ABSTRACT
OBJECTIVES: We aimed to compare sleep factors including daytime sleepiness, sleep apnea and insomnia between mild cognitive impairment (MCI) patients and normal control (NC) subjects and to illustrate their relationship with neuropsychological function in the preclinical stage of dementia. METHODS: Epworth Sleepiness Scale (ESS), sleep apnea subscale of Sleep Disorders Questionnaire (SA) and questionnaire on insomnia were administered to community-dwelling elderly subjects above the age of 60. Both clinical and neuropsychological batteries of the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) assessment packet and Stroop Color and Word Test (SCWT) were done for each subject. Seventy seven NC subjects and 47 MCI patients were selected. RESULTS: In the NC group, ESS scores negatively correlated with Stroop interference (SI) scores. SA scores were negatively correlated with Stroop Color Word (SCW) and SI scores. In the MCI group, ESS scores negatively correlated with SCW scores, and SA scores had no correlation with each neurocognitive function test. CONCLUSION: Daytime sleepiness was associated with impaired executive function in community-dwelling normal elderly subjects and MCI patients. But the higher risk of SA was associated with decreased executive function only in normal elderly subjects.