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.
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.
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.
That's the viewpoint of everyone sensible outside of Alzheimer's research.
Those in it are still throwing billions per year at the idea.
Meanwhile, back in reality, no amyloid-beta drug has had any clinical effect in humans, other than reducing the plaques. But both the shingles and RSV vaccines are proven to reduce Alzheimer's risk.
Which did not stop the FDA from approving a useless anti-amyloid drug, leading to the resignation of several experts, one of whom called it "probably the worst drug approval decision in recent U.S. history" in his resignation letter. [0]
The sad fact is that some people really should. Many people find it far easier to be or become indigent and fall on Medicaid services. If you do not qualify for Medicaid, then there is a real possibility that your insurance carrier will help put you or your caregivers into massive debt for a long-term illness like this.
If you do go into long-term care, Medicaid will probably seize your assets to help pay for everything. For example, a house in your name. They'll use those to pay back what they paid for your care.
So if you're gonna get sick and you're gonna be a burden in your old age, best to plan for leaving this world the way you came in: naked and penniless.
That price difference seems like the key point. A $200 test can plausibly be used to decide who should get further workup; a $1500 test is already competing with the cost of the workup itself
From a medical perspective, what's the point of the initial test or the workup though? Is it just to check a box? If it comes back positive you will be told to exercise, eat well, take sleep seriously, and manage cholesterol. If it comes back negative you will be told to do the same things.
I've seen up close what dying with these kinds of illnesses look like. For me, a positive test would be a sign that it may be time to say my goodbyes and plan my exit.
I do think telling you to get your affairs in order and to arrange for hospice care is probably good for the doctors. They don't want a family coming in with a sudden decline case and all the information about how to pay for it lost, at minimum
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
Do we yet have any good avoidance or mitigation regimes, be they drug or otherwise for people who show positive on a test like this? The alternative is that it lets you put things in place for when you lose agency.
Good as in scientifically proven. Not speculative fantasy.
We don’t currently have any data that shows any clear way to halt or slow Alzheimer’s.
As someone with family affected by this disease, it’s a very personal choice whether you want to know or not, but I wish people understood that there are many things you can do with it, particularly for those who will be there for you if/when it hits.
Taking care of a loved one with this disease is extremely hard, and it’s even harder when they haven’t had any chance to prepare for this eventuality. Stuff like written records of your history (health, life, etc.), clear powers of attorney, and so on.
It also makes things much easier for healthcare professionals.
Just lost my aunt to Alzheimer's this last week. +1 on the hard to take care of bit. They turn into toddlers, then animals, then nothing. It's heartbreaking.
One other piece of advice I would offer is: find a class at your local hospital or similar. I attended a once-a-week for six weeks thing and it made a huge difference in my perception of dealing with someone suffering from dementia and gave me so much more patience/ grace than I would have had otherwise.
The article doesn't explicitly say but presumably you can start taking the anti-amyloid drugs to slow down the progression immediately, there's also lifestyle changes that can be made (most of those would likely benefit most people)
> 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.
Not a doctor or medical scientist, but my understanding is a) the effectiveness of those anti-amyloid drugs as a preventative tool is unclear, and b) they have a pretty scary safety profile.
Clearly the goal is to be able to prevent the disease from progressing or slow it significantly, but are we really there yet even if we have a test?
As someone with a family member taking one of the newest drugs, I can attest that it does seem to meaningfully slow progression — from rapid decline nearly to a halt in my loved one’s case.
The risk of dangerous side effects seems to be much higher for those with APOE4 — before approving the treatment they required among other things a genetic test ruling that out. (There are several other genetic variants that predispose to Alzheimer’s, fwiw.) We were lucky and saw none of the concerning side effects.
Are we “there” yet? Where’s there?
The prognosis after this treatment is a massive improvement over what it would have been at this stage of progression if it had been reached even 5 years ago.
If you can detect the disease even earlier and halt progress at a point where you retain more cognitive function, that’s a huge win — and gives you time to wait it out a bit longer in hope that we’re able to develop a treatment that doesn’t just pause but can reverse progression.
Yeah, I doubt we’re ready yet to administer these drugs to people who are asymptomatic (not to mention how pricey they currently are). But for someone who likely has the genes for it, just _knowing_ would in some ways be a relief.
Yes, there is the FINGERS method. See e.g. https://fbhi.se
For Alzheimer is particular, there are also some drugs now (e.g. Leqembi) that slow down the process, but no cure yet.
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.
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.
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.
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.
If this gets cheap enough and the predictive values hold up in ordinary clinical populations, it could change when people actually get evaluated rather than just how they get evaluated
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.
But hopefully we'll start to have more options and wider approvals for things like 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?
Those in it are still throwing billions per year at the idea.
Meanwhile, back in reality, no amyloid-beta drug has had any clinical effect in humans, other than reducing the plaques. But both the shingles and RSV vaccines are proven to reduce Alzheimer's risk.
I can't think of a good reason why this happened.
[0] https://www.npr.org/2021/06/11/1005567149/3-experts-have-res...
If you do go into long-term care, Medicaid will probably seize your assets to help pay for everything. For example, a house in your name. They'll use those to pay back what they paid for your care.
So if you're gonna get sick and you're gonna be a burden in your old age, best to plan for leaving this world the way you came in: naked and penniless.
I've seen up close what dying with these kinds of illnesses look like. For me, a positive test would be a sign that it may be time to say my goodbyes and plan my exit.
Good as in scientifically proven. Not speculative fantasy.
As someone with family affected by this disease, it’s a very personal choice whether you want to know or not, but I wish people understood that there are many things you can do with it, particularly for those who will be there for you if/when it hits.
Taking care of a loved one with this disease is extremely hard, and it’s even harder when they haven’t had any chance to prepare for this eventuality. Stuff like written records of your history (health, life, etc.), clear powers of attorney, and so on.
It also makes things much easier for healthcare professionals.
https://www.harvardmagazine.com/2025/05/harvard-taxi-drivers...
For some reason, taxi drivers seem to have a dramatically lower risk of it.
https://www.nih.gov/news-events/news-releases/combination-he...
> 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.
Clearly the goal is to be able to prevent the disease from progressing or slow it significantly, but are we really there yet even if we have a test?
The risk of dangerous side effects seems to be much higher for those with APOE4 — before approving the treatment they required among other things a genetic test ruling that out. (There are several other genetic variants that predispose to Alzheimer’s, fwiw.) We were lucky and saw none of the concerning side effects.
Are we “there” yet? Where’s there?
The prognosis after this treatment is a massive improvement over what it would have been at this stage of progression if it had been reached even 5 years ago.
If you can detect the disease even earlier and halt progress at a point where you retain more cognitive function, that’s a huge win — and gives you time to wait it out a bit longer in hope that we’re able to develop a treatment that doesn’t just pause but can reverse progression.
Yeah, I doubt we’re ready yet to administer these drugs to people who are asymptomatic (not to mention how pricey they currently are). But for someone who likely has the genes for it, just _knowing_ would in some ways be a relief.
The only thing you gain is giving people more time to worry and despair.
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.
It would affect my financial and estate planning, and how I'd like to navigate the disease's progression.
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.
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.