Sleep duration and the risk of breast cancer: the Ohsaki Cohort Study.
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).
Kakizaki
M
M
Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
Kuriyama
S
S
Sone
T
T
Ohmori-Matsuda
K
K
Hozawa
A
A
Nakaya
N
N
Fukudo
S
S
Tsuji
I
I
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
D008550:Melatonin