A simple blood test reveals a great deal about our health. Anemia, blood cancers, and infection can be detected in addition to learning information regarding heart, liver, and kidney function. And soon we may have a blood test for Alzheimer’s disease, as well.
Alzheimer’s disease’ isn’t typically suspected until symptoms begin interfering with daily living. More than 6 million Americans are living with Alzheimer’s disease, and countless others unknowingly have it as the disease develops in the brain 10-20 years before symptoms appear. By the time Alzheimer’s is evident, valuable time has been lost—time that could have been used to maximize experiences with family and friends, plan for the future, make end-of-life decisions, and take advantage of medical options available in early stages.
As of this posting, an Alzheimer’s disease diagnosis is made through a combination of basic screening and physical, emotional, and cognitive exams. There may be genetic testing if it’s believed to have run in a family. A more definitive diagnosis can be made with a spinal tap that detects tau proteins in cerebrospinal fluid. However, this is quite an invasive test and not covered by insurance.
The progression of Alzheimer’s disease begins when brain protein called amyloid beta accumulates into plaques. Another protein, tau, then produces tangles. Neurons begin to die from this build-up of plaques and tangles. Finally, brain tissue atrophies which can be seen as decreased brain volume on MRI testing.
PET brain scans are our best testing option at this time. However, the test requires an injection of a radioactive tracer for imaging, is expensive, and not covered by insurance.
All of these tests have limitations. Even PET brain scans and cerebrospinal taps do not provide information on changes in the neurons. Most importantly, our current tests are not able to detect Alzheimer’s until the disease has progressed significantly.
An exciting option on the horizon is a blood test that can be taken earlier in the disease process, perhaps even before symptoms begin. The Lumipulse G β-amyloid Ratio (1-42/1-40) is in the development stage and is hoped to be available soon.
We also have a new form of MRI that detects the loss of neurons that precedes brain shrinkage and cognitive decline. This test will then offer results sooner than the traditional MRI.
Current Alzheimer’s research focuses predominately on finding treatment for symptom management. Detection before massive destruction of cells would be more beneficial, and perhaps it would lead to a cure, which is not yet available.