Sleep patterns and total mortality: a 12-year follow-up study in Japan.
A population-based cohort study was conducted to assess the relationship between total mortality and self-reported sleep patterns as regards not only to sleep duration but also subjective sleep quality. A total of 5,322 inhabitants in Gifu Prefecture, Japan, completed a self-administered questionnaire on health status and lifestyles including habitual sleep patterns, and were followed-up for an average of 11.9 years. Relative risks were computed by using Cox proportional hazards models. Both longer and shorter sleep, compared to 7-8 hour-sleep, was related to significantly increased risk of total mortality in males (relative risk [RR] for > or = 10 hours = 1.94, and RR for < 7 hour = 1.90), but not in females. Females complaining of poor awakening state experienced a higher mortality risk compared to those who woke up normally (RR: 1.97). Males who usually fell asleep easily showed a marginally lower mortality risk compared to those who fell asleep normally (RR: 0.70). Female users of sleeping pills were at an elevated risk (RR: 1.89). These findings were almost unchanged after adjustment for sleep duration and other confounders. Poor self-reported quality of sleep seemed to be associated with an increased risk of mortality independently of sleep duration.
Kojima
M
M
Department of Preventive Medicine, Nagoya University School of Medicine, Japan.
Wakai
K
K
Kawamura
T
T
Tamakoshi
A
A
Aoki
R
R
Lin
Y
Y
Nakayama
T
T
Horibe
H
H
Aoki
N
N
Ohno
Y
Y
D000328:Adult; D000368:Aged; D001294:Attitude to Health; D016009:Chi-Square Distribution; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007564:Japan / Q000453:epidemiology; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009026:Mortality; D015999:Multivariate Analysis; D011159:Population Surveillance; D016016:Proportional Hazards Models; D012307:Risk Factors; D012737:Sex Factors; D012890:Sleep / Q000502:physiology; D012893:Sleep Wake Disorders / Q000453:epidemiology*; D020922:Sleep-Wake Transition Disorders / Q000453:epidemiology; D013997:Time Factors
D006993:Hypnotics and Sedatives