title: Comparison of clinical features and polysomnographic findings between men and women with sleep apnea.
abstract: BACKGROUND
  There is a scarcity of reports comparing gender differences in polysomnographic findings among Asian patients with sleep apnea (SA). In this study, we elucidated gender differences in the clinical features and polysomnographic findings of SA patients in Japan.
  
  
  METHODS
  We conducted a case-matched control study to compare the gender differences. A total of 4,714 patients (4,127 men; 587 women) were matched for age, apnea-hypopnea index (AHI), and body mass index (BMI). The criteria used for sex matching were (I) age ±4 years, (II) AHI ± 4 h of sleep, and (III) BMI ±2 kg/m(2). This facilitated the comparison of polysomnography sleep variables in 296 men and 296 women with SA.
  
  
  RESULTS
  Compared with their male counterparts, female SA patients had a significantly higher rapid eye movement AHI [men: 27.7 (IQR, 14.3-45.2); women: 43.3 (IQR, 25.5-56.6); P<0.001], lower supine AHI [men: 29.7 (IQR, 16.8-49.5); women: 25.0 (IQR, 14.7-39.3); P=0.004], longer total sleep time (TST), and non-rapid eye movement (NREM) sleep stage 3 (N3), %TST [TST in men: 356.3 (IQR, 319.5-392.3); women: 372.0 (IQR, 327.8-404.5); P=0.007; N3, %TST in men: 8.8 (IQR, 3.0-14.6); women: 14.4 (IQR, 8.3-20.4); P<0.001], and better sleep efficiency [men: 80.9 (IQR, 71.0-88.0); women: 83.2 (IQR, 74.5-90.0); P=0.011].
  
  
  CONCLUSIONS
  This study revealed that women with SA had a significantly longer TST and N3, %TST, which represents deep sleep. Future prospective studies must be conducted together with polysomnography tests including electromyography of pharyngeal muscle expansion and electroencephalography.
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Shiho
authors.initials: S
authors.lastname: Yamakoshi
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Kasai
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tomita
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Takaya
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kasagi
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Masateru
authors.initials: M
authors.lastname: Kawabata
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Narui
authors.affiliation: 1 Department of Respiratory Medicine, Tokyo Medical University, Tokyo, Japan ; 2 Department of Pulmonary and Critical Care Medicine, Toranomon Hospital Kajigaya, Kanagawa, Japan ; 3 Sleep Center, Toranomon Hospital, Tokyo, Japan ; 4 Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Setoguchi
keywords: Sleep disordered breathing; gender; polysomnography; sleep study