Multiple myeloma: retrospective assessment of routine thromboprophylaxis and utility of thrombotic risk scores

Background

The high risk of venous thromboembolism (VTE) in multiple myeloma (MM) warrants primary thromboprophylaxis for most patients. Myeloma-specific thrombotic risk scores (TRSs), such as IMPEDE-VTE, SAVED, and PRISM, were developed to improve risk assessment and guide antithrombotic strategies. Their performance is variable and has not yet been tested in Latin America.

Objectives

We aimed to assess the use of primary thromboprophylaxis, the incidence of VTE and bleeding events, and the effectiveness of TRSs in patients with newly diagnosed MM.

Methods

This was a retrospective, single-center study. Cumulative VTE rates and TRS performance were analyzed using survival and receiver operating characteristic curves.

Results

The study included 250 newly diagnosed MM patients; the vast majority (98.6%) received aspirin as thromboprophylaxis. VTE occurred in 8% within the initial 6 months, increasing to 14.8% over a median follow-up of 19 months. High rates of major bleeding (4.8%) and clinically relevant nonmajor bleeding (4.4%) events were documented. A minimal proportion (0.8%, 0.5%, and 1.2%) of patients were classified as low risk by IMPEDE-VTE, PRISM, and SAVED scores, respectively. Only IMPEDE-VTE exhibited a trend for distinguishing between intermediate-risk (7.14%) and high-risk (13.2%) groups (P = .09). PRISM and SAVED scores showed limited utility. VTE did not impact survival.

Conclusion

Aspirin as primary thromboprophylaxis carries an unacceptable risk of VTE and bleeding in patients at intermediate or high thrombotic risk. The IMPEDE-VTE score performed best, although without reaching statistical significance. We confirm that VTE does not portend poor overall survival in MM.