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Light exposure at night predicts incidence of cardiovascular diseases

medrxiv.org

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Re: Light exposure at night predicts incidence of cardiovascular diseases

#81

Post by tuukkah »

jillesvangurp wrote: post #64
ziofill wrote: post #47

How do they know the causal link? Can it be that people who stay up late sleep less and this causes issues, and there being light is only a consequence of staying up late?

Correlation is not the same as causation. The research indicates a correlation. Assuming causation is a classical mistake with any research. In any case, light sensitivity and sleep patterns are well linked. If you live far away from the equator, you are dealing with pretty short nights half of the year. I lived in Helsinki for a while. That can really mess up your sleep though some people manage to adapt. There's a…

In addition, seasonal disorders are equally common in Madrid and Helsinki, so that cannot explain any difference in sleep disorders.

Btw, did you take a D vitamin supplement and use a light therapy lamp in the mornings?

Re: Light exposure at night predicts incidence of cardiovascular diseases

#83

Post by sebastiennight »

dotancohen wrote: post #66
roenxi wrote: post #54

Earlier quoted context omitted.

Eh, you never know with studies. They did this one to serve as a classic counterexample: https://www.bmj.com/content/363/bmj.k5094 You can almost see the grin as they wrote up the results.

To those who don't follow the link. The Beth Israel Deaconess Medical Center ran a trial on parachute use to prevent death and major trauma when jumping from aircraft, and gave half the people jumping a placebo (empty backpack) instead of a parachute. No joke. https://www.bmj.com/content/363/bmj.k5094

This is the best study I've read this year.

The motive behind the study:

> Parachutes are routinely used to prevent death or major traumatic injury among individuals jumping from aircraft. However, evidence supporting the efficacy of parachutes is weak and guideline recommendations for their use are principally based on biological plausibility and expert opinion.

Results :

> Parachute use did not significantly reduce death or major injury (0% for parachute v 0% for control; P>0.9). This finding was consistent across multiple subgroups.

Methodology might have an influence on the result:

> Compared with individuals screened but not enrolled, participants included in the study were on aircraft at significantly lower altitude (mean of 0.6 m for participants v mean of 9146 m for non-participants; PConclusions

> Parachute use did not reduce death or major traumatic injury when jumping from aircraft in the first randomized evaluation of this intervention.

Implications

> Should our results be reproduced in future studies, the end of routine parachute use during jumps from aircraft could save the global economy billions of dollars spent annually to prevent injuries related to gravitational challenge.

Limitations

> However, the trial was only able to enroll participants on small stationary aircraft on the ground, suggesting cautious extrapolation to high altitude jumps.

I can already see the YouTube thumbnails: THIS IS THE STUDY PARACHUTE MAKERS DON'T WANT YOU TO SEE

Re: Light exposure at night predicts incidence of cardiovascular diseases

#84

Post by ethan_smith »

lunarcave wrote: post #7

> including physical activity, smoking, alcohol, diet, sleep duration, socioeconomic status, and polygenic risk Wondering how much of this is due to geography and air quality. City centers have relatively bad air quality and a high amount of ambient lighting at night, compared to non urbanized areas. The cardiovascular effects of poor air quality is arguably well understood.

The study measured personal light exposure via wrist-worn trackers for a week rather than using geographic light pollution data, which would better control for the urban air quality confounding you've identified.

Re: Light exposure at night predicts incidence of cardiovascular diseases

#85

Post by bregma »

dubeye wrote: post #76

I thought this was well established? My cardiologist always asks about sleep, isn't it obvious a darker room makes for better sleep

I do not have sleep problems. I can sleep anywhere, light or dark. It is completely obvious to me that ambient light and sleep are uncorrelated in any way.

Re: Light exposure at night predicts incidence of cardiovascular diseases

#86

Post by bregma »

trollbridge wrote: post #20
croes wrote: post #4

So use the toilet in the dark?

I've always wondered about people who say that... there's enough light (particularly when it's not a new moon) to see to go the bathroom, but maybe my eyes adjust to the light better?

You must live in the city.

Re: Light exposure at night predicts incidence of cardiovascular diseases

#87

Post by adrianN »

cryptonector wrote: post #52
zer00eyz wrote: post #44

Earlier quoted context omitted.

> We need to make it a lot cooler for researchers to not do original research all the time but to do replication and peer review. This should be the work of grad students, not cranking out another paper or slaving for professors. > We should also demand publication of failures -- it's ok to fail, but only if you publish about the failure. I really want to have a journal that just publishes interesting duds. Someone e…

> > We need to make it a lot cooler for researchers to not do original research all the time but to do replication and peer review. > This should be the work of grad students, not cranking out another paper or slaving for professors. But the professors need to arrange for this.

The people paying the professors need to arrange for this

Re: Light exposure at night predicts incidence of cardiovascular diseases

#88

Post by dalmo3 »

roenxi wrote: post #54
frtannar wrote: post #29

Earlier quoted context omitted.

The best thing to do is to take commonly held knowledge and make a study out of it. Maybe the next study could be “live king cobra in the bed results in sleep reduction”. Probably a book and a TED talk to go with it.

Eh, you never know with studies. They did this one to serve as a classic counterexample: https://www.bmj.com/content/363/bmj.k5094 You can almost see the grin as they wrote up the results.

Grin?

> All authors suffered substantial abdominal discomfort from laughter.

Re: Light exposure at night predicts incidence of cardiovascular diseases

#89

Post by renmillar »

pazimzadeh wrote: post #53
cluckindan wrote: post #3

Preprint not peer reviewed. Also: ”A.J.K.P. and S.W.C. are co-founders and co-directors of Circadian Health Innovations PTY LTD.” Lemme guess, looking for funding.

Peer review doesn't tell you if the data is valid or not. they published their methodology and anyone is free to repeat the study. Peer review just checks for obvious errors in study design, asks for more info if needed, and decides whether the paper is a good fit for the journal. Watson and Crick's paper describing the structure of DNA wasn't peer reviewed. if you think they're wrong, try it for yourself and publish…

This creates a perfect setup for manipulation - the high barriers to entry for proper equipment, organization, and funding needed to produce quality reproductions mean that if someone posts fake content that mimics scientific paper formatting and includes all the right academic signals, most people will accept it as legitimate without question.

Re: Light exposure at night predicts incidence of cardiovascular diseases

#90

Post by renmillar »

danielschreber wrote: post #11
lunarcave wrote: post #7

> including physical activity, smoking, alcohol, diet, sleep duration, socioeconomic status, and polygenic risk Wondering how much of this is due to geography and air quality. City centers have relatively bad air quality and a high amount of ambient lighting at night, compared to non urbanized areas. The cardiovascular effects of poor air quality is arguably well understood.

My bet is that cardiovascular problems cause light exposure at night.

Almost believable. You'd probably instinctively want fresh air when your heart's acting up.
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