Cover Story

As many as 18 million Americans have sleep apnea--brief interruptions of breathing during sleep. Four percent of middle-aged men and 2 percent of middle-aged women have sleep apnea along with excessive daytime drowsiness. In a given night, the number of involuntary breathing pauses, called apneic events, may be as high as 20 to 30 or more per hour.

Further Reading

Source: National Center on Sleep Disorders Research, National Institutes of Health