Zidovudine adherence in persons with AIDS: The relation of patient beliefs about medication to self-termination of therapy

OBJECTIVE: To examine the relation of patient beliefs about medication usage and adherence to zidovudine (ZDV) therapy in persons with AIDS. DESIGN: Face-to-face interviews were used to determine attitudes of persons with AIDS toward ZDV and other prescribed medications, history of ZDV usage, and sociodemographics. SETTING: A public hospital infectious disease clinic, an AIDS day care program, and an inpatient unit in a voluntary hospital where care was provided cooperatively by staff and an informal-care partner. PATIENTS/PARTICIPANTS: One hundred forty-one people with the acquired immunodeficiency syndrome agreed to be reinterviewed as part of a longitudinal, New York City-based study examining outcomes related to quality of life. Initial recruitment procedures were to approach all active AIDS patients at each of the three sites between January and July of 1992; reinterviews, which were conducted an average of 6 months later, occurred from mid-1992 through May of 1993. MEASUREMENTS AND MAIN RESULTS: The Zidovudine Drug Attitude Inventory was used to assess subjective feelings and attitudes concerning ZDV and prescribed medications in general. Respondents were grouped into five categories on the basis of their ZDV usage history: (1) 'short-term' users (i.e., those who had been taking ZDV for 25 months or less); (2) 'long-term' users (i.e., those who had been taking ZDV for more than 25 months); (3) self-terminated users: (4) doctor-terminated users; and (5) never users. Long-term users were likely to view ZDV as an illness prophylactic. In contrast, self-terminated users and never users were most likely to believe that ZDV caused adverse side effects and that medicine need not be taken as prescribed. CONCLUSIONS: Patients' beliefs about ZDV were significantly associated with adherence-related behavior. In particular, those who had self-terminated ZDV treatment believed that taking the drug was harmful, were skeptical of its ability to prevent illness, and felt that physicians' directives about medication usage in general could be disregarded. These findings highlight the importance of educating patients about ZDV and of establishing regular patient-clinician exchanges concerning patients' experiences with and beliefs concerning ZDV.