Protein-specific blood test may revolutionise diagnosis for Alzheimer’s disease
New research led by fellows at Lund University in Sweden, by way of an inexpensive blood test, could be accurate indicator of both plaques and tangles characteristic of Alzheimer’s disease (AD) in living patients. So far, the diagnosis of AD has been based on assessments of the brain (neuropathological) after a patient has died, but the phospho-tau217 (p-tau217) blood test may be able to differentiate between persons with and without AD and detect the disease as early as 20 years before the onset of cognitive impairment.
Researchers evaluated a p-tau217 blood test in about 1,400 cognitively impaired and unimpaired research participants from across Arizona, Sweden, and Colombia, coordinated from Lund University.The results varied for each cohort: the plasma p-tau217 assay discriminated between Arizona donors with and without the subsequent neuropathological diagnosis of “intermediate or high likelihood AD” with 89% accuracy, while higher p-tau217 measurements were correlated with higher brain tangle counts only among those who also had amyloid plaques; the assay discriminated between persons with the clinical diagnoses of AD and other neurodegenerative diseases with 96% accuracy in the Swedish cohort; and distinguished between mutation carriers and non-carriers 20 years before their estimated age at the onset of mild cognitive impairment in the Columbia cohort.
Equally important was how p-tau217, which is a major component of AD-related tau tangles, performed better in the analyses and in several other studied blood tests than p-tau181, another component of tau tangles.However, a revised p-tau181 blood test was just recently found to have promise in the diagnosis of AD.
“The p-tau217 blood test has great promise in the diagnosis, early detection, and study of Alzheimer’s,” said Dr. Oskar Hansson, Professor of Clinical Memory Research at Lund University. “While more work is needed to optimise the assay and test it in other people before it becomes available in the clinic, the blood test might become especially useful to improve the recognition, diagnosis, and care of people in the primary care setting.”
