title: A preliminary study on the influence of obstructive sleep apnea upon cumulative parasympathetic system activity.
abstract: OBJECTIVE
  Although the autonomic nervous system plays a key role in mediating cardiovascular changes during obstructive sleep apnea (OSA), parasympathetic nervous system (PNS) activity during sleep apnea has not yet been sufficiently investigated. This study is to discuss the relationship between PNS activity and OSA.
  
  
  METHODS
  Polysomnography recording was carried out in 76 patients (71 male and 5 female) with OSA. Cumulative PNS activity during sleep for each patient was derived from time series data of electrocardiogram (ECG) and analyzed by coarse graining spectral analysis of heart rate variability. The correlation between cumulative PNS activity and apnea-hypopnea index (AHI) was then discussed.
  
  
  RESULTS
  Cumulative PNS activity and PNS peaks during sleep were lowly but significantly correlated with OSA severity (r=-0.344, p<0.005; and r=-0.266, p<0.05 respectively), and a linear regression equation could be established. Furthermore, significant correlation was also observed in the adult groups and in the moderate and severe groups, but not in the juvenile and the elderly and mild groups.
  
  
  CONCLUSIONS
  These findings indicated that PNS function was obviously influenced by OSA during sleep. Cumulative PNS activity level might also serve as a useful parameter for the evaluation of OSA.
authors.affiliation: Division of Adult Nursing, Department of Clinical Nursing, Shiga University of Medical Science, Seta, Otsu 520-2192, Japan.
authors.forename: Ryoko
authors.initials: R
authors.lastname: Tabata
authors.forename: Min
authors.initials: M
authors.lastname: Yin
authors.forename: Meiho
authors.initials: M
authors.lastname: Nakayama
authors.forename: Maiko
authors.initials: M
authors.lastname: Ikeda
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hata
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Shibata
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Itasaka
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ishikawa
authors.forename: Masako
authors.initials: M
authors.lastname: Okawa
authors.forename: Soichiro
authors.initials: S
authors.lastname: Miyazaki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010275:Parasympathetic Nervous System / Q000503:physiopathology*; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*