Daylight saving and heart attacks
Belatedly...brought to my attention by reading Matt Parker's "Humble Pi," the youtube video "Does daylight saving kill people?" from September, 2018. https://www.youtube.com/watch?v=XZGs5Im9f8Q @dashdashado
On 6/24/19 10:40 AM, Arthur David Olson wrote:
That cites a primary study[1] that spawned a bunch of work, recently reviewed by researchers in Italy. Their bottom line is that "These results support the presence of an association between DST and a modest increase of AMI ["heart attack"] occurrence, especially for the spring shift, and with no definite gender specific differences."[2] and "The risks of AMI increases modestly but significantly after DST transitions"[3]. To my mind the more-concerning health effects of daylight-saving time occur not during the twice-yearly transitions, but during the time that DST is in effect - which is the whole year when a location uses "permanent DST". Unfortunately these effects have not been studied as much, although experts are warning us that these effects are worrisomely negative (see, e.g., [4]). [1] Sandhu A, Seth M, Gurm HS. Daylight savings time and myocardial infarction. Open Heart. 2014 Mar 28;1(1):e000019. https://dx.doi.org/10.1136/openhrt-2013-000019 https://openheart.bmj.com/content/1/1/e000019 [2] Manfredini R, Fabbian F, De Giorgi A et al. Daylight saving time and myocardial infarction: should we be worried? A review of the evidence. Eur Rev Med Pharmacol Sci. 2018 Feb;22(3):750-755. https://dx.doi.org/10.26355/eurrev_201802_14306 https://www.europeanreview.org/article/14306 [3] Manfredini R, Fabbian F, Cappadona R et al. Daylight Saving Time and Acute Myocardial Infarction: A Meta-Analysis. J Clin Med. 2019 Mar 23;8(3). https://dx.doi.org/10.3390/jcm8030404 https://www.mdpi.com/2077-0383/8/3/404 [4] Watson NF. Time to Show Leadership on the Daylight Saving Time Debate. J Clin Sleep Med. 2019 Jun 15;15(6):815-817. https://dx.doi.org/10.5664/jcsm.7822 http://jcsm.aasm.org/ViewAbstract.aspx?pid=31589
On Jun 24, 2019, at 1:33 PM, Paul Eggert wrote:
To my mind the more-concerning health effects of daylight-saving time occur not during the twice-yearly transitions, but during the time that DST is in effect - which is the whole year when a location uses "permanent DST". Unfortunately these effects have not been studied as much, although experts are warning us that these effects are worrisomely negative …
The most likely consequence of "permanent DST” is that people will recognize that winter mornings are too dark and health is affected and, over decades, adjust their hours of activity, nullifying the effect. There’s a precedent. Reading The Parable of the Workers in the Vineyard (Matthew 20:1-16 (KJV)), it appears that the modern timekeeping convention is 6 hours in advance of the convention at the time of that writing. Yet people don’t begin their activities at 0100, take their siesta ("6th-hour") break at 0600, or retire at 11:00. We have adjusted to the hours of daylight, regardless of how they’re numbered. — gil
Spanish people life cycle is an obvious modern example for that 在 2019年6月24日週一 23:29，Paul Gilmartin via tz <tz@iana.org> 寫道：
On Jun 24, 2019, at 1:33 PM, Paul Eggert wrote:
To my mind the more-concerning health effects of daylight-saving time occur not during the twice-yearly transitions, but during the time that DST is in effect - which is the whole year when a location uses "permanent DST". Unfortunately these effects have not been studied as much, although experts are warning us that these effects are worrisomely negative …
The most likely consequence of "permanent DST” is that people will recognize that winter mornings are too dark and health is affected and, over decades, adjust their hours of activity, nullifying the effect.
There’s a precedent. Reading The Parable of the Workers in the Vineyard (Matthew 20:1-16 (KJV)), it appears that the modern timekeeping convention is 6 hours in advance of the convention at the time of that writing. Yet people don’t begin their activities at 0100, take their siesta ("6th-hour") break at 0600, or retire at 11:00. We have adjusted to the hours of daylight, regardless of how they’re numbered.
— gil
Another example of other, perhaps overshadowing influences, is Muslim prayer times. For example, at 47.5 degrees north latitude, in Seattle, WA, US: [https://www.salahtimes.com/usa/seattle] - On the June solstice (2019-06-21), the first prayer was at 03:11 PDT (UTC-7; 2 hours before sunrise) and the last prayer was at 23:11 (2 hours after sunset), 20 hours later. - On the prior December solstice (2018-12-21), the first prayer was at 06:20 PST (UTC-8; 1.5 hours before sunrise) and the last prayer was at 17:55 (1.5 hours after sunset), just 11.5 hours later. On Mon, Jun 24, 2019 at 3:48 PM Phake Nick <c933103@gmail.com> wrote:
Spanish people life cycle is an obvious modern example for that
在 2019年6月24日週一 23:29，Paul Gilmartin via tz <tz@iana.org> 寫道：
On Jun 24, 2019, at 1:33 PM, Paul Eggert wrote: To my mind the more-concerning health effects of daylight-saving time occur not during the twice-yearly transitions, but during the time that DST is in effect - which is the whole year when a location uses "permanent DST". Unfortunately these effects have not been studied as much, although experts are warning us that these effects are worrisomely negative …
The most likely consequence of "permanent DST” is that people will recognize that winter mornings are too dark and health is affected and, over decades, adjust their hours of activity, nullifying the effect.
There’s a precedent. Reading The Parable of the Workers in the Vineyard (Matthew 20:1-16 (KJV)), it appears that the modern timekeeping convention is 6 hours in advance of the convention at the time of that writing. Yet people don’t begin their activities at 0100, take their siesta ("6th-hour") break at 0600, or retire at 11:00. We have adjusted to the hours of daylight, regardless of how they’re numbered.
-- Alan Mintz <Alan.Mintz@gMail.com>
On Mon, 24 Jun 2019, Alan Mintz wrote:
Another example of other, perhaps overshadowing influences, is Muslim prayer times. For example, at 47.5 degrees north latitude, in Seattle, WA, US: [https://www.salahtimes.com/usa/seattle] * On the June solstice (2019-06-21), the first prayer was at 03:11 PDT (UTC-7; 2 hours before sunrise) and the last prayer was at 23:11 (2 hours after sunset), 20 hours later. * On the prior December solstice (2018-12-21), the first prayer was at 06:20 PST (UTC-8; 1.5 hours before sunrise) and the last prayer was at 17:55 (1.5 hours after sunset), just 11.5 hours later.
Jewish prayers are similarly affected where the morning prayer times start at about one hour before sunrise and the evening prayer times, about a half hour after sunset. Hence, in the winter months, completing the morning prayer and getting to work on time can sometimes be a challenge. So too, in the summer months, the end of the Sabbath can be somewhat late. _____________________________________ Ephraim Silverberg, CSE System Group, Hebrew University, Jerusalem, Israel. Phone/Fax number: +972-2-5494521
On Mon, 24 Jun 2019 at 17:29, Paul Gilmartin via tz <tz@iana.org> wrote:
To my mind the more-concerning health effects of daylight-saving time occur not during the twice-yearly transitions, but during the time that DST is in effect - which is the whole year when a location uses "permanent DST". Unfortunately these effects have not been studied as much, although experts are warning us that these effects are worrisomely negative …
The most likely consequence of "permanent DST” is that people will recognize that winter mornings are too dark and health is affected and, over decades, adjust their hours of activity, nullifying the effect.
Over decades, yes. I would imagine that, just as the short-term (~week scale) effects of seasonal DST changes has a nullifying effect on the very real hyper-short-term (~fraction of a day scale) effects on heart attack rates, such long-term (~decades scale) adaptation actually nullifies what would be equally real effects on public health in the medium-term (~years scale). In general, society is unlikely to adjust all of its starting times for everything overnight, but the agreement to shift into a more suitable pattern may instead come along gradually. So perhaps at 2 to 20 years out from a permanent offset shift, one could theoretically see the effects of "social jet lag" settle into a society and then work themselves out… although I would think, in that case, the magnitude of those effects on health data would be sufficiently small that they would likely be dwarfed by the broader public health trends of the time. -- Tim Parenti
On 6/24/19 4:15 PM, Tim Parenti wrote:
I would think, in that case, the magnitude of those effects on health data would be sufficiently small that they would likely be dwarfed by the broader public health trends of the time.
One way to tease out the effects of daylight saving time is to look at the health records of people near a time zone boundary, as you get a one-hour civil-time difference for free. As far as I know this sort of work was pioneered in 2011 by Mikhail Borisenkov of the Komi Science Center, who found that in Russia position within a time zone explained 15% of the variability in female breast cancer mortality. Similar results have been found in the US, as I mentioned in 2017 on this mailing list <https://mm.icann.org/pipermail/tz/2017-November/025548.html>. More recently, researchers have used this technique to find that a one-hour time difference suppresses voting by 2-5%. See: Holbein JB, Shafer JP, Dickinson DL. Insufficient sleep reduces voting and other prosocial behaviors. 2019. Nat Hum Behav 3, 492-500. https://doi.org/10.1038/s41562-019-0543-4 So it appears that daylight saving time causes cancer and keeps voters away from the polls, in addition to its other effects.
On Mon, 24 Jun 2019 at 20:06, Paul Eggert <eggert@cs.ucla.edu> wrote:
One way to tease out the effects of daylight saving time is to look at the health records of people near a time zone boundary, as you get a one-hour civil-time difference for free.
This could, of course, be confounded somewhat in boundary cases where there are mixed economic ties. A friend who grew up near the Dearborn/Franklin County line in southeastern Indiana (prior to statewide observance of DST starting in 2006) spoke of his home operating on a combination of "School Time" (EST) and "Fast Time" (EDT) whenever clocks differed. It seems likely that folks faced with such a situation would pick one system as their primary, while simply contending with the apparent seasonal changes in the other. I'd think *that* type of disruption could be just as taxing. As one data point, the Eastern/Central boundary in the US is effectively invisible when it comes to prime-time television broadcasts. Does the "late local news" report coming on an hour earlier affect bed times, and correspondingly when public affairs and activities are conducted in the evenings? If strong ties to the east coast in certain areas were to affect work and school times, too, it would nullify the "social time difference", but the health effects described could actually be exacerbated in the western extremities of a two-hour-wide "cultural time zone". -- Tim Parenti
On 6/24/19 6:51 PM, Tim Parenti wrote:
On Mon, 24 Jun 2019 at 20:06, Paul Eggert <eggert@cs.ucla.edu <mailto:eggert@cs.ucla.edu>> wrote:
One way to tease out the effects of daylight saving time is to look at the health records of people near a time zone boundary, as you get a one-hour civil-time difference for free.
This could, of course, be confounded somewhat in boundary cases where there are mixed economic ties.
Yes, but another way to measure health effects is to look at the difference between local time and local mean time (i.e., how much our clocks are advanced relative to their "natural" time) as a continuous variable that increases gradually as you move across the time zone. Gu et al. studied cancer risk in the US this way, and found that your risk of getting cancer increases as you move east to west across a time zone. In other words, the earlier in the morning that you are awakened artificially, the more likely you'll get cancer. This result can't be explained by artifacts near time zone boundaries. Because this effect has been found in multiple countries, I expect that permanent daylight saving time would significantly increase cancer incidence in the US. Gu F, Xu S, Devesa SS et al. Longitude position in a time zone and cancer risk in the United States. Cancer Epidem Biomarkers Prev. 2017-08-01;26(8):1306-11 http://dx.doi.org/10.1158/1055-9965.EPI-16-1029
On Tue, 25 Jun 2019 at 17:24, Paul Eggert <eggert@cs.ucla.edu> wrote:
This could, of course, be confounded somewhat in boundary cases where there are mixed economic ties.
Yes, but another way to measure health effects is to look at the difference between local time and local mean time (i.e., how much our clocks are advanced relative to their "natural" time)
I'm not arguing that it isn't; I'm simply pointing out that it isn't necessarily the whole story: What "local time" even means to the average person in a locale, as well as how that affects human activities and daily routines, is much more cultural than geographical, and can and does differ across societies. It is not simply the case that all things in life happen with a constant offset if one looks at life on the other side of a boundary. If it were feasible, of course, it would be more meaningful to look at differences between local mean ("natural") time and the actual timing of human activities. Looking at local wall-clock time instead merely provides an approximation of that. But regardless, the effects of the geographical component are indeed fascinating and worth further consideration. -- Tim Parenti
participants (7)
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Alan Mintz -
Arthur David Olson -
Ephraim Silverberg -
Paul Eggert -
Paul Gilmartin -
Phake Nick -
Tim Parenti