title: Nightly sleep duration in the 2-week period preceding multiple sleep latency testing.
abstract: OBJECTIVE
  To assess usual nightly sleep duration of patients referred for a Multiple Sleep Latency Test (MSLT).
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  Military, hospital-based, sleep center.
  
  
  METHODS
  Fifty-four patients with excessive daytime sleepiness referred for an MSLT.
  
  
  METHODS
  None.
  
  
  RESULTS
  Self-reported average nightly sleep duration (6.13 +/- 1.23 hours), sleep log-recorded average nightly sleep duration (6.99 +/- 0.85 hours), and actigraphy-measured average nightly sleep duration (5.56 +/- 1.50 hours) were compared for the 2-week period immediately preceding an MSLT One-way analysis of variance revealed a significant difference in the 3 estimates of nightly sleep duration (p < 0.0001), and only actigraphy-measured average nightly sleep duration correlated with mean sleep latency on the MSLT (r = 0.4258, p = 0.0016). Subgroup analysis showed that patients with a mean sleep latency shorter than 8 minutes slept an average of 1.57 hours less per night than did those patients with a mean sleep latency of 8 minutes or longer (4.53 +/- 1.37 vs 6.10 +/- 1.37 hours per night, p < 0.001) as measured by actigraphy. There was no difference in either self-reported average nightly sleep duration or sleep log-recorded average nightly sleep duration between the 2 subgroups.
  
  
  CONCLUSIONS
  Prolonged actigraphy monitoring may provide useful clinical information about pre-MSLT sleep not always obtainable from patient self-reporting or sleep logs.
authors.affiliation: Department of Internal Medicine, Pulmonary Division, Naval Medical Center San Diego, San Diego, CA 92134, USA. david.bradshaw@med.navy.mil
authors.forename: David A
authors.initials: DA
authors.lastname: Bradshaw
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Yanagi
authors.forename: Edward S
authors.initials: ES
authors.lastname: Pak
authors.forename: Terry S
authors.initials: TS
authors.lastname: Peery
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Ruff
mesh_terms: D000328:Adult; D003071:Cognition; D015897:Comorbidity; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009290:Narcolepsy / Q000175:diagnosis* / Q000453:epidemiology; D017286:Polysomnography / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012894:Sleep Stages / Q000502:physiology*; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology*