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Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

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Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#81

Post by rectang »

gfodor wrote: post #72
lthornberry wrote: post #70

HBOT is a widely used 'alternative' treatment for other neurological conditions. It's controversial, in part because there are very good reasons that it can cause neurological damage. This study is NOT a reason for anyone to run out and get HBOT. Even if the effect is real (and I don't think the study has enough info to draw than conclusion), you would need much larger trials to balance benefits and side effects.

If HBOT is potentially beneficial, the proper response to a study is to tell people to raise it to their doctor to see if it makes sense for them.

Lots of treatments are "potentially beneficial", according to various "authorities", such as grapefruit as a cure for cancer. Going outside the scientific consensus is essentially an argument for alternative medicine.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#82

Post by neffy »

tgv wrote: post #68
wheaties wrote: post #62

Earlier quoted context omitted.

6!? They used an N=6 to make such a bold claim? If I had ever thought about that as a sample size for any scientific research my professor would have run me off campus.

I also find it a bit hard to believe that going from 102±7 to 109±5 has a p<0.005. If I run a simple t-test, it says p-value (two-tailed) = 0.07.

Unfortunately a lot of medical science involving expensive laboratory resources and trials currently rests on sample sizes around this range (~5-20). Then whenever there's any kind of technical innovations that makes it cheaper to collect the biosignals there is a sudden series of breakthroughs in what is really happening. All science is a work in progress.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#83

Post by naasking »

robbiep wrote: post #40
zzt123 wrote: post #29

Thoughts that popped up: 1. Isn’t hyperbaric therapy used by athletes to reduce inflammation? 2. Isn’t the failure of the amyloid hypothesis leading to researchers considering whether inflammation is the progenitor of Alzheimer’s? So if hyperbaric therapy does work… could that be a sign in favor of the inflammation hypothesis? Although, the authors suggest the results are due to improved oxygenation rather than any a…

The amyloid hypothesis is not dead - just like the tau hypothesis is not dead. The $1m question is what role do the proteins play and at what stage and to what degree

I assume "the amyloid hypothesis" is the hypothesis that plaques cause Alzheimer's. That hypothesis is indeed dead. There are plenty of successful plaque treatments. Basically none of them are effective.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#84

Post by light_hue_1 »

Another horrific failure of reviewers.

6 subjects!? Did anyone actually check the study they registered? https://clinicaltrials.gov/ct2/show/NCT02790541

Their actual clinical trial had 62 subjects and it had a control arm. The paper has only 6 subjects and no controls.

If I run an experiment with 60 people, I can find evidence for anything (precognition, telekinesis, etc.) if I'm allowed to cherry pick 6 data points and drop any controls.

The authors should be ashamed for polluting the scientific record with this junk.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#85

Post by hervature »

tgv wrote: post #68
wheaties wrote: post #62

Earlier quoted context omitted.

6!? They used an N=6 to make such a bold claim? If I had ever thought about that as a sample size for any scientific research my professor would have run me off campus.

I also find it a bit hard to believe that going from 102±7 to 109±5 has a p<0.005. If I run a simple t-test, it says p-value (two-tailed) = 0.07.

It is a paired t-test as the test takers are the same individuals. This is confirmed in the statistical analysis section of the actual paper. Paired t-test have more statistical power because we don't correct for group variation (as they are the same group measured twice).

Edit: One way to think about this is assuming the effects are random and symmetric then the probability of going up is 1/2. If all 6 participants had increased scores, then the p-value is at least 1/2^6 and this is not taking into account the magnitude of the shift.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#87

Post by criddell »

naasking wrote: post #83
robbiep wrote: post #40

Earlier quoted context omitted.

The amyloid hypothesis is not dead - just like the tau hypothesis is not dead. The $1m question is what role do the proteins play and at what stage and to what degree

I assume "the amyloid hypothesis" is the hypothesis that plaques cause Alzheimer's. That hypothesis is indeed dead. There are plenty of successful plaque treatments. Basically none of them are effective.

Is Wikipedia wrong? They say this:

> Alzheimer's disease is believed to occur when abnormal amounts of amyloid beta, accumulating extracellularly as amyloid plaques, and tau proteins, accumulating intracellularly as neurofibrillary tangles, form in the brain affecting neuronal functioning and connectivity, resulting in a progressive loss of brain function.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#88

Post by parliowl »

jinto36 wrote: post #61
parliowl wrote: post #49

Earlier quoted context omitted.

I skimmed the article for the pertinent table. Three observations: 1. There is no control group. Since people get better with cognitive tests with practice, we don’t know whether these improvements were due to the treatment or just the normal practice effect. (Though if I were a betting person, my money is on the latter.) 2. Cognitive tests are not noiseless. The same person may vary by a few points between repeated…

While a control group is essential to determine if the effect is really due to the treatment or to practice, if they did the mouse study first and expected a positive effect, then they might have felt pressure to only have a human treatment group in what looks like a pilot trial. Maybe their original proposal included a control group, but their institutional review board decided against it? I'm a little surprised the…

I don’t want to speculate about why they designed their study this way or that way, because who knows.

I do feel confident in saying that Scientifically, the human data in this study are largely uninformative.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#89

Post by parliowl »

light_hue_1 wrote: post #84

Another horrific failure of reviewers. 6 subjects!? Did anyone actually check the study they registered? https://clinicaltrials.gov/ct2/show/NCT02790541 Their actual clinical trial had 62 subjects and it had a control arm. The paper has only 6 subjects and no controls. If I run an experiment with 60 people, I can find evidence for anything (precognition, telekinesis, etc.) if I'm allowed to cherry pick 6 data points…

it sounds like you are assuming they collected more data than they reported, is there evidence of that? They preregistered to collect 60, but they couldve simply been unable to collect that many (eg COVID).

If it was preregistered perhaps the journal were obligated to publish the results no matter the outcome. Some journals do this ostensibly to combat publication bias.

I didn’t read the whole thing: are the authors actually claiming the human data are informative? If so, that is wrong. But if they are just saying “hey, these are the data!” I wouldn’t be so harsh.

Edit: Just read the methods. Data collection was 2016 to 2020, so COVID probably wasn’t the issue. They were selected for poor memory yet normal cognition in other domains, so it is possible they couldn’t recruit the number of subjects they proposed who met this criteria and also were willing and able to complete the treatment.

I’m now quite confident the memory result is regression to the mean, and therefore nothing to do with the treatment.

I also read the portion of the discussion related to cognition. They are claiming to have found something meaningful (in the human data) when they definitely haven’t.

Re: Hyperbaric oxygen therapy reverses hallmarks of Alzheimer’s disease and dementia

#90

Post by hinkley »

lthornberry wrote: post #70

HBOT is a widely used 'alternative' treatment for other neurological conditions. It's controversial, in part because there are very good reasons that it can cause neurological damage. This study is NOT a reason for anyone to run out and get HBOT. Even if the effect is real (and I don't think the study has enough info to draw than conclusion), you would need much larger trials to balance benefits and side effects.

If the effect is real then would in not indicate that hypoxia is part of the pathology? There might be other ways besides HBOT to increase oxygen delivery to the brain. The data point is the justification for further research grant proposals.
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