Assessment of a Pharmacist-Led Direct Oral Anticoagulant Monitoring Clinic

Abstract

Direct oral anticoagulants (DOACs) are recommended as first-line therapy for treatment and prevention of venous thromboembolism (VTE) and prevention of stroke related to nonvalvular atrial fibrillation. Recent publications have suggested incorporating DOAC monitoring into anticoagulant management clinics. The Eastern Health Adult Outpatient Thrombosis Service (Newfoundland and Labrador) includes a pharmacist-led DOAC monitoring clinic that uses standardized evidence-based care processes. To describe a new pharmacist-led DOAC monitoring clinic and to assess patients' adherence to medication therapy, adherence to guideline-recommended frequencies for blood work, and adverse and non-adverse events. This retrospective chart review involved patients who attended their first visit to the DOAC clinic between October 10, 2017, and May 31, 2018. Patients were followed until November 30, 2018. Data were abstracted from electronic hospital records and the provincial pharmacy network. Descriptive statistics were used to analyze the data: categorical variables were presented as frequencies and percentages; continuous variables were analyzed and presented as means with standard deviations and, where applicable, as medians with interquartile ranges. Forty-seven patients, who attended a total of 74 clinic visits, were included. Twenty-eight patients (60%) were adherent to their DOAC therapy. All patients had blood work completed before each clinic appointment. The mean time between the first and second sets of blood tests was 6.2 (standard deviation [SD] 1.4) months and between the second and third sets of blood tests was 5.1 (SD 1.0) months. There were no episodes of VTE or major bleeding. There was 1 cerebrovascular accident (3.2 events per 100 person-years, 95% confidence interval [CI] 0.2-15.7) and 5 episodes of clinically relevant non-major bleeding (12.8 events per 100 person-years, 95% CI 4.1-30.1). Pharmacists identified 51 issues at the clinic appointments, of which 48 were medication-related. Referral to the Thrombosis Service physician was required to resolve 8 (16%) of the issues identified. A brief discussion between the Thrombosis Service physician and pharmacist was required to resolve 30 (59%) of the issues, with 13 (25%) resolved by the pharmacist alone. This study described the implementation and outcomes of a novel pharmacist-led DOAC clinic. Clinic patients underwent blood work at recommended intervals and received guidance on adherence and adverse events; as such, patients had follow-up that aligned with guideline recommendations.