title: [Effects of sleep stage on blood pressure and heart rate in patients with obstructive sleep apnea syndrome].
abstract: OBJECTIVE
  To determine the effects of sleep stage on blood pressure(BP) and heart rate(HR) and to explore the relationship between BP and HR in patients with obstructive sleep apnea syndrome (OSAS).
  
  
  METHODS
  Manometric tube was retained in the radial artery, and whole-night polysomnography (PSG) was done synchronously in 13 patients with OSAS.
  
  
  RESULTS
  (1) The increase in BP during apnea was higher in REM sleep than in NREM sleep, but the difference was not significant (P > 0.05). When BP in awake state was regared as baseline, the increases in SBP pre-apnea and post-apnea and the increases in DBP post-apnea were significantly higher in REM sleep(-1.9 +/- 11.9 mm Hg, 32.6 +/- 20.6 mm Hg, 18.2 +/- 11.6 mm Hg, respectively) than in NREM sleep (-8.4 +/- 8.0 mm Hg, 20.4 +/- 6.9 mm Hg, 13.2 +/- 5.8 mm Hg, P < 0.05, respectively). (2) In different sleep stages, HR was markedly higher at the end of apnea than before apnea(NREM: 76 +/- 8 bpm vs 70 +/- 8 bpm, P < 0.05; REM: 85 +/- 11 bpm vs 71 +/- 8 bpm, P < 0.01). HR in post-apnea (P < 0.01) and the increase in HR during apnea (NREM: 6.9 +/- 2.2 bpm, REM: 14.1 +/- 10.1 bpm, P < 0.05) were remarkably higher in REM sleep than in NREM sleep, but not for pre-apneic HR. (3) In NREM sleep, HR in pre-apnea was significantly correlated with the increase in SBP and DBP during apnea(r = -0.699, P < 0.01; r = -0.602, P < 0.05, respectively); The increase in SBP during apnea in NREM sleep was also correlated with post-apnea HR (r = -0.669, P < 0.01).
  
  
  CONCLUSIONS
  Sleep stage has effects on BP and HR and the changes in BP are correlated with the changes in HR during apnea in patients with OSAS.
authors.affiliation: Institute of Respiratory Disease, China Medical University, Shenyang, 110001.
authors.forename: D
authors.initials: D
authors.lastname: Xiao
authors.forename: J
authors.initials: J
authors.lastname: Kang
authors.forename: X
authors.initials: X
authors.lastname: Hu
mesh_terms: D000328:Adult; D001794:Blood Pressure; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*; D012894:Sleep Stages / Q000502:physiology*