The government’s decision to pump an extra $200 million into dementia research recognises the potential of Australian researchers to build on previous research, and there are several opportunities for Australians to contribute to studies, writes Dr David Ames.
Dementia represents a major public health challenge for Australia and most of the world. Today about one in a hundred Australians of all ages is affected by dementia; and purely because of demographic changes, that figure is projected to be close to three in a hundred by mid- century.
Alzheimer’s disease – an insidious illness in which brain cells become dysfunctional and then die – is the commonest cause of dementia, but over 50 causes of dementia have been described. Vascular disease due to atherosclerosis, processes related to Parkinson’s disease and excessive consumption of alcohol are other common causes of cognitive decline in Australia.
For the better part of three decades, and despite limited funding and a relatively small population, Australian researchers have contributed disproportionately to the rapid growth in knowledge about dementia, its causes and what we may be able to do to help people and families affected by it. Any account of the contribution of Australians would include the following examples:
In 1985 Colin Masters working with his German colleague Konrad Bayreuther, described the exact structure of the 42 amino acid amyloid protein which builds up in the brains of people with Alzheimer’s disease and appears to trigger a cascade of processes which lead to cellular inflammation, dysfunction and death. This discovery has enabled research into the origins, function and metabolism of this protein and may one day lead to effective treatments to delay the onset of dementia due to Alzheimer’s disease.
In 1987 Tony Jorm, Scott Henderson and Ailsa Korten working at Canberra’s Social Psychiatry Research Institute integrated all published studies of dementia prevalence to show that, regardless of how it was attained, the prevalence of the disorder doubles every five years from ages 60 to 90. This important finding allowed subsequent accurate prediction of future rates of dementia in current populations, as virtually everyone who will get dementia over the next several decades has been born already.
In 1989 Henry Brodaty and Meredith Gresham working at the University of NSW published a paper which showed that educating and supporting spouse carers of people with dementia could modify the high levels of stress and distress such carers experience, and this and later work from these researchers showed that such education delays entry of people with dementia to residential care and is highly cost effective. This work led to the very effective ‘Living with Memory Loss’ education and support programmes run by Alzheimer’s Australia.
Nicola Lautenschlager and colleagues in Perth demonstrated in 2008 that 150 minutes of moderate exercise per day was associated with moderate benefits to cognition in people with mild to moderate memory complaints.
The AIBL study, initiated by CSIRO and involving over 1,000 volunteer participants and over 100 researchers from all over Australia, enabled research led by Chris Rowe and Victor Villemagne to describe in their seminal 2013 paper that the build-up of toxic amyloid protein in the brain extends over 30 years or more before the development of brain atrophy and memory impairment offering a long therapeutic window for potential preventative interventions.
The Australian Government’s recent initiative to pump an extra $40 million into dementia research annually for the next five years recognises the importance of dementia as a public health challenge and the potential of Australian researchers to build on previous research.
Contributing to future knowledge
A number of opportunities for Australians to contribute to the development of future research knowledge exist at present.
Regular physical activity has been shown to improve mental as well as physical health and to contribute to healthy ageing. National physical activity guidelines recommend that older adults should try to conduct at least 150 minutes of physical activity per week to be able to enjoy the health benefits associated with physical activity. More recently it has been shown that exercise can contribute to brain health by supporting memory and other cognitive functions. It is currently estimated that in approximately 20 per cent of cases the symptoms of Alzheimer’s disease, the most common cause of dementia, could be significantly delayed or even prevented if middle-aged and older adults were more physically active.
How physical activity exactly supports brain health in older people is the subject of intensive research across the globe.
Some of the underlying mechanisms identified so far include protecting the health of blood vessels in the body, strengthening the heart and therefore providing more oxygen to brain cells, as well as activating healthy brain metabolism directly. However, sedentary lifestyle is common and increasing when people age.
Changing behaviour is not easy and many older adults find it challenging to develop the confidence to get started. The National Ageing Research Institute (NARI), in collaboration with The University of Melbourne, is currently conducting the INDIGO research study. It is investigating whether setting personally meaningful exercise goals and receiving encouragement from a physically active volunteer mentor could be effective in helping to overcome a sedentary lifestyle. Participants take part in a six-month, home-based physical activity program. The time commitment for physical activity gradually increases to 150 minutes weekly. Participants follow individualised programs, and aim to reach personal fitness goals, which take into account medical history and personal preferences.
The study is inviting community members to join if they are: aged between 60 and 80 years; living in the community in the greater Melbourne area, do less than 60 minutes of leisure physical activity weekly and have noticed changes to their memory. If you are interested in being involved in this study or want more details, contact Ellen Gaffy at NARI on (03) 8387 2296.
NARI is conducting another study by providing a physical activity or social support intervention aimed at helping to alleviate the stress and burden of caring for someone at home.
The IMPACCT study is unique in that it not only involves the care-giver but also the person they are caring for, and all phases of the study are conducted at home and over the telephone. This vital study is also inviting community members to participate. If you are aged 55 years and over and live with and care for someone aged 60 years of over and you are interested in being involved in this study or want more details, contact Edwina McCarthy at NARI on (03) 8387 2315.
Professor David Ames is the executive director of NARI and the University of Melbourne Foundation Professor of Ageing.