Featured Research

from universities, journals, and other organizations

Cardiac Deaths Peak In Sleep Hours For Patients With Sleep Apnea

Date:
March 31, 2005
Source:
Mayo Clinic
Summary:
The 20 million Americans who have obstructive sleep apnea (OSA) are more likely to die suddenly of cardiac causes between 10 p.m. and 6 a.m. than during the other 16 hours of the day combined, according to findings of a Mayo Clinic study published this week in the New England Journal of Medicine.

ROCHESTER, Minn. --- The 20 million Americans who have obstructive sleep apnea (OSA) are more likely to die suddenly of cardiac causes between 10 p.m. and 6 a.m. than during the other 16 hours of the day combined, according to findings of a Mayo Clinic study published this week in the New England Journal of Medicine.

Related Articles


This increased risk among patients with OSA is even more striking because it comes when cardiac deaths in the general population are at their low point.

"The cardiac death peak for the general population comes just after waking, from six to noon, which for several reasons is the most vulnerable time for the heart and blood vessels." says Virend Somers, M.D.,PhD., the Mayo Clinic cardiologist who directed the study. "Almost twice as many people die of cardiac causes then, as compared to the midnight to 6 a.m. period. But for patients with obstructive sleep apnea, the peaks were reversed; more than twice as many cardiac deaths came during the sleeping hours."

Apoor Gami, M.D., lead author of the study, examined the death certificates of 112 Minnesota residents who had sleep studies at the Mayo Clinic Sleep Disorder Center between 1987 and 2003 and who died suddenly of cardiac causes. More than half (54 percent) of the 78 OSA patients died between 10 p.m. and 6 a.m., while only 24 percent of the 34 cardiac deaths among non-OSA patients occurred during that period.

OSA is a collapse - like a wet paper straw - of the airway during sleep. It causes the person to stop breathing momentarily, as many as 60 times per hour. This significantly lowers oxygen levels in the bloodstream, elevates nighttime blood pressure and causes heart rhythm disturbances. Dr. Gami pointed out that about a fifth of North American adults have sleep apnea; most remain undiagnosed.

Snoring is often a symptom, as is inability to stay awake during the day. The standard treatment is continuous positive airway pressure (CPAP), a mask worn at night to keep the airway open.

Dr. Gami says the team's findings not only show that patients with OSA are at much higher risk of cardiac death during sleep; they also indicate that the 6 a.m.-noon peak of cardiac deaths in the general population is even higher for those who don't have sleep apnea. "Because so many people have sleep apnea and are more likely to die suddenly during sleep, the early waking hours are even more dangerous for the rest than we had previously realized," Dr. Gami explains. "We clearly have two distinct populations, with opposite times of highest cardiac death risk."

Dr. Somers cautioned that the study could not determine whether OSA raises the overall risk of sudden cardiac death, or whether it simply shifts the risk to the sleeping hours. The researchers also could not tell whether CPAP devices reduced the nocturnal death risk because records of whether they had been used in the days before sudden death were unavailable. Previous studies have proven CPAP effective in OSA symptom relief and in raising nighttime oxygen levels in the blood, however.

"At the very least, the study may help us better understand why people should die in their sleep at all. We now know that persons with sleep apnea have a peak in sudden cardiac death risk at a time when the general population is relatively protected," Dr. Somers concludes. "Because so many are undiagnosed, we should increase our efforts to identify them and provide the appropriate advice and treatment."


Story Source:

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


Cite This Page:

Mayo Clinic. "Cardiac Deaths Peak In Sleep Hours For Patients With Sleep Apnea." ScienceDaily. ScienceDaily, 31 March 2005. <www.sciencedaily.com/releases/2005/03/050329131103.htm>.
Mayo Clinic. (2005, March 31). Cardiac Deaths Peak In Sleep Hours For Patients With Sleep Apnea. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2005/03/050329131103.htm
Mayo Clinic. "Cardiac Deaths Peak In Sleep Hours For Patients With Sleep Apnea." ScienceDaily. www.sciencedaily.com/releases/2005/03/050329131103.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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