Barriers to medication adherence in patients prescribed medicines for the prevention of cardiovascular disease: a conceptual framework.

OBJECTIVES: To identify barriers to medication adherence in patients prescribed medicines for the prevention of cardiovascular disease and map these to the Theoretical Domains Framework (TDF), to produce a conceptual framework for developing a questionnaire-based medication adherence tool.

METHODS: A scoping review of barriers to medication adherence in long-term conditions was conducted to generate an initial pool of barriers. After preliminary mapping to the TDF, these barriers were presented to two focus groups of patients prescribed medicines for the prevention of cardiovascular disease (n = 14) to stimulate discussion. The group discussions enabled the patients' interpretations of the adherence barriers to be determined, provided validity from the patient perspective and identified additional barriers unrepresented in the scoping review.

KEY FINDINGS: The preliminary pool of adherence barriers was identified from 47 studies across a range of long-term conditions. The majority of TDF domains were represented by these literature-identified barriers except 'social/professional role and identity' and 'behavioural regulation'. Barrier mapping was largely endorsed by focus group participants, who also contributed additional barriers, including those relating to not having a 'system' in place for managing their medicines and the negative emotions evoked by medicine taking.

CONCLUSION: The TDF enabled full exploration of adherence barriers including those relating to emotions which have received limited attention in the literature. This work has provided a conceptual framework for developing a questionnaire to identify an individual's adherence barriers which may then be coupled with appropriate behaviour change techniques to deliver a theory-based intervention tailored for individual need.