Sleep apnea

An estimated 18 million Americans have sleep apnea, a serious, potentially life-threatening disorder characterized by episodes of interrupted breathing during sleep.

Obstructive sleep apnea, the more common type, occurs when air cannot flow into or out of the person's airway despite efforts to breathe. It usually is associated with fat buildup or loss of muscle tone with aging, which allow the windpipe to collapse during breathing.

Central sleep apnea occurs when the system that controls breathing is abnormal and there are decreased efforts to breathe during sleep.

In sleep apnea, the brain has to awaken the sufferer in order for breathing to start again. Frequent arousals from apneic events during the night prevent the person from getting enough deep, restorative sleep. Because of the constant interruption of their normal sleep patterns, people with sleep apnea often feel very sleepy, causing problems with daytime concentration and performance. It recently has been shown that sleep apnea contributes to high blood pressure. Risks for heart attack, irregular heartbeat, and stroke also are increased in those with sleep apnea. Other consequences of sleep apnea include depression, irritability, sexual dysfunction, learning and memory difficulties, and falling asleep while at work, on the phone, or driving.

Sleep apnea's association with obesity can create a vicious cycle for some patients, who may find it harder to exercise because of their sleepiness. Successful treatment, usually with nasal continuous positive airway pressure or CPAP, may reduce sleepiness, motivating patients to effectively lose weight and, in turn, help alleviate the breathing obstruction. People with sleep apnea should not take sedatives or sleeping pills, because they may prevent them from awakening to breathe.