A game-changing new blood test for Alzheimer’s disease will soon be rolled out in Australia, but there’s a good reason why it won’t yet be for everyone.

Confirming a diagnosis of Alzheimer’s disease will soon be as simple as having a blood test, with a radical new method able to detect precursors decades in advance.

However, those behind it are cautious about who will be taking the test, saying if used irresponsibly it could create more uncertainty for patients. 

Further clinical trials will be done on the Therapeutic Goods Administration-approved test at the new Asia-Pacific Centre of Excellence for Alzheimer’s Disease Diagnosis, to be officially opened by Health Minister Mark Butler in Sydney on Thursday.

The centre is a collaboration between not-for-profit medical research institute Neuroscience Research Australia (NeuRA) and Swiss healthcare giant Roche. 

The test works by detecting the two proteins associated with Alzheimer’s disease – amyloid and tau – which begin to accumulate in the brain decades before a person develops symptoms.

Previously, the main diagnosis methods were either a lumbar puncture or an expensive type of brain scan that is not widely available.

For those in the early stages of Alzheimer’s disease, the simple and non-invasive new blood test offers an opportunity to plan for what’s ahead and, if they choose, commence preventative therapies.

‘Earlier is definitely better for people who have symptoms,’ Associate Professor Emma Devenney, a NeuRA neurologist, told AAP.

‘It’s really important for people to plan while they still can, to give them time to do the things that they want to do.’

If all goes well, the test will be available through specialist referral across Australia by the end of the year and could ultimately be accessed through Medicare.

While a major development, it would initially only be available to those already showing symptoms, according to Associate Professor Devenney, who will oversee the centre.

This is because while the test can detect the precursors to Alzheimer’s, it cannot yet give a time frame as to when, or even necessarily if, the disease will appear.

‘It doesn’t tell you that you have the disease; it tells you that you have the changes in your brain – the abnormal proteins – that are associated with the disease,’ Professor Devenney said.

A person who gets tested at the age of 60 and is positive, for example, may not experience symptoms until decades later, if at all.

‘So I think we have to be really responsible in how these tests are rolled out into the community at the moment,’ she said.

Ultimately, Associate Professor Devenney and her colleagues are hopeful that, with further developments, the test will be able to give physicians more certainty as to when symptoms will begin to appear.

‘At some point I anticipate that it will be like going to get your cholesterol checked,’ she said.

‘And hopefully by that stage we will have preventive treatments.’