title: Hypocretin-1 Levels Associate with Fragmented Sleep in Patients with Narcolepsy Type 1.
abstract: We aimed to analyze nocturnal sleep characteristics of patients with narcolepsy type 1 (narcolepsy with cataplexy) measured by actigraphy in respect to cerebrospinal fluid hypocretin-1 levels of the same patients.
  
  
  
  Actigraphy recording of 1-2 w and hypocretin-1 concentration analysis were done to thirty-six unmedicated patients, aged 7 to 63 y, 50% female. Twenty-six of them had hypocretin-1 levels under 30 pg/mL and the rest had levels of 31-79 pg/mL.
  
  
  
  According to actigraphy, patients with very low hypocretin levels had statistically significantly longer sleep latency (P = 0.033) and more fragmented sleep, indicated by both the number of immobile phases of 1 min (P = 0.020) and movement + fragmentation index (P = 0.049). There were no statistically significant differences in the actual sleep time or circadian rhythm parameters measured by actigraphy.
  
  
  
  Actigraphy gives additional information about the stabilization of sleep in patients with narcolepsy type 1. Very low hypocretin levels associate with more wake intruding into sleep.
authors: Department of Clinical Neurophysiology, HUS Medical Imaging Center, Helsinki University Central Hospital, Finland.|Department of Neurological Sciences, University of Helsinki, Helsinki, Finland.|Helsinki Sleep Clinic, Vitalmed Research Centre, Helsinki, Finland.
authors: Anniina
authors: A
authors: Alakuijala
authors: Department of Neurological Sciences, University of Helsinki, Helsinki, Finland.|Helsinki Sleep Clinic, Vitalmed Research Centre, Helsinki, Finland.|Department of Neurology, The Central Finland Central Hospital, Jyväskylä, Finland.
authors: Tomi
authors: T
authors: Sarkanen
authors: Department of Neurological Sciences, University of Helsinki, Helsinki, Finland.|Helsinki Sleep Clinic, Vitalmed Research Centre, Helsinki, Finland.
authors: Markku
authors: M
authors: Partinen
mesh_terms: D056044:Actigraphy; D000293:Adolescent; D000328:Adult; D002385:Cataplexy / Q000150:complications; D002648:Child; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009290:Narcolepsy / Q000134:cerebrospinal fluid / Q000150:complications*; D000068797:Orexins / Q000134:cerebrospinal fluid*; D012890:Sleep; D012892:Sleep Deprivation / Q000134:cerebrospinal fluid* / Q000150:complications*; D013997:Time Factors; D014851:Wakefulness; D055815:Young Adult
chemical_list: D000068797:Orexins
keywords: actigraphy; disrupted sleep; hypocretin; narcolepsy; sleep fragmentation