The role of clinical pharmacy anticoagulation services in direct oral anticoagulant monitoring

Abstract

The role of dedicated anticoagulation management services (AMS) for patients receiving direct oral anticoagulant (DOAC) therapy is unclear. The objective of our study was to describe DOAC management in patients who were and were not managed by an AMS. We conducted a retrospective cohort study among patients with atrial fibrillation at the University of Utah Health (UUH) who received DOAC therapy between January 2013 and June 2016. Patients in the AMS group were managed by a pharmacist-led AMS whereas those in the non-AMS group were managed by other providers. The number and type of provider encounters and interventions related to DOAC therapy and a composite endpoint of thromboembolism, bleeding, and all-cause mortality were recorded. Overall, 90 and 370 patients were managed in the AMS and non-AMS groups, respectively. AMS group patients had greater chronic disease burden as measured by the Charlson comorbidity index. AMS group patients had more frequent DOAC-related encounters than non-AMS group patients but both groups had similar DOAC therapy intervention rates. Over half of patients in the AMS group received potentially duplicative interventions from their regular clinicians. The composite endpoint occurred in 18.9% and 13.5% of AMS and non-AMS group patients, respectively (p = 0.29). Patients managed by AMS providers were more complex and had more frequent encounters regarding their DOAC therapy than those managed by non-AMS providers. However, there was evidence of duplicative DOAC therapy management efforts. No difference between AMS and non-AMS groups in the composite clinical endpoint was detected.

Keywords: Anticoagulation; Bleeding; DOAC; NOAC; Pharmacist management.

Figure 1:

Flowchart of Group Allocation of Atrial Fibrillation Patients Prescribed DOAC Therapy in the University of Utah Health System AMS-Anticoagulation Management Service; DOAC-direct oral anticoagulant; UUH-University of Utah Health

Figure 2.

Direct Oral Anticoagulant Therapy Interventions Categorized by Provider Type

Figure 3.

Kaplan-Meier Estimates of Event-free Survival and Hazard Ratio [95% confidence interval] from Cox-proportional Hazard Regression Models. Legend: Orange lines: Estimates for anticoagulation management service group; Blue lines: Estimates for non-anticoagulation management service group; Solid lines Primary composite endpoint including ischemic stroke, transient ischemic attack, peripheral arterial embolism, major bleeding: Clinically relevant non-major bleeding, minor bleeding and death; Dotted lines: Composite of major endpoints including ischemic stroke, peripheral arterial embolism, major bleeding and death HR-hazard ratio