Cost-effectiveness of two models of management for patients on chronic warfarin therapy--a Markov model analysis.

Allocation of additional resources for establishing or expanding anticoagulation clinic (AC) services is a significant concern for healthcare decision-makers when the payer is also the provider of the healthcare system. The majority of anticoagulated patients in Hong Kong are managed by routine medical care (RMC) instead of ACs, possibly due to the lack of local cost-effectiveness analysis of the AC setting. The aim was to compare the clinical and economic outcomes of anticoagulated patients who were managed by AC or RMC from the perspective of a public health organization in Hong Kong. A Markov model was designed to simulate, over 10 years, the economic and clinical outcomes of patients receiving chronic warfarin therapy managed by AC or RMC. The transition probabilities were derived from literature. Resource utilization was retrieved from patients managed by AC and RMC in Hong Kong. Sensitivity analysis was conducted to examine the robustness of the model. The total number of events per 100 patient-years and the direct medical cost per patient-year in the AC and RMC groups were 9.5 and USD 840, and, 19.3 and USD 1,179, respectively. The results of the model were sensitive to the variation of the probability of major bleeding in the AC group. In conclusion, the coordinated care provided by an anticoagulation clinic appears to be more cost-effective than routine medical care in the management of warfarin therapy from the perspective of public health organization in Hong Kong.