Community-based interventions for cognitive health in older adults: a scoping review

The global prevalence of dementia was projected to almost triple from 2019 to 2050, imposing major health, social, and economic burdens. With limited pharmacological options, interventions targeting modifiable risk factors in community settings may help delay or reduce cognitive decline. Evidence of their effectiveness and feasibility for large-scale implementation, however, remains fragmented. This scoping review synthesised evidence on community-based interventions for promoting cognitive health in older adults, examining intervention domains, cognitive outcomes, and implementation barriers and strategies. The review followed Arksey and O’Malley’s methodological framework. Five databases and supplementary sources were searched for studies published between 2014 and 2025. Eligible studies examined single- or multi-domain community-based interventions targeting older adults (≥ 60 years) without dementia at baseline. Data extraction captured intervention characteristics, cognitive outcomes, and implementation-related findings. Barriers were mapped using the Practical, Robust Implementation and Sustainability Model (PRISM), and implementation strategies were classified according to the Expert Recommendations for Implementing Change (ERIC) taxonomy. Eighty-two studies were included. Interventions addressed single domains (n = 43; mainly physical activity or cognitive training) or multiple domains (n = 39; commonly combining physical activity and cognitive components, with additions such as nutrition, vascular risk management, or social engagement). Cognitive outcomes varied, with some studies demonstrating significant improvements and others showing mixed or null effects. Reported implementation barriers included intervention complexity, participant burden, limited organisational capacity, and contextual challenges related to accessibility and community awareness. Twenty-seven unique strategies were identified across pre-, during-, and post-implementation phases. Community-based interventions hold promise for promoting cognitive health in older adults, yet evidence of consistent effectiveness remains limited, and implementation processes are often underreported. Strengthening the integration of implementation science within future studies—while addressing contextual and system-level barriers—may enhance scalability, sustainability, and equitable reach of such programmes.