS
  Extra-articular manifestations of rheumatoid arthritis in a hospital based population were predicted by antinuclear antibodies and rheumatoid nodules.
authors.affiliation: Department of Rheumatology, Malmö University Hospital, Sweden. Carl.Turesson@telia.com
authors.forename: C
authors.initials: C
authors.lastname: Turesson
authors.forename: L
authors.initials: L
authors.lastname: Jacobsson
authors.forename: U
authors.initials: U
authors.lastname: Bergström
authors.forename: L
authors.initials: L
authors.lastname: Truedsson
authors.forename: G
authors.initials: G
authors.lastname: Sturfelt
mesh_terms: D000293:Adolescent; D000328:Adult; D000974:Antibodies, Antinuclear / Q000032:analysis; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000276:immunology; D002648:Child; D015331:Cohort Studies; D005260:Female; D006684:HLA-DR Antigens / Q000032:analysis; D059811:HLA-DRB1 Chains; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012218:Rheumatoid Nodule / Q000209:etiology*
chemical_list: D000974:Antibodies, Antinuclear; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains