Kiwi scientists believe it might be possible to catch the earliest signs of dementia - potentially even decades before diagnosis.

"Imagine you have been diagnosed with dementia," explained the University of Auckland's Associate Professor Maurice Curtis, who is leading a major three-year study just funded by the Health Research Council (HRC).

"You're told that it will progressively and irreversibly deprive you of your ability to think, your personality, and your independence.

"Now imagine your doctor tells you that you could have been treated if you were diagnosed 10 years earlier, but the damage to your brain now is too extensive.


"This is the problem we are trying to solve."

Dementia currently affects an estimated 60,000 Kiwis - a figure expected to almost triple by 2050 - and cost New Zealand's health system nearly $1 billion.

The driving force behind the study was a large New Zealand family whose members carried a genetic mutation known to cause frontotemporal dementia.

With 25 members of the family recruited into the study, it was the world's largest multi-generational study into this type of dementia.

By assessing blood tests taken annually and measuring ongoing changes in thinking and sense of smell, this longitudinal study aims to compare changes that occur between members of the family who carry the gene and those who don't.

"This will allow us to measure potential markers of dementia up to 30 years before expected clinical onset, which could then make early intervention possible," Curtis said.

"We are focusing on non-invasive, cost-effective diagnostic markers, in the hope that they could one day be used widely as a screening tool for pre-clinical dementia."

Also announced today is another study focused on the brain, and which seeks to reveal the fundamental mechanisms that disrupt brain "plasticity" and affect our ability to learn and remember things.

"The ability to form memories is fundamental to all mental abilities, and there are profound consequences when memory function is impaired, including Alzheimer's Disease, stroke and traumatic brain injury," said study leader Professor Wickliffe Abraham, of the University of Otago.

His team will be looking into the role of "astrocytes" – cells that support and help the function of nerve cells in the brain.

"In the past 10 to 15 years, astrocytes and how they work together with the nerve cells has become a real hot topic," Abraham said.

"Under normal conditions, they may be involved in protecting memories from interference, but in the presence of disease they may actually generate memory deficits."

His study is poised to make a significant contribution to the growing international field of astrocyte biology and our understanding of how memory mechanisms are regulated.

"Understanding these processes may help identify new targets for therapeutic interventions to rescue diseased memory and cognition."

Meanwhile, Otago University's Professor Julian Crane and his team have begun another three-year, $1.1m study looking at whether toxic moulds are a health hazard in New Zealand homes.

It built on previous research that had shown people who live in cold, damp homes – most of which are mouldy – had much higher rates of respiratory problems such as asthma, colds and influenza.

But what is not known is exactly why cold, damp mouldy homes give people more breathing problems, Crane said.

"We know that quite a lot of these leaky homes grow mould that produce mycotoxins, our question is do they cause the breathing problems?" he said.

"The question is, could it be that very small amounts of these mycotoxins are causing inflammatory problems in the airways which lead to coughs, wheezing and an increased risk of colds?"

The team would try to answer that by using chemical traces to measure the many microbes found in dust in homes around the country.

The HRC has invested more than $55m in 49 projects that make up the latest round of studies, which spanned from Pacific health to biomedical research.

"All of them delve into important health issues, and many pose questions that affect us all in some way," said HRC's director of Research Investments and Contracts, Dr Vernon Choy.

"They really do have the potential to improve the lives of all New Zealanders."