Six years ago, the Koori Growing Old Well Study identified Aboriginal Australians aged over 60 were three times more likely to develop dementia than the overall Australian population.
That same study, also identified Aboriginal Australians were more likely to develop dementia at a younger age than the remainder of the Australian population.
Today that remains the case, as the Koori Growing Old Well Study-II seeks to better understand why dementia prevalence among Aboriginal Australians is so much higher.
The initial Koori Growing Old Well Study looked at rates of dementia among 336 Aboriginal volunteers aged 60-92.
National Health and Medical Research Council - Australian Research Council Dementia Research Fellow, Dr Kylie Radford said advancing age remained the major risk factor for dementia in Aboriginal Australians, as in all populations, but the Koori Growing Old Well Study identified some additional factors associated with dementia, that are potentially modifiable.
“Given that Alzheimer's disease was the predominant type of dementia diagnosed, there is likely to be a number of lifestyle and environmental factors contributing to dementia risk or healthy brain ageing for Aboriginal Australians, as have been found in other populations globally,” Dr Radford said.
“These include looking after cardiovascular health, preventing head injuries, education and mentally stimulating work opportunities and avoiding heavy alcohol use.
“We also found a connection between early life stress and adversity, and late life dementia - so being aware of the possible ongoing effects of childhood trauma and seeking treatment for depression, anxiety, etc. could also be important, along with focusing on supporting families and kids into the future.”
Dr Radford and the Koori Growing Old Well team are still investigating the causes of high dementia rates, but these were the key findings from wave 1, which need to be confirmed longitudinally.
“A follow-up study (Koori Growing Old Well Study-II) is currently underway and will be completed over the coming year with a grant from the Dementia Collaborative Research Centres,” Dr Radford said.
“This study will determine the social and biomedical risk factors for cognitive decline and incident dementia, in parallel to new research focused on healthy brain ageing and funded by the National Health and Medical Research Council.”
Dr Radford said the Koori Growing Old Well Study and other studies such as the Kimberley Indigenous Cognitive Assessment also identified head injury with loss of consciousness, such as traumatic brain injury, as a key risk factor for dementia in both urban and remote Aboriginal populations.
“Head injury with loss of consciousness is emerging as a key risk-factor in urban and remote Aboriginal populations and from the evidence to date, seems to be more important in terms of dementia-risk than lifestyle factors like high alcohol consumption when you were younger,” Dr Radford said.
“There is no association between dementia and current to late-life alcohol consumption in this older population.”
Dr Radford said it was common for past head injuries reported by Aboriginal men of the generation in the study to relate to sports injuries, such as boxing, and this could be contributing to dementia among that group. This will be followed up in the second wave of the Koori Growing Old Well study.
“In different populations where prevalence of head injury is high, it seems to be something that is really lighting up in dementia studies and is something we need to start thinking about, protecting the brain from sporting injury,” Dr Radford said.
Dr Radford said awareness of the issue of dementia for Aboriginal and Torres Strait Islander Australians is continually improving, but there is much yet to be done in terms of understanding causes and risk or protective factors (through further epidemiological research - for dementia prevention) and providing culturally appropriate care and support for Aboriginal people with dementia and their families.
It is hoped the Koori Growing Old Well study and other work taking place in this area can better identify the burden of dementia among Aboriginal and Torres Strait Islander Australians and potentially modifiable risk factors in a bid to inform the development of culturally appropriate and specific risk-reduction programs, treatment and care for Aboriginal and Torres Strait Islander people with dementia.