To study the predictive value of anticyclic citrullinated peptide antibody (anti-CCP) in patients with recent-onset rheumatoid arthritis (RA).
Outcome in terms of physical disability (Health Assessment Questionnaire) and radiologic damage (modified Sharp method) over 3-year and 6-year periods was determined in an inception cohort of 273 RA patients who had had disease symptoms for <1 year at study entry. Anti-CCP titers were determined at baseline and considered positive as recently described. Their prognostic value was studied by means of multiple regression analysis, in which anti-CCP positivity, sex, age at study entry, IgM rheumatoid factor (IgM-RF) status, Disease Activity Score (DAS), HLA-DR4 status, and (in a separate group of patients) shared epitope status were used as independent variables, and radiologic damage and functional disability as dependent variables.
Patients with anti-CCP had developed significantly more severe radiologic damage after 6 years of followup. In multiple regression analysis, radiologic damage after 6 years followup was significantly predicted by IgM-RF status, radiologic score at entry, and anti-CCP status. Functional disability was significantly predicted by sex, age at entry, IgM-RF status, and DAS.
Our data show that in almost 70% of RA patients, anti-CCP antibody is present at the early stages of disease. Anti-CCP-positive patients developed significantly more severe radiologic damage than patients who were anti-CCP negative, although in multiple regression analysis the additional predictive value was rather moderate.