Using the theoretical domains framework to determine the barriers and facilitators to medication adherence in Parkinson's disease

BACKGROUND: Patient medication adherence in Parkinson's Disease (PD) is often suboptimal. This may lead to poor symptom management, greater disease burden, decreased quality of life and increased healthcare costs. Use of psychological theory such as the Theoretical Domains Framework (TDF) has effectively captured barriers and facilitators to medication adherence in other long-term conditions. Applying this framework to medication adherence in PD could provide a better understanding of the challenges to inform the development of effective interventions. OBJECTIVES: The aim of the study was to apply the TDF to determine the barriers and facilitators to medication adherence in people with PD. METHODOLOGY: This qualitative study employed online interviews to explore medication adherence in a small group of people with PD recruited via Parkinson's UK and social media. A semi-structured interview schedule was designed informed by the 14 TDF domains. All interviews were audio-recorded, transcribed verbatim and mapped to the TDF using Framework Analysis. RESULTS: Twelve participants diagnosed with PD were interviewed, 11 of whom were currently taking prescribed medication plus another self-medicating with Vitamin B1. All TDF domains were evident in the data. Predominant facilitators were Domains 1 - Knowledge, 6 - Social Influence, and 12 - Beliefs about Consequences and barriers were 7 - Reinforcement, 10 - Memory, Attention and Decision Processes, and 11 - Environmental Context and Resources. Other themes were not related to medication adherence. CONCLUSION: In this small group, all data relating to the barriers and facilitators for medication adherence in PD were successfully mapped onto the TDF. This indicates the utility of the framework for determining and structuring the factors to consider when providing medication support for this patient population in an accessible and coherent way. Further quantitative studies are needed to determine the extent to which these factors can be generalised to other PD patients.