OBJECTIVES: Patient-relevant bleeding events are types of bleeding or bruising that do not require medical intervention but are bothersome to patients. These events often occur as a side effect of oral anticoagulant (OAC) use in patients with atrial fibrillation (AF); however, there is currently no patient-reported outcome (PRO) measure to assess their burden on patient health-related quality of life (HRQoL) and effect on OAC adherence. This research sought to develop the Anticoagulant Bleeding Burden Adherence Confidence Assessment Scale (ABBA-CAS), a de novo PRO measure, to fill this gap in measurement tools.

METHODS: A targeted literature review was conducted to identify the impacts of patient-relevant bleeding events on patient HRQoL. These impacts formed the basis of a draft conceptual model. Key opinion leaders (KOL), including clinician and patient stakeholders, provided feedback on the model, which was then revised. The finalized conceptual model, along with the results of a review of 10 PROs in similar conceptual spaces, served as the foundation for the draft ABBA-CAS. Written KOL feedback of the ABBA-CAS was obtained and used to revise the measure. The ABBA-CAS was then evaluated for readability.

RESULTS: Ten articles served as the foundation for the conceptual model, which consisted of nine impact areas organized within three domains (emotional/psychological, physical, and lifestyle/activities of daily living). The ABBA-CAS is an 18-item PRO measure, with a 14-day recall period, measuring the frequency of OAC-related bleeding and bruising, and the severity and frequency of their associated impacts on HRQoL and OAC adherence.

CONCLUSIONS: The ABBA-CAS was drafted with reference to Food and Drug Administration (FDA) guidance to measure the impact of OAC-related patient-relevant bleeding events on HRQoL and OAC adherence in AF patients. Planned future work includes cognitive debriefing and psychometric evaluation of the ABBA-CAS among AF patients taking OAC medications who experience patient-relevant bleeding events.