Outcomes of venous thromboembolism in multiple myeloma: A nationwide analysis of anticoagulation strategies

Abstract Background Multiple Myeloma (MM) has an increased risk of venous thromboembolism (VTE) involving the disease-related and treatment-related mechanisms. The current guideline from ASH has a conditional recommendation regarding the use of anticoagulation for VTE prophylaxis in ambulatory patients with MM receiving lenalidomide-, thalidomide-, or pomalidomide-based regimens. The study aims to evaluate clinical outcomes and resource use among MM patients who develop VTE, comparing those not on anticoagulation, those receiving aspirin, and those receiving other anticoagulants. Methods We conducted a retrospective analysis of the 2022 National Inpatient Sample (NIS) database using STATA 19.5 to identify hospitalizations involving MM with VTE. We then categorized the patient population based on their anticoagulation status, identifying those on anticoagulation therapy and those who developed VTE without it. Analysis of variance (ANOVA) was used to compare mean age, length of stay, and total hospital charges among these groups. Statistical significance was assessed using appropriate tests, with a p-value <0.05 considered significant. Results In 2022, there were 23,248 hospitalizations with MM. Of these, 2,037 developed VTE. Patients were categorized into three groups: MM patients who developed VTE without anticoagulation (n=966), with aspirin (n=257), and with low-molecular-weight heparin (n=933). The mean age was slightly lower in the no-anticoagulation group (69 years) compared to the aspirin (71 years) and low-molecular-weight heparin (70 years) (p<0.03). The no-anticoagulation group had significantly longer LOS (10 days vs. 6.5 and 6.3 days; p<0.001), higher hospital charges ($164,987 vs. $80,833 and $103,564; p<0.001), and increased mortality (9.95% vs. 2.17% and 2.89%; p<0.001) compared to those on aspirin or low-molecular-weight heparin. The mortality was significantly higher in MM patients who were not on any anticoagulation (9.95%) when compared to the aspirin group (2.17%) and the low-molecular-weight heparin (2.89%), with a p-value <0.001. The Multivariate logistic regression performed after adjustment of confounders showed that the Odds ratio of mortality of MM with VTE was 3.3 with a p-value of <0.001 and a 95% confidence interval of 2.5 to 4.2. Conclusion MM patients who developed VTE without any prophylactic antithrombotic therapy experienced worse outcomes, including longer hospitalizations, higher healthcare costs, and increased mortality. Use of aspirin or anticoagulants was associated with improved clinical outcomes, underscoring the importance of reinforcing thromboprophylaxis in MM patients.