A qualitative investigation of the modifiable determinants of medication adherence in bipolar disorder (BD): Views of patients and their family and friends

Background: Medication nonadherence in bipolar disorder (BD) can lead to adverse outcomes including relapse, hospitalisation and suicidility. Adherence research traditionally excludes mental health populations and their family and friends, contributing to inequity between physical and mental health. We used behavioural science to characterise modifiable adherence determinants in BD from the perspectives of patients and their family and friends. Method: Between April-June 2020, we conducted two focus groups and 26 interviews with adults with BD and their family and friends. We explored modifiable adherence determinants which were mapped to the Theoretical Domains Framework (TDF), followed by a thematic analysis and prioritisation of determinants. Results: Sixty-three (including 13 new) adherence determinants, mapped to nine TDF domains, were prioritised. Four themes of adherence determinants emerged: the medication itself; practicalities; how patients perceive themselves, their illness, and treatments; and collaboration between patients, their family and friends, and healthcare professionals. Nine prioritised TDF domains were: ‘Environmental context and resources’, ‘Intentions’, ‘Emotion’, ‘Social Influences’, ‘Goals’, ‘Memory, attention and decision processes’, ‘Beliefs about consequences’, ‘Knowledge’ and ‘Social/professional role and identity’. Respective examples include side effects, treatment preferences, fear of not being ‘myself’, relationships with healthcare team, medication affecting life goals, forgetfulness, beliefs about negative consequences, not knowing the risk of stopping medication, and involvement in treatment decisions. Conclusion: Targeting antecedents of forgetfulness as well as newly identified determinants linked to ‘Emotion’ and ‘Intentions’, may improve adherence. Mapping adherence determinants to TDF domains provides a framework for designing personalised adherence interventions by selecting appropriate behaviour change techniques.