Patient-level adherence and interventions in an interdisciplinary DOAC clinic.

BACKGROUND

Direct oral anticoagulants (DOACs) are high risk medications with short half-lives making adherence vitally important. Global measures for adherence have been described; however, there is a lack of patient-level data on adherence.

METHODS

This prospective, single-center study in an interdisciplinary internal medicine clinic included patients referred by their primary care physician for DOAC therapy evaluation. Patients were interviewed by a clinical pharmacist who confirmed dose and indication. Adherence was evaluated by asking how it was taken, at what time(s) of the day, and how many doses of their DOAC were missed. Labs and concomitant drugs were evaluated and patients received medication counseling. If any issues arose, the pharmacist would work together with the physician to resolve them.

FINDINGS

Of 116 visits from 72 patients, an intervention was needed in 79 visits (68·1%). The most common problem identified was related to adherence: non-adherence to timing of dosing (n = 30), non-adherence to frequency of dosing (n = 5), and non-adherence to administration with food when indicated (n = 11). Adherence issues were present in 11 (61·1%) visits in patients taking rivaroxaban and 31 (33·0%) visits in patients taking apixaban.

INTERPRETATION

An interdisciplinary DOAC service provided interventions for the majority of patients referred for DOAC therapy evaluation. The most frequent problem was non-adherence, with more than a third of patients found to be non-adherent to the timing of their medication administration.