Beyond individual-level approaches to dementia prevention: a socioecological reappraisal.

Dementia prevention has largely focused on modifying individual behavioural and clinical risk factors. Although this approach has advanced understanding of dementia risk, it could under-recognise the broad social, environmental, and structural conditions that shape brain health across the life course. In this Viewpoint, we apply the socioecological model, a well established public health framework, to map 61 modifiable dementia risk and protective factors identified in the published population-attributable fraction literature across four levels of influence: individual, interpersonal, community, and societal. Most mapped factors (49/61 [80%]) were at the individual level, with few at interpersonal (2/61 [3%]), community (3/61 [5%]), or societal (7/61 [11%]) levels. This pattern suggests that the published evidence base remains predominantly organised around individual-level factors despite growing recognition of upstream influences. We argue that effective dementia prevention requires coordinated action across sectors, including education, urban planning, environmental policy, and health care.