From the 2021 HVPAA National Conference
George Kontogiannis (Walter Reed), Thomas Brooke, Nana Safo, Andrew Nguyen, Tammera Nelson, Abhimanyu Chandel
Background
Warfarin is an anticoagulant utilized for the management of conditions including venous thromboembolism and atrial fibrillation. Warfarin administration requires regular laboratory monitoring and the medication is known to interact with a variety of foods and medications. Further, many patients prescribed warfarin are unable to maintain consistent time within the therapeutic range which has been associated with increased risk of systemic embolization, major bleeding, and mortality. Direct oral anticoagulants (DOACs) are an alternative to warfarin and do not require frequent laboratory monitoring, have fewer interactions with diet and medications, improve patient satisfaction, and are associated with improved clinical outcomes compared to warfarin. Additionally, prior analysis estimated a switch from warfarin to apixaban may produce a medical cost avoidance of $4440 per patient per year.
Objectives
We recently reported the results of the initial iteration of this house staff led quality improvement project where 31 high-risk patients receiving warfarin were transitioned to a DOAC. In this second iteration, the project was extended to target all eligible patients receiving warfarin within our anticoagulation clinic for consideration of transition to a DOAC.
Methods
Patients actively receiving warfarin for the management of non-valvular atrial fibrillation or venous thromboembolism within our anticoagulation clinic were identified. Records were reviewed for contraindications to DOAC administration. If no contraindications existed, the patient’s primary care physician or primary sub-subspecialist was alerted to the study team’s recommendation that warfarin could be discontinued and replaced with a suitable DOAC. Likewise, if there were no objections, the patient was then contacted by the study team to engage in shared decision making specifically reviewing the risks, benefits, and clinical factors prior to obtaining consent for transition to a DOAC. A clinical pharmacist in the anticoagulation clinic then coordinated the transition. The primary outcome evaluated was the number of eligible patients in the anticoagulation clinic changed to a DOAC. We also examined bleeding and clotting events in the cohort 1 year after transition.
Results
Ninety patients receiving warfarin were identified, with 67 of these patients noted to have a suitable indication and no contraindications to transition to a DOAC. 26 (39%) of these patients were switched to a DOAC therapy as a result of our intervention. After 12 months of follow up from the time of transition, one patient experienced an asymptomatic clotting event requiring reversion to warfarin therapy. Two episodes of bleeding were noted in the cohort that did not require alteration in anticoagulation therapy. No patients reverted to warfarin based on satisfaction with therapy or other considerations. Based on prior cost analysis, this quality improvement project resulted in an estimated total annual medical cost avoidance to this treatment facility of approximately $115,000.
Conclusions
This project documents the safety, efficacy, and feasibility of a house staff led quality improvement project transitioning patients from warfarin to a suitable DOAC.
Clinical Implications
Transitioning eligible patients from warfarin to a DOAC can be accomplished through a standardized house staff led protocol. Projects such as ours have the anticipated effect of avoiding medical costs while improving clinical outcomes and patient satisfaction.
