Obstructive sleep apnea (OSA) is the most common category of sleep-disordered breathing. The muscle tone of the body ordinarily relaxes during sleep, and at the level of the throat the human airway is composed of collapsible walls of soft tissue which can obstruct breathing during sleep. Mild occasional sleep apnea, such as many people experience during an upper respiratory infection, may not be important, but chronic severe obstructive sleep apnea requires treatment to prevent low blood oxygen (hypoxemia), sleep deprivation, and other complications. The most serious complication is a severe form of congestive heart failure called cor pulmonale.
There are two health conditions which go hand-in-hand with one another: sleep apnea and obesity. The problem with them is that each can lead to the other, creating a cycle which is difficult for an individual to break out of. Although CPAP machines (one of the most common methods of treating sleep apnea) are great tools, they aren’t the only treatment required for people with both conditions. Proper treatment for sleep apnea will address both the condition itself and the issue of weight.
Obesity is not always linked with sleep apnea but the presence of it in people who suffer from sleep apnea is very common. The condition is worsened by decreased muscle tone especially if this results in an excess of soft tissue around the face and neck. In plainer terms, if your neck is fat then your breathing can be affected.
Unfortunately it works the other way as well. People with sleep apnea are likely to see an increase in weight even if they aren’t currently obese. The reduction in the workings of all inner systems that is caused by sleep apnea affects the body’s ability to control weight. The individual gains weight and that worsens the sleep apnea problem. Use of a CPAP can greatly assist in gaining control of both problems, but diet and exercise are probably at least as important.
Individuals with low muscle tone and soft tissue around the airway (e.g., because of obesity) and structural features that give rise to a narrowed airway are at high risk for obstructive sleep apnea. The elderly are more likely to have OSA than young people. Men are more likely to suffer sleep apnea than women and children are, though it is not uncommon in the latter two population groups.
Aging and obesity both can contribute to sleep apnea; research suggests the number of people with the condition will grow, as the population ages. Some experts believe that lack of awareness among some patients and doctors has led to underdiagnosis and that the number of patients actually is closer to 30 million.
The risk of OSA rises with increasing body weight, active smoking and age. In addition, patients with diabetes or "borderline" diabetes have up to three times the risk of having OSA.
Common symptoms include loud snoring, restless sleep, and sleepiness during the daytime. Diagnostic tests include home oximetry or polysomnography in a sleep clinic.
Some treatments involve lifestyle changes, such as avoiding alcohol or muscle relaxants, losing weight, and quitting smoking. Many people benefit from sleeping at a 30-degree elevation of the upper body or higher, as if in a recliner. Doing so helps prevent the gravitational collapse of the airway. Lateral positions (sleeping on a side), as opposed to supine positions (sleeping on the back), are also recommended as a treatment for sleep apnea, largely because the gravitational component is smaller in the lateral position. Some people benefit from various kinds of oral appliances to keep the airway open during sleep. "Breathing machines" like the continuous positive airway pressure (CPAP) may help. There are also surgical procedures to remove and tighten tissue and widen the airway.
As already mentioned, snoring is a common finding in people with this syndrome. Snoring is the turbulent sound of air moving through the back of the mouth, nose, and throat. Although not everyone who snores is experiencing difficulty breathing, snoring in combination with other conditions such as overweight and obesity has been found to be highly predictive of OSA risk. The loudness of the snoring is not indicative of the severity of obstruction, however. If the upper airways are tremendously obstructed, there may not be enough air movement to make much sound. Even the loudest snoring does not mean that an individual has sleep apnea syndrome. The sign that is most suggestive of sleep apneas occurs when snoring stops. If both snoring and breathing stop while the person's chest and body try to breathe, that is literally a description of an event in obstructive sleep apnea syndrome. When breathing starts again, there is typically a deep gasp and then the resumption of snoring.
Other indicators include (but are not limited to): hypersomnolence, obesity BMI >30, large neck circumference (16 in (410 mm) in women, 17 in (430 mm) in men), enlarged tonsils and large tongue volume, micrognathia, morning headaches, irritability/mood-swings/depression, learning and/or memory difficulties, and sexual dysfunction.
The term "sleep-disordered breathing" is commonly used in the U.S. to describe the full range of breathing problems during sleep in which not enough air reaches the lungs (hypopnea and apnea). Sleep-disordered breathing is associated with an increased risk of cardiovascular disease, stroke, high blood pressure, arrhythmias, diabetes, and sleep deprived driving accidents. When high blood pressure is caused by OSA, it is distinctive in that, unlike most cases of high blood pressure (so-called essential hypertension), the readings do not drop significantly when the individual is sleeping. Stroke is associated with obstructive sleep apnea. Sleep apnea sufferers also have a 30% higher risk of heart attack or premature death than those unaffected.
In the June 27, 2008, edition of the journal Neuroscience Letters, researchers revealed that people with OSA show tissue loss in brain regions that help store memory, thus linking OSA with memory loss.Using magnetic resonance imaging (MRI), the scientists discovered that sleep apnea patients' mammillary bodies were nearly 20 percent smaller, particularly on the left side. One of the key investigators hypothesized that repeated drops in oxygen lead to the brain injury.