Objective: Rheumatoid arthritis is characterized by antibodies to citrullinated proteins (ACPA) and rheumatoid factor (RF) in the preclinical phase. Therefore, an intervention aimed at decreasing autoantibody levels in persons at risk may be effective in preventing progression to arthritis.
Methods: 83 arthralgia patients positive for ACPA or IgM-RF were randomly allocated to intramuscular injections of 100 mg dexamethasone or placebo at t=0 and 6 weeks. The primary endpoint was a 50% antibody reduction or normalization at 6 months.
Results: The primary endpoint was reached in one patient in each group. Patients treated with dexamethasone had reductions of antibody levels after 1 month (ACPA -22% and IgM-RF -14%), which persisted at 6 months for ACPA. During a median follow-up of 26 months, arthritis development in both groups was similar (20 vs. 22%).
Conclusion: In autoantibody positive arthralgia patients, dexamethasone treatment decreases ACPA and IgM-RF levels, but does not prevent arthritis development.