Factors Affecting Medication Adherence in Hypertensive Patients

BACKGROUND: Adherence to medication is a critical factor in the continued health and well-being of patients with hypertension. Patients' acceptance of medical advice and information may be influenced by their subjective beliefs about their health condition; therefore, it is essential that their beliefs be taken into account when giving health advice or medical treatment. OBJECTIVE: To determine whether a relationship exists between illness attribution, perceived control, and adherence to antihypertensive medications. METHODS: A prospective, cross-sectional survey of hypertensive patients was conducted at the University of Michigan Medical Centers, Hypertension Clinic, Ann Arbor, MI. One hundred two patients with a goal to reduce their blood pressure were included in the study. Written and follow-up telephone survey questions assessing patients' illness attributions, perceived control, and medication adherence were administered. Associations between these variables were analyzed using correlation analyses. RESULTS: The majority of patients (67.7%) were adherent with their hypertensive medications. Patients indicated that modifiable variables were the most common attribution believed to cause hypertension; however, there was no significant relationship to medication adherence. A significant inverse relationship was found between perceived control over hypertension and medication adherence (p < 0.01). CONCLUSIONS: The findings suggest that patients' greater perception of control over trying to reduce blood pressure may result in decreased reliance on medications and subsequent nonadherence to drug therapy. Implications of these findings on pharmacy practice are discussed.