Methotrexate use lowers CVD risk in RA patients on biologics

Concomitant use of methotrexate (MTX) among patients with rheumatic arthritis (RA) initiating biologics results in a 24-percent reduced risk of cardiovascular disease (CVD) events, a study has shown.

“MTX has been associated with reduced risk for CVD events among patients with RA not exposed to biologic disease-modifying antirheumatic drugs (bDMARDs),” said the investigators, who conducted this retrospective study to examine the effect of MTX on CVD risk using 2006­–2015 Medicare claims data for RA patients receiving bDMARD.

Current MTX use, updated in a time-varying manner, was the main exposure. The primary endpoint was a composite of incident myocardial infarction (MI), stroke, and fatal CVD, while secondary ones were each event that comprised the primary outcome.

The investigators calculated incidence rates (IR) and 95 percent confidence intervals (CIs) using Poisson regression and examined the associations between MTX and CVD risk using Cox regression.

The study included a total of 88,255 bDMARD initiations and 1,861 CVD events. Patients had a mean age of 64.6 years, of whom 84.0 percent were female and 68.2 percent were non-Hispanic White.

The crude IRs for CVD events among patients unexposed and exposed to MTX were 17.9 (95 percent CI, 16.9–18.8) and 12.1 (95 percent CI, 11.1–13.2) per 1,000 patient-years, respectively.

The multivariable adjusted HR for CVD events associated with MTX was 0.76 (95 percent CI, 0.68–0.85). For MI, stroke, MI or stroke, and a composite of CVD outcomes, the multivariable adjusted HRs were 0.78 (95 percent CI, 0.66–0.91), 0.74 (95 percent CI, 0.62–0.88), 0.77 (95 percent CI, 0.68–0.86), and 0.82 (95 percent CI, 0.73–0.93), respectively.

Sensitivity and subgroup analyses showed robust results.