Increased Dickkopf-1 in Recent-onset Rheumatoid Arthritis is a New Biomarker of Structural Severity. Data from the ESPOIR Cohort

Rheumatoid arthritis (RA) is the most common chronic inflammatory rheumatic condition over the world. RA is potentially disabling because chronic inflammation of the joints leads to joint destruction. To date, the best predictor of radiographic progression for patients with early RA is the presence of radiographic erosions at baseline, but a limited number of predictive biomarkers of structural progression are currently used in daily practice. Here, we investigated Dickkopf-1 (DKK-1) and sclerostin (SOST) serum levels in patients with recent inflammatory arthritis from the ESPOIR cohort. This cohort is a prospective, multicenter French cohort of 813 patients with early arthritis. We observed that mean baseline DKK-1 level was higher among RA patients with than without radiological progression within the first 2 years of evolution. DKK-1 level was still associated with radiographic progression in a model including other main predictors of severity (erosions at baseline, and anti-CCP antibody positivity). This study demonstrates that increased DKK-1 level at baseline predicted structural progression after 2-year follow-up and suggests that DKK-1 might be a new structural biomarker for early RA.