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Why do people snore?

Lynn A. D'Andrea, a sleep specialist at the University of Michigan Medical School, explains.

Snoring is the sound produced by vibrating structures of the upper airway, typically during inhalation. Any membranous part of the airway lacking cartilaginous support, including the tongue, soft palate, uvula, tonsillar pillars and pharyngeal walls, can vibrate. When you sleep, muscle tone throughout your body decreases, or becomes hypotonic. This relaxation of the upper airway muscles during sleep may decrease the size of the airway space and cause airflow limitation and turbulence. It is the combination of turbulent airflow through the hypotonic airway structures that results in the harsh vibratory noise known as snoring.

Snoring is not an illness, but it is a symptom. Just as a cough can be a symptom of pneumonia, snoring can be a symptom of obstructive sleep apnea. Obstructive sleep apnea is a disorder characterized by snoring, labored breathing and repetitive obstructed pauses or gasps in a person¿s breathing during sleep. The obstructed pauses result from complete obstruction or blockage of the airway and may be associated with decreases in oxygen levels. Typically, the obstruction is terminated by an arousal¿that is, the snorer briefly wakes up--leading to fragmented, less restful sleep. Obstructive sleep apnea can cause excessive daytime sleepiness, decreased attention and poor concentration, and decreased energy levels. The consequences of these behavioral problems can be quite severe and include motor vehicle accidents if a sufferer becomes inattentive or falls asleep while driving. Obstructive sleep apnea is also causally related to vascular complications such as hypertension. Snoring without evidence of obstructive sleep apnea may be an independent risk factor for hypertension and the daytime behavioral problems mentioned above, but how snoring alone causes problems remains unknown.

The reported prevalence of snoring varies, and depends on the population studied and the wording of the questionnaire. Data from the Wisconsin Sleep Cohort Study found that 44 percent of all men surveyed and 28 percent of all women surveyed were habitual snorers. Overall, 4 percent of these men and 2 percent of these women had snoring that was associated with obstructive sleep apnea. Furthermore, the prevalence of snoring and obstructive sleep apnea seems to increase with age, especially after 65 years of age. Additional risk factors associated with the development of snoring include weight gain, alcohol consumption, allergies, nasal obstruction, use of muscle relaxants or sedatives, and smoking.

Snoring remedies run the gamut from simple, noninvasive devices that open the nasal passages to more invasive surgical procedures. An external nasal dilator, the Breathe RightR brand nasal strip, enhances nasal breathing by attaching to the outside of the nose like a bandage, and gently lifting and opening the nasal passages. A common observation suggests that snoring improves if the person sleeps on his side or in a semi-upright position rather than on his back. To encourage this position, many snorers have tried solutions ranging from sewing a tennis ball to the back of pajamas to propping up on wedge-shaped pillows. Other noninvasive ways to reduce snoring include losing weight, avoiding alcohol and sedatives, and managing any allergic symptoms. Smoking may lead to airway inflammation and swelling that can further narrow the upper airway, thus smoking cessation may improve snoring. Oral appliances and nasal continuous positive airway pressure (nCPAP) devices are mechanical apparatuses that act to prevent the tongue and soft palate from collapsing back into the upper airway. Finally, surgery--previously performed with a scalpel and now with a laser--removes some of the vibratory tissues from the back of the airway. Success rates for this procedure are reported to range from 50 percent to 100 percent, although it is described as quite painful.

Snoring also occurs in children. Researchers have found that 20 percent of normal children snore occasionally and 7 percent to 10 percent of children snore every night. In many cases, children who snore are perfectly healthy, but about 1 percent of children who snore have obstructive sleep apnea. Children with sleep apnea may snore at night and exhibit decreased attention during the day. There is also concern that children with sleep apnea have symptoms similar to those children diagnosed with attention-deficit disorder. In children, the most common cause of sleep apnea is enlarged tonsils and adenoids, and treatment consists of surgical removal of the tonsils and adenoids.

In summary, snoring causes more lost sleep and irritability than most people realize. As novelist Anthony Burgess observed, "Laugh and the world laughs with you; snore and you sleep alone."

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