In patients with early rheumatoid arthritis (eRA), low baseline C-reactive protein (CRP) and leptin, as well as high tumor necrosis factor receptor 1 (TNF-R1) and vascular cell adhesion molecule 1 (VCAM-1) were associated with low disease activity (LDA) after 3 months of methotrexate (MTX) therapy, according to study results published in The Journal of Rheumatology.
The study included participants with eRA from the Swedish Pharmacotherapy clinical trial (n=298). The researchers analyzed baseline serum levels of 12 proteins to determine whether they were associated with disease activity after 3 months of MTX monotherapy. Disease activity was measured with the 28-joint count Disease Activity Score (DAS28). The primary outcome was LDA (DAS28 ≤3.2).
After 3 months on MTX, 104 participants achieved LDA.
After stepwise logistic regression analysis, 4 biomarkers (CRP, leptin, TNF-R1 and VCAM-1) significantly predicted LDA.
The researchers dichotomized participants using receiver-operating characteristic curve analysis-based cutoffs. They found a significantly higher percentage of LDA in participants with lower compared with higher CRP or leptin levels (40% vs 23%; P =.004, and 40% vs 25%; P =.011, respectively). They also found a significantly higher percentage of LDA in participants with higher compared with lower TNF-RI or VCAM-1 levels (43% vs 27%; P =.004, and 41% vs 25%; P =.004, respectively).
“If validated, these biomarkers could become a useful complement when choosing the treatment strategy for patients with eRA,” the researchers wrote.
Hambardzumyan K, Bolce RJ, Wallman JK, van Vollenhoven RF, Saevarsdottir S. Serum biomarkers for prediction of response to methotrexate monotherapy in early rheumatoid arthritis: results from the SWEFOT trial [published online February 1, 2019]. J Rheumatol. doi:10.3899/jrheum.180537