Scientists have developed a new blood test that can accurately detect early signs of Alzheimer’s disease.
The test works by analyzing two proteins found in blood plasma: p-tau217 and amyloid beta 42/40, both of which are linked to Alzheimer’s.
According to the study, the new blood test has a sensitivity of 95 percent, meaning it correctly identifies 95 percent of individuals with memory issues. It also showed a specificity of 82 percent, making it highly reliable in ruling out those without dementia.
Led by Dr. Gregg Day, the study involved more than 500 participants at an outpatient memory clinic.
Since then, the blood test has received FDA approval in the United States.
Dr. Day noted that the blood test performed just as well as more invasive diagnostic methods.
In a clinical setting, the results were very similar to those obtained from cerebrospinal fluid biomarkers. However, it had the added benefit of being convenient and cost-effective.
Overall, researchers found that individuals with Alzheimer’s disease had higher levels of p-tau217 in their blood compared to those without dementia.
Dr. Gregg Day said that the next step is to evaluate the test in more diverse patient populations, including people in the early stages of Alzheimer’s who may not yet show cognitive symptoms.
Dr. Richard Oakley, associate director at the Alzheimer’s Society in the UK, also praised the new blood-based test, calling it “very accurate.” He believes it could be used alongside other diagnostic tools to improve early detection and diagnosis.
While the new blood test is mainly designed to detect Alzheimer’s disease, it may also help evaluate other forms of dementia. However, more research will be necessary.
Currently, diagnosing dementia can be costly, time-consuming, and often involves invasive procedures. The introduction of a blood-based test could transform access to care and treatment, making early detection more accessible and efficient.
Dr. Oakley called the U.S. approval of the test “great news” and expressed hope that similar progress will be made in the UK.
Its mission is to make blood-based testing for dementia widely available by 2029.
Dr. Julia Dudley, who leads Alzheimer’s Research UK, is hopeful that the new blood test would change the way dementia is diagnosed. However, she noted that the participants in the study may not fully represent the diversity of people living with dementia.
She emphasized the need for more studies to determine whether the blood-based tests will be accurate in a real-world setting.
