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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

#51

Post by Spooky23 »

jimjimjim wrote: post #16
philovivero wrote: post #6

This is amazing news. I love the advances we're making as a society. In that $3-5k cost of running a PET scan, I wonder how much of that is paying professional operators and physicians to interpret the results? Could ML be applied to this problem to reduce the cost of a PET scan?

why does an IV bag cost $500? I want professional operators and physicians to look at my details. What I don't want is dozens of layers of middlemen or ticket clippers (or healthcare driven by profit).

Because you're buying a lot of insurance and debt.

The lack of quality health insurance means that a substantial number of people finance healthcare via bankruptcy. That's all priced in. As an insured person or private payer, you pay dramatically more as a result -- it's a hidden tax.

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

#52

Post by mrfusion »

dm319 wrote: post #44

The term 'Alzheimer's' has been politicised. Making a diagnosis requires a brain biopsy, usually done as part of an autopsy. I don't believe a PET scan is capable of making the diagnosis, despite what the article says. To understand what is going on, we have to see the problem that hit clinicians and families around 10-20 years ago. It seemed like an epidemic of confused elderly patients landing on wards without a sp…

Very interesting idea! I've never noticed an increased heart rate during an infection though. That sounds kind of strange.

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

#54

Post by ocfnash »

tominous wrote: post #17
philovivero wrote: post #6

This is amazing news. I love the advances we're making as a society. In that $3-5k cost of running a PET scan, I wonder how much of that is paying professional operators and physicians to interpret the results? Could ML be applied to this problem to reduce the cost of a PET scan?

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. That reduces the problem of scanning to arranging for the decaying source to accumulate in the place we wish to scan which apparently can be done.

That we scan ourselves by annihilating antimatter with our bodies in targeted ways just seems so awesome to me.

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

#55

Post by maxerickson »

mirimir wrote: post #21
duozerk wrote: post #18

Earlier quoted context omitted.

> why does an IV bag cost $500? It doesn't outside of the US.

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.

http://www.nytimes.com/2013/08/27/health/exploring-salines-s...

(which implies that manufacturers aren't the primary beneficiaries of the price that the hospitals charge)

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

#56

Post by tallanvor »

nefitty wrote: post #42
ekianjo wrote: post #40

Earlier quoted context omitted.

> meditate Any clinically proven benefit of meditation though? Don't throw it together with sleep and exercising...

It's been thoroughly proven to be beneficial, in many ways. https://nccih.nih.gov/health/meditation/overview.htm

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".

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

#57

Post by TACIXAT »

ekianjo wrote: post #40
std_throwaway wrote: post #35

Earlier quoted context omitted.

It's not much better than searching for the cure for all illness. Drink enough, sleep enough, eat well, do some sports, meditate. If that doesn't help, good luck with going to the doctors.

> meditate Any clinically proven benefit of meditation though? Don't throw it together with sleep and exercising...

A ton of benefits. It's a very good habit to pick up. Not a wonder drug though.

>In 2013, researchers at Johns Hopkins identified 47 studies that qualify as well-designed and therefore reliable. Based on these studies, they concluded that there is moderate evidence that meditation reduces anxiety, depression, and pain, but there is no evidence that meditation is more effective than active treatment. [1]

1. https://en.wikipedia.org/wiki/Research_on_meditation

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

#58

Post by dm319 »

mrfusion wrote: post #52
dm319 wrote: post #44

The term 'Alzheimer's' has been politicised. Making a diagnosis requires a brain biopsy, usually done as part of an autopsy. I don't believe a PET scan is capable of making the diagnosis, despite what the article says. To understand what is going on, we have to see the problem that hit clinicians and families around 10-20 years ago. It seemed like an epidemic of confused elderly patients landing on wards without a sp…

Very interesting idea! I've never noticed an increased heart rate during an infection though. That sounds kind of strange.

It's seen as fairly basic/text-book knowledge, and finding a paper on it is pretty difficult. It was probably shown in the 19th century and isn't easily found on google scholar! I did find one reference [1] from more recently. Part of our sepsis warning scores depend on the heart rate to rate the severity of the illness. I suspect even in mild colds your cardiac output goes up, but it might be difficult to notice just from measuring the pulse (stroke volume can change).

Heart is just one example - our kidneys get worse as we get older too (see figure 4 of this paper - it's a straight line pretty much [2]). In practice, it doesn't cause us problems in day to day life, but give it a really big insult (like sepsis) and it can decompensate. The difference with kidneys is that we can support kidney failure with dialysis or filtering (if their heart can support that), whereas with cardiac failure this is not so simple.

Brain failure is probably one of the worst forms of failure. Most causes have no cure, and they often require 24hr care.

[1] http://ajpregu.physiology.org/content/246/3/R331.short

[2] https://www.spandidos-publications.com/10.3892/mmr.2015.3292

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

#59

Post by Beltiras »

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.

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

#60

Post by danielbln »

tallanvor wrote: post #56
nefitty wrote: post #42

Earlier quoted context omitted.

It's been thoroughly proven to be beneficial, in many ways. https://nccih.nih.gov/health/meditation/overview.htm

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)

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