Clinical study on idiopathic CNS hypersomnolence.

Although idiopathic CNS hypersomnolence is the third most frequent hypersomnia diagnosis, the syndrome is still unfamiliar to physicians, especially in Japan. In the Sleep Disorders Clinic of Kurume University Hospital, seven patients were diagnosed as idiopathic CNS hypersomnolence. All the patients complained of persistent daytime sleepiness, difficulty in morning awakening and lengthening of nocturnal sleep. Their daytime sleepiness had not been reduced even when they have taken sufficient nocturnal sleep. Various autonomic symptoms were observed, but what has noticeably been absent were cataplexy, sleep paralysis, sleep attack, sleep apnea or any other identifiable neurological disorders. The onset of the syndrome in four of the seven patients occurred in their teens. No therapeutic effects had been found after undergoing medical treatments.