ABSTRACT

It has taken a paradigm shift for society to regard sleepiness as a disorder, rather than a moral failing or sin. Patients often take several years to bring a complaint of sleepiness to the attention of a physician, and physicians have generally not been trained to apply a medical model to the problem. Although many diseases causing excessive sleep have probably existed for centuries, sleepiness has become an epidemic in modern times. Since the invention of electric lighting, time spent awake has increased and social and economic pressures have further reduced the time available for sleep. It was estimated in 1975 that Americans were sleeping one and a half hours less than in 1900 (1). At least 20% of American workers do shift work, a clear contributor to hypersomnolence. Obstructive sleep apnea syndrome, the commonest disease causing sleepiness, has increased in frequency as a result of the increasing prevalence of obesity.