Kenneth C Wiley, Mary K Maneno, Yolanda McKoy-Beach and Monika Daftary
Background: There are limited studies addressing patient's willingness to switch to a new anticoagulant from warfarin. The goal of this study was to determine the effect of patient knowledge and satisfaction with warfarin therapy on willingness to switch to a new oral anticoagulation therapy in an urban clinic. Methods: A cross-sectional study was conducted among warfarin-treated patients attending a pharmacist-run urban anticoagulation clinic at Howard University Hospital from August 2014-February 2015. The primary outcome evaluated was willingness to switch to a new oral anticoagulant. Other variables assessed include social demographics, clinic factors, patient knowledge and satisfaction. The modified anti-clot treatment survey (ACTS), the oral anticoagulant knowledge survey (OAKS), and a validated willingness to switch survey were used to measure patient knowledge (high ≥ 75%), satisfaction (Likert scale ≥ 4) and willingness to switch (Likert scale ≥ 4), respectively. Statistical analysis was conducted using (Statistical Package for the Social Sciences (SPSS) version 22.0. Results: A total of 100 patients on warfarin treatment were included. The majority of participants were retired/disabled (59%), mostly African American (86%), and male (55%). The mean willingness to switch score was 21.59 (out of 35). Patients were most willing to switch to an alternative agent which required less follow up (3.55 ± 1.77) and had fewer drug interactions (3.75 ± 1.67). Factors associated with willingness to switch varied based on patient preferences. The only predictor of willingness to switch was low satisfaction (p=0.002). Knowledge was not associated with willingness to switch (p=0.249). Conclusion: Patients in an anticoagulation clinic had low knowledge of their warfarin therapy, were overall satisfied with warfarin treatment, but were willing to consider using a new oral anticoagulant that was more convenient especially if low satisfaction with warfarin. Further studies should be directed toward patient preferences in determining optimal regimen.