The test can reveal the risk of dementia up to 25 years before symptoms appear
A new blood test could determine a woman’s risk of dementia 25 years before symptoms appear.
That’s according to a new study from the University of California San Diego, which found that a certain protein biomarker associated with the early stages of Alzheimer’s disease was “strongly linked” to the risk of dementia in the future.
Researchers analyzed blood samples from 2,766 participants in the Women’s Health Initiative Memory Study in the late 1990s, according to the study report.
The women ranged in age from 65 to 79 years old and showed no signs of cognitive decline at the start of the study.
After following the participants for up to 25 years, the researchers concluded that the biomarker phosphorylated tau 217 (p-tau217) was “significantly associated” with mild cognitive impairment and dementia.
Women who had high levels of ep-tau217 at the start of the study had a “greater chance” of developing the disease. The findings were published today in JAMA Network Open.
“The key takeaway is that our study shows that it is possible to detect the risk of dementia two decades in advance using a simple blood test in older women,” first author Aladdin H. Shadyab, UC San Diego associate professor of public health and medicine, told Fox News Digital.
“Our findings show that the blood biomarker p-tau217 can help identify people at high risk of dementia long before symptoms start,” he added.
This longer lead time could open the door to earlier prevention strategies and more targeted monitoring, rather than waiting until memory problems are already affecting daily life, according to Shadyab.
“As research progresses, these biomarkers may help us identify who is most at risk and develop strategies to delay or prevent dementia,” he said.
This risky relationship was anything but, however. Women over 70 with high levels of ep-tau217 had “adverse cognitive outcomes” compared to those under 70, as did those with the APOE ε4 gene, a known risk factor for Alzheimer’s disease.
The study also found that ip-tau217 was a stronger predictor of dementia in women randomly assigned to receive estrogen and progestin hormone therapy compared to those who received a placebo.
“Blood-based biomarkers such as p-tau217 are particularly promising because they are less invasive and may be more accessible than brain scans or spinal fluid tests,” said senior author Linda K. McEvoy, a senior investigator at the Kaiser Permanente Washington Health Research Institute and a professor emeritus at the Herbert Wertheim School of Public Health, in a release.
“This is important to accelerate research into dementia risk factors and to test strategies that can reduce the risk.”
A blood test for Alzheimer’s disease is still being studied and is not recommended as a routine test for people without symptoms, Shadyab notes.
More research is needed before this approach can be considered for clinical use in pre-clinical studies.
Future research should investigate how other factors – such as genetics, hormone therapy and age-related medical conditions – may interact with plasma p-tau217, the researchers added.
“The study only examined older women, so the findings may not apply to men or younger people,” Shadyab noted. “We also examined all dementia outcomes rather than specific subtypes such as Alzheimer’s disease.”
