title: Excessive daytime sleepiness is related to subjective memory impairment in late life: a cross-sectional community-based study.
abstract: OBJECTIVE
  The aim of this study was to determine whether daytime sleepiness is related to subjective memory impairment among community-dwelling elderly people, after adjustment for psychosocial variables.
  
  
  METHODS
  Questionnaires were mailed to all 5199 elderly residents living in one area of Tokyo. The questionnaires collected information about sociodemographic variables, subjective memory impairment, and excessive daytime sleepiness, which was measured by the Japanese version of the Epworth Sleepiness Scale. Information was also collected on sleep hygiene, health-related variables, and psychosocial variables, including perceived social support, social withdrawal, and work status.
  
  
  RESULTS
  Of the 4783 questionnaires that were returned (92.0%), 4185 participants were included in the analysis (valid response rate: 80.5%), after the exclusion of questionnaires with missing data. The average score on the Japanese version of the Epworth Sleepiness Scale was 5.0 ± 3.9 for men and 4.5 ± 3.7 for women. The frequency of excessive daytime sleepiness was 8.3% for men, 5.8% for women, and 7.0% in total. Stepwise multivariate logistic regression revealed the odds ratio of excessive daytime sleepiness as a predictor of subjective memory impairment was 6.06 (95% confidence interval; 3.06-12.03).
  
  
  CONCLUSIONS
  Elderly people who complain of daytime sleepiness are potential candidates for interventions related to dementia care after careful consideration of other possible causes of sleepiness.
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.|Department of Neuropsychiatry, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Okamura
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Ura
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.|Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama, Japan.
authors.forename: Fumiko
authors.initials: F
authors.lastname: Miyamae
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.|Department of Neuropsychiatry, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Sugiyama
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.|Department of Neuropsychiatry, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Niikawa
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.|Department of Geriatrics and Vascular Medicine, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Kae
authors.initials: K
authors.lastname: Ito
authors.affiliation: Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Awata
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D015577:Geriatric Assessment / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D057187:Independent Living; D016015:Logistic Models; D008297:Male; D008569:Memory Disorders / Q000150:complications* / Q000453:epidemiology / Q000523:psychology; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D016017:Odds Ratio; D015995:Prevalence; D011795:Surveys and Questionnaires; D014041:Tokyo / Q000453:epidemiology
keywords: community-dwelling elderly people; daytime sleepiness; dementia; psychosocial variables; subjective memory impairment