narcolepsy venn diagram of symptoms full

Daytime sleepiness occurs in all people with narcolepsy, but the frequency of other symptoms varies among individuals. This diagram illustrates the occurrence and overlap of major symptoms in one sample of 100 patients with narcolepsy. In this group, 87% had cataplexy, and about half reported hallucinations (hypnagogic or hypnopompic) or sleep paralysis. Only 36% of these individuals had all four symptoms. The frequency of symptoms varies among studies and patient populations; for example, cataplexy occurs in 60–80% of patients with narcolepsy in some other studies.