title: Sleep Perception in Obstructive Sleep Apnea: A Study Using Polysomnography and the Multiple Sleep Latency Test.
abstract: OBJECTIVE
  Discrepancies between objectively measured sleep and subjective sleep perception in patients with insomnia have been reported. However, few studies have investigated sleep-state misperception in patients with obstructive sleep apnea (OSA). We designed this study to 1) delineate the factors that could affect this discrepancy and 2) infer an underlying mechanism in patients with OSA.
  
  
  METHODS
  We recruited patients who visited our sleep clinic for the evaluation of their snoring and/or observed OSA. Participants completed a structured questionnaire and underwent overnight polysomnography. On the following day, five sessions of the multiple sleep latency test (MSLT) were applied. We divided the patients into two groups: normal sleep perception and abnormal perception. The abnormal-perception group included patients whose perceived total sleep time was less than 80% of that measured in polysomnography.
  
  
  RESULTS
  Fifty OSA patients were enrolled from a university hospital sleep clinic. Excessive daytime sleepiness, periodic limb movement index (PLMI), and the presence of dreaming were positively associated with poor sleep perception. REM sleep near the sleep termination exerted important effects. Respiratory disturbance parameters were not related to sleep perception. There was a prolongation in the sleep latency in the first session of the MSLT and we suspected that a delayed sleep phase occurred in poor-sleep perceivers.
  
  
  CONCLUSIONS
  As an objectively good sleep does not match the subjective good-sleep perception in OSA, physicians should keep in mind that OSA patients who perceive that they have slept well does not mean that their OSA is less severe.
authors.affiliation: Department of Neurology, Seoul National University Boramae Hospital, Seoul, Korea.
authors.forename: Hyunwoo
authors.initials: H
authors.lastname: Nam
authors.affiliation: Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Lim
authors.affiliation: Department of Neurology, Seoul National University Boramae Hospital, Seoul, Korea.
authors.forename: Jun Soon
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Neurology, Seoul National University Boramae Hospital, Seoul, Korea.
authors.forename: Keon Joo
authors.initials: KJ
authors.lastname: Lee
authors.affiliation: Department of Neurology, Seoul National University Boramae Hospital, Seoul, Korea.
authors.forename: Dae Lim
authors.initials: DL
authors.lastname: Koo
authors.affiliation: Department of Otorhinolaryngology, Seoul National University Bundang Hospital, Seongnam, Korea. chulhee@snu.ac.kr.
authors.forename: Chulhee
authors.initials: C
authors.lastname: Lee
keywords: multiple sleep latency test; obstructive sleep apnea; polysomnography; sleep perception