People with Down syndrome are at increased risk of sleep apnea, not only from obstruction of the upper airway, but also of central origin. According to published data, sleep apnea may occur in at least 40% of children and adults with Down syndrome. Consequences of these sleep apnea are numerous : failure to thrive, cognitive decline, high blood pressure, heart disease, accident due to day sleepiness, fatigue. This condition is treatable in people with Down syndrome, as it is in ordinary people.