If it turns out that driving a Prius on Tuesdays slows down Alzheimer’s, a larger pool of subjects would allow us to figure that out.
(There's enough info in the supplemental link on this page to have an LLM do the Bayes math for you.)
The test is optional. Feel free to skip it.
Tell 50 million people they’re likely to have Alzheimer’s then tell them where to donate towards a cure, or treatments to slow it by a decade.
But apparently your odds go above 30% if you live long enough, so if you could test for being in that cohort I think that result would be too common to actually be devastating.
Pharmaceutical companies have spent something like $50 billion on developing Alzheimer's drugs with, well, the most furtive of straw-grasping to show for it. It's probably the most expensive single disease target (especially as things like cancer are families of diseases)... the failure to have good results isn't for lack of money, and merely throwing more money at it is unlikely to actually make progress towards meaningful treatments.
It's also better for people around the Alzheimer's patient, as it will let them understand why someone's personality and behaviours may be changing, and possibly let them be bit more forgiving of such changes. It will also give family more time to plan and understand the health and community services and support are offered wherever they live.
Even though it cannot be reversed or eradicated (yet, let's hope) detection can allow individuals to adopt interventions that help either adjust their lives to better cope with its progression or help mitigate some of the detrimental behavioral consequences. In addition, if you have family to care for it may be impetus to get certain things in order for them before later stages of the disease, etc. It's horrible and bleak, but I could certainly see why one might want to know.
In the lucky case, it can also relieve anxiety. Even though false negatives may still be possible, receiving a negative detection might give people who have anxiety about certain symptoms relief, since they can rule out (rightly or wrongly) a pretty severe disease.
It is frankly shocking to think disease diagnosis would be a useless thing
At a personal level, I've been through this with my grandfather.
I want to know. My family wants to know. I want to prepare because there are things I want to do today that I know I won't be able to do in the future.
In many ways, it's just like many terminal cancer diagnoses. You're going to lose that person, but you have some time.
My grandfather had a "fall" at work, he then left that job, and held down 2 more engineering jobs before he was diagnosed with a stroking condition and subsequent dementia. I got the distinct impression he thought he had more time, but rapidly declined.
If he knew he was short of time before his rapid decline he probably would have done things differently. Like not buying a house he would later have to sell to pay for aged care.
If he knew he was at risk of a workplace accident he probably wouldn't have worked as an after hours safety engineer at a major treatment plant, where if the worst had happened he could have endangered others.
https://www.alzheimers.org.uk/news/2025-11-18/promising-rese...
Getting an accurate diagnosis is always important. Cognitive decline could be caused by other problems, some of which are more treatable than others.
If this test came back negative it would suggest extra testing to rule out other conditions like a brain tumor or hydrocephalus.
It's used to refine clinical diagnosis after patients present with cognitive severe decline.
By the time someone gets this test, they have severe problems. The purpose of this test is to assist with the right diagnosis.
If you have a prevalence of 10 in 1000, how do the numbers shake out?
Well, you test all 1,000. If we assume a 95% accuracy for false-positive and false negatives?
Of the 990 that you test that don't have the disease, the test will false state 50 do have the disease. Yikes!
And of the 10 that do have the disease? You'll miss 1 of them.
It's not terrible. This is a relatively good number. Diagnostics is just terribly difficult.
Spoilers: It's anywhere between 1-15 and 5-30% for false positives and 1-15/5-40 for false negatives. That's imaging, biomarkers, cancer screenings, etc
Like, where do you think the concept of "second opinions" came from? Whimsy? Lets go ask a second doctor if I actually have cancer, it'll be fun!
One of interesting checks in this study might be to check when (if) any of the participants had taken this vax and what the impact might be on an Alzimer's diagnosis.
wglb•2h ago