Keeping the mind active

A healthy future for seniors - preventing dementia

Monday, 01 October 2007
By Rebecca Scott
University of Melbourne

Medical research and staying active later in life could hold the key to a healthier future for older Australians, reports REBECCA SCOTT.

Sudoko every night keeps David Solomon’s mind alert – but that is not the only activity that keeps the 77-year-old on the ball. The world-renowned scientist, who co-invented the first plastic bank note, holds some of the world’s most cited patents and is widely honoured and recognised but he is not prepared to rest on his laurels.

At a time of life when many are content to retire, Professor Solomon continues to work as a researcher, one day a week in the University of Melbourne’s Department of Chemical and Biomolecular Engineering. “I am very lucky to be able to stay on in the workforce and contribute to projects,” says Professor Solomon. “If I was not working, I’d have problems. I’d have to do something else. “When you do research you never switch off,” he says. “Even when I am away from the office at my holiday house, I am always trying to solve problems. I guess I have always been interested in how things work.”

Research suggests that by continuing to work, Professor Solomon may be doing more than just indulging in his passion for science – he could also be keeping his brain healthy.

That, combined with a focus on education earlier in life – which saw him study at night school while working for a paint company – may also be a factor.

Professor David Ames, Director of the National Ageing Research Institute at the University of Melbourne, says that people who stimulate their minds early in life have a better chance of warding off dementia. “There is a possibility that the more educated you are, the less likely you are to get dementia,” he says.

“According to the Spare Capacity theory, if the brain is stimulated early in life and more brain cell connections are developed, the extra capacity means that the person can afford to lose some later. “Growing old does not mean someone will develop dementia but the disease does affect one per cent of people aged 60–64 and above 25 pe rcent of people over 85 years old.”

University of Melbourne researchers such as Professor Ames are among an army of scientists worldwide trying to determine what causes some people to develop dementia, while others’ brains remain healthy well into old age.

“The issue of ageing is the largest challenge apart from climate change, facing Australia and the world in the next 50 years,” Professor Ames says.

The percentage of elderly people in the population, currently at 13 per cent, is set to rise. It is expected that by the year 2050 over 25 per cent of the Australian population will be over the age of 65.

Professor Ames says animal studies have proved that more brain cell connections are developed if the brain is stimulated.

An Australian-first longitudinal study into risk factors associated with dementia aims to investigate if the same is true in humans.

The Australian Imaging, Biomarkers and Lifestyle Study of Ageing (AIBL) is a collaborative study between the University of Melbourne, Mental Health Research Institute, National Ageing Research Institute, Neurosciences Australia, Austin Repatriation Hospital, Edith Cowan University and CSIRO.

The $10 million study is investigating lifestyle risk factors such as smoking, high blood pressure, obesity, exercise, social connectedness and education in order to determine the causes of dementia and Alzheimer’s disease. Dementia is a decline in mental function due to brain disease.

Professor Ames says dementia has many different causes, the two most common being Alzheimer’s disease and vascular disease of the brain. Vascular disease is caused by accumulation of fatty deposits in a person’s arteries, which in turn restricts the blood supply to the brain. Research reveals that the risk of getting dementia can be increased by your family history and lifestyle. He says that people who are obese, have high blood pressure, Type 2 Diabetes or smoke will have a marginally increased chance of getting dementia than someone who treats their body well. “We can draw some conclusions about vascular disease being linked to poor health but it is not so easy to determine what causes onset of Alzheimer’s,” Professor Ames said.

Currently 200 000 people (1 per cent of the population) have dementia, by 2050 it is estimated 730 000 – or 2.8 per cent of the population – will have dementia.

Professor Ames says advances in modern medicine have caused the recent increase in dementia. “Because modern medicine has eliminated many of the diseases that used to kill many people, death later in life is increasingly due to dementia,” he says Professor Colin Masters, Executive Director of the Mental Health Research Institute and Laureate Professor in the Centre for Neuroscience at the University of Melbourne, says that early intervention provides a chance to delay the onset of dementia and Alzheimer’s. Professor Masters says there tends to be an incubation period of about 10 years before the diseases set in. He says prevention needs to occur between 60 and 70. “It is at this stage that we need to deliver more specific diagnosis with targeted treatments to delay or prevent the diseases occurring,” he says.

Professor Masters recently won the 2007 Victoria Prize for his work into neurodegenerative disease research and the discovery of role of the protein PBL2 in dementia. The discovery revealed protein is expressed profusely in people with the disease. Professor Masters and colleagues are currently investigating ways to target the protein to slow down and prevent the neurodegenerative diseases from occurring.

After 20 years of research in the field, Professor Masters says it is an exciting time with some real possibilities of new methods of diagnosis and treatments. “We are taking a two armed attack to the problem,” he says. “Through the AIBL study we are trialling a highly sensitive PET scan and a blood test which detects the protein.” Professor Masters says this could provide a much needed cost effective early detection test.

The second approach involves the development of targeted PBL2 protein drugs which is currently in phase two of a safety trial being conducted by University of Melbourne spin-off biotechnology company Prana.

Professor Masters says the future looks bright for people with dementia with the targeted drug treatments expected in the next few years. “We are very positive about the results and expect that in the next few years we would move into phase three, larger human trials,” he says.

By 2020 it is hoped the combined early detection tests and targeted treatments will be able to delay the onset of dementia by five years, moving the medium age of onset from 80 to 85 years.

Professor Masters says this will have major socioeconomic effects on aged care infrastructure including nursing home services in Australia. According to preliminary analysis by Deloitte, prepared for Neurosciences Victoria, aged health expenditure in 2003 was $738m for Victoria, of which $620m was spent on aged care, with a total of 40 000 Victorians suffering dementia.

The report reveals that at the current rate of ageing, by the year 2020, there will be 70 000 people with dementia. It says if the onset of the disease can be delayed there will be increased workforce participation by over $150 million per year and a further $300 million less spent on aged care.

Professor Masters says people approaching 60 should consider staying in a productive capacity for as long as they feel they can contribute. “To work part-time and be active like getting out into the garden is a great combination,” he says. “It is important that you keep as fit as possible. This will ensure a much more active healthy life into your 80s.”

Professor Ames says quality of life will be improved for people with dementia in the future if the disease can be compressed into a shorter and later period of life. In his practice he sees patients dealing with the issues of ageing. “Most elderly do not fear death, they accept death is coming; they just don’t want to be dependent, in pain or lose their dignity as time goes by,” he says.

Meanwhile, well into his eighth decade, David Solomon continues with his passion for research. His latest project involves working with colleagues to find a way of using a non-toxic chemical to minimise water evaporation from dams [BH1]. Professor Solomon says his friends can’t believe that he continues to work when he doesn’t have to. “They retired – they counted the days until they could,” he says. “I feel sorry for people who did work that wasn’t interesting for them. “I’m lucky I can still contribute to projects. If not, if I was just ‘a passenger’, I wouldn’t be in there.”

Professor Solomon’s honours include an Order of Australia (AM) and election as a Fellow of the Royal Society, London, and the FAA (Australian Academy of Science) and the FTSE (Australian Academy of Technological Sciences and Engineering)