This is from 2013. Why has it seen essentially no news coverage? I can't, for instance, easily find it on sites like Science Based Medicine; you'd think they'd have lit up over this.
http://www.neurology.org/content/48/3/626.short
Just another case of HN users clicking on flashy things without stopping to examine the evidence. Some more examples:
- deep brain stimulation: hundreds of upvotes here on stories about this, but then when studies come out showing that it it no better than placebo that story gets 3 upvotes on HN.
- fecal transplants for C dificile: again hundreds of upvotes for stories touting this, but then when it is found to be no better than placebo the story gets no upvotes on HN.
These are just a few examples, but I see this all the time on HN. It makes me a little disappointed in the community and thinking that perhaps I should be hanging out somewhere else instead.
It found no strong evidence of any association for acetaminophen, but the 95% confidence interval on the result is pretty wide. So it doesn't entirely rule out the possibility of there being a relationship, and based on its results alone it's entirely plausible that a test with more statistical power could find that it doubles your risk of Alzheimer's disease. But it could also plausibly find that it has a mild protective effect.
Regardless of which is the case, this study still strongly challenges what's being suggested by TFA. Even a doubling of Alzheimer's risk resulting from a lifetime of acetaminophen use is nothing at all like its suggestion that Alzheimer's is a disease that was unheard of before the development of NSAIDs related to Tylenol.
Minor point: Tylenol isn't an NSAID, nor is the prior drug to which the article links Alzheimer's.
"In addition, we examined use of acetaminophen...No association was found between AD risk and use of acetaminophen"
How do you think 25cf should have handled this differently?
If you're misunderstanding something, don't worry, someone will set you straight.
Citations needed.
[EDIT] You've posted a link now, and the article is behind a paywall. There may be a correlation between that and the fact that it didn't get any upvotes, but we'd need sizable trials to be sure. :)
I hate paywalls for this reason, but I didn't find any non-paywalled versions of the article -- they all just seem to cherry-pick the good result and completely ignore the other one.
> No association was found between AD risk and use of acetaminophen (RR = 1.35; 95% CI: 0.79-2.30), and there was no trend of decreasing risk with increasing duration of use.
Depending on the methodology (no multiple regression?) and the possible association between NSAID and paracetamol intake, there may be a smoking gun, right there :-)
I had no idea DBS is no better than placebo, do you have a source to back it up?
PA-metabolising enzymes are localised in the synaptic areas of the frontal cortex and hippocampus, where F-AD lesions arise. The initiating chemical lesions in liver poisoning comprise covalent binding of a highly reactive product of PA metabolism to proteins; similar events are believed to occur in brain, where alterations in the antigenic profiles of cerebral proteins activate the microglia. β-Amyloid forms, and, like PA itself, induces nitric oxide synthase. Peroxynitrite modifies cerebral proteins by nitrating tyrosine residues, further challenging the microglia and exacerbating the amyloid cascade. Spontaneous reinnervation, N-acetyl cysteine administration and tyrosine supplementation may attenuate the early stages of F-AD development.
That correlation is drawn, as is a correlation between Alzheimer's (and Alzheimer's-like symptoms) and symptoms potentially related to a side effect of a prior drug for which PA is the active metabolite, which was replaced by PA in the market.
> It's not obvious from skimming that the author identifies the cause by which Tylenol allegedly causes Alzheimer's,
Both the CYTOCHROME P450 and PA AND F-AD: EARLY-STAGE CEREBRAL INJURY sections identify particular mechanisms by which PA may cause or contribute to the progression.
Every time I read some book that's critical of something from modern medicine I look up what SBM has to say about it. Because after all I'm not a medical researcher, nor am I omniscient. But what I do know is that every time, without fail, SBM has written a 'debunking' of that book that has nothing to do with the actual arguments or evidence from the book.
If you like SBM then I would propose that it's because you're not reading the actual books or primary sources they're talking about. So everything they say 'sounds correct', but only because you have no basis for actually judging.