Very late onset narcolepsy type 1: a case report and review of the literature

Narcolepsy type 1 (NT1) is a clinical syndrome defined by recurrent episodes of excessive daytime sleepiness (EDS), episodes of cataplexy, hypnagogic hallucinations, and sleep paralysis. Symptoms typically manifest in the second or third decade with another small peak in the fourth decade. In this report we describe the case of a 64-year-old woman presenting with new-onset visual hallucinations as the main complaint. Eventually diagnosis of NT1 was confirmed by determination of orexin levels (hypocretin-1) on cerebrospinal fluid. This case illustrates that age of onset of NT1 can be as late as the sixth decade in life and that NT1 should be considered as a possible though rare diagnosis in older adults presenting with new onset neuropsychiatric symptoms like visual hallucinations.