brandonb 14 hours ago

This Alzheimer's blood test, PrecivityAD2, is based on the p-tau217 biomarker.

In one recent study, people very high p-tau217 had a 38% chance of progressing to cognitive impairment within 5 years vs 12% for those with low levels. The current tests cost about $200-300, so they're not unreasonable as a screening test. PrecivityAD2 looks to be priced around $1,400-$1,500 so at that price, this specific test likely only makes sense for people with established disease.

  • vintermann 13 hours ago

    That sounds pretty expensive for me for a test with that low accuracy, especially when there's not much you can do different if it comes back high vs. coming back low.

    • brandonb 12 hours ago

      Agreed that we can't do as much as we'd like. There are some general health things that are believed to prevent cognitive decline, such as managing cholesterol, HbA1c, blood pressure, sleep apnea, etc. One phrase I've heard is that cholesterol at age 50 predicts cognitive health at age 70.

      But hopefully we'll start to have more options and wider approvals for things like anti-amyloid drugs.

      • xattt 9 hours ago

        > anti-amyloid drugs

        Isn’t the viewpoint in the last decade that amyloid plaques are likely a finding rather than the underlying cause of Alzheimer’s Disease?

      • computerdork 24 minutes ago

        Hi there. Actually, Leqembi is a 1st gen Alzheimer’s drugs and targets amyloid plaques. But, like other responses, amyloids doesn’t seem to be hugely responsible for Alzheimers, which is why targeting things like tau proteins is being explored.

    • gwbas1c 7 hours ago

      From TFA:

      > Early detection of Alzheimer’s disease is important since the first treatments capable of slowing the progression of the neurodegenerative disease recently became available to patients, and these drugs are more effective when started sooner rather than later. Other promising investigational drugs are in the pipeline.

      A very good friend's wife had Alzheimer's caught early, and the medication she's on stopped its progression. It's much better for her than my family members who had no treatment options.

      • anjel 7 hours ago

        Creatine supplementation is showing some promising indications of being a low cost, mild to moderate intervention https://www.psychologytoday.com/us/blog/the-modern-brain/202...

        • AppleBananaPie 6 hours ago

          Whether this ends up being replicated or not, I love the classic gym bro supplement being studied for its potential benefits to the brain.

          What a time to be alive

          • Alex3917 1 hour ago

            It's going to be replicated because we already know the mechanism of action. That said, many/most people would probably be better off solving the problem more upstream via whatever B-complex vitamins they need based on their bloodwork and DNA methylation variants.

      • Palomides 6 hours ago

        what? there aren't any treatments that stop alzheimers, there are some that help manage symptoms

        • derekja 12 minutes ago

          May not completely stop it, but lecanemab and donanemab are certainly considered to be disease-progression modifying at this point.

      • someothherguyy 5 hours ago

        > the medication she's on stopped its progression

        what medication is that?

      • amluto 4 hours ago

        I am not personally aware of any treatment for which there is particularly compelling evidence that it meaningfully slows progression even when started early. I wish there was.

        It’s also not clear that one can measure progression well enough that an n=1 data point is meaningful. And I’m also far from convinced that very early Alzheimer’s that would progress rapidly enough to be noticeable can be detected with enough specificity to rule out fairly common cases of people who test positive but effectively don’t have the disease.

        Best wishes to your friend’s wife.

        • computerdork 30 minutes ago

          Agreed that that it’s an interesting question on how to detect Alzheimer’s and also how to treat. My Dad is starting to show signs of mild mental impairment (he’s 87) - more forgetful than usual, more confused than usual, not able to work his computer like he used to…

          He has taken a personal interest in preventing dementia and wants to take the first generation Alzheimer’s drugs, specifically leqembi that works on amyloid plaques. And this is definitely a tough choice, because eventhough it does show some slowing of the disease, it has lot of side effects that may not be worth it.

          Personally, I am against it and don’t think it’s worth it as he could do permanent damage to himself. Think he should hang on until the second generation of drugs come out, which should be in the next 1-3 years (there a lot of Alz drugs in the pipeline, but you never know of course if anything will pan out). It’s a tough choice and don’t know if there is a good option at this point.

  • avgDev 5 hours ago

    We can also test for PSEN1, which is 100% accurate in determining early onset alzheimer's disease, quite a it more expensive, so unreasonable as a screening tool unfortunately.

debo_ 39 minutes ago

I work directly in this field (clinically validated digital cognitive tests that characterize cognition, often paired with p-tau blood tests.) Ask me anything, I guess!

willmadden 8 hours ago

Why is the FDA "clearing" something that is completely innocuous like a blood test?

  • komon 8 hours ago

    I think you need FDA clearance to be able to market a test as actually being effective for treatment/prevention etc. For exactly the same reason woo-woo supplements must disclaim that they aren't intended for that purpose

  • forestrywat 7 hours ago

    Because tests aren't completely innocuous? Because tests lead people to make significant medical decisions?

    Look at the supplements world, where grifters are shilling chemicals that cause harm and make radical claims for absurd markups. Or gas station pills. You want those companies making Alzheimer's tests? People going in to a 7-11 and buying a "all illness test card" that tells people they do or don't have degenerative diseases?

    No, it's very very important to ensure tests are actually indicative and ensure they are well made. To do that, a regulating body needs to be involved.

    • willmadden 7 hours ago

      Their doctor should be qualified to make that judgment without a government bureaucracy evaluating the efficacy of the test on their behalf, unless you want to completely destroy the rate of medical breakthroughs. If there's no potential harm from the procedure itself, the government shouldn't be involved at all.

      Imagine if every new AI model had to be "cleared" by a government regulator. The role of government in healthcare evaluation needs to be simplified and streamlined. The liability needs to be shifted to doctor, and if it's a case of charlatanism, that liability should include a lengthy prison sentence.

      • forestrywat 7 hours ago

        There is potential harm. That's the point.

      • dabinat 4 hours ago

        Some doctors absolutely would abuse this. I used to date someone whose sister was an endodontist and there was another endodontist in the building who was making over $1m a year. She ended up seeing one of that endodontist’s patients and realized that the other doctor had been making all that money by giving people medical procedures they absolutely did not need.

        But only another medical professional would know that; the patients were completely oblivious. I said she should blow the whistle but she “didn’t want to rock the boat”. It definitely changed how I feel about doctors. There’s a massive level of trust there, which most doctors will honor but a few will exploit.

      • staticman2 2 hours ago

        > Their doctor should be qualified to make that judgment without a government bureaucracy

        This is like saying AI developers should be qualified to evaluate the effacy of a model without testing the model.

      • geraldcombs 1 hour ago

        You're assuming that everyone has access to a doctor, and that people who do have doctors will visit them instead of just looking at their phone.

  • tantalor 6 hours ago

    Google "what did theranos do" to find out why.

  • snarf21 5 hours ago

    It is largely about insurance reimbursement. Your health insurance won't likely cover something the FDA hasn't cleared.

hn_submit 11 hours ago

These tests are more or less useless because there's no treatment anyway so knowing about it a long time in advance will not lead to any substantial gain. Even slowing the disease isn't within the realm of today's technology. Today's pharmaceutical companies are close to quacks as far as Alzheimer is concerned. We know next to nothing about its origins or even how the disease progresses.

The only thing you gain is giving people more time to worry and despair.

  • alex43578 11 hours ago

    Earlier diagnosis, or at least suspected diagnosis, could make a difference in studying progression, origin, etc.

    Imagine the test is 100% accurate: if you gave it to a group of people, you could then try to make interventions earlier, capture more data about lifestyle before symptoms, etc.

    • hn_submit 6 hours ago

      Patients becoming involuntary guinea-pigs for science? No thanks.

      As long as there isn't a clear root cause found and some real mitigating medicines reach the market I would propose keeping people ignorant as long as we can.

  • CoastalCoder 11 hours ago

    I think I'd want to know.

    It would affect my financial and estate planning, and how I'd like to navigate the disease's progression.

  • isolatedsystem 10 hours ago

    This is an infuriatingly clueless comment. It gives nothing? It allows people to set their affairs in order, and that is an invaluable thing.

    Alzheimers can lead to all kinds of other issues like impulsivity, or aggressiveness. People gambling away their life savings, not knowing that they are even doing it. Doctors unable to intervene due to rights around patient autonomy. All of this has big consequences in the lives of those affected.

    • hn_submit 6 hours ago

      When the symptons set on you'll have plenty of time to wind down your affairs.

      • ted_dunning 1 hour ago

        And much less ability to handle the task.

  • petesergeant 10 hours ago

    These tests are not useless, but I’d agree (from personal experience) that it’s far from clear that everyone should take one.

    There’s a degenerative genetic disease that runs in my family that for various reasons we only found out about ten years ago. To get the test done in the UK for it, you have to go to mandatory genetic counselling where they try to convince you not to get it done. Of four siblings, the two of us who thought initially we’d definitely get it done, we’ve not, and the two who were sure they wouldn’t, have done.

    They try and convince you not to get it done so you don’t end up confusing being tired one morning or tripping with “oh my God it’s starting”.

    Everyone should get their affairs in order, regularly, without needing a test, if they care about their loved ones.