Trajectories of adherence to ACEI/ARB medications following a motivational interviewing intervention among Medicare Advantage beneficiaries in Texas.

Objectives: To assess the impact of student telephone motivational interviewing intervention on angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (ACEI/ARBs) adherence trajectories and identify predictors of each trajectory.

Methods: The intervention group included continuously enrolled Medicare Advantage Plan patients non-adherent to ACEI/ARBs vs the control group (1:2 ratio). The intervention was tailored by pre-intervention trajectories and included an initial and five follow-up calls. Adherence was measured 6 months after initial calls using the proportion of days covered (PDC). Monthly PDCs were integrated into a group-based trajectory model and categorized patients into 4-groups. A multinomial logistic regression model was used to evaluate trajectory predictors.

Results: The study comprised 240 intervention patients and 480 controls with four trajectories: adherent trajectory 44.2%, gradual improvement in adherence 13.4%, slow decline in adherence 24.1%, and discontinuation 18.3%. Patients with the intervention were less likely to experience a slow decline in adherence than controls (OR: 0.627 [0.401-0.981]). Patients with specialty prescribers' visits, ≥ 1 previous hospitalization, rapid decline in adherence as pre-intervention trajectory, and higher CMS risk score were associated with discontinuation trajectory.

Conclusion: Intervention patients vs controls had a lower likelihood of following a slow decline in adherence pattern.

Practice Implications: This study underscores the importance of individualized interventions and the association between past adherence patterns and post-intervention trajectories.