Abstract
BACKGROUND: Medication non-adherence is a major public health issue, creating obstacles to effective treatment of hypertension. Examining the underlying factors of deliberate and non-deliberate non-adherence is crucial to address this problem. Thus, the goal of the present study is to assess the socio-demographic, clinical and psychological determinants of intentional and unintentional non-adherence. DESIGN AND METHODS: A cross-sectional survey was conducted between March, 2015 and April, 2016. The sample consisted of hypertension patients holding at least one medical prescription (N=109). Measurements assessed patients' medication adherence, health literacy, empowerment, self-efficacy, medication beliefs, and patients' acceptance of their doctor's advice, socio-demographic and clinical characteristics. RESULTS: Patients who occasionally engaged in either intentional or unintentional non-adherence reported to have lower adherence selfefficacy, higher medication concern beliefs, lower meaningfulness scores and were less likely to accept the doctor's treatment recommendations. Patients who occasionally engaged in unintentional nonadherence were younger and had experienced more side effects compared to completely adherent patients. Adherence self-efficacy was a mediator of the effect of health literacy on patients' medication adherence and acceptance of the doctor's advice was a covariate. CONCLUSIONS: Regarding the research implications, health literacy and adherence self-efficacy should be assessed simultaneously when investigating the factors of non-adherence. Regarding the practical implications, adherence could be increased if physicians i) doublecheck whether their patients accept the treatment advice given and ii) if they address patients' concerns about medications. These steps could be especially important for patients characterized with lower self-efficacy, as they are more likely to engage in occasional nonadherence.