title: Presentations of primary hypersomnia in Chinese children.
abstract: OBJECTIVE
  To retrospectively describe childhood presentations of primary hypersomnia with an emphasis on narcolepsy-cataplexy in a Chinese population.
  
  
  METHODS
  A total of 417 children (< 18 years old) successively presenting with complaints of hypersomnia without anatomic cause or sleep apnea risk were evaluated using the Stanford Sleep Inventory, human leukocyte antigen (HLA) DQB1*0602 typing, and MSLT recordings. CSF hypocretin-1 was measured in 47 cases to document hypocretin deficiency. A subgroup ("narcolepsy/hypocretin deficiency") with likely hypocretin deficiency (low hypocretin-1 or HLA positive with clear-cut cataplexy) was further examined for presentations prior to, around, or after puberty.
  
  
  RESULTS
  Narcolepsy with (n = 361) or without (n = 17) cataplexy presented at an earlier age and with increased male predominance when compared to idiopathic hypersomnia (n = 39, P < 0.01). Nearly 70% of those with narcolepsy/hypocretin deficiency (n = 271) had disease onset before age 10 y, and 15% had onset before age 6, an unusually young age distribution. Onset was prior to puberty in 78% of cases. Clinical features were similar in presentations across puberty groups except for sleep paralysis, which increased in frequency with age/puberty. Mean sleep latency (MSL) decreased and the number of sleep onset REM periods (SOREMPs) increased with age/puberty, but MSLT diagnosis criteria (MSL ≤ 8 min, ≥ 2 SOREMPs) were similarly positive across groups. Familial clustering was present in only 1.7% of probands.
  
  
  CONCLUSIONS
  In children presenting with a complaint of primary hypersomnia to a sleep clinic in China, 86% (361/417) meet criteria for narcolepsy with cataplexy. Puberty did not affect positivity on the MSLT as a diagnostic feature. Sleep paralysis was the only symptom that increased with increasing age. In addition, narcolepsy with cataplexy in our clinic population appeared to begin at a younger age than usually reported in other studies.
authors.affiliation: Department of Pulmonary Medicine, Beijing University People’s Hospital, Beijing, China. hanfang1@hotmail.com
authors.forename: Fang
authors.initials: F
authors.lastname: Han
authors.forename: Ling
authors.initials: L
authors.lastname: Lin
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Adi
authors.initials: A
authors.lastname: Aran
authors.forename: Song X
authors.initials: SX
authors.lastname: Dong
authors.forename: Pei
authors.initials: P
authors.lastname: An
authors.forename: Long
authors.initials: L
authors.lastname: Zhao
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Qian Y
authors.initials: QY
authors.lastname: Li
authors.forename: Han
authors.initials: H
authors.lastname: Yan
authors.forename: Jie S
authors.initials: JS
authors.lastname: Wang
authors.forename: Hui Y
authors.initials: HY
authors.lastname: Gao
authors.forename: Mei
authors.initials: M
authors.lastname: Li
authors.forename: Zhan C
authors.initials: ZC
authors.lastname: Gao
authors.forename: Kingman P
authors.initials: KP
authors.lastname: Strohl
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Mignot
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D002648:Child; D002681:China; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000172:deficiency; D008297:Male; D009290:Narcolepsy / Q000175:diagnosis / Q000503:physiopathology; D009479:Neuropeptides / Q000172:deficiency; D000068797:Orexins; D011627:Puberty / Q000502:physiology; D012189:Retrospective Studies; D012890:Sleep / Q000502:physiology
chemical_list: C000596229:HCRT protein, human; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins