alt Hacker NewsThis analogy has a rather fatal flaw, which is that we already know people who've gotten Alzheimer's, and we also know for a fact people will continue to fall victim to it, at a pretty predictable rate. i.e. the detection has already happened! Anyone who was waiting for a potential victim to appear before researching the cure already has all the reasons they need to research it. Detecting whom exactly the next victim is going to be isn't really going to change anything as far as researching a treatment or cure goes. (Unless the person is super important or popular or rich, I guess?)
This is absolutely nothing like the asteroid example, where knowing that anybody is going to fall victim to it would itself be news of astronomical proportions. Previously there was a high chance the event wouldn't happen, and now it seems likely it will, so that entirely change the calculus of your priorities.
This just completely destroys the analogy. (There are other reasons it doesn't fit too, but one is enough.)
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> Detecting whom exactly the next victim is going to be isn't really going to change anything as far as researching a treatment or cure goes.
Your reasoning relies heavily on this statement, which is only true if occurrence is entirely random, which is in most cases not true. A condition can easily mask the cause of the condition and then you have a confounder(-s) that you have no way of controlling. If you can build multiple strata with high risk ratios, you can find baseline similarities and differences in those groups. Early detection is highly important in knowing these confounders in the first place and then controlling for; and as GP mentions allows for more targeted research in treatment. Without this we could easily spend all the research effort on the effect (symptom) of a condition without even approaching treatment of the cause, i.e. prevention.
A very similar thing has happened with the infamous atherosclerotic plaques. AFAIK (correct me if you are aware of any evidence) there is currently no mechanistic model of how these atherosclerotic plaques form. Yet we spend so much effort in lowering the symptomatic side of increased cholesterol/LDL (which has well-known positives) even if there are known metabolic pathways for LDL increase, based entirely on correlational studies, when LDL is not even close to being the best predictor of cardiovascular conditions. LDL just happens to be easy to measure in a blood test and easy to control with oral medication.
Accurate detection in individuals is still important for testing any potential cure. Otherwise you can only do normal population studies over a very long time and pray that you didn't miss on any confounding variables. With this level of accuracy in diagnosing, you can do targeted testing.
In a case like this, it is possible and even substantially likely that a "Cure" represents a treatment you can apply after an early, routine blood test but before clinically significant symptoms arise, to prevent damage from becoming significant enough to represent an illness.
Late-stage Alzheimers', if not every stage, is very likely going to involve microscopic-scale physical damage to brain tissue that is functionally irreversible.
Blowing up an asteroid after you can see it in the sky with your naked eye will not save you.
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It is also possible that what we call "Alzheimers" is actually biochemically five different disorders with distinct etiologies that have the same endpoint, and that it turns out we can cure two of them. Differentiating conditions for a biomedical catch-all category would be essential; "How accurate you can get the tests" is inseparable from this process of definition.
>Detecting whom exactly the next victim is going to be isn't really going to change anything
What if you found for example all the diagnoses happened shortly after an HSV-1 infection? The more information as to what's going on the better, for research at any rate.
It may not change much as far as researching a treatment or cure goes, but it may help with other stuff, like being better prepared for the future, like organizing a health care worker or getting family members to help out or to look out for you, and other stuff, which you might not be able to do at a later stage of Alzheimers.
While there aren't any cures yet, certain treatments and lifestyle strategies may slow its progression, keep quality of life as long as possible and stuff like that for as long as possible. (And the sooner you start with that, the better)
It's less like discovering the asteroid exists, and more like refining its trajectory enough to know where and when to intercept it
Not really. Alzheimer's is about 60% of dementia, and is frequently misdiagnosed without a full workup. As primary care shifts to more poorly trained providers and doc in the box delivery models, you'll get less workups and more misdiagnoses.
A more objective blood test will make for more accurate diagnoses and and better treatment.
Off topic: Would insurance companies carry patients after being detected for Alzheimers?
If you know they’re going to have it twenty years early, then you can try out preventative treatments. You can look at causes. You can get them to put power of attorney in place and prepare for their future.
Why are you so furious about the idea of people knowing?
The reason the test and actually knowing who is likely to develop the disease is useful is that we don't know enough about the early pre-symptomatic stages of Alzheimer's. A lot of research has been focused on purging the plaques which form in the late stages of the disease and thus failed because these seem to be symptomatic rather than causative. The false positives are also very interesting from a research point of view because if someone is testing positive for the disease but it's not progressing this may give us a clue about how to control it.
The other slightly sad fact is that is also quite likely that any curative treatment will need to be started before you start to show symptoms, because the brain has already lost a lot of it's resilience by then.