Addressing global diversity in dementia research with the COSMIC collaboration.

There is a need to study dementia risk factors more equitably across high-income countries (HICs) and low- and middle-income countries (LMICs). Cohort Studies of Memory in an International Consortium (COSMIC) is doing this by bringing together cohort studies of cognitive ageing from around the world to study dementia risk factors in a truly international way. COSMIC researchers have investigated a wide range of dementia risk factors across the diverse member studies and shown that some factors have different levels of association with dementia in different regions and populations. These differences include some cardiovascular and lifestyle factors having stronger associations with cognitive decline and dementia among Asian people than among White people. Conversely, more social factors were associated with reduced chances of mild cognitive impairment or dementia among Asian people than among White people. Interventions to prevent or delay dementia will require tailoring to optimise the local effect. COSMIC is currently developing methods to reliably assess dementia from limited data in under-resourced regions, producing dementia risk models appropriate for LMICs, and increasing its attention to genetics, biomarkers, and environmental factors across diverse regions and populations. Further, COSMIC is helping to train new researchers in LMICs, and COSMIC members are among the first to be boarded on Dementias Platform Australia, a secure data exchange platform facilitating cohort study data access by researchers anywhere in the world. We invite cohort studies from LMICs or under-studied populations to join COSMIC and help make dementia research as globally representative and collaborative as possible.