The feasibility of a multidomain dementia risk reduction randomised controlled trial for people experiencing cognitive decline: the Body, Brain, Life for Cognitive Decline (BBL-CD)

Objectives: To evaluate the feasibility of a proof-of-concept multidomain dementia risk reduction intervention. Method: An 8-week, parallel-group RCT, focused on increasing adherence to lifestyle domains of Mediterranean diet (MeDi), Physical Activity (PA), and Cognitive Engagement (CE). Feasibility was evaluated against the Bowen Feasibility Framework objectives of: Acceptability of the intervention, compliance with the protocol, and efficacy of the intervention to change behaviour in the three domains of interest. Results: High acceptability of the intervention was demonstrated through a participant retention rate of 80.7% (Intervention: 84.2%; Control: 77.4%). Compliance to the protocol was strong with 100% of participants completing all educational modules and all MeDi and PA components, with 20% compliance for CE. Linear mixed models demonstrated efficacy to change behaviour through significant effects of adherence to MeDi (χ2 = 16.75, df = 3, p <.001) and CE (χ2 = 9.83, df = 3, p =.020), but not PA (χ2 = 4.48, df = 3, p =.211). Conclusion: Overall the intervention was shown to be feasible. Recommendations for future trials in this area are: The implementation of practical, one-on-one sessions as they are more effective than passive education at eliciting behaviour change; use of booster sessions to increase likelihood of lifestyle changes being sustained; and collection of qualitative data to identify barriers to change.