Category: Professional Posters
Purpose: The advantage of direct acting oral anticoagulants (DOACs) over vitamin K antagonists include reduced number of drug interactions, no routine blood testing of the INR required and no dietary restrictions. A county health system added rivaroxaban and apixaban to their formulary in 2012 and 2017 respectively. Rivaroxaban and Apixaban are FDA approved for nonvalvular atrial fibrillation and venous thromboembolism. The ambulatory clinical pharmacists in the anticoagulation clinic assess all new warfarin patients for DOAC eligibility. This review will reveal all remaining patients on warfarin and those that are potentially eligible to be switched to a DOAC.
Methods: A retrospective electronic chart review was conducted on two hundred and eighty-five patients receiving warfarin from January 2018 through October 2018. An outpatient utilization report for warfarin for this time frame was obtained from Epic Business Intelligence. The report characteristics included patient demographics, dispensing location, documented indications, warfarin status, DOAC eligibility and reason not on a DOAC.
Results: There were two hundred and eighty-five outpatients on warfarin from January 2018 through October 2018. Fifty-nine percent (168/285) of patients were male and forty-one percent (117/285) were female. The average age was 60 years of age. Twenty-four percent (68/285) of the patients had a documented indication of atrial fibrillation with a mitral or aortic valve replacement. Thirty-eight percent (108/285) had a pulmonary embolism or a deep vein thrombosis as well as thirty-eight percent (109/285) also had non-valvar atrial fibrillation or flutter. Eighty-six percent (246/285) are currently on warfarin while fourteen percent (39/285) were discontinued due to either presently being on a DOAC, lost to follow-up, pregnancy, no longer requiring anticoagulant therapy or an adverse drug event. The reasons the two hundred and forty-six patients remain on warfarin include the following. Twenty-seven percent (67/246) of the patients had valve replacement, twelve percent (30/246) was due to patient preference, one percent was because of advanced age, less than one percent had a high BMI, twenty-one percent was due to renal impairment or dialysis, two percent had a drug interaction or contraindication and four percent was due to cost. The remaining nine percent (23/246) were formerly on a DOAC but discontinued.
Conclusion: There were only twenty-two percent (54/246) of warfarin patients who were potentially eligible to be switched to a DOAC. The names of these patients were forwarded to the ambulatory clinical manager for further review. Although DOACs are typically more expensive, warfarin and rivaroxaban have comparable pricing in this 340 B institution. This county health system has successfully and appropriately switched the majority of their patients on warfarin to one of the DOACs currently on the formulary.