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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.
What the article fails to point out is the real benefit to getting early diagnosis for Alzheimer's. If people could be diagnosed earlier, they could get better care and avoid accidents.
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.
Would the pun "You have alzheimers but you just don't know it yet!" be considered poor taste in this context?
Monstar L
I always ask my dad "Do you remember the last time you were tested for Alzheimer's?"
It pisses him off...
Good security is based upon reality and common sense. Common sense is a function of having common knowledge.
...about Alzheimers is all the new interesting stories on /. every time I refresh.
(sadly, the same cannot be said about the goatse comments)
It is dangerous to be right when the government is wrong.
If I remember correctly, Alzheimer's disease is caused by the build up of obstructive plaques. these plaques specifically of the beta-amyloid variety are more than likely not dependant on how many crosswords you did or any critical reading you did. Genetics seems to play a very large role in whether you eventually get Alzheimer's disease although other factors could also increase the likihood of Alzheimer's disease. ie the genes associated with it may very well only be part of the story, perhaps in addition to having these genes, you also need certain environmental conditions- like brain damage, high blood pressure etc... Wikipedia goes into basic detail on the matter.
Sigs are too short to say anything truly profound so read the above post instead.
Interesting question. Should we require elected politicians to meet certain levels of health, and mental capacity? I think that might be a good thing, but it could set a dangerous president for the rest of society. I certainly wouldn't want to be denied a job due to my Alzheimer's, heart disease, or cancer risk factors.
Well.. maybe. Or Maybe not. But Definitely not sort of.
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.
Its not untreatable, and there are a lot of promising new therapies coming online.
However, right here and now, if you know you are going to get the disease in the future, you can:
And cholinesterase blocker drugs will improve cognition in the face of a falling neuron count - improving function although not modifying the disease itself.
Whilst there are many ethical questions to screening tests for diseases you cannot treat, alzheimers does not fit into that category. We all die of something. Its all about getting the most quality time on the planet. Having a test for this would be a good thing.
Please also note that there are already tests that can identify risk of alzheimers, such as for the ApoE epsilon 4 genotype, so the concept of a screening test that helps separate types of demetia already exists.
For a concise reference, see Wikipedia
Michael
There is no cryptographic solution to the problem where the intended receiver and the attacker are the same entity.
Can we require candidates for public office to take the test?
More to the point - can your medical insurer make you take it.
OK, there have been other tests (including one involving spinal fluid, ouch) that have been 90+% accurate (or were initially purported to be in manufacturer-sponsored studies).
It doesn't matter.
Dementia has lots of possible causes, and there's really no way to tell most of them apart from just seeing the symptoms. That means that a dementia screening is required, and when done by an appropriate specialist (usually a neurologist, neuropsychiatrist, or geriatric psychiatrist), it's roughly 90% accurate, PLUS you have either ruled out or discovered other more easily identifiable and sometimes reversible causes of dementia, which is important for what should be obvious reasons. That is why none of these tests have replaced the standard screening, although the companies that have produced them have spent millions trying to market them as suitable replacements. The accepted diagnostic standards haven't changed much in 20 years, really, the link given is still the gold standard or still a large part of the basis for more current standards for specialists or generalists.
The only big revolution is that some progress is being made on the metabolic processes that cause the plaques and tangles to appear in the brain, which might allow for preventative treatment, but it would probably need to begin in your 20's. Elan Pharmaceuticals was working on an antibody that could clear plaques from the brain, but it was unclear how much this would help those who were already suffering from AD, as brain cells will eventually start dying, although if this approach proves successful the disease may certainly be stopped and the damage kept from progressing, but it can't reverse existing damage.
And yes, this is my field. Here's some recommended reading for those looking for more info.
[command INSERTWITTYQUIP failed: insufficient wit]
Don't worry, we already have one of these in office in the US.
How about being denied a job for which the given ailment would prevent you from doing the job? That would be the point of having mental-related standards for people in office, so that they could do their job (and not the one of pandering to the lobbyists).
However, the FDA does not regulate: Advertsising, Alcohol (woot), Consumer Products, Heatlh Insurance, Drugs of Abuse, Meat and Poultry (USDA), Pesticides, Restaurants, and Water
I term this reverse confirmation bias: if many people have tried and failed, it must be impossible.
... until it wasn't.
But what credit is there to that? Many were the claims to transmute lead into gold. What proved impossible by chemical means was by no means impossible within the framework of the right technology. I think you need to study the "Four Colour Corollary". This theorem states that the truth or falsity of the theorem is entirely independent of the number of bozos who publish unfounded and incorrect speculations disguised as purported proofs. Furthermore, we still don't have a proof that could possibly have been discovered before the computer era, so the deck was stacked towards impossible
The same thing happened within the field of AI. This still annoys me. A lot of grand claims were put forward in the 1960s, and it all fell far short of what was promised. Nevertheless, there has been an unbroken stream of solid and important results, if not yet worth writing home about. Weren't the smart people silently expecting it to play out this way all along?
I feel the statistical results are the most important:
http://www.ucl.ac.uk/media/library/robotillusions
And there recent is progress even in the long discredited field of automatic proof:
http://www.maa.org/devlin/devlin_01_05.html
Guess what? Computers are now checking computerized proofs. Does this series converge, or not?
As for this new blood test, the human genome was sequenced a scant seven years ago, the explosive shock wave of proteomics is expanding almost at the limiting wave velocity, and we are now beginning to disentagle some of the fundamental neurochemistry involved. If there are any correlates in the blood whatsoever, it would be shocking to not find them at the present time, or in very short order.
Concerning percentage prediction rates, have we learned nothing? If you have a population of size N which you wish to classify into two distinct groups, given prior p and (1-p), the information required to achieve this is N * H(p), using Shannon's information measure. If this test provides any additional information beyond the prior, one can formally determine the ratio of the unknown information this test provides. If the test is worthless, the ratio will be zero. If the test is perfect, the ratio will be one. If the ratio comes out negative, you just assume the water goes the other direction (by metaphor with electrochemistry), and substitute the absolute value.
The interesting term is the cross entropy between what the experts can determine and what this test can determine. If the cross entropy is 100%, then either test gets you to exactly the same place, and it will probable come down to a matter of economics, which the cheaper approach prevailing. If the cross entropy is significantly less than 100%, then one will likely employ both tests, possibly using the cheaper test to screen the more expensive test, depending on tolerance rates for false negatives and false positives.
Given that they have included 18 elements in this test given a small positive sample size (they don't state their negative sample size), it's almost certain that some of these 18 factors are bogus, and will be eliminated as the sample size increases. If this test is bogus, the factors remaining will dwindle to zero, as the predictive rate also dwindles to nothingness. If the test is fundamentally predictive (to some ratio of the information content) as the bogus factors are pared out, the predictive ratio will likely improve by some marginal amount, maybe enough to be worth doing, maybe not.
In the 1970s one could make easy sport of predicting that any given claimant of the "four colour proof" was wrong and pat yourself on the back for an unbroken chain of confirmations. Great work: you've managed to predict that the world is full of de
Supposedly, it stops the damage and some functionality is restored. This is all based on rumor, as the results are being closely held at this time. The fact that phase III trials are being started prior to the end of phase II is very encouraging. It has also been designated as a "pivotal" trail by the FDA.
Disclaimer: I am an investor in Elan.
"To those who are overly cautious, everything is impossible. "
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.
An old man goes to the doctor. The doctor says, "I have bad news and Really Bad News. The bad news is you have Alzheimer's. The Really Bad News is that you have cancer and will die horribly within the month." The old man thinks for a minute and says, "Well, at least I don't have Alzheimer's!"
I cried real tears when Li Mu Bai died.
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.