'Apnea' (AP-nee-uh) comes from the Greek word meaning 'want of breath,' and it refers to an abnormal, temporary stopping of breathing. It's most common form is sleep apnea, a breathing disorder first described in 1965 that's characterized by brief interruptions of breathing during sleep. There are two types of sleep apnea: 'central'-- which is caused by the brain failing to tell the muscles to breathe-- and 'obstructive'-- which occurs when air can't flow in or out of the nose or mouth. People of any age can have apnea. Brief periods of apnea are normal during the sleep of newborns, but babies suspected of being at risk of more serious apnea should be placed on a monitor that senses breathing and heart rate and signals an alarm if these become abnormal. More serious apnea can lead to 'SIDS,' Sudden Infant Death Syndrome. In children, it's most often caused by obesity or by enlarged adenoids or tonsils. Older children and adults with sleep apnea may have neuromuscular problems, such as cerebral palsy or Down's syndrome, or they may be obese. In older children and adults, sleep apnea can interfere with getting a good night's sleep. More severe complications occur when oxygen levels in the lungs and bloodstream fall and carbon dioxide rises, which can cause brain oxygen deprivation, cardiac problems, poor growth, or sudden death. Symptoms of sleep apnea include periods of loud snoring and then silence, sleeping in an abnormal position to allow for better breathing, or even turning blue. Treatment in children includes removing tonsils and adenoids. Adults may further have the uvula (YOU-vyuh-luh) and soft palate tissue removed. Weight loss is recommended for those who are obese.