title: Sleep duration and the risk of breast cancer: the Ohsaki Cohort Study.
abstract: In a prospective study of 23 995 Japanese women, short sleep duration was associated with higher risk of breast cancer (143 cases), compared with women who slept 7 h per day, the multivariate hazard ratio of those who slept </=6 h per day was 1.62 (95% confidence interval: 1.05-2.50; P for trend=0.03).
authors.affiliation: Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kakizaki
authors.forename: S
authors.initials: S
authors.lastname: Kuriyama
authors.forename: T
authors.initials: T
authors.lastname: Sone
authors.forename: K
authors.initials: K
authors.lastname: Ohmori-Matsuda
authors.forename: A
authors.initials: A
authors.lastname: Hozawa
authors.forename: N
authors.initials: N
authors.lastname: Nakaya
authors.forename: S
authors.initials: S
authors.lastname: Fukudo
authors.forename: I
authors.initials: I
authors.lastname: Tsuji
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008550:Melatonin / Q000502:physiology; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012306:Risk; D012890:Sleep; D013997:Time Factors
chemical_list: D008550:Melatonin