Impact of the Chronic Care Model on medication adherence when patients perceive cost as a barrier

Aims: Cost burdens represent a significant barrier to medication adherence among chronically ill patients, yet financial pressures may be mitigated by clinical or organizational factors, such as treatment aligned with the Chronic Care Model (CCM). This study examines how perceptions of chronic illness care attenuate the relationship between adherence and cost burden. Methods: Surveys were administered to patients at 40 small community-based primary care practices. Medication adherence was assessed using the 4-item Morisky scale, while five cost-related items documented recent pharmacy restrictions. CCM experiences were assessed via the 20-item Patient Assessment of Chronic Illness Care (PACIC). Nested random effects models determined if chronic care perceptions modified the association between medication adherence and cost-related burden. Results: Of 1823 respondents reporting diabetes and other chronic diseases, one-quarter endorsed intrapersonal adherence barriers, while 23% restricted medication due of cost. Controlling for age and health status, the relationship between medication cost and CCM with adherence was significant; including PACIC scores attenuated cost-related problems patients with adequate or problematic adherence behavior. Conclusions: Patients experiencing treatment more consistent with the CCM reported better adherence and lower cost-related burden. Fostering highly activated patients and shared clinical decision making may help alleviate medication cost pressures and improve adherence.