Mediating role of depressive symptoms on the relationship between sleep duration and cognitive function

Abstract

Although some studies have shown the association between sleep duration and cognitive impairment is positive, the mechanism explaining how sleep duration is linked to cognition remains poor understood. The current study aims to explore it among Chinese population. A cross-sectional study of 12,589 participants aged 45 or over was conducted, cognition was assessed by three measures to capture mental intactness, episodic memory, and visuospatial abilities. The Center for Epidemiologic Studies Depression Scale 10 (CES-D10) was administered during the face-to-face survey to assess depressive status. Sleep duration was reported by the participants themselves. Partial correlation and linear regression were used to explore the association between sleep duration, cognition, and depression. The Bootstrap methods PROCESS program was used to detect the mediation effect of depression. Sleep duration was positively correlated with cognition and negatively with depression (p < 0.01). The CES-D10 score (r = − 0.13, p < 0.01) was negatively correlated with cognitive function. Linear regression analysis showed sleep duration was positively associated with cognition (p = 0.001). When depressive symptoms were considered, the association between sleep duration and cognition lost significance (p = 0.468). Depressive symptoms have mediated the relationship between sleep duration and cognitive function. The findings revealed that the relationship between sleep duration and cognition is mainly explained by depressive symptoms and may provide new ideas for interventions for cognitive dysfunction.

Sleep duration and cognitive function among rural older adults in China: a population- based study

“…For example, insu cient nighttime sleep duration has been associated with higher burden in global Aβ, medial orbitofrontal Aβ and anterior cingulate Aβ before cognitive change [9]. Besides, middle-aged and older people with short and long sleep durations were reported to have more depressive symptoms, metabolic syndrome and cerebral small vessel disease, which have been found to be associated with an increased risk for cognitive impairment [32][33][34]. Moreover, in rural areas, the old population had the lowest educational level, higher prevalence rate of metabolic syndrome, higher proportion of alcohol consumption, smoking consumption and lower proportion of sh consumption [35,36].…”