title: Combined association of clinical and lifestyle factors with non-restorative sleep: The Nagahama Study.
abstract: BACKGROUND
  Non-restorative sleep (NRS) was suggested to be associated with cardiovascular outcomes. However, causative factors for NRS have not been fully elucidated. This study aimed to clarify factors and their relationships with NRS to better understand the clinical and epidemiological implications of NRS and to develop a score that can objectively evaluate NRS status.
  
  
  METHODS
  Study subjects consisted of 9,788 community residents (age 53.6 ± 13.4 y). Subjective NRS as well as possible clinical and lifestyle factors for NRS were investigated by questionnaires. Other clinical parameters were obtained from personal records of information obtained at the baseline examination.
  
  
  RESULTS
  A total of 3,261 participants complained of NRS. Factors independently associated with subjective NRS were younger age (odds ratio = 1.43), use of a hypnotic drug (2.04), irregular sleep schedule (2.02), short sleep duration (<5 h, 11.7; 5-6 h, 4.81; 6-7 h, 2.40), frequent sleepiness (2.33), routine stress (4.63), no habitual exercise (1.61), nocturia symptoms (1.43), symptoms of gastroesophageal reflux disease (1.44), and depression (1.46) (all P <0.001). The NRS score comprised of these 10 factors was linearly associated with the frequency of subjective NRS (Ptrend <0.001). Frequency of individuals with a high NRS score was greater in women (52.3%) than in men (42.1%, P<0.001), while no clear association was observed with common risk factors for cardiovascular diseases.
  
  
  CONCLUSIONS
  NRS was a phenomenon representing various clinical and lifestyle features. Careful attention should be paid to individuals with a high NRS score who might be at risk for mental fatigue and have unfavorable lifestyle factors.
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Tabara
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Murase
authors.affiliation: Department of Health Informatics, School of Public Health, Kyoto University, Kyoto, Japan.
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Setoh
authors.affiliation: Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Kawaguchi
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Muro
authors.affiliation: Department of Sleep and Behavioral Sciences, Shiga University of Medical Science, Shiga, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kadotani
authors.affiliation: Department of Medical Ethics and Medical Genetics, School of Public Health, Kyoto University, Kyoto, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Kosugi
authors.affiliation: Center for Preventive Medical Science, Chiba University, Chiba, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Sekine
authors.affiliation: Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Yamada
authors.affiliation: Department of Health Informatics, School of Public Health, Kyoto University, Kyoto, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Michiaki
authors.initials: M
authors.lastname: Mishima
authors.affiliation: Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Matsuda
authors.affiliation: Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chin
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D012894:Sleep Stages; D012893:Sleep Wake Disorders / Q000453:epidemiology* / Q000503:physiopathology*; D011795:Surveys and Questionnaires