title: Relation between self-reported sleep duration and arterial stiffness: a cross-sectional study of middle-aged Japanese civil servants.
abstract: OBJECTIVE
  The aim of this study is to examine the relationship between self-reported sleep duration and arterial stiffness in a large-scale Japanese study.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Sapporo City, Hokkaido, Japan.
  
  
  METHODS
  Local government employees aged 35-62 years, who underwent annual health checkups from April 2003 to March 2004. After excluding those with incomplete data, data from 4,268 employees (males: 3,410) participants were analyzed.
  
  
  METHODS
  N/A.
  
  
  RESULTS
  Brachial-ankle pulse-wave velocity (baPWV) was investigated as an indicator of arterial stiffness. We used a self-administered questionnaire, which included items on daily sleep duration, lifestyle factors, and occupational factors. Sleep duration was classified into 5 categories; " ≤ 5 h," "6 h," "7 h," "8 h," and " ≥ 9 h." Results of multiple linear regression analysis after fully adjusting the model revealed that subjects with ≥ 9 h of daily sleep had significantly elevated baPWV values compared with the reference group with 7 h of sleep. Stratified analyses by sex showed that there was a significant association among male subjects only.
  
  
  CONCLUSIONS
  Daily sleep duration ≥ 9 h was found to be associated with elevated values of baPWV. This suggests that there is an association between long sleep duration and arterial stiffness.
authors: Department of Public Heath Sciences, Hokkaido University Graduate School of Medicine, Sapporo, Japan. e-yoshi@med.hokudai.ac.jp
authors: Eiji
authors: E
authors: Yoshioka
authors: Yasuaki
authors: Y
authors: Saijo
authors: Toshiko
authors: T
authors: Kita
authors: Eisaku
authors: E
authors: Okada
authors: Hiroki
authors: H
authors: Satoh
authors: Mariko
authors: M
authors: Kawaharada
authors: Reiko
authors: R
authors: Kishi
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000209:etiology / Q000503:physiopathology; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007564:Japan; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010991:Plethysmography; D012737:Sex Factors; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000150:complications / Q000503:physiopathology; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires; D013997:Time Factors; D059289:Vascular Stiffness / Q000502:physiology