Association of Sleep Duration with Cognitive Performance in the Elderly: A Cross-Sectional Study from National Health and Nutrition Examination Survey (NHANES)

Background The incidence of cognitive dysfunction and nervous system diseases is increasing with the aging trend, which has become an essential challenge in the global health field. This study aims to explore the relationship between sleep duration and cognitive performance, paying particular attention to the influence of sleep duration in different populations. Methods The National Health and Nutrition Survey data from 2011 to 2014 were used to evaluate the relationship between sleep duration and cognitive performance. Cognitive performance was assessed by three tests: Alzheimer's Disease Registration Association (CERAD), Animal Fluency (AF), and Digital Symbol Substitution Test (DSST). The weighted multivariate logistic regression model verified the relationship between sleep duration and cognitive performance. A restricted cubic spline model was used to determine the nonlinear relationship between sleep duration and cognitive performance. Results Of a total of 19931 patients, 2582 patients were included. Our study found a significant positive correlation between prolonged sleep (more than 9 hours per night) and cognitive decline (multivariate-adjusted OR = 1.50,95%CI:1.10 ~ 2.05). In contrast, short periods of sleep (less than seven hours per night) showed no significant correlation in cognitive function. Participants who slept moderately (7–9 hours per night) performed better on cognitive tests, with higher CERAD, AFT, and DSST scores. The association findings highlight the possible effects of sleep on cognitive health, especially in older people. Conclusion This study emphasizes that long sleep may be related to the decline of cognitive function in the elderly. Future research should explore the physiological mechanism and potential causes of sleep and cognitive function to support the maintenance of cognitive health in the elderly more scientifically.