Abstract and Introduction
Aims: The objective of this study was to evaluate the cost–effectiveness of rivaroxaban versus the low-molecular-weight heparins (LMWH) enoxaparin and dalteparin for the prevention of venous thromboembolism (VTE) after total hip replacement and total knee replacement in Sweden.
Methods: The model included acute venous thromboembolic events and long-term complications over a 5-year time horizon represented by an acute and a chronic phase with 1-year cycles. Transition probabilities were derived from the Regulation of Coagulation in Orthopaedic Surgery to Prevent Deep Vein Thrombosis and Pulmonary Embolism (RECORD) clinical trials.
Results: In patients undergoing total hip replacement, the incremental cost per additional quality-adjusted life-year of extended prophylaxis for 35 days with rivaroxaban versus 14 days of prophylaxis with enoxaparin or dalteparin was SEK29,400 and SEK35,400, respectively. In total knee replacement patients, 14 days of rivaroxaban dominated 14 days of LMWH as prophylaxis for VTE.
Conclusion: The results of the economic model consistently showed that, over a 5-year period, rivaroxaban is a cost-effective alternative to 14 days of LMWH for VTE prophylaxis in Sweden.
Major orthopedic surgery, such as total hip replacement (THR) and total knee replacement (TKR), is associated with an increased risk of venous thromboembolism (VTE). Milbrink and Bergqvist estimated the incidence of VTE in Swedish patients to be approximately 0.6%.
The consequences of VTE and its long-term complications can significantly impair health-related quality of life (QoL) for patients, while treatment of the condition and its recurrent complications translate into substantial costs for the healthcare provider. Costs are incurred both in the period of hospitalization immediately following the THR and TKR, as well as in the months following discharge from hospital. These complications are often not associated with surgery, since the majority of cases observed in the Milbrink and Bergqvist study occurred after discharge from hospital.
Owing to the high cost of universal screening, the cost of VTE treatment and the recurrent nature of the condition, it is recommended that high-risk patients in Sweden are administered prophylactic treatment. Pharmaceutical thromboprophylaxis is administered in hospital and post-discharge. The most common approach to VTE prophylaxis in Sweden involves a minimum of 7–10 days of enoxaparin or dalteparin therapy (or until the patient is mobilized) and up to 30 days for high-risk patients (e.g., those who are undergoing THR or have experienced a deep vein thrombosis [DVT] or pulmonary embolism [PE] earlier). Although this substantially reduces the risk of VTE compared with no prophylaxis, recent clinical trials suggest that approximately 1.2–2.0% of patients still suffer a symptomatic VTE and approximately 9.3–18.9% of patients suffer any venous thromboembolic event after surgery.[3,4]
A number of studies evaluated the cost implications and cost–effectiveness of thromboprophylactic agents in Sweden.[5–7] The agents were the most recent developments in VTE prophylaxis, including unfractionated heparin (UFH) versus low-molecular-weight heparins (LMWHs) and fondaparinux versus enoxaparin.[6,7]
Rivaroxaban (Xarelto®, Bayer Schering Pharma AG) is a once-daily, orally administered VTE prophylaxis agent. It represents an alternative to current prophylaxis of subcutaneous LMWH injections in Sweden and has not been evaluated previously from a cost–effectiveness perspective. The objective of this study was to evaluate whether rivaroxaban is a cost-effective alternative to enoxaparin and dalteparin for patients after THR or TKR surgery in Sweden.
Expert Rev Pharmacoeconomics Outcomes Res. 2011;11(5):601-615. © 2011 Expert Reviews Ltd.
Cite this: Cost–Effectiveness of Rivaroxaban Versus Heparins for Prevention of Venous Thromboembolism After Total Hip or Knee Surgery in Sweden - Medscape - Oct 01, 2011.