An evaluation of warfarin use at an urban district-level hospital in KwaZulu-Natal Province, South Africa

Abstract

Background. Warfarin is a commonly prescribed drug that needs to be monitored regularly.

Objectives. To evaluate the quality of care of patients on warfarin and to determine the cost-effectiveness of this drug in a South African district hospital setting.

Methods. Quality of care was assessed through a structured patient interview, and cost-effectiveness of warfarin was determined by retrospective review of all costs over a 6-month period.

Results. A total of 110 participants from the dedicated warfarin clinic at Wentworth Hospital, Durban, were enrolled over a 1-month period. The median cost of all warfarin-related expenditure was ZAR295.05 per patient per month (pppm) (interquartile range (IQR) 283.42 - 333.17), with a mean (standard error of the mean (SEM)) cost of ZAR394.90 (53.03). The median cost for patients with non-valvular atrial fibrillation was ZAR294.40 pppm (IQR 283.85 - 345.10) and the mean (SEM) cost was ZAR430.54 (116.14), compared with an estimated cost of ZAR545.96 and ZAR673.85 per month for rivaroxaban and dabigatran tablets, respectively. Of the participants interviewed (N=110), 69.1% agreed or strongly agreed that monthly international normalised ratio monitoring frustrated them, 74.5% agreed or strongly agreed that they sometimes wished that they did not have to take warfarin, and 84.5% would be willing to pay for a drug that required less frequent blood tests and clinic visits.

Conclusions. Warfarin still appears to be the most cost-effective drug in our setting, but it significantly affects patients’ quality of life. We suggest a prospective head-to-head trial to compare both cost-effectiveness and quality of life of patients on warfarin and the new oral anticoagulants at a district hospital facility.