FIRE, napping, and SWR

[dory36]

I may need to ask in Firecalc whether you nap or not -- here is something that seems really profound:

http://www.reuters.com/article/oddly...35458820070213

Excerpt:

Those who made it a practice of napping at least three times a week for a minimum of 30 minutes had a 37 percent lower risk of dying from heart disease compared to non-nappers.

[wabmester]

Wake me up once you make the change to FC.

Here's the journal abstract:

link

I wonder if they considered the total time spent sleeping.

[Sandy]

It doesn't look like they controlled for one major confound - personality type. Those who nap are likely not the aggressive go get 'em type A's. Thus, being of a more relaxed nature, less stressed -- could be that better cardiac outcomes follow.

[dory36]

Would be interesting to read the whole article, rather than just the abstract or the news reports.

Sandy -- did you see the whole article? The abstract says "After controlling for potential confounders..." but does not list them.

But in a peer reviewed research journal, I certainly hope they controlled for personality type -- a first year grad student wouldn't get away neglecting such an important factor.

[Caroline]

It doesn't look like they controlled for one major confound - personality type. Those who nap are likely not the aggressive go get 'em type A's. Thus, being of a more relaxed nature, less stressed -- could be that better cardiac outcomes follow.

Good point. Might also be that they have jobs that ALLOW napping and are more restful / less stressful to begin with.

You know... security guards, mattress testers, supreme court justices... that kind of thing.

[TromboneAl]

Great example of how the press misrepresents scientific studies.

The results from the study:

"...siesta [napping] in apparently healthy individuals is inversely associated with coronary mortality"

Results according to news article:

"Regular naps are good for your heart, researchers said on Monday.

A six-year study of nearly 24,000 Greek adults found those who regularly took midday naps lowered their risk of dying from heart disease by more than a third."

Those are two very different things. Study said that napping was associated with lower chance of heart disease. Article said that napping causes you to have lower chance of heart disease.

An equally reasonable (perhaps more probable) interpretation is that Type A, high stress individuals, who tend to have more heart problems, don't take naps.

[cute fuzzy bunny]

Originally Posted by Sandy

It doesn't look like they controlled for one major confound - personality type. Those who nap are likely not the aggressive go get 'em type A's. Thus, being of a more relaxed nature, less stressed -- could be that better cardiac outcomes follow.

DING! DING! DING!

Cause and effect are often mistaken for each other...

I used to count on that in my former career as a bullshitter marketing guy.

[Sandy]

Originally Posted by Caroline

You know... security guards, mattress testers, supreme court justices... that kind of thing.

Don't for get sleep researcher! When I did sleep research they let us take naps whenever we wanted!

Dory, no I didn't see the whole study, but I would hope they controlled for personality, but you never know. And Al nailed it - who knows what we get reading the distilled version.

[TromboneAl]

BTW, the only way to prove causality would be to do an "experiment" rather than a "study." That is randomly assign the people to the nap or non-nap group. The first would be required to take naps, the other prohibited from taking them.

Not going to happen, of course.

[Rich_in_Tampa]

I'll pull the article and give it a look if I find time this week.

There are those who believe (without solid proof) that "mindfulness meditation" does the same; perhaps blood pressure lowering is one factor. Most of this stuff is very hard to study due to unidentified variables, etc. A randomized controlled trial would be impractical, it appears.

There is biologic plausibility here. Evolution-wise, most primates nap after eating. Physiologically, your catecholamines fall with sleep, and these affect heart rate, blood pressure, blood sugar.

Most importantly, I love to nap on weekends at least, and plan to explore that hobby actively in retirement.

[califdreamer]

What are catecholamines?

[Rich_in_Tampa]

Originally Posted by califdreamer

What are catecholamines?

Adrenaline (and related chemicals); think Jolt.

[califdreamer]

Thanks Rich. Now I'm going to take me a nap and lose some of those catecholamines.

[wabmester]

Originally Posted by Rich_in_Tampa

There is biologic plausibility here. Evolution-wise, most primates nap after eating. Physiologically, your catecholamines fall with sleep, and these affect heart rate, blood pressure, blood sugar.

But most people die in their sleep, right? I've heard one theory on this: sleep apnea, which causes all sorts of interesting side-effects, including an increase in corticosteroids.

[Rich_in_Tampa]

Originally Posted by wab

But most people die in their sleep, right? I've heard one theory on this: sleep apnea, which causes all sorts of interesting side-effects, including an increase in corticosteroids.

I don't know if most people die in their sleep. I'd bet at least 8/24 of them do .

Sleep apnea is a whole other issue. Most are morbidly obese, and spend good portions of the night with dangerously low oxygen levels. They get arrhythmias, high blood pressure, and lots of other nasties (if untreated). They die a lot.

[wabmester]

Here's a different study that looks at mortality vs time asleep (including naps):

link

This one says you're more likely to die if you sleep more than 8 hrs/day.

[Rich_in_Tampa]

Originally Posted by wab

This one says you're more likely to die if you sleep more than 8 hrs/day.

... or people that have underlying but unidentified chronic conditions need to sleep longer, or the longer sleepers contained more sleep apnea patients who slept poorly but longer, or the longer night sleeping group had higher cholesterols (they did, in the full article). The study is very flawed - won't bore you with the details.

Maybe there's a reason it got published in the Croatian Medical Journal instead of the Annals of Internal Medicine, or the New England Journal .

[wabmester]

OK, here's one with a million data points published in the US

link

I wasn't looking for these studies per se -- I was actually looking for the percentage of deaths during sleep for a baseline, but I can't easily find it via google....

[cute fuzzy bunny]

Originally Posted by wab

This one says you're more likely to die if you sleep more than 8 hrs/day.

So per Rich's Theorum, that would make the odds 9/24 or 10/24?

Good one Rich...