Sleep patterns and long-term mortality among older Israeli adults: a population-based study

Area of Science:

• Gerontology
• Sleep Medicine
• Public Health

Background:

• The combined impact of night sleep duration and daytime napping (siesta) on mortality in older adults is not well understood.
• Previous research has not fully explored how cognitive function might modify this relationship.

Purpose of the Study:

• To investigate the association between different sleep patterns (night sleep duration and siesta) and long-term mortality in older adults.
• To determine if cognitive status modifies the relationship between sleep patterns and mortality.

Main Methods:

• Analysis of data from 1519 older adults (aged 65+) from the National Health and Nutrition Survey ('Mabat Zahav').
• Assessment of night sleep duration, siesta habits, and cognitive status using questionnaires and the Mini-Mental State Examination.
• Cox proportional hazards models and spline regression were used to analyze mortality data (782 deaths) in relation to sleep patterns and cognitive function.

Main Results:

• Participants with long night sleep and siesta had the highest mortality risk (HR 2.07), followed by long night sleep/no siesta (HR 1.63) and short night sleep/siesta (HR 1.43) compared to short night sleep/no siesta.
• Adjusted hazard ratios for mortality ranged from 1.27 to 1.41 after controlling for covariates.
• The association between night sleep duration and mortality was linear in cognitively preserved individuals but U-shaped in those with cognitive impairment.

Conclusions:

• Prolonged night sleep and the practice of siesta are associated with increased mortality risk in older adults.
• Cognitive performance significantly modifies the relationship between sleep patterns and mortality.
• These findings highlight the importance of considering both sleep habits and cognitive status in assessing mortality risk in the elderly.