title: Excessive daytime sleepiness increases the risk of motor vehicle crash in obstructive sleep apnea.
abstract: OBJECTIVE
  (1) To describe the incidence rate of motor vehicle crashes (MVCs) in patients with obstructive sleep apnea (OSA); and (2) to investigate MVC risk factors in OSA patients.
  
  
  METHODS
  A retrospective case-series observational study was conducted using data from the West Australian Sleep Health Study at a tertiary hospital-based sleep clinic. Participants were patients (N = 2,673) referred for assessment of suspected sleep disordered breathing. Questionnaire data were collected including age, sex, years of driving, near-misses and MVCs, sleepiness, and consumption of alcohol and caffeinated drinks. Overnight laboratory-based polysomnography was performed using standard methodology.(1) Poisson univariate and negative binomial multivariable regression models were used to investigate associations between risk factors and MVC and near-miss risk in patients with untreated OSA.
  
  
  RESULTS
  In patients with untreated OSA, the crash rate was 0.06 MVC/person-year compared with the general community crash rate of 0.02 MVC/person-year. The rate ratio comparing very sleepy men with normal men was 4.68 (95% CI 3.07, 7.14) for near-misses and 1.27 (95% CI 1.00, 1.61) for crashes, after adjusting for confounders. In women there was a significant association with sleepiness score (p = 0.02) but no dose effect across quartiles.
  
  
  CONCLUSIONS
  Untreated OSA is associated with an increased risk of near-misses in men and women and an increased risk of MVCs in very sleepy men. There is a strong association between excessive daytime sleepiness and increased report of near-misses. Our data support the observation that it is those patients with increased sleepiness regardless of OSA severity who are most at risk.
authors.affiliation: Centre for Genetic Origins of Health and Disease, The University of Western Australia, Perth, Australia ; Western Australian Sleep Disorders Research Institute, Queen Elizabeth II Medical Centre, Perth, Australia.
authors.forename: Kim L
authors.initials: KL
authors.lastname: Ward
authors.forename: David R
authors.initials: DR
authors.lastname: Hillman
authors.forename: Alan
authors.initials: A
authors.lastname: James
authors.forename: Alexandra P
authors.initials: AP
authors.lastname: Bremner
authors.forename: Laila
authors.initials: L
authors.lastname: Simpson
authors.forename: Matthew N
authors.initials: MN
authors.lastname: Cooper
authors.forename: Lyle J
authors.initials: LJ
authors.lastname: Palmer
authors.forename: Annette C
authors.initials: AC
authors.lastname: Fedson
authors.forename: Sutapa
authors.initials: S
authors.lastname: Mukherjee
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D001334:Automobile Driving; D015331:Cohort Studies; D006970:Disorders of Excessive Somnolence / Q000150:complications* / Q000175:diagnosis* / Q000628:therapy; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016012:Poisson Distribution; D017286:Polysomnography / Q000379:methods; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000175:diagnosis* / Q000628:therapy; D011795:Surveys and Questionnaires; D062606:Tertiary Care Centers; D014904:Western Australia
keywords: Motor vehicle crashes; gender; near-misses; obstructive sleep apnea; severity; sleepiness