Neuro Imaging to examine high rates of dementia in older Aboriginal Australians

Early life stress (ELS) has been linked to abnormalities in brain structure and function and may contribute to increased risk of cognitive decline and dementia later in life. ELS has also been associated with the high prevalence of dementia observed in older Aboriginal Australians.

A study at NIF’s UNSW Node, NeuRA Imaging is engaging the Australian Aboriginal community to investigate structural and pathological brain changes that underlie in high rates of dementia and cognitive decline in older Aboriginal Australians.

This will be the first study that investigates neuroimaging in cognitive impairment in older Aboriginal Australians and will inform dementia prevention, diagnosis and policy. It will also contribute to the wider literature on vascular risk in the pathogenesis of Alzheimer’s disease and associated biomedical and social risk factors.

After extensive community engagement with partnering Aboriginal communities including La Perouse, NSW, the initial consultation stage of NeuRA’s Koori Growing Old Well Study indicated that neuroimaging should be included in future dementia studies (Lavrencic et al., 2020, Int Psychogeriatr). Led by NeuRA’s, researchers including Dr Kylie Radford, Professor Tony Broe AM and Dr Louise Lavrencic, the Koori Growing Old Well Study included a community planning survey, pilot MRI study and guidance from an Aboriginal and Torres Strait Islander Steering Committee.

“NIF’s capabilities are allowing this study to investigate underlying brain changes and pathology in ageing and dementia in partnership with Aboriginal communities. The study will give greater detail and is using sophisticated and novel MRI techniques. By having the facility in-house at NeuRA it also means we can ensure a culturally safe and welcoming environment for our participants. With a rapidly ageing population and high rates of dementia, we hope that this ground breaking study will shed light on important ways to promote healthy brain ageing with Aboriginal and Torres Strait Islander peoples,” said Dr Kylie Radford, Senior Research Scientist and Group Leader, Neuroscience Research Australia.

The neuroimaging sub-study is a prospective, cross-sectional non-interventional study where participants will first complete a comprehensive interview and diagnostic assessment as part of the Koori Growing Old Well study. Consenting participants (200) aged 55+ will undergo MR scans with an expected study completion by 2023.

The outcome analyses will include identifying associations between cognitive impairment and hippocampal atrophy/volume and vascular indices on MR. Vascular pathology will be examined for cases of possible or probable Alzheimer’s disease compared to a cognitively intact control group. Correlations between MR measures and early life stress, adult risk and protective factors, cognitive function, and clinically diagnosed cognitive impairment will be investigated.

Better detection and treatment of dementia

Biogen’s Aducanumab (Aduhelm) is the first disease modifying therapy for AD approved by the The United States Food and Drug Administration (FDA). NIF’s positron emission tomography (PET) imaging facilities at the University of Melbourne, HIRF and the Hunter Medical Research Institute (HMRI) supported the Australian trial recruitment of the Biogen Phase 3 trial by screening potentially suitable participants with amyloid PET scans in collaboration with the Australian Imaging Biomarkers and Lifestyle Study of Ageing at the Florey Institute of Neuroscience and Mental Health and Austin Health.

To prescribe the treatment for prodromal and early clinical AD it will be necessary to use imaging both PET and magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF)/blood biomarkers to ensure that subjects being treated have AD and that side effects from Aduhelm are properly managed.

Alzheimer’s disease (AD) is the most common type of dementia making up 70% of all dementia. There are about 300,000 Australians currently living with the disease, with the average disease duration of 10 years equating to 30,000 new cases each year. These numbers are predicted to triple by 2050.

The degeneration within the brain begins two to three decades before overt symptoms, highlighting early detection is critical. NIF’s University of Melbourne Node and the Herston Imaging Research Facility (HIRF) have been involved in several dementia trials, studying different aspects of the disease including early biomarker detection, combining state of the art multimodality imaging, genetics and neuropsychology. NIF is working to assess novel radiotracers as a diagnostic tool for early detection of AD and the development of a national network of radiotracers for dementia screening in collaboration with QTRaCE and the Australia Dementia Network (ADNeT). This research aids the success of new preventative medicines, both through repurposing an existing drug and novel drug development and improves classification of AD subtypes, which impact treatment profiles.

NIF has played a major role in helping Australia to maintain its leadership in imaging applied to the dementias, particularly in AD. This has occurred at multiple sites around the country since 2012. The advent of disease modifying therapies for AD will cause an increase in demand for services and it will be crucial for new innovative and cost effective methods of service delivery in our increasingly ageing population.


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If you have any concerns about heart disease or atherosclerosis, please talk to your GP and check this website.

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