Adherence to Medications After Heart Attack Critical

Patients need to achieve high levels of adherence to all the medications they are prescribed after a heart attack in order to reduce their risk of subsequent adverse cardiovascular events, a new study finds.

Numerous studies have demonstrated the importance of medication adherence in improving patient outcomes, but new research suggests that adherence is even more critical in heart attack patients. The results of the study found that after a heart attack, only those patients who correctly took all of their medications had improved outcomes when compared with non-adherent patients.

When patients are discharged from the hospital after a heart attack, they are typically prescribed 4 or more new medications that they will need to take for the rest of their lives. Given the complexity of their drug regimens, patients often struggle with long-term adherence. The study, published online on October 17, 2013, in the American Heart Journal, analyzed data from the Myocardial Infarction Free Rx Event and Economic Evaluation (MI FREEE) Trial to assess the level of adherence needed to improve outcomes and whether adherence to all medications is necessary in these patients. In the MI FREEE trial, researchers analyzed the effect of copayments on adherence to beta-blockers, statins, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers prescribed to patients after heart attacks.

For the current study, patients who received free medication in the trial and who had filled a prescription for at least 1 of the trial medications were classified as adherent, partially adherent, or non-adherent to each of the medications based on the portion of time the drug was available to the patient. Patients were considered adherent if they achieved 80% or greater coverage, partially adherent if their coverage ranged from 60% to 79%, and non-adherent if their coverage was under 60%. The researchers then evaluated the relationship between medication adherence and readmission for a major vascular event, including fatal or nonfatal acute heart attack, unstable angina, stroke, and congestive heart failure, or coronary revascularization, including coronary bypass, stenting, and angioplasty. Trial patients who did not receive free medications were used as controls.

The results indicated that patients who achieved adherence of 80% or greater to each of their prescribed medications were significantly less likely to experience a major vascular event or undergo revascularization when compared with controls, while non-adherent and partially adherent patients had event rates similar to control patients. Adherent patients were 24% less likely to experience an event compared with control patients.

The researchers conclude that all recommended therapies are necessary in patients after heart attack and that improved adherence to each drug reduces the risk of subsequent major cardiovascular events. The results of the study highlight the importance of adherence and the need for more interventions to improve adherence among these patients.

“[I]nterventions that simplify treatment regimens, remind, and motivate patients about the importance of taking their therapies as prescribed, may hold substantial promise and should be explored further,” the researchers write.