Obstructive sleep apnea occurs when the airway collapses or becomes blocked during sleep. This causes a person to have shallow breathing or pauses in breathing during the night. Not only does this cause drowsiness during the day, but it can increase the likelihood of a whole host of other health problems if left untreated.
How is sleep apnea linked to heart disease?
One of the known risk factors for sleep apnea is high blood pressure. Half of the people with sleep apnea will have high blood pressure. It is also linked to obesity, stroke and heart failure. A recent study published in the journal Circulation: Heart Failure found that when sleep apnea becomes severe, it may cause changes in the heart’s shape and function. These changes are similar to those seen in hypertension, and include increased mass, thickening of the heart wall, and reduced ability to pump.
The good news is that treatment with Continuous Positive Airway Pressure (CPAP), which holds the airway open with a sleep mask to prevent obstruction of the airway, can reverse the negative heart changes. Researchers found that after six months of treatment, and once breathing and sleeping was restored to normal, the heart problems dissipated for people who had only sleep apnea and not other disorders.
[SLIDESHOW: 7 Things that Worsen Sleep Apnea]
What about diabetes?
Sleep apnea is also linked to metabolic syndrome and diabetes. One study looked at how sleep apnea may cause metabolic changes that lead to insulin resistance. Researchers analyzed how intermittent lack of oxygen to the body, also known as hypoxia, affected insulin levels in mice. They used catheters to monitor glucose and insulin sensitivity in mice, and then exposed the mice to either seven hours of oscillated oxygen, with a low of 5 percent once a minute, or a constant rate of oxygen at 10 percent. When compared to controls, researchers found that the intermittent hypoxia associated with sleep apnea caused an increase in insulin resistance.
In addition to insulin resistance, sleep apnea has been shown to affect diabetic peripheral neuropathy, which is nerve damage that can develop throughout the body in people with diabetes. Pain, tingling and numbness can occur, although some people experience no symptoms. A recent study published in the American Journal of Respiratory and Critical Care Medicine found that OSA is linked to DPN in patients with type 2 diabetes, and the severity of sleep apnea is associated with the severity of neuropathy.
Researchers evaluated 234 adults with type 2 diabetes during an overnight sleep study. Participants were monitored with a cardio-respiratory device. They found that the sleep apnea could amplify glucose toxicity in patients with type 2 diabetes, which can cause problems with certain tissue in the body.
Is there a link with cancer mortality?
A recent study looked at the connection between sleep apnea and increased risk of dying from cancer. Researchers studied 5,600 patients in sleep facilities in Spain and used an index to measure the severity of their sleep apnea. They found that patients who had oxygen saturation levels lower than 90 percent for more than 14 percent of their sleep had a greater than 50 percent risk of dying from cancer than those people who did not have sleep apnea. They also found that young male patients with sleep apnea had an even higher association with cancer mortality.
The researchers emphasized that they found only an association between sleep apnea and cancer mortality, and not that sleep apnea causes cancer.
[SLIDESHOW: 10 Tips to Improve Women’s Sleep]
What about risk of dementia in women?
A 2011 study found an association between women who have sleep apnea and an increased risk of dementia. The cause could be due to low oxygen intake levels during sleep, which can impair long-term memory, according to the researchers.
Researchers looked at 298 women who, at the start of the study, had no signs of dementia or mild cognitive impairment. Four years after the initial examination, sleep specialists monitored the women’s sleep with special equipment that measured brain activity, heart rhythm, leg movements, air flow, breathing and oxygen levels. Five years later the women were given cognitive tests. They found that 44.8 percent of women who suffered from disordered breathing associated with sleep apnea developed dementia or mild cognitive impairment, compared with 31.1 percent of women who did not have impaired breathing.
What about an overactive bladder in women?
A study presented at the European Respiratory Society’s Annual Meeting in Vienna, has found evidence connecting sleep apnea and overactive bladder in women.
Overactive bladder syndrome is a condition that causes a frequent need to urinate, incontinence and frequent awakening during the night to urinate. Researchers analyzed 72 female patients suspected of having sleep apnea, who had filled out a questionnaire about their bladder control. They found that 62 of the women had sleep apnea, and those in this group had a higher rate of bladder issues compared to those women without sleep apnea.
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Robert George. (2010, May 18). "Sleep Apnea May Increase Insulin Resistance." Medical News Today. Retrieved from http://www.medicalnewstoday.com/articles/188969.php
n.p. (2012, June 15). "Diabetic Peripheral Neuropathy Linked To Obstructive Sleep Apnea." Medical News Today. Retrieved from http://www.medicalnewstoday.com/articles/246679.php
National Diabetes Information Clearinghouse. (2012, June 25). “Diabetic Neuropathies: The Nerve Damage of Diabetes.” National Institutes of Health. Retrieved from http://diabetes.niddk.nih.gov/dm/pubs/neuropathies/index.aspx
n.p. (2012, September 4). "Studies Suggest A Strong Link Between Sleep Apnea And Cancer Mortality." Medical News Today. Retrieved from http://www.medicalnewstoday.com/articles/249842.php
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European Lung Foundation (2012, September 2). Overactive bladder linked to sleep apnea in women. ScienceDaily. Retrieved from http://www.sciencedaily.com/releases/2012/09/120902184917.htm
Published On: September 10, 2012