OBJECTIVES: Angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin II receptor blockers (ARBs) are recommended for patients with comorbid diabetes mellitus and hypertension due to their favorable impact on microvascular and macrovascular events, cardiovascular outcomes, and mortality. Poor adherence to ACEI/ARB is a major public health concern. Motivational interviewing (MI) intervention is an effective patient-centered approach to improve adherence. The objective of this study was to evaluate the effectiveness of a telephonic MI intervention conducted by pharmacy students, tailored by the past ACEI/ARB adherence trajectories among nonadherent patients with comorbid diabetes mellitus and hypertension.

METHODS: Patients continuously enrolled in a Medicare Advantage Plan from July 2017-July 2021 with an ACEI/ARB prescription between July 2017-December 2017 were identified. Group-based trajectory modeling (GBTM) was used to identify 4 distinct patterns of ACEI/ARB adherence: adherent, gaps in adherence, gradual decline, and rapid decline in adherence. Patients from the 3 nonadherent trajectories were randomized either into MI intervention or control group. The intervention group received an initial call followed by 5 follow-up calls. The primary outcome was adherence measured as proportion of days covered (PDC) ≥ 0.80 for 1-year post-MI implementation. Multivariable logistic regression model evaluated the effect of the intervention on ACEI/ARB adherence.

RESULTS: This study included 240 patients who received intervention and 480 randomly selected controls. Patients who had received ≥ 4 calls were more likely to be adherent than those who received ≤ 3 follow-up calls (OR=2.01; P=0.01) despite the gaps in follow-up calls due to the COVID-19 outbreak. Other significant predictors of adherence were baseline adherence trajectories, number of other medications on the index date, prevalent users, regimen complexity, and CMS risk score.

CONCLUSIONS: At 1 year, patients who received ≥ 4 calls had significantly better adherence than controls. MI intervention by pharmacy students has been demonstrated to improve adherence on a long-term basis.