PCV108 - PRESCRIBING CHOICE AND THE COST OF ANTICOAGULATION IN ATRIAL FIBRILLATION: A REAL WORLD STUDY COMPARING HEALTHCARE EXPENDITURE WITH WARFARIN AND APIXABAN

Abstract

The availability of direct oral anti-coagulants (DOACs) has enabled additional prescriber choice for managing stroke risk in patients with non-valvular atrial fibrillation (NVAF). However, there is limited data comparing total resource utilisation associated with warfarin and apixaban use in hospitalised patients with newly-diagnosed NVAF. This study aimed to evaluate hospital length of stay (LOS), drug acquisition and administration costs, international normalized ratio (INR) monitoring and related staff contacts, in these patients. This was a retrospective, dual time point, cross-sectional study of medical records of hospitalised patients, newly-diagnosed with NVAF as their primary cause of admission, initiated on anticoagulation in Jersey. Data were collected around the availability of warfarin (July 2011-June 2012) and apixaban (July 2016-June 2017). Costs were expressed as 2018 GBP. Statistical analysis included descriptive statistics (t-tests, chi-squared tests) assessing differences in baseline characteristics, and Wilcoxon rank sum to test for differences between mean LOS. 46 patients (>18 years) across both audit periods were eligible for analysis, with no statistically significant differences in baseline characteristics observed between the two cohorts. Mean LOS was 8.19 days (SD: 6.59) in the warfarin cohort (n= 15) and 2.23 days (SD: 2.64) in the apixaban cohort (n=31), a difference of -5.96 days (p≤0.001). Mean per-patient cost for overall healthcare resource utilisation was £3,506.99 (LOS = £2,783.50 [79.4%], anticoagulation= £1.22 [0.03%], INR= £93.33 [2.7%], INR-related staff contacts= £611.07[17.4%], enoxaparin administrations=£17.87 [0.5%]) in the warfarin cohort, and £840.13 (LOS = £757.50 [90.2%], anticoagulation= £82.63 [9.8%]) in the apixaban cohort, resulting in a 76% reduction in medical expenditure compared to warfarin. This study suggests that prescribing choice should not be determined by drug acquisition cost alone. The utilisation of apixaban in hospitalised, newly-diagnosed NVAF patients led to a shorter LOS, the avoidance of INR testing and administration of enoxaparin.