Until recently there hasn't been a test for Alzheimer's disease. As you probably know, Alzheimer's is a degenerative brain disease, the physical manifestation of which is abnormal protein plaques and tangles in the brain.
Typically people with signs of dementia can't be definitively diagnosed with Alzheimer's until after they're dead, when an autopsy determines whether the tell tale protein plaques and tangles were present.
So it sounds like good news that in April the FDA approved a new type of PET brain scan capable of spotting the plaques in the brains of living people, using a special radioactive tracer called Amyvid.
The test holds promise, since it could find brain plaques years before serious dementia symptoms develop, giving people the precious ability to get their affairs in order and make their wishes known while still mentally sound.
But, the test is not a guaranteed predictor of Alzheimer's because, confusingly, some people with Alzheimer's symptoms turn out, upon autopsy, to not have abnormal brain plaques, while other people who appeared to be in good neurological condition when living are discovered, once deceased, to have physical markers of Alzheimer's in their brains.
This article in the Philadelphia Inquirer gives more details on the new test for Alzheimer's and the dilemmas it poses.
If you could take the test would you—knowing that there's no cure or great treatment for Alzheimer's, and that even if the test finds amyloid plaques you might not go on to develop the disease? When my memory fails me I occasionally worry that I have early onset Alzheimer's . . . but rather than looking for plaques on my brain I'd rather stay blissfully ignorant, and ease my worries with a brain-healthy glass of wine.
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