The risk of death goes up with the severity of a person's obstructive sleep apnea, according to a new study in Koreans.


The Journal of Clinical Sleep Medicine study[1] is the first to find that sleep apnea severity is linked with death risk in an Asian population, said researchers from Chosun University Hospital, Seoul National University College of Medicine and the Seoul National University Bundang Hospital. Previous studies had only looked at Western populations.


Researchers analyzed data from 2,240 people ages 40 and older with sleep apnea or snoring who visited the Sleep Center of Seoul National University Bundang Hospital at some point between 2003 and 2009. All the study participants underwent a full-night polysomnography testing, through which researchers were able to deduce the number of times they stopped breathing throughout the night due to their sleep apnea. They were then grouped into categories based on sleep apnea severity (no sleep apnea, moderate sleep apnea, moderate sleep apnea and severe sleep apnea).


All the participants who had at least mild sleep apnea (about 1,800 of the participants) were assigned to undergo surgery, CPAP, a mandibular advancement device, or a combination of the three.


The participants were followed up with until Dec. 31, 2011; the average participant was observed for 61.4 months, or a little more than five years. Of those with at least mild sleep apnea, 735 received treatment for the condition; the other 1,065 were not treated either because they refused treatment, they became lost during the follow-up period, they wanted to try losing weight, or they wanted to try sleeping in a different position.


Over the study period, 69 people (3.08 percent of the study group) died. Researchers found that the death rate was higher in the groups of people with more severe sleep apnea, compared with less severe or no sleep apnea. Specifically, 1.81 percent of people with no sleep apnea died over the study period, 2.18 percent of people with mild sleep apnea died, 3.54 percent of people with moderate sleep apnea died and 4.2 percent of people with severe sleep apnea died. Heart disease and strokes were the cause of about a third of the deaths.


Overall, the risk of dying was 2.47 times higher among people with severe sleep apnea compared with people without sleep apnea.



"The present study has a clinical implication that increased mortality, shown in studies in Western countries, is also associated with increased severity of OSA in Asians," the researchers wrote.





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  • Sleep Apnea Increases Risk Of Heart Attack


    The sleep disorder has a number of poor effects on the heart. "It's as if somebody's choking you, so your heart rate goes up, your blood pressure goes up," Charles Czeisler, M.D., the Baldino Professor of Sleep Medicine at Harvard Medical School told <em>Health</em> magazine. "Over time, even your daytime blood pressure is higher." Sleep apnea may be responsible for a third of all cases of <a href="http://www.huffingtonpost.com/2012/03/14/sleep-health_n_1310353.html">high blood pressure</a> in Americans, he told the magazine. A 2007 study showed just how serious these cardiovascular effects of sleep apnea are. The research found that people with sleep apnea were <a href="http://www.sciencedaily.com/releases/2007/05/070520183533.htm">30 percent more likely to have a heart attack</a> or die of any cause over a four to five year period.




  • Sleep Apnea May Increase Depression Risk


    The under diagnosed sleep condition takes a <a href="http://www.huffingtonpost.com/2012/03/30/sleep-apnea-depression-risk_n_1391707.html">serious toll on the mood</a>, according to March research from the CDC. In fact, men with sleep apnea were more than twice as likely and women more than five times as likely to feel hopeless, lose interest in their regular activites and display other signs of clinical depression, Health.com reported. Snoring did not seem to be associated with depression. Luckily, the very same <a href="http://www.huffingtonpost.com/2012/06/15/sleep-apnea-treatment-depression-cpap_n_1597703.html">treatment for sleep apnea may also ease depression</a>, according to Cleveland Clinic research.




  • Sleep Apnea May Be A Risk Factor For Diabetes


    There is a growing body of research supporting a link between the presence of sleep apnea and <a href="http://www.huffingtonpost.com/2012/05/24/sleep-apnea-diabetes-type-2-_n_1539933.html">metabolic disorders like diabetes</a>, HuffPost reported in May. Both moderate and severe obstructive sleep apnea were found to be predictors of the disease. A previous study found that people with sleep apnea had more than <a href="http://news.yale.edu/2007/05/24/sleep-apnea-increases-risk-heart-attack-and-diabetes">double the risk of developing diabetes</a>.




  • Sleep Apnea May Increase Cancer Risk


    Not only do people with sleep apnea have a <a href="http://well.blogs.nytimes.com/2012/05/20/sleep-apnea-tied-to-increased-cancer-risk/">higher risk of developing cancer</a>, but they also have a higher risk of dying from the disease, the <em>New York Times</em> reported. Two studies in May examined this link. One found people with sleep apnea had a 65 percent higher change of developing any kind of cancer. The second found that disordered breathing contributed to a five-times higher rate of dying from the disease.




  • Sleep Apnea May Sap Your Libido


    Excessive sleepiness is certainly enough to kill the mood, but research suggests that sleep apnea in particular has an effect on sexual function in both men and women. It may <a href="http://well.blogs.nytimes.com/2011/10/10/really-the-claim-sleep-apnea-causes-sexual-problems/">drive down sex hormones</a> like testosterone in a way that can extinguish the flame for women and cause erectile dysfunction in men, according to the <em>New York Times</em>. And while the typical treatment -- a CPAP machine -- is not exactly an aphrodisiac, Dr. Michael J. Breus writes, it can help not only with sleep apnea, but <a href="http://www.huffingtonpost.com/dr-michael-j-breus/sleep-apnea_b_1661687.html">with the sexual side effects as well</a>.




  • Sleep Apnea May Increase Stroke Risk


    Researchers have long studied the link between the sleep disorder and the risk of stroke, but a small recent study found that 51 of 56 stroke patients evaluated -- or <a href="http://www.huffingtonpost.com/dr-michael-j-breus/sleep-apnea_b_1342311.html">91 percent of patients</a> -- had sleep apnea, Dr. Michael J. Breus wrote for HuffPost. More research is still needed to determine just what role disrupted breathing plays in this elevated risk.




  • Sleep Apnea Increases Accident Risk


    It's not rocket science -- excessive sleepiness during the day leads to sleepier drivers who are at a higher risk of crashing. But a 2008 study found that people with sleep apnea have double the risk of being in a car accident and are <a href="http://www.sciencedaily.com/releases/2008/02/080218214401.htm">three to five times more likely to be in a serious crash</a>. The study was the first to examine the severity of car crashes among people with sleep apnea, and found that even mild disordered breathing was linked to increased risk.




  • Sleep Apnea Is Linked To Pregnancy Complications


    Granted, Perry doesn't have to worry about this particular concern. While sleep apnea is often perceived as a problem predominately for men, <a href="http://www.huffingtonpost.com/2012/08/16/sleep-apnea-in-women-may-_n_1779127.html">women are not immune</a>. And, in fact, sleep apnea presents unique complications for women. A recent study found that women with sleep apnea were more likely to develop high blood pressure during their pregnancies, to require a C-section birth and their babies were more <a href="http://www.huffingtonpost.com/2012/09/21/sleep-apnea-in-pregnancy-_n_1903534.html">likely to be admitted to the neonatal intensive care unit</a>.




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