title: Effect of delayed sleep phase during university life on the daytime functioning in work life after graduation.
abstract: OBJECTIVE
  To examine the effects of changes in sleep phase on the daytime functioning of new university graduates.
  
  
  METHODS
  Questionnaire data of university students (n = 745) and university graduates working full time (n = 360) were analyzed to explore sleep phase changes during this life stage. The newly graduated full-time workers (n = 117) were divided into 2 (bedtime at investigation: earlier/later) × 2 groups (bedtime at one year prior to investigation: earlier/later), and depressive symptoms and health-related quality of life were compared among groups.
  
  
  RESULTS
  New university graduates experienced ~1 h of sleep phase advancement and shortened time in bed compared to one year before investigation. In addition, those who experienced such sleep changes showed larger daytime dysfunction.
  
  
  CONCLUSIONS
  Prevention of extreme sleep phase delay during university days might be helpful for students' adaptation to work environment after graduation.
authors.affiliation: Department of Psychology and Humanities, Edogawa University, Nagareyama, Chiba, Japan; Sleep Research Institute, Edogawa University, Nagareyama, Chiba, Japan. Electronic address: asaoka@gmail.com.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Asaoka
authors.affiliation: Department of Somnology, Tokyo Medical University, Shinjuku, Tokyo, Japan; Japan Somnology Center, Neuropsychiatric Research Institute, Shibuya, Tokyo, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Komada
authors.affiliation: School of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Aritake
authors.affiliation: Department of Somnology, Tokyo Medical University, Shinjuku, Tokyo, Japan; Japan Somnology Center, Neuropsychiatric Research Institute, Shibuya, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Morita
authors.affiliation: Department of Psychology and Humanities, Edogawa University, Nagareyama, Chiba, Japan; Sleep Research Institute, Edogawa University, Nagareyama, Chiba, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Fukuda
authors.affiliation: Department of Somnology, Tokyo Medical University, Shinjuku, Tokyo, Japan; Japan Somnology Center, Neuropsychiatric Research Institute, Shibuya, Tokyo, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Inoue
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000175:diagnosis / Q000523:psychology; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis* / Q000523:psychology; D004650:Employee Performance Appraisal; D005260:Female; D006306:Health Surveys; D006801:Humans; D007564:Japan; D008137:Longitudinal Studies; D008297:Male; D011788:Quality of Life / Q000523:psychology; D012307:Risk Factors; D012892:Sleep Deprivation / Q000175:diagnosis / Q000523:psychology; D020178:Sleep Disorders, Circadian Rhythm / Q000175:diagnosis* / Q000523:psychology; D013334:Students; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Delayed sleep phase; Depressive symptom; Full-time workers; New university graduate; Quality of life; University students