Medical Discovery News - A simple test for Alzheimer’s
By Norbert Herzog and David Niesel
If you could take a test that would determine whether you would develop an incurable, degenerative and fatal illness, would you? Or would you rather not know, choosing to remain blissfully ignorant?
This is the dilemma that seniors may face because of a new test that claims to predict Alzheimer’s disease. A study of those age 70 or older claims to verify with 90 percent accuracy a test of whether they will develop the disease in the next two to three years. Currently, 35 million people worldwide have Alzheimer’s, a number that is predicted to rise to 115 million by 2050.
There is currently no single test that can establish that someone even has Alzheimer’s, let alone one that can predict who will develop it.
A complete physical, including questions about any symptoms of dementia such as confused thinking, trouble focusing or memory problems, is usually the first step in diagnosing Alzheimer’s.
A physician will also perform tests to rule out other possible disorders. Physicians can test reflexes, coordination, muscle tone and strength, eye movement and sight, coordination, speech and sensation.
A type of brain scan called positron emission tomography, or PET, detects the levels of plaque, one key indicator of Alzheimer’s, and new MRIs are being used to determine brain volumes to measure shrinkage, another hallmark of Alzheimer’s.
Tests like these are starting to be used but are limited because they are invasive, time-consuming, expensive or experimental.
There are also certain forms of genes that increase the risk of developing Alzheimer’s, for which there is a blood test, but that only identifies people at higher risk of developing Alzheimer’s, not whether a person will develop or has the disease. At this point, the only way to definitively prove the presence of Alzheimer’s is through an autopsy.
The new test is based on the levels of 10 different lipids (fats in the blood). If they are low, the subject is likely to develop Alzheimer’s. The lipids measured arise from the breakdown of neural cell membranes in the brain.
This appears to be the first test that can accurately detect Alzheimer’s before symptoms appear. If this test is approved, it would probably be included in the routine panel of tests run during an annual physical exam. Researchers said it could be available for use in clinical studies in as few as two years.
Current drugs used to treat Alzheimer’s have not been successful at slowing or reversing the disease. It has been suggested that these drugs may be more effective if they were administered earlier.
Since there is no test to identify Alzheimer’s until symptoms appear, there is no way to treat patients any sooner. If more studies can prove this new test is as good as it seems, it may open the door to earlier, more effective treatments with current drugs and the possibility of testing novel treatments to prevent or slow the onset of this debilitating disease.
Professors Norbert Herzog and David Niesel are biomedical scientists at the University of Texas Medical Branch. Learn more at medicaldiscoverynews.com.