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Biotech Science

Promising Blood Test for Alzheimer's 91

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.
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Promising Blood Test for Alzheimer's

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  • 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.
    Let me guess. It's also successful at diagnosing 88% of people who have no symptoms whatsoever?
    • by antifoidulus ( 807088 ) on Sunday October 14, 2007 @05:21PM (#20976449) Homepage Journal
      Would the pun "You have alzheimers but you just don't know it yet!" be considered poor taste in this context?
      • Re: (Score:3, Funny)

        by Descalzo ( 898339 )
        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!"
      • Re: (Score:3, Insightful)

        by Myopic ( 18616 )
        That's funny, but how is it a pun?
    • by pla ( 258480 )
      Let me guess. It's also successful at diagnosing 88% of people who have no symptoms whatsoever?

      From your low moderation score, I'd guess that most people didn't "get" the half-seriousness of your joke, but kudos for at least trying to keep people honest in reporting (or in this case, reading) statistics.

      But yeah, I too found it suspicious that they only quoted positive accuracies, completely ignoring false positives. It also doesn't say whether those numbers come from the same samples as used to pick
      • Um... TFA does quote the false positive rate, as does the original article in Nature Medicine. From the sfgate summary:

        It also classified as non-Alzheimer's disease 34 out of 39 who did not have the illness, but nevertheless suffered from other dementias or mild cognitive impairments - 87 percent accuracy.

        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 determ

        • Re: (Score:3, Insightful)

          by pla ( 258480 )
          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 t
          • Well, just make damned sure you HAVE current medical insurance before you get tested for this. I'd be willing to bet this would make it very difficult for you to get insurance at all if you test positive for this...
  • Great, but ... (Score:3, Insightful)

    by Angostura ( 703910 ) on Sunday October 14, 2007 @05:12PM (#20976391)
    I'm not sure I really want to know, given that there is nothing I can realistically do to avoid a rather grim fate.
    • Re:Great, but ... (Score:5, Insightful)

      by KokorHekkus ( 986906 ) on Sunday October 14, 2007 @05:34PM (#20976531)
      As with all "untreatable" diseases it should be left up to the individual. I can only speak for myself but if I started to have some symptoms I think I would like to know so I could help those close to me when they start to suffer from my disease. As a suffer from Alzheimers I'd wish them to make it as well for me as they can but without putting an extremly heavy burden on them. My "self" would be going and I'd wish them to remember me as my full self, if "I" am not there then they should do as well as they can but I wouldn't want them sacrifice their life for what's left of mine.
      • Re:Great, but ... (Score:5, Insightful)

        by Angostura ( 703910 ) on Sunday October 14, 2007 @06:31PM (#20976847)
        Yours is a intelligent, compassionate and humane response. Mine was selfish and shortsighted. I'm still not sure I'd be able to rise to the standards you set if I ever actually suspected I was in the early stages of dimensia.
        • Re: (Score:3, Insightful)

          by KokorHekkus ( 986906 )
          I spoke only about my intetions and I can not guarantee anyone that I will rise to those standards even if I truly wish I will but without intent we are empty. We learn as we go through life and one of my lessons was my grandmother suffering from dementia: I will always remember her as the strong salt-of-the-earth-woman that I met during the summers who served me wonderful local country food and just loved me for me who I was.

          I did cry when I thought about her as she was and I think she would have appro
        • by achurch ( 201270 )
          It's hard, I'll give you that. I'm not sure if I'd have the courage to find out for myself, but after seeing what it's doing to my grandmother, I think the least I can do is implant the idea in my head that my memory may one day become defective (and hope that if I do succumb, at least that part of my memory remains intact). As long as I was capable of determining that I was in fact losing my mind, I think I could deal with it, and I know it'd be easier on family.
      • by tchdab1 ( 164848 )
        Truth is there are many causes of dementia. Alzheimer's is probably the biggest one for people over a certain age (I don't know what that age is).

        If you know what is causing it you can treat it accordingly and/or prepare for its progress.
        If you find yourself or a loved one suffering from dementia, it will help your planning to get diagnosed.
      • by Pastis ( 145655 )
        I've seen my grand mother suffer 8 years while my grand father slowly became an infant. She then spent almost as much to recover from the pain.

        Personally, if I get this disease, and if there's no known treatment, I hope that I will be diagnosed early enough for me to be able to understand it and hope that I will have the guts to quickly put an end to the misery it would cause to my family.
    • Re:Great, but ... (Score:4, Informative)

      by Firethorn ( 177587 ) on Sunday October 14, 2007 @06:30PM (#20976843) Homepage Journal
      nothing I can realistically do to avoid a rather grim fate.

      Actually, there are treatments available to at least delay Alzheimer's disease. They're in the same situation as AIDs medications a decade ago - not much good for reversing the disease, but capable of delaying or stopping it's progress for years.

      Give it another decade and we might even be able to reverse it's progress - memories not retained will still be lost, but the functionality, and maybe some past memory, be restored.

      I don't know about you, but at this time I'd much rather know, so I could get on the drugs now. It's especially critical for me - I have a family history of Alzheimer's.

      Maybe they'll find a cure before it gets bad. Maybe I'll die of something else. But the drugs, especially given early, can delay the disease by decades.
      • Actually, there are treatments available to at least delay Alzheimer's disease.

        That's correct, there are a couple. They don't work very well at all - likely for several reasons. One of them being that Alzheimer's dementia is hard to differentiate from the other dementias and hard to diagnose early given the background of age-related mental decline.

        A good test - blood or imaging - or more likely a couple of half way decent tests with reasonable sensitivity and specificity would go a long way to helping

        • Darn it all, I thought I mentioned it, somehow it got lost during my editing.

          - Starting the drug regime early is critical for effectiveness.

          It's like the drugs slow/stop the acceleration of the disease, not the rate - If you're losing 1% of your memory a year*, you'll continue to lose that under the drugs - but it won't increase, hopefully, to 10%.

          If they can catch it when that's still .5%, or better yet, 0%, great.

          A good test - blood or imaging - or more likely a couple of half way decent tests with reason
      • by Finite9 ( 757961 )
        In the past, say 5 or 6 years ago, it may have been true that although you could be tested for Alzheimers (why is this news now by the way? You've been able to get tested for at least 5-6 years!), People were ... discouraged ... from doing so, with the argument: "would you want to know, when there is nothing you can do about it?".

        This is no longer true, as there is now medicine available that can hinder the disease in a big way, if not outright, if you catch it early enough. I do not know what age limi
    • by GoMMiX ( 748510 )
      There is an ongoing study [clinicaltrials.gov] with clinical trials in the US testing the use of Huperzine A (a chinese herb) to treat Alzheimer's disease. It's also believed to treat other forms of dementia.

      My family has a long history, on my Father's side, of dementia setting in during the 60's -- so my Father and I both read all the news we can regarding such things.

      In fact, my Father was mentioning a University study today of a herb that not only has been shown in controlled trials to treat the effects of AD but to also r
    • Re: (Score:2, Interesting)

      by Kennon ( 683628 )
      It's really only grim in the first stage. But after it becomes more advanced it is only painful for those around you. To you though it can be like a time machine, or a really great trip. You get to travel back in time and see your kids when they were young. Heck my brother's Grandmother-in-law thought she was a secret agent for for the allies during WWII in Spain during the last year of her life. Which was actually pretty interesting because we know her husband was involved in intelligence in that time peri
    • by caluml ( 551744 )
      Take out huge loans, spend them all, and "donate" money left to your family/friends (to avoid taxes on it) while you still remember things.
    • 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 i
  • Now I can know for sure if I'm going to get an incurable brain degenerative disease...
    • Re: (Score:2, Insightful)

      by iknowcss ( 937215 )
      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.
      • Re: (Score:3, Informative)

        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 addit
      • Its not untreatable (Score:5, Informative)

        by mgv ( 198488 ) * <Nospam DOT 01 DO ... veltman DOT org> on Sunday October 14, 2007 @05:51PM (#20976645) Homepage Journal

        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.


        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:

        • Exercise mentally - learning a new language, or other mental exercises, delay the onset.

        • Exercise physically - for reasons that are unclear, physical exercise seems to be protective.

        • Anti-inflammatory drugs (aspirin and non steroidal anti-inflammatory drugs) seem to be protective, and may be worthwhile if you have a high risk of developing the disease


        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 [wikipedia.org]

        Michael
        • And also common marijuana has been shown to been an effective preventative treatment - something about the cannaboids binding and releasing from the brains cannaboid receptors - kind of like cleaning your pipes.
      • Currently, nothing has been scientifically proven to reverse, stop, or even slow the progression of the disease in the brain. Keeping your brain active and using your neural pathways rigorously may help you cope better with the damage that the disease progression does, so if I have X amount of damage but watch Jerry Springer all day, and you have X amount of damage but do crosswords all day, you'll probably be able to work your way around that damage better by finding other ways to say or process or otherwi
      • Lurker187 said it better. but the whole mental workout thing is mostly anti-tiger rocks. Coming from a family with a high rate of alzheimer's, and loving academic pursuits, I really wish it were true. But so far, every study I've seen as a reference to this turns out to have been totally misunderstood by a pop.science journalists.
  • 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.
    • by nbauman ( 624611 )

      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.

      Unfortunately there's no meaningful treatment for Alzheimer's. The FDA-approved drugs will make the difference between a patient being able to name 5 vegetables in a neurological test with the drug and 4 vegetables without the drug. That's what we mean by statistically significant but not clinically significant.

      If you have someone who can't find his way home or is forgetting to turn off the burners on the stove, that person needs to go in some kind of supervised living regardless of what the diagnosis is,

      • by Budenny ( 888916 )
        This is not quite true, in my experience. The difference between taking the drugs and not taking them, is the difference between being in a confused anxious state with no ability to do anything except beg for help over and over again, and sitting quietly reading the paper or a simple book and being able to offer comments about it. Now, this is only palliative - it slows the progress, it does not arrest it. But the benefits, particularly to the carers, are enormous.

        If you have someone with Alzheimers, get
  • by JRHelgeson ( 576325 ) on Sunday October 14, 2007 @05:21PM (#20976453) Homepage Journal
    I always ask my dad "Do you remember the last time you were tested for Alzheimer's?"
    It pisses him off...
  • by dotancohen ( 1015143 ) on Sunday October 14, 2007 @05:26PM (#20976483) Homepage
    ...about Alzheimers is all the new interesting stories on /. every time I refresh.

    (sadly, the same cannot be said about the goatse comments)
  • 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.
  • by Procasinator ( 1173621 ) on Sunday October 14, 2007 @05:46PM (#20976607)
    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!
    • Your comment will, hopefully, be modded up. What you are saying is true and accurate

      My own mother was eighty and growing a bit frail physically, but she still had all her intelligence and mental capacity. She was the target of a "home invasion" type robbery in which she received repeated blows to the head and face. Within a few short weeks she had become far advanced in dementia, and she was battling extreme anger and depression in the bargain. That was three years ago, and it's an endless struggle not to h
      • As one who has also suffered from traumatic brain injury, I am curious as to what the difference is between it and alzheimers actually. Whether the deficits are caused by blunt trauma or by a slow growth of plaque, either way the results are similar. I guess one difference is that most people with traumatic brain injury improve at least somewhat in the first 1-2 years. I know I did. Whereas someone with alzheimers...
        • I think you've stated it. With a head injury there can be improvement. Treatments, therapies, care--all of these will differ in many respects and will have different outcomes. There's also plain old dementia, and it has a whole 'nother set of treatments and outcomes. The doctors wanted to consign my mom to a nursing home two years ago. Her care provider is a unique woman with unique insights. Our joint objective is to keep Mom as active and as engaged as possible, providing her with some sort of quality 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. .... 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!
      ___

      I'd want my brain surgeon to take the test before he begins picking my brain.
    • 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.
  • Big whoop. (Score:5, Informative)

    by Lurker187 ( 127055 ) on Sunday October 14, 2007 @05:57PM (#20976681)
    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 [nih.gov] 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 [nih.gov] reading [nih.gov] for those looking for more info.
    • by epine ( 68316 )
      I term this reverse confirmation bias: if many people have tried and failed, it must be impossible.

      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
    • Re: (Score:3, Interesting)

      by Compuser ( 14899 )
      This is sort of my field too although I am not a doctor but a basic researcher. So there could be three things valuable about this test:
      1. It may be able to give diagnosis earlier.
      2. It may be cheaper and faster than current screening.
      3. When combined with current techniques it may add a few percentages to diagnostic precision. If it is cheap, it will be worth it for that alone.

      From my perspective, #1 is key. We need to find the cause of Alzheimer's and many people (including myself) think that plaques are
      • Right, those would be nice if this test helped with those three aspects, but with all the "developments" that haven't panned out in AD research, I do not make a fuss about this (or anything else) until it's actually proven to be useful. And the fact is, nothing has really supplanted the basic screening yet. But of course, just like in screenings, you need to test out things in order to eliminate them and learn more about what needs to be done.

        So, it's been a couple of years since I've been really up to date
  • I thought FDA stood for Food and Drug Administration. This is a blood test which is neither.
    • Re:FDA Approval? (Score:4, Informative)

      by AugustZephyr ( 989775 ) on Sunday October 14, 2007 @06:54PM (#20976943)

      FDA is the federal agency responsible for ensuring that foods are safe, wholesome and sanitary; human and veterinary drugs, biological products, and medical devices are safe and effective; cosmetics are safe; and electronic products that emit radiation are safe. FDA also ensures that these products are honestly, accurately and informatively represented to the public.
      What the FDA Regulates [fda.gov]

      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 thought FDA stood for Food and Drug Administration. This is a blood test which is neither.
      The U.S. federal government has the power to regulate the sale of medical products either sold in interstate commerce or competing with products sold in interstate commerce. Congress has delegated this authority to the Food and Drug Administration, even for medical products other than drugs. Yes, this makes "Drug" in the agency's title a misnomer.
  • Overfitting...
    • Maybe, and that's what I thought at first, but if you read the full text at Nature Medicine (subscriber only I'm afraid), they've got some good results using their method to predict AD status by analysing samples from two large test sets. I'd like to see it replicated again though, and I'm sure it will be, since blood samples are comparatively easy to get.
  • 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.
    • Does it restore functionality or just prevent further damage?
      • by stox ( 131684 )
        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.
        • Let's hope it works. Some of the things 'medications' are being advertised for are just plain silly. I mean, come on, 'restless leg syndrome'????
  • Why such a fancy test? Drop them off downtown. If they come back it was meant to be.
  • Slashdot: Curing Alzheimers daily since 1997.
  • 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 [guitarworld.com]. Either that
  • ...where's my keys?
  • 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?

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