Approved Research

Validation of two dementia risk scores: the revised ANU ADRI and a new risk assessment tool (CogDrisk).

Lay summary

Dementia is a global health priority. With population ageing there is an increase in number of dementia cases which is expected to reach 152 million cases by 2050 (World Alzheimer's Report 2018). With no effective treatment, the focus has shifted towards preventing or delaying onset of dementia. Dementia risk scores aim at identifying individuals at high risk of developing dementia. The aim of this project is to validate two dementia risk tools, the revised ANU-ADRI and the CogDrisk on mid-life cohort studies such as the UK Biobank and Whitehall II study. These risk scores have been validated in late-life studies. As there are mid-life specific risk factors like obesity, overweight and high cholesterol which could not be accounted for in the calculation of the risk score in late-life studies, we are now interested to validate these risk scores in mid-life studies. We hypothesise that the two risk scores will be valid and that the revised ANU ADRI will accurately predict Alzheimer's disease while the CogDrisk will accurately predict both dementia and AD cases.

This research is anticipated to take up to 18 months to complete. The CogDrisk will be used by clinicians, public health officials and researchers to evaluate dementia risk at the individual and population level. We anticipate that the CogDrisk tool will encourage people to adopt and maintain healthy behaviours, ultimately helping them to reduce the incidence and associated burden of dementia in the long-term.

Scope extension:

We have previously developed a risk score-based prediction model to predict the risk of Alzheimer's disease (AD) known as the ANU-ADRI (Anstey et al., 2013; Anstey et al., 2014). With improvement in study methodology more evidence on dementia risk factors has been published which need to be incorporated in existing risk scores. Hence, we have revised the ANU ADRI and developed a new risk assessment for dementia and AD called the CogDrisk tool (unpublished work). In this study, we would like to validate these two risk tools on mid-life cohort studies (the UK Biobank and the Whitehall II study). These risk tools include midlife risk factors such as high cholesterol, obesity which are not accounted in the risk score calculation when validating against late-life cohort studies. We hypothesise that the revised ANU-ADRI and the CogDrisk will accurately predict AD and dementia in mid-life cohort studies.

The aims of the study are:

1) Validation of the revised ANU-ADRI against the UK Biobank and the Whitehall II cohort study to predict AD.

2) Validation of the new risk assessment tool (CogDrisk) against the UK Biobank and Whitehall II cohort study to predict dementia and AD.

In addition, we would like to use the UK Biobank data to 1) Validate a recent risk tool called DemNCD Risk Tool (submitted study protocol to BMJ Open and main development manuscript under preparation) for predicting dementia and cardiovascular-related non-communicable diseases such as stroke, diabetes, and myocardial infarction. This tool has been developed by pooling 10 well-known international datasets from Australia, the Netherlands, Singapore, the UK, and the USA.  2) To develop a midlife version of the DemNCD risk tool by using midlife participant data from UK Biobank.