Losing our minds — an AU$85bn phenomenon

There is a perfect storm brewing, largely unnoticed, in the 21st century: the convergence of two high-prevalence, high-impact and growing groups of brain conditions — mental illness and dementia.

While previously these conditions were studied in silos, recent medical research has uncovered a growing body of evidence revealing strong links between the two.

It is still uncertain exactly what is cause and what is effect, but what is known is that we are losing our minds at an unprecedented rate and scale. And not just in Australia.

Neuroscience has taught us that above all else, it is the health of our brains that will determine our trajectory through life and particularly as we age. Currently, one in five Australians suffers from a mental health disorder during their lifetime, ranging from depression and anxiety, through to psychotic illness such as schizophrenia or bipolar disorder.

According to the Australian Institute of Health and Welfare, for every 1000 Australians, one in 15 is affected by a form of cognitive impairment — Alzheimer’s disease and vascular dementia representing the most common causes.

The latest WHO statistics indicate that globally, more than 970 million people live with a mental health disorder and 55 million have dementia; 60% of the latter live in middle- to low-income countries.

The Western Pacific region, which comprises 37 countries including Australia, houses the largest and fastest-growing aging population in the world, which will account for more than 50% of global dementia cases by 2050.

Our growing understanding of the interconnectedness of mental health and dementia presents an opportunity to channel this perfect storm and explore novel approaches to prevention, risk reduction, early diagnosis, treatment and care to provide benefits not just to Australia, nor the Western Pacific, but more globally.

Families share conditions that affect the brain and the mind. For instance, conditions such as bipolar disease, schizophrenia and autism are more common in the families of people diagnosed with dementia.  In turn, that may suggest that psychiatric therapies such as lithium may be useful to treat dementia. And conversely, monoclonal antibody therapies for dementia which treat inflammation in the brain may yet be successfully introduced for psychosis.

On 17 September, Neuroscience Research Australia (NeuRA) and The Lancet Regional Health – Western Pacific launched a Dementia Series: global reviews of the best scientific and clinical evidence in order to provide a roadmap for the region.

For example, depression and hearing loss have now been added to the list of modifiable risk factors for dementia. Other key risks previously identified include hypertension, obesity, tobacco use, alcohol intake and physical inactivity. The Lancet Commission asserts today that 45% of dementia cases (an increase on prior estimates) could be delayed or reduced if modifiable risk factors were addressed.

Meanwhile, the Productivity Commission calculated that the direct economic costs of mental illness range up to AU$70 billion a year in expenditure and reduced economic productivity.  Separately, Dementia Australia estimated the total economic cost of dementia as AU$15 billion a year. If we worked to address both health issues in tandem, we may potentially solve an annual AU$85 billion problem. And these figures do not take into account the direct and indirect impacts of mental illness and dementia on the individuals affected and their carers.

As one of the few high-income countries in the Western Pacific, Australia is well placed to step up and adopt a leadership position to reduce the rate and scale of mind loss.

Australia’s National Dementia Plan can help guide similar initiatives across the Western Pacific, to collectively address the burden of depression and dementia in a fashion that is culturally appropriate and engages local communities. A key priority relates to prevention, and to education: as a region, we must develop education programs to target modifiable disease risk factors, with a specific focus on depression.

Allied to education is a need to accelerate diagnostic capacity, while further integrating models of care for both depression and dementia, tailored to the diverse cultural and ethnic groups in the region and expanding supportive services for carers. To achieve these goals, we must close existing research gaps by focusing on the diverse populations within our region. In the face of this need, we must address an imbalance whereby dementia research accounts for less than 3% of the total global health research output.

One of the most alarming findings of the forthcoming series to be published in The Lancet Regional Health – Western Pacific is that across the region, there are many low- to middle-income countries and cultures where brain impairment is simply accepted as a normal part of aging. And further, that families expect to bear the burden of care. In so doing, they inadvertently liberate governments, healthcare systems, industry and research enterprises from their responsibility to address the problem.

In a new take on the old African proverb “It takes a village to raise a child”, investment in multi-sectoral, collaborative consortia will be required — at both national and international levels — to reduce the cognitive impairments induced through dementia and mental illness. Science has opened the door for us; now we must support global approaches so that we may collectively walk through it, together, but always listening to, and being guided by, the consumer voice: people with lived experience and their carers.

What can you do?

For those of us working in the health, mental health and aged care spaces, there are immediate steps we can take to help turn the tide on the growing prevalence of both mental illness and dementia. We can continue to improve our understandings for these conditions and their interconnectedness. We can listen to our patients and communities. We can support people to understand modifiable risk factors.

We can support them to test their hearing and blood pressure; and tackle their diabetes, harmful use of alcohol, smoking, obesity, physical inactivity, depression and social isolation.  In fact, a 20% reduction in exposure to diabetes, hypertension, obesity, physical inactivity, depression, smoking and low educational attainment would result in a 15% reduction in Alzheimer’s disease by 2050.

New treatments for dementia are coming. It is anticipated that monoclonal antibody therapies directed against amyloid, currently under review by the Australian Therapeutic Goods Administration, will become available for Alzheimer’s disease in the coming 12 months.

Research into these growing brain diseases, new treatments and the connections between them is continuing. In the meantime, we need to ensure we’re taking a holistic and multidisciplinary approach to care, with clinicians, nurses, psychologists and allied health care working together to support people with mental illness and those with dementia.

*Professor Matthew Kiernan AM is NeuRA’s Chief Executive Officer and Institute Director. Kiernan is a distinguished clinical academic and scientist renowned for his expertise in neurodegenerative diseases, particularly motor neuron disease (MND) and frontotemporal dementia (FTD).

Prior to joining NeuRA, Kiernan served as Co-Director of the Brain and Mind Centre since its inception in 2015.

He earned his PhD at UNSW Sydney and completed his specialty training at Prince of Wales and Prince Henry Hospitals. In 2015, he was elected as a Fellow of the Australian Academy of Health and Medical Sciences and received the prestigious Order of Australia in 2019 for his remarkable contributions to medicine and medical education in the field of neurology.

In 2022, Kiernan became the recipient of the esteemed Sheila Essey Award from the American Academy of Neurology.

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