Obstructive sleep apnea is a disorder in which complete or partial obstruction of the airway during sleep causes loud snoring, oxyhemoglobin desaturations and frequent arousals. As a result, affected persons have unrestful sleep and excessive daytime sleepiness. The disorder is associated with hypertension,1 impotence and emotional problems.2 Because obstructive sleep apnea often occurs in obese persons with comorbid conditions, its individual contribution to health problems is difficult to discern. The disorder has, however, been linked to angina,3 nocturnal cardiac arrhythmias,4 myocardial infarction,5 stroke6 and motor vehicle crashes.7