title: [Pilot study on the differences of young male's sleep structure and quality between indigenous Tibetans and longtime Han residents in high altitude area].
abstract: OBJECTIVE
  To compare young males' sleep quality and structure between native Tibetans and longtime Han residents.
  
  
  METHODS
  A total of 14 male Tibetans and 11 male Hans at an altitude of 3 780 m were enrolled in this study. Tibetans were native highlanders with a mean age of (32.0 ± 9.1) years. Han subjects were born and living in high altitude with a mean age of (36.6 ± 7.6) years. All subjects were monitored by Polysomnography(PSG), and the differences of sleep structure and quality between the two groups were compared according to the international standard.
  
  
  RESULTS
  The sleep efficiency (93.1% ± 3.9% vs 85.7% ± 4.2%) and nocturnal oxygen saturation (SpO(2)) (89.4% ± 2.0% vs 84.6% ± 4.3%) in Tibetans was significantly higher than those in Hans (both P<0.05). The number of awakening ((1.9 ± 0.8) vs (4.1 ± 1.3)/h) and micro-awakening ((23.4 ± 5.8) vs (28.7 ± 4.1)/h), the oxygen reduction index ((11.7 ± 4.8) vs (16.3 ± 7.5)/h), apnea hypoventilation index (AHI) ((5.8 ± 2.3) vs (9.6 ± 4.2)/h) and average heart rate ((66.9 ± 8.3) vs (79.9 ± 6.7)/min) of Tibetans were significantly lower than Hans (all P<0.05). Tibetans had longer slow wave sleep (20.1% ± 7.2% vs 8.8% ± 3.3%) and the Hans had longer stage 2 of non-rapid eye movement (NREM) (31.1% ± 11.9% vs 18.4% ± 6.7%) and shallow sleep (76.1 ± 11.7 vs 70.8 ± 11.2) (all P<0.05).
  
  
  CONCLUSIONS
  Tibetans have better sleep quality and higher sleep efficiency than Han residents at high altitude.
authors.affiliation: Department of Respiratory Medicine, Affiliated Hospital of Qinghai University, Xining 810001, China.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Gao
authors.forename: Tana
authors.initials: T
authors.lastname: Wuren
authors.forename: Qin
authors.initials: Q
authors.lastname: Ga
authors.forename: Wei
authors.initials: W
authors.lastname: Guan
authors.affiliation: Research Center for High Altitude Medicine, Qinghai University, Xining 810001, China, Email: geriligao@hotmail.com.
authors.forename: Rili
authors.initials: R
authors.lastname: Ge
mesh_terms: D000328:Adult; D000531:Altitude; D001049:Apnea; D006801:Humans; D000860:Hypoxia; D008297:Male; D010865:Pilot Projects; D017286:Polysomnography; D012890:Sleep