Addressing Dementia Through Analysis of Population Traits and Risk Factors (ADAPTOR) using Australia’s largest cohort study: a study protocol

Abstract Background Dementia is a leading cause of disease burden in Australia, with almost half a million people living with dementia and a steady increase over time in dementia-related deaths. Strengthening the evidence base for dementia risk factors is critical for an effective and efficient public health and policy response. However, the number of Australians with dementia remains unknown, and there are significant gaps in the knowledge on risk factors in the Australian context. In this study we aim to develop reliable data on dementia incidence in Australia and investigate the associated risk factors, using a large population cohort. Specifically, we will assess the relative contribution of risk factors to dementia incidence as a basis for strengthening dementia prevention efforts. Methods We will use data from the 45 and Up Study that includes 267,358 residents of New South Wales, Australia, aged over 45 years, recruited between 2006-2009. To identify dementia cases we will link data from the 45 and Up Study with multiple health datasets containing information relevant to dementia case identification. We will estimate age- and sex-specific dementia incidence and model the association between dementia and risk factors related to socio-demographic characteristics, health conditions and health behaviours. We will also estimate the impact of various modifiable exposures on dementia incidence. Based on the results, we will produce a series of knowledge translation products providing advice on the contribution of identified risk factors to dementia incidence in Australia. Discussion Linking the 45 and Up Study data to multiple health datasets provides a unique opportunity to explore the role of risk factors on dementia incidence, including modelling the effect of modifiable risk factors on dementia incidence in the Australian population. We anticipate the results from this study to guide targeted and gradated strategies for population-level dementia prevention.