Circulating Dickkopf-1 and Radiological Progression in Patients with Early Rheumatoid Arthritis Treated with Etanercept

Objective. Dickkopf-1 (Dkk-1) regulates bone remodeling in animal models of inflammatory arthritis, but its role in patients with rheumatoid arthritis (RA) remains unclear. Methods. Baseline circulating Dkk-1 was measured in 113 patients with RA (< 3 yrs) who received etanercept (10 or 25 mg twice/week, n = 63) or methotrexate alone (n = 40) for I year. Progression was assessed by changes in radiological Sharp score. Results. Increased Dkk-1 was associated with a higher risk of progression of bone erosion, independently of age, sex, baseline radiological damage, C-reactive protein, and disease activity in patients treated with etanercept. Conclusion. Dkk-1 may be an important mediator of bone erosion in patients with RA. (First Release Oct 1 2008; 1 Rheumatol 2008,35:2313-5; doi:10.3899/jrheum.080356)