Key Summary
- A study of over 2,700 women found that high levels of the p-tau217 protein can predict dementia risk up to 25 years before cognitive decline begins.
- The predictive power of the test was even stronger in women carrying the APOE-e4 genetic variant, a known risk factor for Alzheimer’s.
- British researchers have welcomed the study as it would lead to developing early Alzheimer’s detection blood tests.
Scientists have identified a blood protein that can potentially identify dementia risk in women, nearly two decades before the first signs of memory loss.
The study, published in JAMA Network Open, found that higher levels of p-tau217 as a "strong predictor" for dementia risk.
The researchers analysed data from the Women’s Health Initiative Memory Study and followed 2,766 women, aged 65 to 79 at enrollment in the late 1990s, for over 25 years. None of the participants had cognitive impairments at the start of the study.
The protein, p-tau217, which has been linked to the brain changes seen in Alzheimer’s disease, could predict a woman’s chances of developing dementia up to 25 years before symptoms develop, scientists have claimed.
Researchers from the University of California San Diego also said the protein is “strongly associated with dementia risk in men as well”.
The link was even stronger among those who had a higher genetic risk of Alzheimer’s, because they possess a genetic variant known as APOE-e4.
However, blood tests are not currently recommended for people who are not yet showing any signs of cognitive impairment.
The lead author of the study, Aladdin Shadyab, a professor of medicine at UC San Diego’s school of public health and longevity, said this kind of ‘long lead time’ would help doctors start early prevention strategies and more targeted monitoring.
The study also looked at how race, age and the use of hormone replacement therapy (HRT) can affect how effective the blood test is at predicting dementia risk.
British researchers have welcomed the study as it would lead to developing early Alzheimer’s detection blood tests.
Michelle Dyson, chief executive officer at the Alzheimer’s Society in the UK, said the studies were promising, but more research is needed.
