US blood test detects alzheimer's with 95% accuracy

A new study in the US has revealed that a blood test can detect Alzheimer's disease in its early stages with high accuracy.

In research conducted by experts at the Mayo Clinic, two proteins found in blood plasma were examined for Alzheimer's diagnosis. These proteins—amyloid beta 42/40 and p-tau217—are linked to the buildup of amyloid plaques, one of the disease's key symptoms.

According to the study, the developed blood test showed 95% sensitivity in identifying individuals with memory problems, meaning the vast majority were accurately diagnosed, with very few missed. The test's specificity rate was 82%, indicating a high level of accuracy in ruling out individuals without dementia symptoms.

REAL-WORLD DATA STUDY

According to the World Health Organization, 57 million people worldwide were living with dementia in 2021. The new blood test has also been approved by the US Food and Drug Administration (FDA).

The study was conducted with more than 500 participants in a real-world clinic setting. Dr. Gregg Day, who led the study, noted that the test was as effective as current invasive methods:

"The blood test achieved 95% sensitivity and 82% specificity for Alzheimer's diagnosis. When applied in a clinic, this accuracy is as effective as cerebrospinal fluid biomarkers, but much more practical and cost-effective."

Researchers also observed significantly higher levels of p-tau217 in Alzheimer's patients.

Dr. Day emphasized that the next step should involve evaluating the test in larger, more diverse patient groups, including those with early-stage Alzheimer's who do not yet show cognitive symptoms.

EXPERTS: A POTENTIAL BREAKTHROUGH

Dr. Richard Oakley, the Research and Innovation Director at the Alzheimer's Society in the UK, found the results promising:

"This study shows that blood tests make Alzheimer's diagnosis faster, easier, and more accessible."

Oakley also highlighted that the test could help differentiate cognitive decline caused by other types of dementia.

"Blood tests will be crucial in speeding up the diagnosis process and allowing patients to access the treatment and support they need more quickly."

In the UK, the Alzheimer's Society, Alzheimer's Research UK, and the National Institute for Health and Care Research are supporting the multi-million-pound Blood Biomarker Challenge, aimed at integrating these blood tests into the National Health Service (NHS) by 2029.

MORE TESTING NEEDED IN DIVERSE PATIENT GROUPS

Dr. Julia Dudley, Director of Research at Alzheimer's Research UK, said:

"Improving diagnosis is an urgent need. This study shows that blood tests can accurately detect Alzheimer's disease in people with early-stage memory and thinking problems."

However, Dudley pointed out that the participants in the study may not fully represent the diversity of all dementia groups, and that the tests should be trialed more widely in real-world settings.

The Blood Biomarker Challenge in the UK is collecting blood samples from thousands of individuals to provide comprehensive data for this purpose.

"Such studies will contribute to making diagnosis easier and faster, helping us move one step closer to the ultimate goal of treatment."