Testing a person’s blood for the presence of a type of protein called phosphorylated tau, or p-tau, may be a way to screen for Alzheimer’s disease with “high accuracy,” even before symptoms begin to appear, suggests a new study.
The study involved blood tests for a key biomarker of Alzheimer’s disease called p-tau217, which increases as other harmful proteins – beta-amyloid and tau – accumulate in the brains of people with the disease. Currently, to identify the buildup of beta-amyloid and tau in the brain, patients undergo a brain scan or lumbar puncture, which can often be inaccessible and costly.
But scientists found that this simple blood test has up to 96% accuracy in identifying elevated levels of beta-amyloid and up to 97% accuracy in identifying tau, according to the study published Monday (22) in the journal JAMA Neurology.
The test used in the new study, called the ALZpath pTau217 assay, is a tool developed by the company ALZpath, which provided materials for the study free of charge. The test is currently available only for research use, but Ashton said it should be available for clinical use soon.
ALZpath estimates that the price of the test may range from $200 to $500.
What’s most interesting is that a blood test for Alzheimer’s, like the one described in the new study, could be used to help diagnose both a person with early memory loss and a person long before they show any signs or symptoms of the disease, because changes in the brain can begin to occur about 20 years before the onset of obvious symptoms.
Early diagnosis will help specialists develop better treatments and ensure a better quality of life for patients.
Source: CNN