Watch for VTEs Early in TNF Inhibitor Course

January 5, 2015

A large study of insurance claims adds to the evidence linking rheumatoid arthritis treatment to the risk of venous thrombosis.

Kim SC, Solomon DH, Liu J, et al. Risk of Venous Thromboembolism in Patients with Rheumatoid Arthritis Initiating Disease-Modifying Antirheumatic Drugs. American Journal of Medicine. December 19, 2014. doi: http://dx.doi.org/10.1016/j.amjmed.2014.11.025

More data to ponder about the relation between rheumatoid arthritis (RA) treatment and the risk for venous thromboembolism (VTE). This cohort study, based on a review of insurance claims, reports a modest link between biological disease-modifying anti-rheumatic drugs (bDMARDs) and VTE.

It also finds an increased relative incidence in hospitalization for VTE. The risk is greatest in the first 180 days of treatment.

However, the absolute increase in risk is low, at under 1%.

The investigators identified 29,481 RA patients who were treated with conventional DMARDs, methotrexate, or bDMARDs for up to a year.

During followup, there were 191 VTE events,  31 of them tied to bDMARD use and 29 of those to tumor necrosis factor-α inhibitors.

While few of the comparisons were statistically significant, the hazard ratio of VTE for bDMARDs vs conventional DMARDs in the first 180 days was 2.48 (95% confidence interval: 1.14-5.39).