title: The role of sleep-disordered breathing, daytime sleepiness, and impaired performance in motor vehicle crashes-a case control study.
abstract: OBJECTIVE
  To examine levels of sleep-disordered breathing, daytime sleepiness, and impaired performance in 60 motor vehicle crash drivers and 60 controls matched for age, gender, and body mass index.
  
  
  RESULTS
  All participants underwent polysomnography and daytime function assessments. Cases reported significantly higher levels of driver sleepiness (% sleepiness: mean +/- SD; cases: 26 +/- 17%; controls: 16 +/- 12%; p = 0.003) and demonstrated slower reaction times on a sustained attention task ( p = 0.02). There was a trend for more objective sleepiness in cases (maintenance of wakefulness test: cases: 17 +/- 4 minutes; controls: 18 +/- 3 minutes, p = 0.06) despite no differences in general subjective sleepiness (Epworth score: cases: 8 +/- 4; controls: 8 +/- 4; p = 0.93). There were no significant differences in polysomnography measures between groups (apneas + hypopneas per hour slept: cases: 8 +/- 9; controls: 9 +/- 16; p = 0.89; arousals per hour slept: cases: 18 +/- 8; controls: 21 +/- 12; p = 0.11).
  
  
  CONCLUSIONS
  Crash drivers demonstrated significantly more driver sleepiness, slower reaction times and a trend for greater objective sleepiness compared with well-matched controls. However, the findings in crash drivers were independent of medical causes of sleep fragmentation, with both cases and controls showing moderate levels of unrecognized mild sleep-disordered breathing. Crash prevention strategies should focus on increasing personal awareness of the risks of sleepiness behind the wheel in all individuals.
authors.affiliation: Department of Respiratory Research, University of Otago, Dunedin, New Zealand. resp.med@stonebow.otago.ac.nz
authors.forename: Ruth N
authors.initials: RN
authors.lastname: Kingshott
authors.forename: Jan O
authors.initials: JO
authors.lastname: Cowan
authors.forename: David R
authors.initials: DR
authors.lastname: Jones
authors.forename: Erin M
authors.initials: EM
authors.lastname: Flannery
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Smith
authors.forename: G Peter
authors.initials: GP
authors.lastname: Herbison
authors.forename: D Robin
authors.initials: DR
authors.lastname: Taylor
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000328:Adult; D001334:Automobile Driving / Q000706:statistics & numerical data*; D015992:Body Mass Index; D016022:Case-Control Studies; D002940:Circadian Rhythm; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis / Q000453:epidemiology*; D004569:Electroencephalography; D005221:Fatigue / Q000453:epidemiology; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D011930:Reaction Time; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000175:diagnosis / Q000453:epidemiology*; D011795:Surveys and Questionnaires