Category: Federal Forum Posters
Purpose: International normalized ratio (INR) time in therapeutic range (TTR) is important for both safety and efficacy of warfarin therapy. The TTR at this facility is approximately 70 percent, but there remain patients with poor TTR. This places them at increased risk for complications including stroke, thromboembolism, and major bleeding. Practice guidelines and literature support switching patients to direct oral anticoagulants (DOACs) in the presence of low TTR. The purpose of this project was to optimize the rate of switches, evaluate acceptance rate for switching, identify reasons patients decline switching, assess adverse events, and evaluate cost-savings.
Methods: Phase 1: Fifty patients with TTR less than 60 percent were systematically identified from dashboard data and screened for DOAC eligibility by a pharmacy resident. Alerts were placed in the Anticoagulation Management Tool (AMT) for patients eligible for a DOAC switch. Upon seeing the alert, the anticoagulation pharmacist completing follow-up would confirm eligibility, discuss with the patient, and implement the DOAC switch if the patient was agreeable.
Phase 2: Chart reviews were conducted on all patients who were switched to a DOAC because of low TTR between February 2017 and January 2018. Data gathered for the safety and cost analyses included adverse events, sustained DOAC use 90 days after switching, and number of encounters per year before and after switching to a DOAC.
Results: Of the patients offered a switch to a DOAC, 71 percent accepted a switch to a DOAC. Of those that declined, the most common reason was safety concerns. Forty-eight patients were included in the safety analysis. At ninety days after switching to a DOAC, four patients had a bleeding event, zero had a thromboembolic event, and one patient had dyspepsia. Approximately 94 percent of patients continued on their initial DOAC. There was a 30 dollar cost-savings per patient per month associated with a reduction in pharmacist time completing follow-up in the first year after switching a patient on warfarin with poor TTR to a DOAC.
Conclusion: A majority of patients with low TTR on warfarin were accepting of a switch to a DOAC. Patients who switched to DOACs had low rates of adverse events. This pilot project suggests potential for practice transformation for poorly controlled warfarin patients.
Irene Chung– Student, University of Wisconsin-Madison School of Pharmacy, Janesville