Sleep patterns and mortality among elderly patients in a geriatric hospital.
BACKGROUND
Sleep disturbance is one of the major and unsolved problems in older people. Most of the previous sleep studies rely on self-reported documents, and memory disturbance in older people might bias sleep complaints and health status.


OBJECTIVE
Sleep disturbances were studied as a mortality risk.


METHODS
In 272 patients who were aged, infirmed and chronically institutionalized in a skilled-care geriatric hospital, the presence or absence of sleep disturbances were examined by hourly observations of patients over 2 weeks at baseline, and they were prospectively followed up for 2 years to assess mortality.


RESULTS
Mortality after 2 years was significantly higher in the nighttime insomnia, daytime sleepiness, and sleep-onset delay groups. Further, adjusted for age, gender and activities of daily living status, the presence of nighttime insomnia and sleep-onset delay remained associated with a higher risk of mortality.


CONCLUSIONS
Sleep disturbance may be one of the symptoms indicating poor health or functional deficits, and be an independent risk factor for survival.
Manabe
K
K
Department of Geriatric and Respiratory Medicine, Tohoku University School of Medicine, Sendai, Japan.
Matsui
T
T
Yamaya
M
M
Sato-Nakagawa
T
T
Okamura
N
N
Arai
H
H
Sasaki
H
H
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D001510:Bed Rest; D005260:Female; D006299:Health Services for the Aged / Q000706:statistics & numerical data*; D017052:Hospital Mortality; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D009735:Nursing Homes / Q000706:statistics & numerical data*; D016016:Proportional Hazards Models; D012307:Risk Factors; D012890:Sleep; D007319:Sleep Initiation and Maintenance Disorders / Q000401:mortality*; D016019:Survival Analysis