Cost-effectiveness of the pharmacist-assisted warfarin monitoring program at a Medical Center in Taiwan

Abstract

Objective: To investigate the cost-effectiveness of the first patient self-paying pharmacist-assisted warfarin monitoring (PAWM) program in Taiwan.

Design: A Markov model with a 1-month cycle length and a 20-year time horizon was employed in this study. The model is composed of the following eight states: three no-event states (i.e. 'subtherapeutic,' 'within therapeutic' and 'supratherapeutic' states), two serious adverse events (AEs) (i.e. bleeding and thromboembolism), two sequelae states and death. The likelihood of events, costs and utilities were derived from local databases and literature, if applicable. This study was conducted with a payer's perspective and all costs were discounted with a rate of 3%.

Setting: A pharmacist-led clinic.

Participants: A hypothetical cohort of 10 000 participants.

Intervention(s): PAWM versus usual care.

Main outcome measure(s): Average quality-adjusted life-years (QALYs) gained and cost increments per patient, and incremental cost-effectiveness ratios (ICERs).

Results: The PAWM program resulted in an average of 0.13 QALYs gained and a cost increment of NT$53 850 (US$1683) per patient. As the ICER (NT$410 749 [US$12 836]) was less than the gross domestic product per capita (NT$631 142 [US$19 723]), the PAWM was considered to be very cost-effective. The sensitivity analyses suggested that our result was robust and that the PAWM program had an 86% probability of being very cost-effective.

Conclusions: Even if the costs saved from avoiding AEs were thought to be minimal due to the low-medical expenditures in Taiwan, the PAWM program was demonstrated to be economical. According to our findings, the policymakers should consider reimbursing such a service.

Keywords: Markov model; cost-effectiveness; incremental cost-effectiveness ratio (ICER); pharmacist-assisted warfarin monitoring (PAWM); warfarin.