An Australian research project has found a way to bring forward the detection of early stage Alzheimer's disease by up to 18 months.

The leader of the team that made the discovery, Professor Christopher Rowe of the Austin Hospital in Melbourne, says early diagnosis and treatment presents medical practitioners with the best opportunity to delay the onset of Alzheimer's.

"While the discovery is at an experimental stage, this work places Australia at the forefront of neuro-imaging in Alzheimer's disease," Professor Rowe says.

A 2004 Access Economics report calculated that if the average age of onset of Alzheimer's was raised by just five months, cumulative savings of A$1.3 billion would be realised by 2020 rising to A$6.6 billion by 2040.

Alzheimer's disease is characterised by very high levels of a molecule called beta-amyloid in the brain. The project has demonstrated that a neuro-imaging scan called PiB PET can be used to identify individuals who will develop Alzheimer's disease up to 18 months earlier than all currently available diagnostics.

PiB PET can show the beta-amyloid in the brain which potentially allows clinicians to distinguish patients with early Alzheimer's disease from others without the disease, even before clear signs of memory loss are present.

The research was undertaken as part of the Australian Imaging, Biomarkers and Lifestyle (AIBL) Flagship Study of Ageing.

The AIBL Flagship Study of Ageing is a collaboration initiated by the CSIRO Preventative Health National Research Flagship. AIBL is a joint activity between the University of Melbourne, Edith Cowan University - Western Australia, Neurosciences Australia, Mental Health Research Institute of Victoria and National Ageing Research Institute, and the Preventative Health Flagship.

The leader of the AIBL study, Professor David Ames, says the study has the potential to markedly reduce the burden this disabling illness places on both individuals and society.

"Early presymptomatic diagnosis is an essential development which will allow us to test new disease modifying therapies with the aim of delaying the onset of Alzheimer's disease in susceptible individuals," Professor Ames says.

The Director of CSIRO's Preventative Health National Research Flagship, Dr Richard Head, says the result highlights the value of a national collaborative team working together on one of Australia's biggest challenges.

Alzheimer's Australia has worked closely with AIBL to attract and co-ordinate the many volunteers who have made this study possible.

"Alzheimer's Australia is pleased to be part of this very exciting research and we look forward to its continuation," Alzheimer's Australia National Executive Director, Glenn Rees, says.

The findings were presented at international meetings in the USA on June 16 and will be presented in July at the International Conference on Alzheimer's disease in Chicago.