Patient-Reported Barriers to Adherence Among ACEI/ARB Users from a Motivational Interviewing Telephonic Intervention

Hypertension is a common comorbidity among type 2 diabetes mellitus (T2DM) patients, which increases the risk of cardiovascular diseases. Despite the proven benefit of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) in this population, poor medication adherence is prevalent, resulting in higher complications and mortality rate. Motivational interviewing (MoI) has demonstrated effectiveness in improving medication adherence and identifying barriers. This study aimed to assess and identify patient-reported barriers to adherence to ACEI/ARB from an MoI telephonic intervention conducted by student pharmacist interns.

This retrospective study was conducted within an MoI intervention customized by past ACEI/ARB adherence trajectories for nonadherent patients with T2DM and hypertension enrolled in a Medicare Advantage Plan. Adherence barriers were extracted from the interviewers' notes by two independent researchers. Descriptive analysis was performed to summarize the overall frequency of barriers as well as across trajectory groups, identified from the initial and follow-up calls.

In total, 247 patients received the initial MoI call from which 41% did not communicate any barrier for ACEI/ARB use despite having low adherence. About 59% of the patients reported at least one barrier during the initial call. The most common barriers included forgetfulness, discontinuation by physicians, side effects, multiple comorbidities, polypharmacy, lack of knowledge about disease/medication, and cost issues. The follow-up calls helped with uncovering at least one new barrier for 28 patients who previously communicated a different issue with their medication during the first call. Additionally, 18 patients with initial denial for having any barrier to adherence reported at least one barrier throughout the follow-up calls.

This study summarized patient-reported barriers to ACEI/ARB adherence from an MoI telephonic intervention performed among nonadherent patients. Identifying specific barriers for patients may help to further design tailored interventions that address the barriers and improve adherence.