title: The impact of obstructive sleep apnea and daytime sleepiness on work limitation.
abstract: BACKGROUND
  Many patients with obstructive sleep apnea (OSA) participate in the work force. However, the impact of OSA and sleepiness on work performance is unclear.
  
  
  METHODS
  To address this issue, we administered the Epworth Sleepiness Scale (ESS), the Work Limitations Questionnaire (WLQ), and an occupational survey to patients undergoing full-night polysomnography for the investigation of sleep-disordered breathing. Of 498 patients enrolled in the study, 428 (86.0%) completed the questionnaires. Their mean age+/-standard deviation (SD) was 49+/-12 years, mean body mass index (BMI) was 31+/-7 kg/m(2) mean apnea hypopnea index (AHI) was 21+/-22 events/h, and mean ESS score was 10+/-5. Subjects worked a mean of 39+/-18 h per week. The first 100 patients to complete the survey were followed up at two years.
  
  
  RESULTS
  In the group as a whole, there was no significant relationship between severity of OSA and the four dimensions of work limitation. However, in blue-collar workers, significant differences were detected between patients with mild OSA (AHI 5-15/h) and those with severe OSA (AHI>30/h) with respect to time management (limited 23.1% of the time vs. 43.8%, p=0.05) and mental/personnel interactions (17.9% vs. 33.0%, p=0.05). In contrast, there were strong associations between subjective sleepiness (as assessed by the ESS) and three of the four scales of work limitation. That is, patients with an ESS of 5 had much less work limitation compared to those with an ESS 18 in terms of time management (19.7% vs. 38.6 %, p<0.001), mental-interpersonal relationships (15.5% vs. 36.0%, p<0.001) and work output (16.8% vs. 36.0%; p<0.001). Of the group followed up, 49 returned surveys and 33 who were using continuous positive airway pressure (CPAP) showed significant improvements between the initial and second follow-up in time management (26% vs. 9%, p=0.0005), mental-interpersonal relationships (16% vs. 11.0%, p=0.014) and work output (18% vs. 10%; p<0.009).
  
  
  CONCLUSIONS
  We have demonstrated a clear relationship between excessive sleepiness and decreased work productivity in a population referred for suspected sleep-disordered breathing. Screening for sleepiness and sleep-disordered breathing in the workplace has the potential to identify a reversible cause of low work productivity.
authors.affiliation: Department of Medicine and Division of Respiratory Medicine, University of British Columbia, Vancouver, BC, Canada.
authors.forename: A T
authors.initials: AT
authors.lastname: Mulgrew
authors.forename: C F
authors.initials: CF
authors.lastname: Ryan
authors.forename: J A
authors.initials: JA
authors.lastname: Fleetham
authors.forename: R
authors.initials: R
authors.lastname: Cheema
authors.forename: N
authors.initials: N
authors.lastname: Fox
authors.forename: M
authors.initials: M
authors.lastname: Koehoorn
authors.forename: J M
authors.initials: JM
authors.lastname: Fitzgerald
authors.forename: C
authors.initials: C
authors.lastname: Marra
authors.forename: N T
authors.initials: NT
authors.lastname: Ayas
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis / Q000209:etiology*; D004526:Efficiency; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020181:Sleep Apnea, Obstructive / Q000150:complications*; D012892:Sleep Deprivation / Q000209:etiology; D011795:Surveys and Questionnaires; D014851:Wakefulness; D014937:Work; D017132:Workplace