Process evaluation of the impact and acceptability of a polypill for prevention of cardiovascular disease

Importance: The Use of a Multidrug Pill In Reducing cardiovascular Events (UMPIRE) trial has shown improved adherence with the use of a polypill strategy when compared with usual medications for cardiovascular disease (CVD) prevention. To advance from efficacy to impact, we need a better understanding of why and how such a strategy might be deployed in complex health systems. Objective: To understand, from the perspective of UMPIRE trial participants and professionals, how and why a polypill strategy improves adherence compared with usual care, why improvement is greater in some subgroups, and to explore the acceptability of a polypill strategy among trial participants and healthcare professionals. Design, setting and participants: A preplanned process evaluation, based on qualitative interviews, was conducted with a subsample of 102 trial participants and 41 healthcare professionals at the end of the UMPIRE trial in India and Europe. Results: Most patients contrasted the simplicity of the polypill with usual medications that they found complex and, for many in India, expensive. Patients with low baseline adherence struggled most with complex medication lists, and those without established disease described less motivation to adhere when compared with people who had already been diagnosed with CVD; people in the latter group had already undertaken self-directed measures to adhere to CVD preventive medicines prior to entering the trial. Taking medication was one of many adaptations described by patients; these included dietary changes, stopping smoking and maintaining exercise. Most patients liked the polypill strategy, although some participants and health professionals were concerned that it would provide less tailored therapy for individual needs. Conclusions: Adherence to treatment lists with multiple medications is complex and influenced by several factors. Simplifying medication by using a once-daily polypill is one approach to CVD prevention that may enhance adherence. Prescribers should also consider the wide variety of adjustments that individuals need to make to cope with daily medication.