†These authors contributed equally.
Academic Editor: Luigi De Gennaro
Background: Sleep disturbance is common in the elderly. The effect of sleep duration on cognitive function in the non-demented older adults with high school or above education needs to be clarified. Here, we conducted a cross-sectional study to explore the correlation between sleep duration and multi-domain cognitive function in non-demented older adults. Methods: A total of 226 adults aged 60 years and over who have an educational background over 9 years, received a battery of neuropsychological evaluations. The Mini-Mental State Examination (MMSE) was used to assess global cognitive function, the Auditory Verbal Learning Test (AVLT), Verbal Fluent Test (VFT), Trial Making Test-A/B (TMT-A/B), Symbol Digit Modalities Test (SDMT), and Rey-Osterriech Complex Figure Test (CFT) were used to assess the memory, language, attention and executive, and visuospatial functions respectively. Sleep characteristics were collected by questionnaire. Results: Subjects with sleep disturbance performed worse in visuospatial ability as compared with those with normal sleep. A significant correlation between nocturnal/total sleep duration and MMSE scores and CFT scores was found in overall subjects using linear regression models after adjusting for age, gender, education and BMI. Consistently, the nocturnal/total sleep duration positively correlated with MMSE scores after controlling for age, gender, education, BMI, hypertension, diabetes, hyperlipidemia, coronary artery disease and household conditions. Conclusions: The results indicate that shorter sleep duration impairs the global cognition and visuospatial ability in the older adults with high school or above education, even in the very early non-demented stage.