Abstract
BACKGROUND: Guidelines suggest pharmacological thromboprophylaxis for patients with multiple myeloma (MM) treated with immunomodulatory drugs due to a high risk of venous thromboembolisms (VTE). OBJECTIVES: To analyze rates of VTE and bleeding, risk profiles, and patterns of thromboprophylaxis in MM patients. METHODS: For this cohort study, all consecutive patients with newly diagnosed MM between January 2012 and January 2022 who received induction treatment at our center were included. Characteristics at time of diagnosis, antimyeloma treatment, thromboprophylaxis, and thrombotic and bleeding events during 2-year follow-up were recorded. RESULTS: Of 293 patients screened, 208 were included. During follow-up, VTE occurred in 19 (9.1%) patients, any bleeding in 35 (16.8%), and major bleeding in 14 (6.7%). IMPEDE-VTE score predicted VTE, but SAVED score did not. Two-year cumulative incidences of VTE by type of thromboprophylaxis prescribed after diagnosis (1) and at landmark 3 months (2) for aspirin versus standard anticoagulation (low molecular weight heparin or vitamin K antagonist) versus direct oral anticoagulants versus no antithrombotic therapy were (1) 18.73% (95% CI: 7.43-33.97) versus 2.78% (95% CI: 0.21-12.6) versus 4.00% (95% CI: 0.27-17.36) versus 9.88% (95% CI: 5.03-16.67) and (2) 12.46% (95% CI: 4.48-24.74) versus 5.56% (95% CI: 0.34-23.06) versus 0.00% versus 10.51% (95% CI: 4.88-18.64), respectively. Major bleeding rates did not significantly differ between antithrombotic strategies. CONCLUSION: We observed a high rate of VTE and bleeding in patients with newly diagnosed MM. Use of anticoagulant therapy including direct oral anticoagulants was associated with a trend toward reduced risk of VTE compared with aspirin or no antithrombotic therapy. Bleeding risk was high irrespective of antithrombotic strategy.