A randomized trial of special packaging of antihypertensive medications

Abstract

This article reports a randomized controlled trial designed to test the effects of special packaging of antihypertensive medication on compliance and blood pressure control. One hundred eighty subjects who had exhibited elevated blood pressure greater than 90 mmHg in the two years prior to the study were recruited from patients receiving care at a community hospital-based family medicine practice. After completing preenrollment interviews and blood pressure measurements, subjects were randomly assigned to receive their antihypertensive medications either in the usual vials or in special unit dose-reminder packaging. Follow-up interviews, pill counts, and blood pressure measurements were performed at three-month intervals. There were no statistically significant differences between the control and experimental groups with regard to age, sex, race, employment, education, marital status, insurance coverage, or blood pressure regimens. Prior to the intervention, the experimental group had slightly lower diastolic blood pressure and reported better compliance than the control group. Analyses performed on 165 subjects completing the first follow-up visit revealed no significant improvements in blood pressure control or compliance for patients receiving special medication packaging. While some patients found it easy to remember to take pills packaged using this format, they also found the packages somewhat more difficult and inconvenient to use. In contrast to previously reported work, this study did not demonstrate any significant improvement in compliance with special packaging of antihypertensive medications.