title: Normal cerebrospinal fluid histamine and tele-methylhistamine levels in hypersomnia conditions.
abstract: OBJECTIVE
  To determine the activity of cerebral histaminergic system evaluated by CSF levels of histamine (HA) and tele-methylhistamine (t-MHA), its major metabolite, and their relationships with hypocretin-1 levels in a large population of patients with hypersomnia and neurological conditions.
  
  
  METHODS
  sensitive liquid chromatographic-electrospray/tandem mass spectrometric assay was developed for the simultaneous quantification of CSF HA and t-MHA.
  
  
  METHODS
  ata were collected and CSF hypocretin-1 levels were measured using radioimmunoassay at the Sleep Disorders Center, Montpellier, France. CSF HA and t-MHA were measured in Bioprojet-Biotech, France
  
  
  METHODS
  One hundred fourteen unrelated patients with a suspicion of central hypersomnia underwent one night of polysomnography followed by the multiple sleep latency test. Sleep disorders were diagnosed clinically and using sleep studies: narcolepsy-cataplexy NC (n = 56), narcolepsy without cataplexy NwC (n = 27), idiopathic hypersomnia IH (n = 11), secondary narcolepsy (n = 3), and unspecified hypersomnia Uns EDS (n = 17). Fifty neurological patients without daytime sleepiness were included as controls.
  
  
  RESULTS
  No between-hypersomnia group differences were found for CSF HA levels (median 708.62 pM extreme range [55.92-3335.50] in NC; 781.34 [174.08-4391.50] in NwC; 489.42 [177.45-906.70] in IH, and 1155.40 [134.80-2736.59] in Uns EDS) or for t-MHA levels. No association was found between CSF HA, t-MHA, or HA + t-MHA, sleepiness, treatment intake, and frequency of cataplexy. A slight negative correlation was found between age and HA levels. Further adjustment for the age revealed no significant HA levels difference between hypersomnia patients and controls.
  
  
  CONCLUSIONS
  CSF histamine and tele-methylhistamine did not significantly differ between patients with narcolepsy-cataplexy and other etiologies of non-hypocretin-1 deficient central hypersomnias; these measurements, therefore, are not useful in assessing the etiology or severity of centrally mediated hypersomnia.
authors.affiliation: Sleep Unit, Department of Neurology, Gui de Chauliac Hospital, CHU Montpellier, National Reference Network for Orphan Diseases-Narcolepsy, Hypersomnia, Kleine-Levin Syndrome, France. ydauvilliers@yahoo.fr
authors.forename: Yves
authors.initials: Y
authors.lastname: Dauvilliers
authors.forename: Nathalie
authors.initials: N
authors.lastname: Delallée
authors.forename: Isabelle
authors.initials: I
authors.lastname: Jaussent
authors.forename: Sabine
authors.initials: S
authors.lastname: Scholz
authors.forename: Sophie
authors.initials: S
authors.lastname: Bayard
authors.forename: Mickael
authors.initials: M
authors.lastname: Croyal
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Schwartz
authors.forename: Philippe
authors.initials: P
authors.lastname: Robert
mesh_terms: D000328:Adult; D006970:Disorders of Excessive Somnolence / Q000134:cerebrospinal fluid* / Q000503:physiopathology; D005260:Female; D006632:Histamine / Q000134:cerebrospinal fluid* / Q000502:physiology; D006801:Humans; D008297:Male; D008761:Methylhistamines / Q000134:cerebrospinal fluid* / Q000502:physiology; D008875:Middle Aged; D009290:Narcolepsy / Q000134:cerebrospinal fluid / Q000503:physiopathology; D017286:Polysomnography; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D008761:Methylhistamines; D006632:Histamine; C020404:tele-methylhistamine