Abstract
ObjectiveTo compare the clinical utility of anti–cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor (RF) testing in predicting both functional outcome and response to treatment in early inflammatory polyarthritis (IP) patients.MethodsA total of 916 IP subjects from a primary care incidence registry (1990–1994) had anti-CCP antibody and RF status determined at baseline. Mean change in Health Assessment Questionnaire (HAQ) score between baseline and 5 years was compared by antibody status. The effect of treatment with disease-modifying antirheumatic drugs and/or steroids over 5 years, early (<6 months of symptom onset) versus late initiation, and duration of treatment were also compared by anti-CCP antibody status. The analysis was adjusted for treatment decisions and censoring over the followup, using marginal structural models.ResultsAnti-CCP antibody–positive patients (n = 268) had more severe disease both at presentation and 5 years of followup, and this was independent of RF. On adjustment, anti-CCP antibody–negative patients treated early experienced a significant improvement in functional disability compared with anti-CCP antibody–negative patients who were never treated (−0.31; 95% confidence interval [95% CI] −0.53, −0.08), and experienced additional benefit for each additional month of early treatment. Anti-CCP antibody–positive patients treated early did not have a significant improvement in HAQ score compared with those not treated (−0.14; 95% CI −0.52, 0.24).ConclusionIn this first observational study to examine the influence of anti-CCP antibody status on treatment response, anti-CCP antibody–positive IP patients showed less benefit from treatment, particularly early treatment, than anti-CCP antibody–negative patients. This provides support for the inclusion of anti-CCP antibodies as well as RF in the classification criteria for rheumatoid arthritis and for stratification by anti-CCP antibody status in clinical trials.
Highlights
In the past few years, the potential role of anti– cyclic citrullinated peptide antibodies has gained in-Supported by Arthritis Research UK.Address correspondence to Deborah P
AntiCCP antibody–negative patients experienced significant additional benefit for each additional month of early treatment (Ϫ0.13; 95% CI Ϫ0.22, Ϫ0.04), whereas anti-CCP antibody–positive patients did not (Ϫ0.05; 95% CI Ϫ0.18, 0.07). In this primary care– based inception cohort of patients with recent-onset inflammatory polyarthritis (IP), we found an association between the presence of anti-CCP antibodies at baseline and more severe disease both early in the disease and at 5 years of followup, and this association was independent of rheumatoid factor (RF)
We found that anti-CCP antibody– positive patients with IP showed less benefit from treatment, early treatment, than anti-CCP antibody–negative patients
Summary
To compare the clinical utility of anti– cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor (RF) testing in predicting both functional outcome and response to treatment in early inflammatory polyarthritis (IP) patients. Anti-CCP antibody–positive patients treated early did not have a significant improvement in HAQ score compared with those not treated (؊0.14; 95% CI ؊0.52, 0.24). In this first observational study to examine the influence of anti-CCP antibody status on treatment response, anti-CCP antibody–positive IP patients showed less benefit from treatment, early treatment, than anti-CCP antibody–negative patients. This provides support for the inclusion of anti-CCP antibodies as well as RF in the classification criteria for rheumatoid arthritis and for stratification by anti-CCP antibody status in clinical trials
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
