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PET scans show many Alzheimer’s patients may not actually have the disease

washingtonpost.com

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Re: PET scans show many Alzheimer’s patients may not actually have the disease

#61

Post by marcosdumay »

Broken_Hippo wrote: post #46
trimble wrote: post #11

Pet scan: $3000 - $4000 Peanut butter: $3 - $10 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3823377/pdf/nih...

Great. But we'll also have machines that measure out the dosages. And possibly a few controls. Plus we'll have to adjust for folks that have an exceptional sense of smell. And come to think about it, we'll need to make sure we have baseline sensitivity levels at different ages to base the test result on. We'll have to account for folks that have sensitive sense of smells, which could be a large problem for controls.…

We would also have to take into account simple cases of the flu or a cold.

Yet, as long as the errors are overwhelming at the false positive side, it can be used to reduce the number of the more expensive test.

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#62

Post by ErikVandeWater »

ocfnash wrote: post #54
tominous wrote: post #17

Earlier quoted context omitted.

The cost isn't just in dollars though. In a PET scan they inject a radioactive dye into your bloodstream. It "exposes you to around the same amount of radiation that you would receive from the general environment over about three years." [1] The high dollar cost may also be related to newer, more sensitive machines that don't require as much radiation exposure to the patient. [1] https://www.betterhealth.vic.gov.au/h…

And it's not just any old radioactive source, it's a positron emission! I believe the way it works is that the injected source emits positrons as it decays (having swiped them from the vacuum), shortly thereafter, these annihilate with the electrons of your body, and the scanner looks for the signature pair of gamma rays thus created, using the relative time of arrival to determine their common origin in 3-space. Tha…

OK you've sold me. Where do I sign up?

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#63

Post by mirimir »

Beltiras wrote: post #59
mirimir wrote: post #22

I suspect that AD diagnoses are driven largely by caregiver frustration with unhappy old people. Just as ADHD etc diagnoses are arguably driven by caregiver frustration with unhappy young people. The simplest solution is drugging unhappy people to keep them manageable.

Spoken with the privilege of someone having never faced a diagnosis or had a close one diagnosed. One of the best things that happened to me was an adult diagnosis of ADD. Drugs really helped. Knowing what ailed me was a greater relief thou.

Not at all. My bipolar diagnosis was great for me, because it got my depressive episodes treated properly.

But an important distinction is whether medication is a choice, or is imposed by caregivers with legal authority, psychological influence, or whatever. I mean, I chose to take SSRIs for many years. And it made me crazy. Which I eventually realized.

But a ten year old kid who gets put on SSRIs inappropriately? They are screwed, and perhaps permanently.

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#64

Post by mirimir »

maxerickson wrote: post #55
mirimir wrote: post #21

Earlier quoted context omitted.

Indeed. In the US, it does because manufacturers have gamed the system. Through bundled contracting with hospitals etc, for example.

Hospitals pay a couple dollars for IV saline. In fact, manufacturers are required to report such prices annually to the federal government, which bases Medicare payments on the average national price plus 6 percent. The limit for one liter of normal saline (a little more than a quart) went to $1.07 this year from 46 cents in 2010, an increase manufacturers linked to the cost of raw materials, fuel and transportation.…

Thanks. It does seem that, in this case, it's hospitals that are inflating costs. But even so, this is the Medicare reimbursement price. Maybe hospitals are "paying" cash price for saline, with a rebate on some product bundle, which doesn't get allocated properly to their cost basis for saline.

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#65

Post by eigenstuff »

mirimir wrote: post #63
Beltiras wrote: post #59

Earlier quoted context omitted.

Spoken with the privilege of someone having never faced a diagnosis or had a close one diagnosed. One of the best things that happened to me was an adult diagnosis of ADD. Drugs really helped. Knowing what ailed me was a greater relief thou.

Not at all. My bipolar diagnosis was great for me, because it got my depressive episodes treated properly. But an important distinction is whether medication is a choice, or is imposed by caregivers with legal authority, psychological influence, or whatever. I mean, I chose to take SSRIs for many years. And it made me crazy. Which I eventually realized. But a ten year old kid who gets put on SSRIs inappropriately? Th…

I was put on ADHD meds as a 4 (almost 5) year old after my first violin lesson, this was back in the mid-90s. My mom said it was the weirdest thing she'd ever seen: I so badly wanted to sit still and listen because I wanted to learn to play the violin but I literally physically could not do it and became visibly frustrated with myself. And a bad change in meds in 1st grade (because I didn't like the bitter tablets) was enough for my 1st grade teacher to contact my mom about my change in behavior. It was only as an adult that I realized this must have been the few days where I got in trouble and had to sit out during recess, which was humiliating to me. I have anecdotes for days about this kind of stuff.

I am eternally grateful my parents took me to a psychiatrist when they saw some aspect of my behavior wasn't normal and that it was affecting my quality of life, even if I was far too young to know or understand that. I think it was the humane thing to do, 100%.

People talk a lot about how terrible it is that 5 year olds are put on this shit, but extreme cases like mine are out there and they are legitimate. Sometimes things show up early because they're severe enough. It'd be fucked up if 10 year olds on SSRIs was the norm, but I have no doubt that there are rare cases where it'd almost be cruel /not/ to do it. Bipolar can absolutely be diagnosed in children. If you can diagnose it that early, why wouldn't you start treating it? Isn't that what you SHOULD do as a parent?

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#66

Post by tallanvor »

danielbln wrote: post #60
tallanvor wrote: post #56

Earlier quoted context omitted.

Sorry, what? From the site: "Some research suggests that practicing meditation may reduce blood pressure, symptoms of irritable bowel syndrome, anxiety and depression, and insomnia. Evidence about its effectiveness for pain and as a smoking-cessation treatment is uncertain." I see "may" for some things, and "uncertain" for others. Nothing on that page says that it's been "thoroughly proven to be beneficial".

How about this: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4203918/ (mindfulness being a form of meditation)

No, I wouldn't consider that at all definitive as a study, and the authors specifically note the following:

"This study is limited by the lack of a control group or active comparison clinical intervention that would provide a basis for making a stronger inference about how MBSR might modify the behavioral and neural bases of different types of emotion regulation."

So while MBSR may help some people, this tested one specific method and did not include a control group or test against any other treatment methods.

Now, I'm not suggesting that meditation - MBSR or other - can't be helpful for some people (possibly even the majority of people under certain conditions), but it certainly has not been studied enough to show clear benefits compared to other treatment methods.

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#67

Post by caycep »

PeterisP wrote: post #10

Historically, a bunch of symptom-defined diseases (e.g. hepatitis, diabetes, etc) have turned out to actually be a set of different diseases with different causes, different treatments but similar symptoms - and understanding that split has been a big milestone in treating them. This now might be the case for Alzheimer's as well.

prob. AD as defined at the moment is a set of "criteria" based on a number of things like time scales, and also some specific cognitive measures. I've always found things to be a little vague and there's probably a whole spectrum of different biological entities that can do these sort of things to you.

You can throw PETs, CSF tests etc at it but I never really have a high level of confidence calling it.

Basically people lose memory and certain cognitive functions...but anything could really do it.

At the moment the hodgepodge way I fudge it is: if it is a clearly progressive syndrome year over year, with an amnestic memory syndrome (vs. poor attentional state/registration), with language/naming involvement, and evidence of visuospatial neglect/apraxias, I tell them it may "likely" be AD. Otherwise I can't say if it is AD vs. vascular dementia.

There is a paper looking at accuracy of how we call things vs. post-mortem, and it is about 50/50 eyeroll. Sad but this is the limitation of science vs. mother nature at this state in time.

Re: PET scans show many Alzheimer’s patients may not actually have the disease

#68

Post by mirimir »

eigenstuff wrote: post #65
mirimir wrote: post #63

Earlier quoted context omitted.

Not at all. My bipolar diagnosis was great for me, because it got my depressive episodes treated properly. But an important distinction is whether medication is a choice, or is imposed by caregivers with legal authority, psychological influence, or whatever. I mean, I chose to take SSRIs for many years. And it made me crazy. Which I eventually realized. But a ten year old kid who gets put on SSRIs inappropriately? Th…

I was put on ADHD meds as a 4 (almost 5) year old after my first violin lesson, this was back in the mid-90s. My mom said it was the weirdest thing she'd ever seen: I so badly wanted to sit still and listen because I wanted to learn to play the violin but I literally physically could not do it and became visibly frustrated with myself. And a bad change in meds in 1st grade (because I didn't like the bitter tablets) w…

I get that it helped you. But there are concerns about misguided and inappropriate medication of children. It's a complicated issue, I admit. And I admit that I tend toward cynicism. Anyway, this seems like a decent overview: https://www.nimh.nih.gov/about/directors/thomas-insel/blog/2...
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