Blood test may show Alzheimer's risk years in advance

A new study showed that certain proteins in the blood could indicate Alzheimer's risk years before symptoms begin. Experts say the test is not yet...

Scraper SystemJune 02, 2026, 07:12 PM

A simple blood test may help identify individuals at higher risk for Alzheimer's disease years before symptoms appear. However, experts say this method is not yet a standalone diagnostic tool or suitable for general screening. Researchers at the University of California San Francisco (UCSF) found that certain Alzheimer's-related proteins in the blood were associated with subtle differences in thinking and memory skills in middle-aged adults without dementia. The research team notes this is the first time such blood markers have been shown alongside mild cognitive differences in this age group. Kristine Yaffe, the senior author of the study, said that for some people who learn they carry these biomarkers, these tests could offer an opportunity to start interventions that might delay the onset of Alzheimer's. According to experts, early detection of risk could open an important door for preventive measures to be applied later. The researchers examined blood samples from 1,350 adults aged 53 to 69. The study looked at amyloid and tau proteins, which are distinctive features of Alzheimer's. Six percent of participants were found to have high levels of both proteins. Although this group did not have dementia, they showed slower response times to traffic lights and conversations. The same individuals also had more difficulty with tasks such as planning, organizing, and maintaining activities. In retesting five years later, those with high levels of Alzheimer's-related proteins were more likely to show faster declines in verbal memory and information processing speed. Scientists say these results strengthen expectations that blood tests could help doctors detect Alzheimer's risk earlier and more easily compared to current methods. However, doctors emphasize that while the study is valuable for research, the tests are not yet suitable for screening purposes. Professor Tara Spires-Jones of the University of Edinburgh, specializing in neurodegeneration, cautioned that such tests could be misunderstood, noting that the presence of proteins in the blood does not directly mean an Alzheimer's diagnosis. Spires-Jones stated that these findings only provide a clue about what is happening in the brain but represent a small part of the overall picture. According to her, this method cannot be considered a diagnostic tool on its own. These tests are currently approved in the US only for people who have symptoms. Also, these tests are designed solely to detect Alzheimer's disease and do not indicate other types of dementia. Researchers say that because some dementia risk factors are modifiable, early detection becomes even more important. Physical inactivity, smoking, depression, poor heart health, and low cognitive activity are among these factors. According to Yaffe, addressing modifiable risks could delay or prevent up to 40% of dementia cases. According to World Health Organization data, 57 million people worldwide were living with dementia in 2021, with about 10 million new cases emerging each year.

Blood test may show Alzheimer's risk years in advance

A new study showed that certain proteins in the blood could indicate Alzheimer's risk years before symptoms begin. Experts say the test is not yet...