Health news

New blood test method may predict Alzheimer’s disease

Diagnostic value of plasma phosphorylated tau181 in Alzheimer’s disease and frontotemporal lobar degeneration. New Delhi, 12th March 2020. Alzheimer’s disease is an age-related brain disorder that develops over many years. Toxic changes in the brain slowly destroy memory and thinking skills. Alzheimer’s Symptoms most often first appear when people are in their mid-60s. The disorder gets worse over time and eventually leads to severe loss of mental function. What is beta-amyloid and tau The process that destroys the brain involves two proteins called beta-amyloid and tau. Beta-amyloid clumps into plaques, which slowly build up between brain cells. Abnormal tau accumulates inside brain cells, forming tangles. Researchers have found that PET scans of the brain and lab tests of spinal fluid can reveal disease-related changes, or pathology, twenty years before the onset of symptoms. Although the disorder is not reversable, early treatment may help preserve daily functioning for some time. Early diagnosis of Alzheimer would also enable testing of novel drugs and other treatment approaches. However, PET imaging is expensive and involves radioactive agents, and spinal fluid tests are invasive, complex, and time-consuming. Researchers are looking for simpler, more cost-effective tests. A team led by Dr. Adam Boxer at the University of California, San Francisco investigated whether a new blood testing technique called Simoa could be used to measure the concentrations of tau and predict development of Alzheimer’s disease. The study was funded in part by NIH’s National Institute on Aging (NIA) affiliated to U.S. Department of Health and Human Services (USA), National Institute of Neurological Disorders and Stroke (NINDS), and National Center for Advancing Translational Sciences (NCATS). Results were published online on March 2, 2020, in Nature Medicine. The team collected blood samples from more than 400 people. They measured the concentration of ptau181—a modified version of tau that’s been linked with Alzheimer’s disease—in blood plasma, the liquid part of blood. Their analysis showed that the ptau181 in plasma differed between healthy participants and those with Alzheimer’s pathology confirmed in autopsies. The test could also differentiate Alzheimer’s pathology from a group of rare neurodegenerative diseases known collectively as frontotemporal lobar degeneration. The…