title: Predictors of shift work disorder among nurses: a longitudinal study.
abstract: BACKGROUND
  Shift work is associated with sleep problems and impaired health. The main aim of the present study was to explore predictors of developing shift work disorder (SWD) among Norwegian nurses using a longitudinal design.
  
  
  METHODS
  A total of 1533 nurses participating in a survey on shift work, sleep and health responded to questionnaires at baseline and at follow-up about two years later. SWD was defined as problems of excessive sleepiness and/or complaints of insomnia related to the work schedule.
  
  
  CONCLUSIONS
  There was a significant reduction (p < 0.001) in the prevalence of SWD from baseline to follow-up, from 35.7% to 28.6%. Logistic regression analyses showed significant risks of having SWD at follow-up and the following variables measured at baseline: number of nights worked the last year (OR = 1.01, 95% CI = 1.01-1.02), having SWD (OR = 5.19, 95% CI = 3.74-7.20), composite score on the Epworth Sleepiness Scale (OR = 1.08, 95% CI = 1.04-1.13), use of melatonin (OR = 4.20, 95% CI = 1.33-13.33), use of bright light therapy (OR = 3.10, 95% CI 1.14-8.39), and symptoms of depression measured by the Hospital Anxiety and Depression Scale (OR = 1.07, 95% CI = 1.00-1.14). In addition, leaving night work between baseline and follow-up was associated with a significantly reduced risk of SWD at follow-up (OR = 0.12, 95% CI = 0.07-0.22).
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway; Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway. Electronic address: siri.waage@isf.uib.no.
authors.forename: Siri
authors.initials: S
authors.lastname: Waage
authors.affiliation: Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway; Department of Psychosocial Science, University of Bergen, Bergen, Norway.
authors.forename: Ståle
authors.initials: S
authors.lastname: Pallesen
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway; Centre for International Health, University of Bergen, Bergen, Norway.
authors.forename: Bente Elisabeth
authors.initials: BE
authors.lastname: Moen
authors.affiliation: Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: Nils
authors.initials: N
authors.lastname: Magerøy
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway; Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Flo
authors.affiliation: School of Management and the Institute for Health and Social Science Research, Rockhampton, Central Queensland University, Qld, Australia.
authors.forename: Lee
authors.initials: L
authors.lastname: Di Milia
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway; Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway.
authors.forename: Bjørn
authors.initials: B
authors.lastname: Bjorvatn
mesh_terms: D000328:Adult; D001007:Anxiety / Q000453:epidemiology / Q000209:etiology; D003863:Depression / Q000453:epidemiology / Q000209:etiology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009726:Nurses / Q000706:statistics & numerical data*; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D020178:Sleep Disorders, Circadian Rhythm / Q000453:epidemiology* / Q000209:etiology; D011795:Surveys and Questionnaires; D014940:Work Schedule Tolerance; D055815:Young Adult
keywords: Insomnia; Shift work; Shift work disorder; Sleep problems; Sleepiness