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Promising Blood Test for Alzheimer's
The online edition of the British journal Nature Medicine has a study of a blood test for Alzheimer's disease, developed at Stanford. The test lights up if 18 specific molecules are present in a blood sample. Using samples of stored blood, the test proved 90% accurate in identifying people who had been diagnosed with the disease by other methods. It was also 87% accurate in distinguishing samples from people who do not have Alzheimer's but exhibit some other form of dementia. The numbers of samples involved were small — SFGate's writeup has some details. The Mercury News's article says the test's developers want to begin selling it to laboratories in 2008, for which FDA approval would not be required. They hope to get FDA approval for general use by 2009.
I'm not sure I really want to know, given that there is nothing I can realistically do to avoid a rather grim fate.
Is Alzheimer's an unavoidable disease? I don't have any actual papers in front of me, but I thought I heard that frequent use of the mind and critical thinking were a great way to keep your brain "in shape." Maybe knowing that you have Alzheimer's disease will give you the chance to live a normal life with the occasional crossword, sudoko, critical reading, etc.
Either way, I'd want to know.
Life is rarely fair. Cherish the moments when there is a right answer.
I would (not very educatedly) guess that the benefit of such a test is not in verifying that a patient has Alzheimer's but rather they don't. By ruling out Alzheimer's, doctors can focus on other, possibly curable, mental diseases. It would be terrible if someone degenerates into a condition common to a person suffering Alzheimer's, when really they have something different altogether that can be treated (medicine, surgery, etc). But what do I know, I'm no brain-surgeon!
Who cares about this, all it can do is tell you you might have a disease that we can't cure. At most it would just make the person more depressed into thinking he/she actualy has the disease.
One of the most important benefits of this research is that they've managed to identify some biological changes that occur before clinical symptoms. That means they can start to identify the processes leading to the disease, which might lead to treatments. If this is real then it's a huge step in understanding Alzheimer's disease.
You're right though in a way, there's not a lot you can medically do (at the moment) if you know you're going to get AD in the near future, but it might help you to prepare you or your family in other ways.
Can we require candidates for public office to take the test?
More to the point - can your medical insurer make you take it.
My grandmother's suffering from Alzheimer's, and the OP gave me a chuckle nonetheless. Nobody's forcing you to laugh, but some of us find humor useful in dealing with hardship.
That's funny, but how is it a pun?
TFA does quote the false positive rate
That quote doesn't describe the false positive rate. It describes the number of cases of non-Alzheimer's dementia that their test correctly doesn't call Alzheimer's. The false positive rate would indicate the number of participants without Alzheimer's (including this group of 39) who incorrectly test as having Alzheimers.
Also, remember that their test is also designed to detect people at risk of developing AD years in the future, so, as is also pointed out in the article false positive rates can not be fully determined for some years.
True, but that would seem to make the test worthless. It doesn't always catch people known to have it, it at least sometimes (5 times out of 39) flags people known to not have it, and for the rest we can't say if it works or not.
When I call that an abuse of statistics, I very much mean it. Give me 120 protein markers in a small enough group (in this case, fewer subjects than proteins under consideration!), and I'll get you a similar level of accuracy in predicting whether they wear boxers or briefs.
It may turn out that they have something. But as written, I'd take this study with a whole salt-lick.