title: Predictive value of autoantibody testing for validating self-reported diagnoses of rheumatoid arthritis in the Women's Health Initiative.
abstract: Rheumatoid arthritis (RA) research using large databases is limited by insufficient case validity. Of 161,808 postmenopausal women in the Women's Health Initiative, 15,691 (10.2%) reported having RA, far higher than the expected 1% population prevalence. Since chart review for confirmation of an RA diagnosis is impractical in large cohort studies, the current study (2009-2011) tested the ability of baseline serum measurements of rheumatoid factor and anti-cyclic citrullinated peptide antibodies, second-generation assay (anti-CCP2), to identify physician-validated RA among the chart-review study participants with self-reported RA (n = 286). Anti-CCP2 positivity had the highest positive predictive value (PPV) (80.0%), and rheumatoid factor positivity the lowest (44.6%). Together, use of disease-modifying antirheumatic drugs and anti-CCP2 positivity increased PPV to 100% but excluded all seronegative cases (approximately 15% of all RA cases). Case definitions inclusive of seronegative cases had PPVs between 59.6% and 63.6%. False-negative results were minimized in these test definitions, as evidenced by negative predictive values of approximately 90%. Serological measurements, particularly measurement of anti-CCP2, improved the test characteristics of RA case definitions in the Women's Health Initiative.
authors.forename: Brian
authors.initials: B
authors.lastname: Walitt
authors.forename: Rachel
authors.initials: R
authors.lastname: Mackey
authors.forename: Lewis
authors.initials: L
authors.lastname: Kuller
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Deane
authors.forename: William
authors.initials: W
authors.lastname: Robinson
authors.forename: V Michael
authors.initials: VM
authors.lastname: Holers
authors.forename: Yue-Fang
authors.initials: YF
authors.lastname: Chang
authors.forename: Larry
authors.initials: L
authors.lastname: Moreland
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000097:blood / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D001323:Autoantibodies / Q000097:blood; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000097:blood / Q000276:immunology; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012217:Rheumatoid Factor / Q000097:blood* / Q000276:immunology; D057566:Self Report; D016387:Women's Health
chemical_list: D000888:Antibodies, Anti-Idiotypic; D001323:Autoantibodies; D015415:Biomarkers; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor
keywords: anti-cyclic citrullinated peptide antibody; diagnostic validation; rheumatoid arthritis; rheumatoid factor