Significant research indicates that a straightforward blood test can identify early symptoms of Alzheimer’s Disease (AD) up to 15 years in advance, as reported by The Times of London.
Neuroscientists specializing in neurology from the University of Gothenburg in Sweden have developed a method to detect the presence of phosphorylated Tau 217 (pTau 217), a protein commonly associated with Alzheimer’s Disease, with remarkable efficacy.
The testing procedure, known as an assay, was devised by the company ALZpath. As outlined in a study published in the Journal of the American Medical Association, this assay provides a relatively painless and cost-effective alternative to spinal taps for assessing an individual’s susceptibility to the disease.
Blood Tests in Alzheimer’s Risk Assessment
The scientific community has been cognizant for several years of the potential of employing blood tests to measure tau or other biomarkers for the assessment of Alzheimer’s disease risk.
In the preceding year, the inaugural blood test for evaluating beta amyloid protein, named AD-Detect, became accessible for consumer acquisition in the United States.
It was designed to assist individuals with mild cognitive impairment in discerning their susceptibility to Alzheimer’s disease.
Some researchers have expressed reservations regarding the scientific underpinnings of the test. Quest Diagnostics, the company responsible for the test, has clarified that its purpose is not to diagnose Alzheimer’s but rather to evaluate an individual’s risk of developing the disease.
The test utilized in the recent study, known as the ALZpath pTau217 assay, is a commercially available tool developed by the company ALZpath, which contributed materials for the study without charge.
One of the research’s main authors, Nicholas Ashton, a professor of neurochemistry at the University of Gothenburg in Sweden, believes the technology will soon be available for clinical use, despite being limited to research applications.
Decisive Blood Test Results for 80% of Participants
The researchers discovered that when utilizing the p-tau217 immunoassay on a participant’s blood sample, the blood test demonstrated comparable results and precision in detecting abnormal beta amyloid and tau as those obtained from the participant’s spinal tap or brain scan.
Approximately 20% of the study participants received blood test results that, in a clinical context, would have necessitated further examination through imaging or a spinal tap due to ambiguity.
“This represents a notable reduction in the need for expensive and resource-intensive procedures,” Ashton conveyed in the email.
Consequently, based on the study’s findings, “we believe that a blood test and clinical evaluation can conclusively determine outcomes in 80% of individuals undergoing investigation for early signs of dementia.”
However, despite the high accuracy of the blood test in predicting the presence of crucial Alzheimer’s disease traits in the brain, it is not guaranteed that individuals with these characteristics will inevitably progress to developing the disease.
Moreover, the specificity of the p-tau test is confined to Alzheimer’s disease. Therefore, if an individual tests negative but exhibits signs of cognitive impairment, this test cannot ascertain alternative causes for their symptoms, such as vascular dementia or Lewy body dementia.