New research from the University of Otago – Ōtākou Whakaihu Waka has uncovered another clue to potentially identifying Alzheimer's disease early.
Using data from the Dunedin Multidisciplinary Health and Development Study's age 45 assessments, researchers investigated a specific biomarker in blood plasma, ptau181, which has been shown in other studies to be strongly associated with Alzheimer's disease in later life.
The biomarker was elevated in Study members who raised concerns about their cognitive health, such as their memory and thinking.
However, when tests were conducted, there were no detectable changes in brain structure.
Dr Ashleigh Barrett-Young
Lead author Dr Ashleigh Barrett-Young, of the Department of Psychology, says while further research is needed, the findings add to the growing evidence that Alzheimer's-related processes may begin decades before clinical symptoms appear.
"This means there may be an important window for prevention, which remains one of the most promising approaches for Alzheimer's disease," she says.
As part of the Dunedin Study's age 45 assessment, Study members reported any concerns about their memory and completed detailed cognitive tests before their brain structure and biological age were measured using MRI and DunedinPACE tools, respectively.
Dr Barrett-Young says the results show that subtle changes in cognition may occur before they reach measurable levels.
"This highlights the need for careful research to understand how early changes relate to later outcomes."
Tests to identify blood-based biomarkers are not yet available for routine use in Aotearoa New Zealand but have the potential to be accessible and widely available.
However, the discovery is another piece of the puzzle when it comes to identifying Alzheimer's early.
"Understanding the earliest stages of disease development is essential for designing effective prevention and treatment strategies, even if clinical tools are still some way off," Dr Barrett-Young says.
"Importantly, biomarkers like pTau181 reflect risk, not certainty."
Professor Moana Theodore
Dunedin Study Director Professor Moana Theodore says Dr Barrett-Young's leadership on the project highlights the global impact of research being carried out by New Zealand scientists.
"Following the recently completed and highly successful age 52 assessment, we are entering the next stage of the research with momentum," she says.
"The University of Otago Dunedin Study continues to inform global aging policy by demonstrating aging as a lifelong process allowing for better targeting of preventative healthcare."
Professor Theodore says the Study members are incredibly generous with their time and information.
"They take part to support future generations, knowing that this biomarker is still at an early, research-only stage and that individual results are not shared because scientists do not yet understand the long-term outcomes.
"Many have seen first-hand the multiple ways dementia can affect families and hope that the information that they provide will be used to reduce disease and help others."
