1. What is it: This common disorder occurs when throat muscles relax and cause breathing to repeatedly stop or become very shallow. Breathing pauses can last from a few seconds to minutes and occur up to 30 times an hour. After a pause, normal breathing may resume with a loud snort or choking sound. Sufferers often snore loudly. A University of Wisconsin study published this month shows that over an 18-year period, people with severe, untreated sleep apnea died at a rate more than three times that of those without apnea.

2. Risk factors: These include being male, overweight and older than 40, although sleep apnea can strike anyone at any age, even children. Smokers and those with hypertension are also at risk.

3. Consequences: Sleep apnea can result in severe daytime drowsiness, fatigue and irritability. It may also be responsible for automobile crashes and job impairment.

4. Treatments: A CPAP machine delivers air pressure through a mask placed over your nose while you sleep to keep your upper airway passages open. Oral appliances can also keep your airway passages open. Surgery may be necessary to remove excess tissue from your throat. Losing weight would be helpful.