Methotrexate therapy for RA helps predict debilitating progressive joint damage

After 12 weeks of therapy with methotrexate (MTX), a simple model using the C-reactive protein (CRP) level and swollen joint count (SJC) may be useful in indicating week 52 radiographic progression in patients with rheumatoid arthritis (RA). Early identification of patients with an increased risk of debilitating progressive joint damage may be feasible.

Weinblatt and associates compared data collected after 12 weeks of MTX therapy for patients from the Trial of Etanercept and Methotrexate with Radiographic Patient Outcomes who showed the greatest and least disease progression at 52 weeks. They explored which combination of variables measured at 12 weeks correlated with radiographic progression at 52 weeks and used classification and regression tree modeling to predict best and worst radiographic outcomes.

Patients with the worst RA progression at 52 weeks had the highest joint count scores and levels of acute phase reactants at week 12. Those with a CRP level of 0.67 mg/dL or higher or an SJC of 10 or higher had the worst RA progression at week 52.

The authors noted that their findings allow for informed decisions about which patients may or may not need more aggressive treatment after a relatively short period of exposure to MTX.