Outpatient management of chronic warfarin therapy at a pharmacist-run anticoagulation clinic during the COVID-19 pandemic

As a result of infection control regulations during the coronavirus disease 2019 (COVID-19) pandemic, anticoagulation clinics have been required to adjust their practices in order to continue providing safe and effective services for their patients. In accordance with a guidance document issued by the Anticoagulation Forum, The Brooklyn Hospital Center (TBHC) anticoagulation clinic in Brooklyn, New York implemented measures including telemedicine follow-ups instead of in-person clinic visits, extending the interval of INR testing, and reviewing eligible candidates for transition from warfarin to direct oral anticoagulants. This study describes the outcomes of one hospital-based clinic location in the 3 months before and after COVID-19 became a significant concern in the New York City area. The primary outcome of time-in-therapeutic range (TTR) for patients receiving warfarin was 60.6 % and 65.8 % in the pre-COVID and post-COVID groups, respectively (p = 0.21). For secondary outcomes, there was no difference in percent of therapeutic INRs (51.5 % pre-COVID v. 44.8 % post-COVID, p = 0.75) or percent of INRs ≥ 4.5 (2.3 % pre-COVID v. 4 % post-COVID, p = 0.27). Based on the data reported in this study, the short-term changes implemented at TBHC’s anticoagulation clinic did not appear to cause reductions in safety and efficacy of chronic warfarin therapy management.