Evidence that the shingles vaccine prevents a good chunk of dementia cases

Shingles (Herpes zoster) is implicated. The whole 'lifelong nervous system infection' does seem a bit awful. I bet if we chip away at new kinds of herpes viruses, we'll find a fairly drastic reduction in Alzheimers.

"There is mounting evidence that herpes [simplex] leads to Alzheimers", so, HSV1/2 also.

And apparently having APOE4 genome makes it all worse. HSV1+APOE4=12x risk.

https://www.bbc.com/future/article/20181022-there-is-mountin...

EDIT: for clarity, the twitter thread showed that the shingles vaccine drastically reduces risk

Similarly, there is now extemely strong evidence that the Epstein-Barr is causal in multiple sclerosis. The vast majority of people are infected with EB, with most never having symptoms. However, a nonsignificant minority aren't. A large-scale study of data covering 10 million US military service people found that those infected with EB were 32 times more likely to develop MS.

How about HSV-1/2? Combined this virus is present in about 2/3 people in the US, and resides dormant near the brain (with cold sores).

I thought there's already a strong link with HSV and Dementia, is there any more research looking at this virus and a vaccine?

This – a thousand times, this.

I spent 5-6 years dealing with something like long-covid (only it started before covid). It had symptoms that seemed clearly related to an infection, but I also noticed effects that were similar to Alzheimer/dementia. Specifically sundowning.

I would become unthinkably exhausted and my mood would change drastically between the hours of about 5:00 and 8:00pm. Later in the evening, things would magically start clear up and I'd feel closer to normal.

That was, by far, the worst period of my reasonably long life, and it's still not something I'm over, I can just manage it much better. If anyone is dealing with something similar, I'm happy to talk about things that have worked for me.

Ben Recht is skeptical: https://twitter.com/beenwrekt/status/1662124696186544128

This would not explain the precipitous rise in Alzhemier's rates seen in developed countries and mostly in the last few decades. I maintain that alzheimer's is type 3 diabetes.

https://www.medscape.com/viewarticle/975400 is interesting and seems to directly contradict what is claimed here.

"Herpes zoster does not appear to increase dementia risk ― on the contrary, the viral infection may offer some protection, a large population-based study suggests."

Sounds like we should try to eliminate all long term infections just to be sure, even if they seem mild or harmless.

Summary: Wales used a cutoff date in 1933 to set eligibility for the vaccine: born before, ineligible; born after, eligible. The authors analyzed dementia rates in the populations born one week before and one week after and found a significant decrease in the vaccination population born one week after.

Given the unlikelihood of any other salient differences in the two populations (they were all born within 14 days of each other), they conclude that the vaccine had prophylactic effects against dementia and further conclude that Alzheimer’s may be caused by a virus.

The mechanisms of schizophrenia inside the brain also look alot like an inflammation or otherwise a kind of an infection immune system response, though an over-reaction. I'm making a broad characterization, of course.

The parasite toxoplasma gondii was initially noticed to be present in lots of folks with this type of mental illness (and bipolar) but there hasnt been a 100% correlation.

Massive hidden variable possibilities. Scientific discipline has been shitty for so long. It's exhausting. Beyond that, I wouldn't exactly call a 20% reduction evidence of direct cause.

In short:

- Wales imposed an arbitrary hard cutoff (1933-9-2) on shingles vaccine, giving excellent randomization in a natural experiment

- Randomization confirmed by comparison of preëxisting conditions

- Individuals born after Sept 2, 1933 show a noticeable discontinuity in dementia diagnoses compared to those born prior to Sept 2, 1933, as seen in Figure 3

- Analysis indicates a 20% relative risk reduction across several types of dementia from receiving the VZ vaccine.

This is not like the EBV–MS connection: nothing in the stats so far suggests that varicella zoster is essential or nearly so to developing Alzheimer's disease or other dementia, but it is strong evidence that it contributes to the development of dementia.

I see the theory is based on the 2 Sept 1933 birth prior and after. And after meant they were eligible for the shingles vax. But not all born after that date got that vax. So what does the data show for born after 2 Sept and vax vs no-vax?

The no-vax born after 2 Sept should be very similar to born before 2 Sept, yes? Seems odd they didn't cover that base.

I wonder if there’s some kind of connection to the APOE4 genotype?

The most interesting thing that I saw was: "We find strong protective effects of the vaccine for women but none for men, and that this diff is driven by Alzheimer’s (not vascular) dementia."

I've been meaning to get around to getting the shingles vaccine. I was all set to head out the the pharmacy to get it immediately until I read that..

That seems like a big deal!

Related reading on this topic: https://www.hardtowrite.com/pathogens/

At my annual mandatory physical yesterday my doctor told me that there's a new shingles vaccine that's around 90% effective as opposed to the 60-70% effectiveness of the previous vaccine. It's a two-shot vaccine as opposed to the single shot for the old one. I turned it down, but will probably ask for it now. I got the previous vaccine a few years ago, and then got shingles a few months later, although it was a fairly mild case and I assume that the vaccination probably had a positive effect on that outcome. The funny thing is that I recognized the incident as shingles, and called for an appointment immediately and informed them of my suspicion. At my appointment two days later the doctor prescribed some anti-viral pills and said they were best started immediately after recognizing the infection. I started laughing, as did he.

Very interesting. I recently watched the Michael J. Fox documentary(Still) and even he commented on an earlier infection as a teen "could've" been linked to his condition, but we'll never know.

Also having gone through two extended bouts of long covid now, I think it reactivated a family history of rheumatoid arthritis in me temporarily although I've never formally been diagnosed with it or struggled with it.

We're all just walking balls of disease causing germs eh?

This seems like a math artifact caused by splitting into two groups and then curve fitting the two groups separately. Those two curve fits don't line up at the discontinuity but there's no reason to expect that they would.

The image in tweet 8 is really the damning one. It shows a big gap, but if you fitted the entire set it'd be nearly a straight line with a tiny blip caused by the vaccine.

Will be interesting to see the study go through the peer reviewed process & whether it will be published by a journal.

Yet another reason to try to avoid getting infected with diseases. A 'stronger' immune system (which is really only 'stronger' at defending against the disease that you just caught!) isn't worth the risk of long-term side effects from a chronic infection.

Serious déjà vu did I not read about this study a year ago on HN? I can see this is recent in date but can't shake the feeling...

https://pubmed.ncbi.nlm.nih.gov/35434253/ perhaps this

I recently read some speculation that Alzheimer's might be related to prion diseases like wasting and mad cow disease. That's one possible explanation for cattle mutilations also, which is a really weird rabbit hole to go down.

“ By using country-wide data on all vaccinations received, primary and secondary care encounters, death certificates, and patients' date of birth in weeks, we first show that the percentage of adults who received the vaccine increased from 0.01% among patients who were merely one week too old to be eligible, to 47.2% among those who were just one week younger.”

So only 47.2 % of the adults eligible to get the vaccine chose to get it. I am sure that those 47.2% are doing lots of health things right, like paying attention to their vaccine eligibility, for one. I imagine those behavioral differences in the eligible people who chose to get the vax and those who didn’t, could explain this pretty minor reduction in Alzheimer’s.

This would be more interesting if all the eligible adults got the vax, and all the ineligible ones didn’t.

Am I missing something?

I'm not sure if they are aware of all the variables. %20 reduction only on one gender does not make much sense to me.

My question is: What of people who have never had chickenpox in the first place, and have never been vaccinated for it? A substantial fraction, though still merely a fraction, of the UK population is in this category. (Back of napkin calculation, more than a million people aged 60+ in the UK.)

If herpes zoster is a causative factor behind Alzheimer's, and if the vaccine merely dampens the viral load (or some such thing) in people who carry it, then people who have never had it -- and have a HZ viral load of zero -- should exhibit a dramatically lower rate of Alzheimer's.

Maybe it's just me, but the avenue of advertisement of this being Twitter really ups my skepticism.

That said... my mother died with Alzheimers, I never had Chicken Pox as a kid (and I'm 57 now), but when we had our son 23 years ago, I got the vax for it since it didn't exist when I was young.

And have had the shingles vax too, since my dad evidently neither had Chicken Pox either (he didn't remember), and got it in his 80's, and then shingles thereafter. So I'm vaxxed to the hilt.

Conclusion aside, I enjoy reading research finding in this format - straight to evidence, short.

Did a quick Google search, and it appears that this isn't a new hypothesis, and previous studies had conflicting results.

That seems to be relevant and in direct contradiction: https://www.alzheimersresearchuk.org/no-link-between-shingle... While this is only a correlational result, well, while correlation does not mean causation, you really can't have causation without correlation. So it seems there are conflicting results.

Let's see if this new result holds up. FWIW I'll still certainly get my shingles vaccine once I'm old enough to fall into the recommendation. Shingles is known to be a nasty disease, and making it less likely to get is by itself probably more than enough reason to get the vaccine.

For people who have already had chickenpox/shingles, is there any potential benefit from getting the vaccine?

> We found clean, CAUSAL evidence that the shingles vaccine prevents a good chunk of dementia cases. So, could a virus cause Alzheimer’s > YES

Not to be pedantic, but the BCG vaccine is used as treatment for bladder cancer but nobody is claiming that Tuberculosis causes bladder cancer. In order to claim that shingles is causal (rather than that the vaccine affects immune/other function), you would have to fulfill Koch's postulates or measure virus levels in various patients.

The effect is still interesting.

It would be great if people under 50 could get this vaccine without a prescription (in the US), now many years after it has been generally available to boomers.

Biggest fear in life for me is Alzheimer's or something similar. Looks like I'll be getting the shingles vaccine :)

So if I have shingles I'd have less chance to have Alzheimer?

BTW: I had shingles before 50yo and I vaccinated thereafter.

Good reminder to get the shingles vaccine. Never even gotten chicken pox!

I have herpes simplex. Should I get the shingles vaccine?

This has to be one of the worst chain of reasoning I've seen and it is depressing to see this come from a Stanford Professor.

In 1978 a sports columnist joked that the Superbowl could predict the stock market. It went like this: If one of the 16 original National Football League teams — those in existence before the NFL's 1966 merger with the American Football League — won the Super Bowl, the stock market would rise throughout the rest of the year. If a former AFL team won, it would go down. This works with a 74% success rate till 2021. What does this prove? Literally nothing. The fact of the matter is the stock market and games are irreducible complex systems with thousands of factors contributing to their outcome. With such a system you cannot figure anything out empirically because such complexity will bring out thousands of correlations over any timeframe.

There are only 2 ways to make any sense of complex systems (human bodies is also one of the most complex systems we know). One is to have a causal chain of reasoning. For example say identify some protein that causes Alzheimers and we also find that shingles modifies this protein. Something like this would be the gold standard. Now even if this does not work on a person, we can be guided to deduce that some other condition is preventing the vaccine from working or some other protein is also being damaged etc etc.

If we want to be empirical we need a very carefully controlled experiment (which might be impossible even if ethical). We need two identically healthy humans, some way to induce Alzheimers in both of them and then inject one with shingles vaccine and see if it works. The fact is the medical establishment does not trust our ability to find two identically healthy humans, so we instead do this over thousands of people in a hope of extracting a causal relationship (a randomized control trial). Notice the one major aspect in this trial that the professor does not demonstrate? In his trial there is no inducement of Alzheimers or Dementia. Without that this whole exercise is meaningless. He seems to drastically underestimate the complexity of human life, maybe the group before 1933 in his dataset also did not take a host of other vaccines which actually stops dementia and not this to name a simple example.

Even worse he never tells us the number of humans being examined, if its in 100k range maybe there is a small chance that there is something here but I suspect this is in 1k range at which point this whole study is a joke, you can find thousands of correlations in a group as small as 1k humans. Heck even randomized control trials require thousands of people and this is most definitely a much worse trial than this. In what way does this create a “Clean”, “Causal”, “Without confounders” relation is beyond me and to me is a failure of the academic establishment that someone can think like this after becoming a professor in Stanford. I would be shocked if a graduate student talked like this, much less a professor.

Edit: Upon reading the paper this conclusion seems to be based on 5% of women in that period which is roughly 5000 women. Needless to say there can be thousands of similarities between these 5000 women that is not explained by the vaccine.