Cultural and linguistic adaptation of a personalised post-diagnostic dementia intervention for Bangladeshi families in the UK: an iterative adaptation study

People from UK South Asian communities experience barriers to accessing dementia care. Evidence suggests that evidence-based psychosocial dementia interventions can be successfully adapted for different cultural contexts, but further evidence is needed on how adaptations are developed and refined in practice. We aimed to adapt GRACE-family (Goal diRected, Accessible and Evidence-based Care), an evidence-based, manualised post-diagnostic dementia intervention, comprising 4-8 sessions for family carers and where possible, people with dementia, for Bengali-speaking communities. In a theory-informed process, a co-adaptation group encompassing lived, academic and clinical/professional experience developed consensus regarding which intervention functions were core. They then explored how adaptation might, while retaining these, account for cultural and linguistic contexts, informed by focus groups with memory service and Bengali community organisation staff (n=14). We developed a prototype adaptation, then piloted it with four Bangladeshi families supporting a person with dementia. Post-intervention, participants were asked about goal attainment, intervention acceptability, and qualitatively interviewed. Pilot data and a focus group with Sylheti-speaking family carers informed further refinements (n=6). Across data sources, two themes informed adaptation: (1) stigma, trust and community networks shaped access to dementia support; (2) flexible delivery was needed to respond to diverse language, communication and cultural needs. 3/4 pilot families completed the prototype intervention, which was in English as initial consultation cautioned against developing a written manual in a predominantly spoken language. Participants reported improvement on 7/8 personalised goals set, and all considered the intervention acceptable. Pilot delivery identified challenges using English-language materials during interpreter-mediated sessions. Iterative refinements added standard Bengali materials and spoken Sylheti audiovisual resources to broaden delivery options and facilitator training for culturally responsive and interpreter-mediated delivery. Our co-adaptation approach enabled stakeholders to advise from different, including experiential perspectives. It may inform future approaches to cultural and linguistically adaptations of psychological interventions for minoritised communities.