Abstract 242: Comparison of Pharmacist-Managed Initial Dosing of Direct Oral Anticoagulants with Non-Pharmacist Practitioner Prescribing Patterns

Abstract

Background: There is currently a lack of data regarding pharmacist-managed DOAC (direct oral anticoagulant) therapy. The objective of this study was to assess the impact of pharmacist-managed initial dosing of apixaban and rivaroxaban utilizing a Pharmacy and Therapeutics Committee approved guideline when compared with general practitioner/cardiologist practitioner prescribing practices for patients with Non-Valvular Atrial Fibrillation (NVAF). Methods: A retrospective, chart review was performed during the period of January 2015 to January 2018 and included adults 18-95 years old, who were prescribed apixaban or rivaroxaban for documented NVAF. Patients eligible for this study were split up into two cohorts: a pharmacist-managed cohort and a non-pharmacist-managed cohort. The primary endpoint of the study was the percentage of patients who received appropriate initial apixaban or rivaroxaban dosing. Any incorrect initial doses of apixaban or rivaroxaban were then analyzed to determine the reason for error. The secondary endpoints included thromboembolic and hemorrhagic adverse events. Exploratory analyses included: provider follow up-time, inappropriate DOAC use in valvular atrial fibrillation (VAF), and correct transition from warfarin to DOAC. Results: For the primary endpoint, the pharmacist practitioner was significantly more accurate when initially dosing apixaban and rivaroxaban compared to non-pharmacist practitioners (97% [63 out of 65] vs. 74% [48 out of 65] correct prescriptions, p=0.001). When evaluating the reason for error in prescribing, non-pharmacist providers were significantly less likely to dose the patient appropriately based on renal function or drug interactions (p=0.003). For the secondary endpoint of hemorrhagic or thromboembolic events, there were no statistically significant differences among the two provider types. The exploratory analyses revealed that 3% (2 out of 65) of the patients in the non-pharmacist managed cohort had VAF and received a DOAC for antithrombotic therapy. The patients in the pharmacist managed cohort had zero patients receive a DOAC for VAF. The pharmacist was also significantly better at transitioning patients from warfarin to DOACs correctly compared to non-pharmacist practitioner (100% [12 out of 12] vs. 50% [3 out of 6], p=0.025) and following up with patients within a four-month time frame compared to non-pharmacist practitioners (100% [65 out of 65] vs. 82% [53 out of 65], p=0.001). Conclusion: Additional research is required to evaluate the benefits of pharmacist-managed anticoagulation; however, based on the results of this study, pharmacists are significantly better equipped to initiate DOAC therapy for patients with NVAF. Based on the findings of the study results, pharmacist-managed DOAC services may be transferrable to a variety of different disease states requiring anticoagulation therapy.