[2muchcoffeeman]

> It's not facetious. It's quite the stretch to say that if you assume literally any injection could cure any disease, it's OK to describe any found correlation as a "link".

I don't see it that way. Nick Cage has nothing to do with Alzheimers. We're not finding correlations with Nick Cage movies and then saying "Nick Cage linked to reduction in Alzheimers".

They are suggesting that flu vaccination may have some 2nd order effect beyond protecting you from the flu. Which could be reasonable, science reporting and poor research notwithstanding.

Either way, the refrain "Correlation does not imply causation" is over used in my view. And I'd rather learn the specific ways the research is flawed.

[native_samples]

It could be reasonable but like I said, it's a massive stretch. Flu vaccines are not designed to stop Alzheimer's. There is no argued or known biological pathway through which that might happen. Alzheimer's experts have not previously identified flu vaccines as doing anything that might help. And it probably isn't flu itself causing Alzheimer's because, as I've noted elsewhere in this thread, flu vaccines don't appear to have actually reduced overall flu mortality and some studies show negative effectiveness.

https://www.healio.com/news/primary-care/20200302/flu-vaccin...

I don't think there's a really killer argument here in the abstract: I personally find it unreasonable to imply causation from any medical intervention to any possible outcome based on just a correlation. Yes, it's more reasonable than Nick Cage being associated, but not reasonable enough. That's a judgement call however. I am guided in it by the massive costs and problems created when scientists claim vaccines are miracle cures without sufficiently robust data.

[acdha]

> Flu vaccines are not designed to stop Alzheimer's. There is no argued or known biological pathway through which that might happen.

You might want to read the paper before saying untrue things like that so confidently:

“Mounting evidence indicates that systemic immune responses can have lasting effects on the brain and can influence AD risk and/or progression. A diverse range of microorganisms and infectious diseases have been associated with an increased risk and/or rate of cognitive decline, particularly among older adults, including influenzal respiratory infections [5, 6], pneumonia [4, 7], herpes infections [7], chronic periodontitis [8], urinary tract infections [4], gastrointestinal infections [9], sepsis [4], and most recently COVID-19 [10]. Prevention or attenuation of microbe-related inflammation may therefore represent a rational strategy to delay or reduce the risk of neurodegenerative disease. Consistent with this hypothesis, studies have found a decreased risk of dementia associated with prior exposure to various adulthood vaccinations, including those for tetanus, diphtheria, pertussis (Tdap) [11–13]; poliomyelitis [11]; tuberculosis [14, 15]; herpes zoster (i.e., shingles) [6, 13, 16, 17]; and influenza [11, 18–21].”

Unlike your Nick Cage theory, this has a clear mechanism and is compatible with the understanding of similar effects.

[native_samples]

That supports my point, no? The paragraph you cited boils down to "there is an association between being less sick and not getting Alzheimer's (i.e. being less sick" + "there seems to be an association between literally any vaccine regardless of mechanism or target and less Alzheimers". These are not specific biological mechanisms of action, they're just correlations supported by an ultra-vague causal hypothesis of the form "maybe microbes cause Alzheimers". That's not actually a causal biological explanation.