Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sleep apnea tied to increased risk of stroke

08.04.2010
Even mild sleep apnea puts men in danger

Obstructive sleep apnea is associated with an increased risk of stroke in middle-aged and older adults, especially men, according to new results from a landmark study supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health. Overall, sleep apnea more than doubles the risk of stroke in men. Obstructive sleep apnea is a common disorder in which the upper airway is intermittently narrowed or blocked, disrupting sleep and breathing during sleep.

Researchers from the Sleep Heart Health Study (SHHS) report that the risk of stroke appears in men with mild sleep apnea and rises with the severity of sleep apnea. Men with moderate to severe sleep apnea were nearly three times more likely to have a stroke than men without sleep apnea or with mild sleep apnea. The risk from sleep apnea is independent of other risk factors such as weight, high blood pressure, race, smoking, and diabetes.

They also report for the first time a link between sleep apnea and increased risk of stroke in women. Obstructive Sleep Apnea Hypopnea and Incident Stroke: The Sleep Heart Health Study, was published online March 25 ahead of print in the American Journal of Respiratory and Critical Care Medicine.

Stroke is the second leading cause of death worldwide. "Although scientists have uncovered several risk factors for stroke – such as age, high blood pressure and atrial fibrillation, and diabetes – there are still many cases in which the cause or contributing factors are unknown," noted NHLBI Acting Director Susan B. Shurin, M.D. "This is the largest study to date to link sleep apnea with an increased risk of stroke. The time is right for researchers to study whether treating sleep apnea could prevent or delay stroke in some individuals."

Conducted in nine medical centers across the United States, the SHHS is the largest and most comprehensive prospective, multi-center study on the risk of cardiovascular disease and other conditions related to sleep apnea. In the latest report, researchers studied stroke risk in 5,422 participants aged 40 years and older without a history of stroke. At the start of the study, participants performed a standard at-home sleep test, which determined whether they had sleep apnea and, if so, the severity of the sleep apnea.

Researchers followed the participants for an average of about nine years. They report that during the study, 193 participants had a stroke – 85 men (of 2,462 men enrolled) and 108 women (out of 2,960 enrolled).

After adjusting for several cardiovascular risk factors, the researchers found that the effect of sleep apnea on stroke risk was stronger in men than in women. In men, a progressive increase in stroke risk was observed as sleep apnea severity increased from mild levels to moderate to severe levels. In women, however, the increased risk of stroke was significant only with severe levels of sleep apnea.

The researchers suggest that the differences between men and women might be because men are more likely to develop sleep apnea at younger ages. Therefore, they tend to have untreated sleep apnea for longer periods of time than women. "It's possible that the stroke risk is related to cumulative effects of sleep apnea adversely influencing health over many years," said Susan Redline, M.D., MPH, professor of medicine, pediatrics, and epidemiology and biostatistics, at Case Western Reserve University in Cleveland and lead author of the paper.

"Our findings provide compelling evidence that obstructive sleep apnea is a risk factor for stroke, especially in men," noted Redline. "Overall, the increased risk of stroke in men with sleep apnea is comparable to adding 10 years to a man's age. Importantly, we found that increased stroke risk in men occurs even with relatively mild levels of sleep apnea."

"Research on the effects of sleep apnea not only increases our understanding of how lapses of breathing during sleep affects our health and well being, but it can also provide important insight into how cardiovascular problems such as stroke and high blood pressure develop," noted Michael J. Twery, Ph.D., director of the NIH National Center on Sleep Disorders Research, an office administered by the NHLBI.

The new results support earlier findings that have linked sleep apnea to stroke risk. SHHS researchers have also reported that untreated sleep apnea is associated with an increased risk of high blood pressure, heart attack, irregular heartbeats, heart failure, and death from any cause. Other studies have also linked untreated sleep apnea with overweight and obesity and diabetes. It is also linked to excessive daytime sleepiness, which lowers performance in the workplace and at school, and increases the risk of injuries and death from drowsy driving and other accidents.

More than 12 million American adults are believed to have sleep apnea, and most are not diagnosed or treated. Treatments to restore regular breathing during sleep include mouthpieces, surgery, and breathing devices, such as continuous positive airway pressure, or CPAP. In people who are overweight or obese, weight loss can also help.

These treatments can help improve breathing and reduce the severity of symptoms such as loud snoring and excessive daytime sleepiness, thereby improving sleep-related quality of life and performance at work or in school. Randomized clinical trials to test whether treating sleep apnea lowers the risk of stroke, other cardiovascular diseases, or death are needed.

"We now have abundant evidence that sleep apnea is associated with cardiovascular risk factors and diseases. The next logical step is to determine if treating sleep apnea can lower a person's risk of these leading killers," said Redline. "With stimulus funds, our research group is now developing the additional research and resources to begin answering this important question."

Through funding from the American Recovery and Reinvestment Act, the NHLBI is awarding approximately $4.4 million to Redline to conduct the first NIH-funded comparative effectiveness study of treatments for sleep apnea. In the two-year multi-center pilot study, SHHS researchers and others will compare the cardiovascular effects of adding either CPAP or supplemental oxygen during sleep to standard care in patients with moderate to severe sleep apnea who are at high risk for cardiovascular disease events such as heart attack or stroke.

The SHHS draws on a resource of existing, well‑characterized and established cohort studies of cardiovascular and lung diseases supported by the NHLBI. A cohort is a well‑defined group of participants who share a common background or characteristic and are being followed for an extended length of time. For this study, SHHS researchers add assessment of sleep to data collection in ongoing studies including the Atherosclerosis Risk in Communities (ARIC) Study sites in Washington County, Md., and Minneapolis; the Cardiovascular Health Study (CHS) sites in Sacramento, Calif., Washington County, Md., and Pittsburgh; the Framingham Offspring and Omni cohorts in Framingham, Mass.; the Health and Environment and Tucson Epidemiologic Study cohorts in Tucson, Ariz.; the Strong Heart Study sites in Arizona, Oklahoma, and South Dakota; a Reading Center at Case Western Reserve University in Cleveland, Ohio; and the University of Washington in Seattle (Coordinating Center 1994‑1999). The Johns Hopkins University Bloomberg School of Public Health serves as the Coordinating Center.

###

To interview Dr. Twery, contact the NHLBI Communications Office at (301) 496-4236 or at nhlbi_news@nhlbi.nih.gov. To interview Dr. Redline, contact Christina DeAngelis at (216) 368-3635 or cat41@case.edu.

More information about the Sleep Heart Health Study is available at http://www.clinicaltrials.gov/, search for NCT00005275, or at the SHHS Web site at http://www.jhucct.com/shhs/.

Resources:

Sleep Apnea, http://www.nhlbi.nih.gov/health/dci/Diseases/SleepApnea/SleepApnea_WhatIs.html
Your Guide to Healthy Sleep, http://www.nhlbi.nih.gov/health/public/sleep/healthy_sleep.htm
Media Availability: Severe Sleep Apnea Tied to Increased Risk of Death -- Landmark Study Provides Strongest Evidence to Date, http://public.nhlbi.nih.gov/newsroom/home/GetPressRelease.aspx?id=2657
Sleep Apnea and Risk for Stroke and Death, http://www.nhlbi.nih.gov/new/press/05-11-09.htm
NHLBI Study Shows Association Between Sleep Apnea and Hypertension, http://www.nhlbi.nih.gov/new/press/apr11-00.htm
Profile of Dr. Susan Redline and PHASE II Trial of Sleep Apnea Treatment to Reduce Cardiovascular Morbidity, http://www.nhlbi.nih.gov/recovery/researchers/index.php?id=339

Stroke, http://www.ninds.nih.gov/disorders/stroke/stroke.htm

Part of the National Institutes of Health, the National Heart, Lung, and Blood Institute (NHLBI) plans, conducts, and supports research related to the causes, prevention, diagnosis, and treatment of heart, blood vessel, lung, and blood diseases; and sleep disorders. The Institute also administers national health education campaigns on women and heart disease, healthy weight for children, and other topics. NHLBI press releases and other materials are available online at www.nhlbi.nih.gov.

The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.

NHLBI Communications Office | EurekAlert!
Further information:
http://www.nhlbi.nih.gov

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

Im Focus: Autonomous 3D scanner supports individual manufacturing processes

Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).

Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Fingerprints of quantum entanglement

16.02.2018 | Information Technology

'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers

16.02.2018 | Health and Medicine

Hubble sees Neptune's mysterious shrinking storm

16.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>