Idiopathic hypersomnia is an uncommon syndrome characterized by a complaint of constant or recurrent excessive daytime sleepiness, typically with sleep episodes lasting 1 or more hours in duration. It is enhanced in situations that allow sleepiness to become manifest, such as reading or watching television in the evening. The major sleep episode may be prolonged, lasting more than 8 hours. The capacity to arouse the subject may be normal, but some patients report great difficulty waking up and experience disorientation after awakening.23
Individuals have excessive daytime sleepiness, but do not satisfy the diagnostic criteria for narcolepsy. Specifically, they have short sleep latency, but do not manifest the rapid eye movement (REM) sleep dysregulation seen in narcolepsy. Frequently, the polysomnogram is normal. It should be noted that many individuals in the population at large likely meet the diagnostic criteria of idiopathic hypersomnia. Indeed, the most common causes of both subjective and objective sleepiness are not sleep disorders, but rather sleep deprivation, depression, obesity, mood disturbance and medication side effects.
Treatment of Idiopathic Hypersomnia
Alerting medications such as methylphenidate can be effective in treating idiopathic hypersomnia, with varying degrees of success.
LEO-Specific Clinical Studies and Reports
The excessive sleepiness that may be caused by idiopathic hypersomnia can adversely affect situational awareness, vigilance, executive functioning, and judgement. Therefore, the LEO diagnosed with idiopathic hypersomnia should be evaluated by the police physician, and the ability to perform essential job tasks should be evaluated by supervisors. The LEO with confirmed idiopathic hypersomnia who does not adequately respond to medical management should be subject to appropriate work restrictions.
The police physician should ensure that an appropriate workup has been performed to exclude other causes of sleep disturbances. Because idiopathic hypersomnia is a diagnosis of exclusion, the workup should include an observed polysomnogram.