Economic Evaluations of New Oral Anticoagulants for the Prevention of Venous Thromboembolism After Total Hip or Knee Replacement: A Systematic Review

Background Total hip replacement (THR) and total knee replacement (TKR) surgeries are being performed with increasing regularity and are associated with a high risk of developing a venous thromboembolism (VTE). New oral anticoagulants (NOACs) may be more effective at preventing VTEs but are associated with more bleeding events versus traditional anticoagulants. Objective The objective of this systematic review was to identify published economic analyses of NOACs for primary VTE prophylaxis following THR and TKR surgeries, and to summarise the modelling techniques used and the cost-effectiveness results. Methods Electronic searches of MEDLINE, EconLit and The Cochrane Library were performed from January 2008 to February 2015. Reference lists of included articles and reviews were examined for relevant studies. Results Sixteen relevant economic analyses were identified, all of which used decision-tree structures to model acute events after surgery; 13 included a chronic-phase Markov module to capture long-term complications of VTE and recurrent VTE events. All studies included prophylaxis-related major bleeding events and captured both symptomatic and asymptomatic VTE-related events; nine studies distinguished between distal and proximal deep vein thrombosis events. Overall, rivaroxaban dominated enoxaparin in eight of 11 studies and dalteparin in one study, dabigatran dominated enoxaparin in five of seven studies and apixaban dominated enoxaparin in two of two studies. Rivaroxaban dominated dabigatran in four of four studies, apixaban dominated dabigatran in two of two studies and rivaroxaban dominated apixaban in one study. Conclusions The economic analyses showed reasonable consistency in the model structures used and the events captured. The results strongly suggested that NOACs are cost effective alternatives to low molecular-weight heparin. Dabigatran appeared to be the least cost effective NOAC. More research is needed to assess the cost effectiveness of apixaban and edoxaban.