title: Excessive sleep duration and quality of life.
abstract: OBJECTIVE
  Using population-based data, we document the comorbidities (medical, neurologic, and psychiatric) and consequences for daily functioning of excessive quantity of sleep (EQS), defined as a main sleep period or 24-hour sleep duration ≥ 9 hours accompanied by complaints of impaired functioning or distress due to excessive sleep, and its links to excessive sleepiness.
  
  
  METHODS
  A cross-sectional telephone study using a representative sample of 19,136 noninstitutionalized individuals living in the United States, aged ≥ 18 years (participation rate = 83.2%). The Sleep-EVAL expert system administered questions on life and sleeping habits; health; and sleep, mental, and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision; International Classification of Sleep Disorders: Diagnostic and Coding Manual II, International Classification of Diseases and Related Health Problems, 10th edition).
  
  
  RESULTS
  Sleeping at least 9 hours per 24-hour period was reported by 8.4% (95% confidence interval = 8.0-8.8%) of participants; EQS (prolonged sleep episode with distress/impairment) was observed in 1.6% (1.4-1.8%) of the sample. The likelihood of EQS was 3 to 12× higher among individuals with a mood disorder. EQS individuals were 2 to 4× more likely to report poor quality of life than non-EQS individuals as well as interference with socioprofessional activities and relationships. Although between 33 and 66% of individuals with prolonged sleep perceived it as a major problem, only 6.3 to 27.5% of them reported having sought medical attention.
  
  
  CONCLUSIONS
  EQS is widespread in the general population, co-occurring with a broad spectrum of sleep, medical, neurologic, and psychiatric disorders. Therefore, physicians must recognize EQS as a mixed clinical entity indicating careful assessment and specific treatment planning.
authors.affiliation: Stanford Sleep Epidemiology Research Center, Stanford University School of Medicine, Palo Alto, CA 94303, USA. mohayon@stanford.edu
authors.forename: Maurice M
authors.initials: MM
authors.lastname: Ohayon
authors.forename: Charles F
authors.initials: CF
authors.lastname: Reynolds
authors.forename: Yves
authors.initials: Y
authors.lastname: Dauvilliers
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology*; D008875:Middle Aged; D011159:Population Surveillance / Q000379:methods*; D011788:Quality of Life / Q000523:psychology*; D012890:Sleep / Q000502:physiology; D014481:United States / Q000453:epidemiology; D055815:Young Adult