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Association of sleep duration in middle and old age with incidence of dementia

cnn.com

71–80 of 173 posts

Re: Association of sleep duration in middle and old age with incidence of dementia

#71
post #66

I'm screwed then. Due to a mental issue and my sleep paralysis I'm lucky if I sleep 3-4 hours a night as much as I would like to sleep more.

Worrying about sleeping enough is certainly more detrimental to one’s health and well-being than getting too little sleep.

Re: Association of sleep duration in middle and old age with incidence of dementia

#72
post #28

I wonder if there is a very simple effect involving blood flow to the head. When you sleep, you lie horizontally, and so presumably it's easier for blood to circulate through your entire body. Maybe if you don't get enough horizontal time, it leads to head related problems like dementia and hair loss.

Many people who don't sleep enough at night do spend the same time laying down as one with a full night sleep. Many people would spend like 5 hours sleeping and another 2 hours laying down resting.

Re: Association of sleep duration in middle and old age with incidence of dementia

#73

Earlier quoted context omitted.

Are there causal analyses of sleep on those other forms of dementia?

I'm not well versed on different kinds of studies... could you explain the differences between "causal analysis" and whatever the study linked in the article is? They mention a longitudinal study and that the "finding was confirmed in analysis using sleep duration measured by an accelerometer." I assume a causal analysis would also determine the direction of the causality, e.g. if it turns out that people predisposed…

Correct, the study design in the original article cannot answer causal questions (although of course it can generate hypotheses). For example, if an omniscience informed us "actually, people lose sleep in middle age as a consequence of the early stages of dementia", that would make sense as well.

The best causal analysis is interventional, but many times (such as in this case) it would be both extremely challenging and likely hard to do in any ethical fashion (I can't imagine how it could be done, but perhaps someone could).

Short of that, you're left with instrumental variables. Genetics offers a very nice instrumental variable, since the causal arrow largely goes one way if you setup your study design carefully.

That is generally performed as Mendelian randomization, which has several assumptions but, if met, has nice properties. https://en.wikipedia.org/wiki/Mendelian_randomization

Re: Association of sleep duration in middle and old age with incidence of dementia

#74
post #36

Earlier quoted context omitted.

IME, the biggest predictor for people looking younger than their age is exercising and avoiding alcohol. I'm sure sleep is in there since people who do the other 2 normally also sleep ok.

I'd add tobacco use and UV exposure to that list (anecdotal of course).

Constant stress seems the biggest ager. Intermittent stress (even at high levels), punctuated by periods of relexation, doesn't seem as bad.

See: US presidents before-and-after vs corporate CEOs

Re: Association of sleep duration in middle and old age with incidence of dementia

#75
Many forms of dementia destroy dopaminergic neurons, and this process begins much earlier than symptoms of dementia itself manifest. From what I’ve gathered from reading studies across the years, less dopaminergic capacity seems to be associated with less restful sleep.

The conclusions of this study seem to have it backwards. It’s not lack of sleep that causes dementia, it’s early dementia that causes insomnia.

Edit: it’s also possible that a third factor causes both of these. For example, both people low on dopamine and the sleep-deprived are likely to turn to coffee to keep them functional. If they drink too much coffee, they might accidentally poison themselves into dementia, because some of the Harmala alkaloids in coffee are neurotoxic and like to deposit themselves in brain fatty tissues for a long time.

Re: Association of sleep duration in middle and old age with incidence of dementia

#76
post #43

Earlier quoted context omitted.

I’m expecting my first child in June and have sort of been preparing for misery when it comes to sleep. I appreciate you sharing this.

Whatever happens, know that it's ultimately not only up to you. There's quite a bit of luck involved how they are able to cope with the environment and what sleep pattern they prefer. And OT but relevant for every new parent, sorry for giving unsolicited advice. But always remember, whenever it gets tough: "They're not giving you a hard time, they're having a hard time!". That helped me better understand that it's ou…

Thanks for this, it is the first time I’ve shared this here.

This perspective is useful. We have a cat that sometimes does stuff we wish he wouldn’t and now when unexpected stuff happens I’ve come to realize it means something is bothering him, rather than be frustrated by him.

Hopefully that translates.

Re: Association of sleep duration in middle and old age with incidence of dementia

#77
post #50
post #43

Earlier quoted context omitted.

I’m expecting my first child in June and have sort of been preparing for misery when it comes to sleep. I appreciate you sharing this.

It can be rough. But it isn’t rough for all parents all the time. And keep this in mind: A period of bad sleep could be followed by a period of good sleep. Kids aren’t static, their behavior can vary a lot during different development stages. Best of luck!

Thank you.

Re: Association of sleep duration in middle and old age with incidence of dementia

#78
post #43

Earlier quoted context omitted.

I’m expecting my first child in June and have sort of been preparing for misery when it comes to sleep. I appreciate you sharing this.

Good luck bud. Better to be prepared for misery just in case.

I’m trying to treat it like Burning Man. Where if it’s your first time going, you go in with no expectations and as much preparedness as possible.

Re: Association of sleep duration in middle and old age with incidence of dementia

#79
post #9

"However, this study cannot establish cause and effect" is the only part of this article that matters, and it demonstrates the ineptitude of the article writer.

I agree. This sort of article is partly the reason why we so often here something like "science can't make up its mind" or "x is good now but was bad before, and will be bad again soon". Instead of sharing accurate information about the findings of these researchers, news organizations use them to write catchy, clickbait-y articles. Needless to say, researchers are often to blame as well, since they participate in in…

> Needless to say, researchers are often to blame as well, since they participate in interviews using vague language so that they can benefit from the exposure, well aware of the repercussions of their behavior.

Universities also have PR departments that tout their faculty research. I imagine these PR groups contribute to the hype.

Re: Association of sleep duration in middle and old age with incidence of dementia

#80
post #14

So, anyone with kids is probably going to have dementia?

Usually parents can't sleep well only for a year at most, even 6 months old children are sleeping whole nights.

That's not my experience at all. My oldest woke up screaming with nightmares every night until she was 7 years old. That was 7 solid years of my not sleeping through the night.
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