A longitudinal feasibility study on fostering daily conversation habits centered on perspective taking and time orientations for cognitive health: Protocol for a single-arm intervention in Japanese local communities

BackgroundDementia prevention has the potential to bring considerable benefits in diverse contexts. Conversation requires various cognitive functions and is therefore considered a natural multi-component preventive measure that can be practiced in daily life. Although an emerging line of research supports the potential of conversation-based cognitive interventions, further research is needed to elucidate which elements are effective and through what mechanisms. In addition, given that previous studies have shown that older adults embedded in social networks with a high proportion of non-family members have higher cognitive function, fostering social interactions between older adults with those beyond their family would be beneficial, while assessing the ecological validity of delivering conversation-based program in naturalistic community settings is essential. Furthermore, it remains to be clarified whether participants can integrate lessons from conversation-based programs into their daily routines in a voluntary and sustained manner. This study aims to examine the feasibility of the long-term conversation-based program, with preliminary analyses of its key components for future rigorous effectiveness tests. MethodsThe study is a single-arm longitudinal intervention in a community setting in Japan. Participants will attend monthly sessions over five years, engaging in conversations based on the Coimagination method. The feasibility and adherence are assessed mainly by dropout rates and speech frequencies in sessions, respectively. The primary outcome is verbal fluency, repeatedly improved by previous conversational interventions. The key components of the intervention such as perspective taking and time orientation will also be measured. Preliminary intervention effects will be assessed by the interaction between adherence and time in a mixed-effects model. DiscussionThe study following this protocol is expected to provide insights into the feasibility and ecological validity of our conversation-based program and its barriers, as well as preliminary findings for conducting a future long-term randomized controlled trial to rigorously verify the intervention effects. Because the intervention will be conducted in parallel in two regions, suggestions for external validity are also expected. Trial registrationProspectively registered in the UMIN Clinical Trials Registry (UMIN000057738).