Sleep disturbances and risk of frailty and mortality in older men.
OBJECTIVE
To test the hypothesis that non-frail older men with poorer sleep at baseline are at increased risk of frailty and death at follow-up.


METHODS
In this prospective cohort study, subjective (questionnaires) and objective sleep parameters (actigraphy, in-home overnight polysomnography) were measured at baseline in 2505 non-frail men aged ≥67years. Repeat frailty status assessment performed an average of 3.4 years later; vital status assessed every four months. Sleep parameters expressed as dichotomized predictors using clinical cut-points. Status at follow-up exam classified as robust, intermediate (pre-frail) stage, frail, or died in interim.


RESULTS
None of the sleep disturbances were associated with the odds of being intermediate/frail/dead (vs. robust) at follow-up. Poor subjective sleep quality (multivariable odds ratio [MOR] 1.26, 95% CI 1.01-1.58), greater nighttime wakefulness (MOR 1.31, 95% CI 1.04-1.66), and greater nocturnal hypoxemia (MOR 1.47, 95% CI 1.02-2.10) were associated with a higher odds of frailty/death at follow-up (vs. robust/intermediate). Excessive daytime sleepiness (MOR 1.60, 95% CI 1.03-2.47), greater nighttime wakefulness (MOR 1.57, 95% CI 1.12-2.20), severe sleep apnea (MOR 1.74, 95% CI 1.04-2.89), and nocturnal hypoxemia (MOR 2.28, 95% CI 1.45-3.58) were associated with higher odds of death (vs. robust/intermediate/frail at follow-up). The association between poor sleep efficiency and mortality nearly reached significance (MOR 1.48, 95% CI 0.99-2.22). Short sleep duration and prolonged sleep latency were not associated with frailty/death or death at follow-up.


CONCLUSIONS
Among non-frail older men, poor subjective sleep quality, greater nighttime wakefulness, and greater nocturnal hypoxemia were independently associated with higher odds of frailty or death at follow-up, while excessive daytime sleepiness, greater nighttime wakefulness, severe sleep apnea and greater nocturnal hypoxemia were independently associated with an increased risk of mortality.
Center for Chronic Disease Outcomes Research, Veterans Affairs Health Care System, Minneapolis, MN, USA. ensru001@umn.edu
Kristine E
KE
Ensrud
Terri L
TL
Blackwell
Sonia
S
Ancoli-Israel
Susan
S
Redline
Peggy M
PM
Cawthon
Misti L
ML
Paudel
Thuy-Tien L
TT
Dam
Katie L
KL
Stone
D056044:Actigraphy; D000368:Aged; D006970:Disorders of Excessive Somnolence / Q000150:complications / Q000401:mortality; D016330:Frail Elderly / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D017286:Polysomnography; D011446:Prospective Studies; D012307:Risk Factors; D012891:Sleep Apnea Syndromes / Q000150:complications / Q000401:mortality; D012893:Sleep Wake Disorders / Q000150:complications / Q000401:mortality*