Comparative cost-effectiveness of anticoagulation with bivalirudin or heparin with and without a glycoprotein IIb/IIIa-receptor inhibitor in patients undergoing percutaneous coronary intervention in Sweden: a decision-analytic model.

OBJECTIVE: This study modeled the comparative costs and effectiveness of anticoagulation with bivalirudin alone, heparin alone, and heparin combined with a glycoprotein IIb/IIIa-receptor inhibitor (GPI) in patients undergoing percutaneous coronary intervention (PCI) in Sweden.

METHODS: GPIs are prescribed for -40% to 50% of patients undergoing PCI in Sweden. However, because treatment practices vary between hospitals, the model analyzed a cohort in which different proportions of patients (0%-100%) would receive a GPI in addition to heparin and the remaining patients would receive heparin monotherapy. This mixed cohort was compared with a cohort treated with bivalirudin. Abciximab was used as the GPI comparator, as this is the only GPI currently approved in Sweden for patients undergoing PCI. Pooled data from 3 studies (REPLACE-2 [second Randomized Evaluation of PCI Linking Angiomax to Reduced Clinical Events], ESPRIT [European/Australasian Stroke Prevention in Reversible Ischaemia Trial], and EPISTENT [Evaluation of Platelet IIb/IIIa Inhibitor for Stenting]) were used as the source for the probabilities of myocardial infarction (MI), urgent revascularization (UR), major and minor bleeding (Thrombolysis in Myocardial Infarction study definitions), and death. Treatment costs associated with these complications were obtained from 4 Swedish hospitals, and official drug prices were obtained from the Swedish Pharmacopoeia. All costs were presented in 2006 Swedish kronor (SEK). The model was evaluated over a 30-day time frame from the perspective of a Swedish hospital. The modeled patient population was 63 years old, weighed 78 kg, and was 75% male.

RESULTS: Compared with a pattern in which heparin plus a GPI was used in 50% of all PCIs and heparin alone was used in the remaining 50%, bivalirudin treatment was associated with a significant reduction in all complications in the model (P < 0.05), including a mean of 18.2 fewer MIs, 1.6 fewer URs, 15.3 fewer bleeding events, and 1.3 fewer deaths per 1000 treated patients. Bivalirudin therapy also was associated with a significant reduction in total drug and health care costs per patient (SEK -1301; 95% Cl, -1367 to -1229). The benefit of bivalirudin was sensitive to the rate of GPI use: additional reductions in rates of MI, UR, and death were seen at lower rates of GPI use, and additional reductions in rates of bleeding and costs of drugs and health care utilization were seen at higher rates of GPI use.

CONCLUSIONS: In this model, anticoagulation with bivalirudin in patients undergoing PCI was cost-effective compared with heparin alone and heparin plus a GPI. In a hypothetical Swedish hospital unit using equal proportions of heparin alone and heparin plus a GPI, a switch to bivalirudin would reduce the risk of both ischemic events and bleeding events, resulting in savings in total drug and health care costs.