Abstract
Objective To identify disease activity, smoking, and reproductive-related predictors of a poor prognosis in patients with very early inflammatory polyarthritis (IP).
Methods Patients with very early IP (symptom duration 4–11 weeks) included in our study were participants in the STIVEA (Steroids In Very Early Arthritis) randomized placebo-controlled trial. At baseline, disease-related variables were measured and patients were asked to complete a questionnaire covering smoking status and reproductive questions. Baseline predictors of poor prognosis [i.e., the need to start disease-modifying antirheumatic drug (DMARD) therapy by 6 months or the clinical diagnosis of rheumatoid arthritis (RA) at 12 months] were identified, applying logistic regression analyses adjusted for treatment group.
Results Rheumatoid factor (RF) positivity was one of the strongest clinical predictors of a poor prognosis: OR for DMARD therapy at 6 months, 4.00 (95% CI 2.00–8.00) and OR for a diagnosis of RA at 12 months, 9.48 (95% CI 4.48–20.07). There was a significant association between current smoking at baseline compared to never smoking and a diagnosis of RA at 12 months (OR 3.15, 95% CI 1.16–8.56).
Conclusion About 6 in 7 patients with very early RF-positive IP were diagnosed with RA 1 year later. In addition, 1 in 4 IP patients who smoke will develop RA later. It is recommended to treat RF-positive patients who have IP with DMARD at presentation and to advise patients to stop smoking.