A new blood test for Alzheimer's disease is 96% accurate at identifying the disease and can perhaps detect it even before symptoms such as memory loss (dementia) develop. An estimated 5.4 million Americans have Alzheimer's disease, the most common form of dementia, according to the Alzheimer's Association.
Currently, the only definitive way to diagnose the disease is by direct examination of brain tissue after the patient dies. Doctors use brain imaging, evaluation of behavior, psychiatric tests, and other means to diagnose the disease in the living, but none are highly accurate, and some are costly and not practical.
Robert Nagele, PhD, a professor of medicine at the University of Medicine and Dentistry of New Jersey School of Osteopathic Medicine and developer of the test explains:
''This is a simple test that has high accuracy and can be run from a single drop of blood. Brain cells die and when they die, they pop; they explode, like a water balloon breaking. Your body makes antibodies against the cell debris. We believe that happens so it can facilitate the cleanup of the cell debris. Many of these are related to the presence of the disease."
Nagele's team looked at blood samples from 50 people with Alzheimer's disease and 40 without. They also looked at blood samples from 30 breast cancer patients and 29 with Parkinson's disease; to be sure the test could be specific for Alzheimer's.
Overall, the tests identified 96% of those with Alzheimer's correctly. It correctly identified 92.5% of those who didn't have Alzheimer's. Nagele was able to form a list of antibody biomarkers needed to detect Alzheimer's disease to 10.
Snyder, PhD, a spokesperson for the Alzheimer's Association continues:
"Many labs are looking at this. They are all in the very preliminary, very early stages. We all know we need an accurate, relatively noninvasive way to diagnose Alzheimer's. What we have seen, at least in cerebral spinal fluid [tests], is that it hasn't held up across different labs. Patients can plan for their financial future, as well as their care. They can participate in clinical trials. When we do have therapeutic options available, the ultimate goal would be intervention."
Nagle is hopeful the test could be available within a year. Costs are difficult to estimate, but it could be about $200, which is quite affordable related to current test pricing standards.
More than 5.4 million Americans and 35 million people worldwide have Alzheimer's, the most common form of dementia. It has no cure and drugs only temporarily ease symptoms. Finding it early allows patients and their families to prepare, and ruling it out could lead to diagnosing a more treatable cause of symptoms, such as sleep problems.
Genetic testing is also at the innovation forefront in combating the debilitating disease. Scientists don't yet fully understand what causes Alzheimer's disease, but the more they learn about this devastating disease, the more they realize that genes play an important role in its development.
Some diseases are caused by a genetic mutation, or permanent change in one or more specific genes. If a person inherits from a parent a genetic mutation that causes a certain disease, then he or she will have a much higher risk of developing the disease. Sickle cell anemia, cystic fibrosis, and early-onset familial Alzheimer's disease are examples of inherited genetic disorders.
Written by Sy Kraft