Study finds that initiatives to improve medication adherence after myocardial infarction do not work

Kevin G Volpp

Kevin G Volpp (Center for Health Incentives & Behavioral Economics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA) and others report in JAMA Internal Medicine that a compound intervention involving wireless pill bottles, lotter-based incentives, and social support did not significantly improve patient adherence to medication regimens after an acute myocardial infarction. Volpp talks to Cardiovascular News about the need to improve medication adherence in post-acute myocardial infarction patients and the difficulties in achieving this.

What percentage of post-acute myocardial infarction patients do not adhere to their medication regimens?

About 55–60% (40–45% are adherent). This is based on the assumption that patients should all be on a set of cardiovascular medications post-acute myocardial infarction. Our numbers are very similar to those found by Chouhdry et al in 2011 (published in the New England Journal of Medicine).

What are the key reasons for poor adherence?

There are a myriad of factors that can contribute to poor adherence. Patients may stop taking their medication once they feel better, even though patients with a chronic illness—such as acute myocardial infarction—need to take medications for the rest of their lives. Some patients do not like taking medicine and feel that taking medicine is a daily reminder that they have an ongoing illness. The medications may cause side-effects or perceived side-effects. There are also issues of cost, and sometimes people are just forgetful and forget to take their medication.

What were the interventions used in your study?

  • Remote monitoring with the use of up to four electronic pill bottles
  • Daily lottery based financial incentive to reward medication adherence
  • Social support from a friend or family member, who would be notified if patient was non-adherent for a specific amount of time
  • Access to social work resources
  • Engagement with study staff to provide monitoring, feedback and reinforcement of adherence.

Why do you think the interventions did not appear to increase adherence?

We enrolled participants through insurance carriers, identified through their claims, which caused a delay between time of discharge and enrolment. It is possible that if we had been able to engage these patients earlier—for example, as a hospital-based intervention—and we could reach them at the time of discharge, then we might have had a greater opportunity to influence these patients and change the course of their care. Our limitations section identifies some other potential reasons.

Looking to the future, what interventions do you think have the potential to increase adherence?  Any future research or intervention will need to have a combination of thinking about the benefit design, the provider-patient interactions, the health plan, and overall how we can more strongly support patients in their efforts to be healthy. My colleagues and I look at these issues through the lens of behavioral economics, and are conducting studies to see how behaviourally-informed interventions may increase medication adherence in a variety of contexts.

If interventions are going to be used to increase adherence, what are the cost considerations (i.e presumably, they have to be cost-effective as well as effective)?

Cost is a huge consideration. These patients on average cost about US$30,000 in the year following the heart attack, but more importantly are at risk of having other heart attacks or other hospital readmissions later on. We did see a lower cost in our intervention of US$24,000 vs. US$29,800 in the control group, but the difference was not statistically significant.

Based on the available data, what can doctors do to encourage medical adherence?

Enrolment of patients immediately post discharge may be the critical ingredient that our study missed. We could imagine a healthcare system running this kind of intervention, especially since they may be able to reach patients immediately post discharge.