The present study reports for the first time the occurrence of a severe and peculiar motor disorder during REM sleep in paediatric type 1 narcolepsy and confirms the presence of a severe motor dyscontrol in these patients, emerging not only from wakefulness (i.e. status cataplecticus), but also from sleep (i.e. complex behaviours during REM sleep).
Isolated hypersomnia disorder included narcolepsy in 35% (type 1, n = 1, and type 2, n = 8), hypersomnia in 12% (total sleep time >11 hours, n = 2, and MSLT <8 minutes, n = 1), and borderline phenotype in 53% (≥2 sleep onset in REM periods and MSLT >8 minutes, n = 10, and 8 minutes < MSLT < 10 minutes, n = 4).
A nocturnal sleep onset REM period (defined as REM onset latency ≤ 15 min; SOREMP) occurs rarely and research has shown that the phenomenon is specific for type 1 and 2 narcolepsy.
Nearly 30% of the relatives fulfilled the criteria of narcolepsy spectrum disorder (shortened mean sleep latency [MSL] and/or the presence of sleep onset REM periods [SOREMPs]).
Narcolepsy is a chronic neurologic disorder characterized by excessive daytime sleepiness and abnormal manifestations of REM sleep including cataplexy, sleep paralysis, and hypnagogic hallucinations.
Furthermore, our results revealed that cataplexy onset corresponds to the emergence of adult-like REM sleep and to previously reported neuroanatomical and neurochemical abnormalities in canine narcolepsy.
Narcolepsy is a genetically determined disorder of sleep characterized by excessive daytime sleepiness and abnormal manifestations of REM sleep that affects both humans and animals.