What Is Sleep Apnea?

The most undiagnosed sleep disorder in the country may also be the most dangerous: Obstructive sleep apnea, a condition that robs more than 20 million Americans of rest every night.

The word apnea is Greek for "without breath." And it's as scary as it sounds—both at night, while struggling for air in bed, and during the day, when you're exhausted and driving behind the wheel.

Because its main symptoms—snoring and daytime sleepiness—are often unrecognized or overlooked, people can suffer for years with sleep apnea.

What happens is that the upper airway relaxes during sleep and can interfere with the ability to breathe. People with sleep apnea tend to snore (often loudly) and occasionally snort and gasp for breath when their airway is totally blocked.

This can happen dozens, even hundreds of times a night, without the individual ever being aware that it's happening. The only other signs may be daytime sleepiness and fatigue.

But the condition should be treated. Sleep apnea is linked to a higher risk of hypertension and heart disease.

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