A Randomized Controlled Trial to Improve Medication Compliance Among Patients With Coronary Heart Disease

Coronary heart disease (CHD) is the most common cause of death in the United States. A common term for CHD is "blocked arteries." People with CHD or "blocked arteries" often have high blood pressure, high cholesterol, or diabetes. They are also more likely to suffer a heart attack. Many heart attacks could be prevented by taking medicines that control blood pressure, cholesterol, and diabetes. However, only 50%-60% of patients take their medicines as directed. Patients who don't take their medicines regularly are considered noncompliant.

One of the risk factors for noncompliance is low health literacy. Health literacy is the ability to obtain, understand, and act on basic health information. Patients with low health literacy may not understand their illnesses as well, or how to take their medicines properly.

The purposes of this project are

1. to learn more about the relationship between low health literacy and medication compliance, and
2. to test 2 different strategies designed to help patients take their medicines more regularly.

Patients with CHD were recruited when they arrived for a regular doctor’s appointment. We measured their health literacy skills, asked questions about how they take their medications, and checked their blood pressure and last cholesterol and diabetes measurements. We then assigned patients to 1 of 4 intervention groups (intervention ongoing). The first group is receiving usual care, which includes regular medication instructions printed on the bottle and no reminders to refill medicines. The second group gets monthly postcards reminding them to refill their prescriptions. The third group gets a new medication schedule that shows them, with pictures and figures, how they are supposed to take their medicines each day. The fourth group receives both the postcards and the new medication schedule. We are following patients for 1 year to see which intervention has the greatest impact on their medication compliance, blood pressure, cholesterol, and diabetes measurements. We will also examine whether patients’ health literacy affects the success of the interventions.