Abstract
BACKGROUND: Heart failure (HF) remains a major global health challenge. Guideline-directed medical therapy can effectively reduce mortality and hospitalizations; however, persistent medication nonadherence hinders its real-world impact. Although recent guidelines emphasize the pivotal role of pharmacists in supporting medication adherence, the mechanisms through which pharmacist-led patient education influences medication adherence remain underexplored. Identifying these mechanisms could inform the development of evidence-based strategies to optimize medication adherence and ultimately improve long-term outcomes in HF management. OBJECTIVE: This study aims to establish an Information-Motivation-Behavioral Skills (IMB) model to elucidate the mechanisms influencing medication adherence among patients with HF and to compare pre- and postintervention models for identifying significant pathways affected by pharmacist-led patient education. METHODS: In this longitudinal pretest-posttest study, all IMB constructs-information, personal motivation, social motivation, behavioral skills, and behavior-will be assessed using validated patient-reported outcome measures (PROMs) at baseline and three and six months postintervention; additionally, verbal inquiries will be conducted to evaluate the information construct and prescription refill data will be incorporated to supplement the behavior construct. Multigroup structural equation modeling will examine relationships among these constructs and their impact on medication adherence. Latent class growth modeling will also be employed to identify distinct adherence trajectory subgroups after six-month follow-up. EXPECTED OUTCOMES: The recruitment phase commenced in early May 2025. By evaluating structural changes in IMB pathways pre- and postintervention using PROMs, followed by identifying short-term and sustained responders, the study is expected to facilitate the precise targeting of pharmacist-led interventions to maximize clinical impact. This approach emphasizes the importance of tailoring healthcare delivery to individual medication adherence profiles. It aims to ensure that pharmacist-led patient education achieves its fullest potential in populations expected to benefit the most, particularly patients with HF-a perspective that, to our knowledge, has not been previously explored.