What people think about medicines : the relationship between medication beliefs and adherence to antidepressant therapy : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University

Abstract

Major depressive disorder is a common mental disorder seen in primary care and treatment with antidepressant medication has been shown to be an effective treatment. Non-adherence to treatment regimens is considered by many to be the most serious challenge facing medical practice today. Research on medication adherence has more recently shifted its focus to the cognitive factors (i.e., patient beliefs) that determine adherence. Prior research has shown that pre-treatment perception of benefits and barriers to medication predict initial medication adherence. To contribute to this emerging literature, the present study assessed 85 depressed primary care patients about their beliefs in the necessity for and concerns about antidepressant therapy, and reported adherence using validated questionnaires (BMQ, Home, Weinman, & Hankins, 1999; MARS. Home & Weinman, 2002). The results of the present study showed no relationship between patient beliefs about the necessity of antidepressant therapy for their health and reported adherence. As predicted, participants holding stronger concerns about the potential adverse effects of the medication and stronger necessity beliefs, compared to concerns beliefs, reported increased rates of adherence. Depression severity was found to be associated with reported adherence, but was independent of the relationship between medication concerns and adherence. The present study replicated previous research and added further support for the theoretical basis of medication adherence by showing that there are similar theoretically based, determinants of adherence among patients with chronic physical health issues and those with mental health issues.