Another good reason to get the Shingles Vax: ~20% decrease in rel. risk of dimentia

[PedroDaGr8]

This is actually a really cool and well-designed research study. Basically, Wales structured their rollout of the Shingles vaccine by not only setting a lower cutoff age but also establishing an upper cutoff age. This meant that you have a set of people within a few weeks of the upper cutoff who should be basically identical (at the population scale) but one set could receive the vaccine (under 50% did) and one could not (0.01% got the vaccine elsewhere). The upper cutoff part is important because dementia usually occurs later in life.

Before going into the results, I’ll take a moment to explain the difference in absolute and relative risk: If you have a 1.0% chance of something happening, this is a 1.0% absolute risk. If something reduces that chance by 0.5%, that is a 0.5% absolute risk reduction and a 50% relative risk reduction.

Onto the results: For the group eligible for the vaccine as a whole, there was a 1.3% reduction in absolute risk of dementia which correlates to an 8.5% relative risk reduction. When you account for the fact that less than 50% received the vaccine in the eligible group, the relative risk actually scales to roughly a 20% reduction. With these numbers, they double checked their results a few different ways using different approaches to try to account for various potential compounding factors (e.g., people who don’t get shingles tend to see the doctor less so they might not get diagnosed with dementia). Every single time, the numbers came out essentially the same. They even did a similar analysis using data from the UK NHS data and got similar results.

The results from this study aren’t totally surprising. It had been previously observed that people who have multiple bouts of shingles are more likely to have a dementia diagnosis and people who take anti-retroviral medications for an outbreak of shingles are less likely to receive a diagnosis of dementia. These facts being likely what lead them to perform this analysis. What's very interesting is we haven't seen much which impacts dementia risk to this magnitude.

Full Text Article in Nature: https://www.nature.com/articles/s41586-025-08800-x
Summary Article at ArsTechnica: https://arstechnica.com/science/2025...ia-protection/

[bigsky]

Now entering my fourth month of shingles. Isolation, drugs, depression, lack of motion etc, I can see how that correlates to increased risk of dementia.

The anti virals don't necessarily work as neither they nor prednisone had any effect on me despite being administered the day the first bump appeared.

Get the shots. Despite my doctor vowing that they'll never darken my door again, I'm going to as soon as I don't feel it anymore.

[Darrell KSR]

Thanks, Pedro. Appreciate your expertise and sharing knowledge.

[Darrell KSR]

Now entering my fourth month of shingles. Isolation, drugs, depression, lack of motion etc, I can see how that correlates to increased risk of dementia.

The anti virals don't necessarily work as neither they nor prednisone had any effect on me despite being administered the day the first bump appeared.

Get the shots. Despite my doctor vowing that they'll never darken my door again, I'm going to as soon as I don't feel it anymore.

So sorry you're struggling with it, Bigsky. Hopefully the worst is over or will be soon.

As active mentally as you are, I have to believe that mitigates against adverse effects. At least, I hope so.

[PedroDaGr8]

Now entering my fourth month of shingles. Isolation, drugs, depression, lack of motion etc, I can see how that correlates to increased risk of dementia.

The anti virals don't necessarily work as neither they nor prednisone had any effect on me despite being administered the day the first bump appeared.

Get the shots. Despite my doctor vowing that they'll never darken my door again, I'm going to as soon as I don't feel it anymore.

Damn, I am really sorry to hear that Sky! Hope you find some relief soon.

I have a friend in their 40s who recently had a bout of it down their side. They described it as feeling like pouring molten metal down their side. I wouldn't wish it on anyone.

[KSRBEvans]

I had shingles twice in my mid 40s. It was in my hairline running down a branch of the nerve in my scalp. It felt like a constant headache with occasionally getting punched in the head by George Foreman (RIP).

I'd put off getting the shingles vaccine but in the course of learning about this study, I think I'm going to look into it.

[VirginiaCat]

Pedro,

Thanks for this.

Quick (likely fully uneducated ) question. Does a study like this make you more likely to think that Dementia/Alzheimers are more likely viral driven vs inherent internal factors?

[PedroDaGr8]

Pedro,

Thanks for this.

Quick (likely fully uneducated ) question. Does a study like this make you more likely to think that Dementia/Alzheimers are more likely viral driven vs inherent internal factors?

An excellent question!

I think, much like cancer, the answer is that it is the result of a mix of internal and external factors. Kind of like we know that smoking can cause cancer but there are clearly also internal factors because not everyone who smokes, even heavily, gets cancer. In this case, there is clearly a strong viral component but there are also significant internal factors. The majority of cases of dementia/Alzheimers still lack a definitive causal factor.

[bigsky]

From January 15 until, call it tax day, I've been all or partially debilitated.

You can tell from the volume of my posts, that I am coach surfing. 3 grams of tylenol, 300s of gabapentin, oxycontin to sleep at night, 2 of those lidocaine patches. Nerve block docs didn't want my business.

But in the last week, or so, I've been down to 1.5 grams of tylenol and one gabapentin a night. No oxy no lidocaine. Probably more optimistic is my activity level is ten times what it was in the first two months. I'm putting the boat back together, doing yard work, walking the 9000 steps or so of my route, not all of those every day but enough. Still gassed by the later afternoon.

There is NO doubt the combination of illness and drugs is mentally difficult. I have taken to deferring anything until after public meetings. I'd rather hurt than babble.

Again, the need for the Shingrix shots can't be underestimated. Mine might have been long lasting, but it did not threaten my eyesight or hearing the way outbreaks on the head nerves can. And four months is a long time to be miserable.

[PedroDaGr8]

From January 15 until, call it tax day, I've been all or partially debilitated.

You can tell from the volume of my posts, that I am coach surfing. 3 grams of tylenol, 300s of gabapentin, oxycontin to sleep at night, 2 of those lidocaine patches. Nerve block docs didn't want my business.

But in the last week, or so, I've been down to 1.5 grams of tylenol and one gabapentin a night. No oxy no lidocaine. Probably more optimistic is my activity level is ten times what it was in the first two months. I'm putting the boat back together, doing yard work, walking the 9000 steps or so of my route, not all of those every day but enough. Still gassed by the later afternoon.

There is NO doubt the combination of illness and drugs is mentally difficult. I have taken to deferring anything until after public meetings. I'd rather hurt than babble.

Again, the need for the Shingrix shots can't be underestimated. Mine might have been long lasting, but it did not threaten my eyesight or hearing the way outbreaks on the head nerves can. And four months is a long time to be miserable.

Glad to hear you are doing at least a bit better. That's a huge amount of medication, hope your doctor is keeping an eye on your liver/kidneys too. Here's hoping that your health situation continues to improve.