title: Morning-evening preference: sleep pattern spectrum and lifestyle habits among Japanese junior high school pupils.
abstract: We surveyed the sleep-wake patterns and lifestyle habits in a sample of Japanese first to third year junior high school children (n=638, age 12 to 15 yrs), of whom 29.3% were evening type, 64.1% intermediate type, and 6.6% morning type in preference. The morningness-eveningness (M-E) score was lower (more evening typed), 16.1 vs. 15.4 in first compared to third year students. There were significant gender differences, with girls showing a greater evening preference. Evening preference was associated with longer sleep latency, shortened sleep duration during schooldays and weekends, bad morning feeling, and episodes of daytime sleepiness. In contrast, morning preference was associated with higher sleep drive and better sleep-wake parameters and lifestyle habits. Our results suggest the morning preference should be promoted among junior high school children to increase the likelihood of more regular sleep-wake patterns and lifestyle habits.
authors.affiliation: Department of Welfare Promotion and Epidemiology, University of Toyama, Toyama, Japan. alga@med.u-toyama.ac.jp
authors.forename: Alexandru
authors.initials: A
authors.lastname: Gaina
authors.forename: Michikazu
authors.initials: M
authors.lastname: Sekine
authors.forename: Hitomi
authors.initials: H
authors.lastname: Kanayama
authors.forename: Yamagami
authors.initials: Y
authors.lastname: Takashi
authors.forename: Lizhen
authors.initials: L
authors.lastname: Hu
authors.forename: Kayo
authors.initials: K
authors.lastname: Sengoku
authors.forename: Sadanobu
authors.initials: S
authors.lastname: Kagamimori
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D006801:Humans; D007564:Japan; D008019:Life Style; D016015:Logistic Models; D008297:Male; D012727:Sex Characteristics; D012890:Sleep / Q000502:physiology*; D012893:Sleep Wake Disorders / Q000503:physiopathology / Q000517:prevention & control; D013334:Students; D011795:Surveys and Questionnaires