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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.
Must have forgot to post a comment.
I'm not sure I really want to know, given that there is nothing I can realistically do to avoid a rather grim fate.
Now I can know for sure if I'm going to get an incurable brain degenerative disease...
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.
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.
Can we require candidates for public office to take the test? Tim S
...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.
People at risk of Alzheimer's might want to chew nicotine gum or otherwise stimulate their nicotinic acetylcholine receptors. It may have some protective effects, but won't do anything about the beta amyloid tangles.
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.
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]
I thought FDA stood for Food and Drug Administration. This is a blood test which is neither.
Overfitting...
Elan's Bapineuzamab, affectionately known by some as Braino, is about to enter phase III testing for Alzheimers. If any of the rumors, in the industry, are true, it may be the first drug to effectively treat this terrible disease. It is a mono-clonal antibody which get the immune system to attack Beta Amyloid protein plaques, which are one of the theorized causes of Alzheimers.
"To those who are overly cautious, everything is impossible. "
we have a camp for those who test possitive.
Why such a fancy test? Drop them off downtown. If they come back it was meant to be.
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
Self termination.
Or more specifically, writing a living will (correct term?) to determine if you want to be resuscitated before your power of attorney has to make that decision for you.
Slashdot: Curing Alzheimers daily since 1997.
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This is a step in the right direction.
Understanding the scope of the problem is the first step on the path to true panic.
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.
I for one would not want to live with alzheimers. I actually wouldn't even consider that living. I can't read, watch TV or movies, surf the internet, make conversation... Is there anything I *can* do with alzheimers except veg out? That aint life. If I tested positive I would try to gauge just how long I had before my memory and overall thinking ability would diminish to the point that I could no longer self-terminate and do myself right before that time. I think I might choose to go like this. Either that or death by heat exhaustion in the desert. I don't like guns.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
...where's my keys?
Ok, so call me a humorless blob if you like, but I knew I was going to find jokes in here about Alzheimer's. My best bet would be that those who joke about it have never witnessed the havoc it wreaks on a person's mind. My grandfather died from Alzheimer's in 1994 when I was 14. Unfortunately, I never got to really "meet" him because by the time I was only enough to talk, he had begun progressing into the disease. By the time I was 8, he know longer knew my name. He seemed to look at me with some familiarity, but that was about it. Eventually, he would get so anxious (some of you may be aware of Sundown Syndrome) that he would leave the house and go for walks and get lost. We'd have to hunt him down in the middle of the night, worrying whether he'd been hit by a car. One time we found him walking the streets in the cold in nothing but his underwear.
It is a terrible, God-forsaken disease. The poor souls who suffer with it are trapped in their own minds and I personally believe they KNOW it but are unable to express it. As my grandfather progressed into the disease, he reached a point where he had trouble expressing anything coherently, but he would wrong around saying, "SOMETHING is wrong with me but I don't know what it is! Something is wrong with my mind!" It was terribly depressing and disheartening.
Think twice before you joke about this awful condition.
is to refuse coverage for anyone who tests positive for Alzheimer's disease.
The rush to bring this to market is purely from insurance companies, so they can "cherry-pick" only healthy clients and reduce their costs.
It seems increasingly common for us to be developing tests for things we cannot treat anyway. I wouldn't argue that we shouldn't develop such tests, however the significance of the test's development is debatable at best. I would agree that I don't want to know whether or not I have risks for something I couldn't do anything about anyway. That sounds like a way to increase people's stress levels worring about something that may or may not occur (or even will occur with certainty, but at an unknown time in the future). Some will argue it's better to know, however I'm almost certain the only outcome of having test results like this available is insurance companies having a reason to say you have a pre-existing condition and screw you for coverage and/or rates. If you never knew you were at higher risk, you'd still end up with the disease (or not) but won't have been bent over in the meantime. I know which way I'd go (mind you I'm the sort of person who never wants to be lying under a bus regretting I've been eating tofu for dinner for years when I'd rather have had steak). -- ~AC
I understand that the FDA is very cautious with drugs, but how cautious are they in the approval of blood tests (or urine tests for that matter)? I could see test reliability being an issue (considering that harmful drugs may be prescribed and mental anguish may be caused as a consequence of a false positive), but is there any reason for this to be any more dangerous than any other blood test?