Featured Research

from universities, journals, and other organizations

Daylight Saving Time: Clock-shifts Affect Risk Of Heart Attack

Date:
October 30, 2008
Source:
Karolinska Institutet
Summary:
Adjusting the clocks to summer time on the last Sunday in March increases the risk of myocardial infarction in the following week, according to a new Swedish study. In return, putting the clocks back in the autumn reduces the risk, albeit to a lesser extent.

Adjusting the clocks to summer time on the last Sunday in March increases the risk of myocardial infarction in the following week. In return, putting the clocks back in the autumn reduces the risk, albeit to a lesser extent, according to research in the New England Journal of Medicine.
Credit: iStockphoto/Karen Roach

Adjusting the clocks to summer time on the last Sunday in March increases the risk of myocardial infarction in the following week. In return, putting the clocks back in the autumn reduces the risk, albeit to a lesser extent. This according to a new Swedish study.

Scientists at Karolinska Institutet have examined how the incidence of myocardial infarction in Sweden has changed with the summer and winter clock-shifts since 1987. Their results show that the number of heart attacks, on average, increases by about five per cent during the first week of summer time.

“There’s a small increase in risk for the individual, especially during the first three days of the new week,” says Dr Imre Janszky, one of the researchers behind the study. “The disruption in the chronobiological rhythms, the loss of one hour’s sleep and the resulting sleep disturbance are the probable causes.”

The team also observed that the readjustment back to winter time on the last Sunday in October, which gives us an extra hour’s sleep, is followed by a reduction in the risk of heart attack on the Monday. The reduction for the whole week is, however, less than the increase related to the summer adjustment.

According to the scientists, the study provides a conceivable explanation for why myocardial infarction is most common on Mondays, as demonstrated by previous research.

“It’s always been thought that it’s mainly due to an increase in stress ahead of the new working week,” says Dr Janszky. “But perhaps it’s also got something to do with the sleep disruption caused by the change in diurnal rhythm at the weekend.”

Even though the increase and decrease in risk are relatively small for the individual, the team believes that the study can improve our understanding of how disruptions to diurnal rhythms impact on our health.

“Roughly 1.5 billion people are subjected to these clock-shifts every year, but it’s hard to make any generalised statement about how many heart attacks they can cause,” adds Dr Rickard Ljung, another member of the research team.


Story Source:

The above story is based on materials provided by Karolinska Institutet. Note: Materials may be edited for content and length.


Journal Reference:

  1. Janszky I, Ljung R. Shifts to and from Daylight Saving Time and Incidence of Myocardial Infarction. New England Journal of Medicine, 30 October 2008, 359;18:1966-68

Cite This Page:

Karolinska Institutet. "Daylight Saving Time: Clock-shifts Affect Risk Of Heart Attack." ScienceDaily. ScienceDaily, 30 October 2008. <www.sciencedaily.com/releases/2008/10/081030075647.htm>.
Karolinska Institutet. (2008, October 30). Daylight Saving Time: Clock-shifts Affect Risk Of Heart Attack. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2008/10/081030075647.htm
Karolinska Institutet. "Daylight Saving Time: Clock-shifts Affect Risk Of Heart Attack." ScienceDaily. www.sciencedaily.com/releases/2008/10/081030075647.htm (accessed September 1, 2014).

Share This




More Health & Medicine News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins