For patients with rheumatoid arthritis (RA) who failed to respond to methotrexate, switching to a biologic disease-modifying antirheumatic drug (bDMARD) was more effective compared with a regimen with conventional synthetic DMARDs (csDMARDs) with or without glucocorticoids, according to results published in the Annals of the Rheumatic Diseases.
The study included participants with newly-diagnosed RA whose disease had failed to respond to initial treatment with methotrexate. The researchers categorized subsequent DMARD treatment regimens into the following groups: 1 or more csDMARDs (n=143), combination treatment with csDMARDs plus glucocorticoids (n=278), and treatment with a bDMARD with or without csDMARDs (n=89).
The researchers used multinomial regression to estimate multiple propensity scores that reflected the likelihood of treatment for each treatment regimen. They used linear mixed model analyses to analyze treatment responses per category at 6 and 12 months.
After 6 months, the researchers found that propensity score-adjusted treatment responses yielded a change in Disease Activity Score (DAS) per year of −2.00 (95% CI, −2.65 to −1.36) if participants received a bDMARD, −0.96 (95% CI, −1.33 to −0.59) if participants received csDMARDs with glucocorticoids, and −0.73 (95% CI, −1.21 to −0.25) if participants received csDMARDs only.
After 1 year of follow-up, the changes in DAS were −0.91 (95% CI, −1.23 to −0.60), −0.43 (95% CI, −0.62 to −0.23), and −0.39 (95% CI, −0.66 to −0.13), respectively, for bDMARDs, csDMARDs with glucocorticoids, and csDMARDs only.
“In conclusion, in this analysis with real life clinical data, we have shown that after multiple [propensity score] adjustment patients with RA who had failed initial treatment with methotrexate monotherapy experienced more decrease in disease activity after switching to treatment with a bDMARD than to treatment with csDMARD(s) [with] glucocorticoid or to csDMARD(s) alone,” the researchers wrote. “Furthermore, treatment-survival was better in patients receiving treatment with a bDMARD.”
Bergstra SA, Winchow LL, Murphy E, et al. How to treat patients with rheumatoid arthritis when methotrexate has failed? The use of a multiple propensity score to adjust for confounding by indication in observational studies [published online October 16, 2018]. Ann Rheum Dis. doi:10.1136/annrheumdis-2018-213731