title: Gender-specific impacts of apnea, age, and BMI on parasympathetic nerve dysfunction during sleep in patients with obstructive sleep apnea.
abstract: BACKGROUND
  The gender-specific influences of various confounding factors, including apnea, age, BMI, and cigarette consumption, on the function of the parasympathetic nerve system (PNS) during sleep in OSA patients has never been investigated.
  
  
  METHODS
  One hundred ninety-seven males and 63 females with OSA were subjected to full PSG examinations including assessment of R-R intervals (RRIs) during an overnight ECG. The PNS-derived modulatory effect on the RRIs and the variability of this effect were quantified during REM and NREM using instantaneous time-frequency analysis with complex demodulation. The spectral domain with the maximum instantaneous amplitude in the high-frequency band between 0.15 and 0.4 Hz was defined as the main HF peak and used as a surrogate marker of PNS discharge. Based on density-spectrum-array maps of the main HF peaks (HF-DSA map), shifts in the central frequency of the main HF peak over time were continuously observed. When the main HF peaks on the HF-DSA maps maintained the same central frequency for more than 20 sec or 5 min, the PNS functions were considered to be "stable" or "very stable", respectively.
  
  
  RESULTS
  Apneas enhanced PNS-derived cardiac-modulation during REM in males, but more importantly, they made PNS-function unstable during both REM and NREM in males and during NREM in females. Aging blunted the PNS-derived cardiac-modulation during both REM and NREM regardless of gender, but aging had no impact on the stability of PNS-function. BMI blunted PNS-eliciting cardiac-modulation during REM in males and during NREM in both males and females. BMI made the PNS unstable during REM in females. Neither height nor cigarette consumption influenced any PNS-related parameter.
  
  
  CONCLUSIONS
  The PNS-derived cardiac-modulation was generally inhibited by aging and obesity, in which the effect of obesity was gender-specific. The PNS instability at nighttime was mainly induced by apneas but by obesity particularly during REM in females.
authors.affiliation: Comprehensive Medical Center of Sleep Disorders, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamaguchi
authors.affiliation: Comprehensive Medical Center of Sleep Disorders, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Inoue
authors.affiliation: NoruPro Light Systems Incorporation, Kokubunji-shi, Tokyo, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Ohki
authors.affiliation: Comprehensive Medical Center of Sleep Disorders, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Satoya
authors.affiliation: Comprehensive Medical Center of Sleep Disorders, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Fukumi
authors.initials: F
authors.lastname: Inoue
authors.affiliation: Department of Urology, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Maeda
authors.affiliation: Department of Cardiology, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Sekiguchi
authors.affiliation: Comprehensive Medical Center of Sleep Disorders, Aoyama Hospital, Tokyo Women's Medical University, Minato-ku, Tokyo, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, Inashiki, Ibaraki, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Tsuji
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, Inashiki, Ibaraki, Japan.
authors.forename: Kazutetsu
authors.initials: K
authors.lastname: Aoshiba
authors.affiliation: The First Department of Medicine, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nagai
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001342:Autonomic Nervous System Diseases / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics; D012737:Sex Factors; D020181:Sleep Apnea, Obstructive / Q000473:pathology / Q000503:physiopathology*; D012895:Sleep, REM; D012907:Smoking / Q000009:adverse effects