title: The role of poor sleep in the relation between workplace bullying/unwanted sexual attention and long-term sickness absence.
abstract: OBJECTIVE
  While exposure to bullying and unwanted sexual attention was previously found to increase the risk of sickness absence, the underlying mechanisms are largely unknown. Poor sleep can be a consequence of stressful exposures and a cause of poor health, and poor sleep is also a determinant of insufficient recovery. Therefore, the present study investigated whether poor sleep mediates and/or moderates the association between bullying and unwanted sexual attention, on the one hand, and long-term sickness absence (LTSA), on the other hand.
  
  
  METHODS
  We used questionnaire data from 7650 individuals contributing with 15,040 2-year observation periods. Workplace bullying, unwanted sexual attention, disturbed sleep, and difficulties awakening were measured at three time points, and participants were followed in registers to measure the occurrence of LTSA, defined as ≥30 consecutive days of sickness absence during the subsequent 2 years.
  
  
  RESULTS
  The odds of LTSA were significantly increased by workplace bullying (OR 1.77; 95 % CI 1.50-2.12) and unwanted sexual attention (OR 1.55; 95 % CI 1.06-2.29). Together, disturbed sleep and difficulties awakening mediated 12.8 % (95 % CI 8.1-19.8) of the association between bullying and long-term sickness absence, and 8.5 % (95 % CI -0.45 to 37.1) of the association between unwanted sexual attention and long-term sickness absence in the fully adjusted model. Neither disturbed sleep nor difficulties awakening moderated these associations.
  
  
  CONCLUSIONS
  As expected, bullying and unwanted sexual attention were prospectively associated with long-term sickness absence. Only a small part of this association was mediated by poor sleep.
authors.affiliation: Centre for Health and Society, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, 1014, Copenhagen K, Denmark. nabe@sund.ku.dk.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Nabe-Nielsen
authors.affiliation: Centre for Health and Society, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, 1014, Copenhagen K, Denmark.
authors.forename: Matias Brødsgaard
authors.initials: MB
authors.lastname: Grynderup
authors.affiliation: Centre for Health and Society, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, 1014, Copenhagen K, Denmark.|Center for Statistical Science, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing, 100871, People's Republic of China.
authors.forename: Theis
authors.initials: T
authors.lastname: Lange
authors.affiliation: Danish Ramazzini Centre, Department of Occupational Medicine, University Research Clinic, Regional Hospital West Jutland, Gl. Landevej 61, 7400, Herning, Denmark.
authors.forename: Johan Hviid
authors.initials: JH
authors.lastname: Andersen
authors.affiliation: Department of Occupational and Environmental Medicine, Bispebjerg-Frederiksberg University Hospital, Bispebjerg Bakke 23, 2400, Copenhagen NV, Denmark.
authors.forename: Jens Peter
authors.initials: JP
authors.lastname: Bonde
authors.affiliation: Department of Psychology, University of Copenhagen, Øster Farimagsgade 2A, 1353, Copenhagen K, Denmark.
authors.forename: Paul Maurice
authors.initials: PM
authors.lastname: Conway
authors.affiliation: Centre for Health and Society, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, 1014, Copenhagen K, Denmark.|The National Research Centre for the Working Environment, Lersø Parkallé 105, 2100, Copenhagen Ø, Denmark.
authors.forename: Anne Helene
authors.initials: AH
authors.lastname: Garde
authors.affiliation: Department of Psychology, University of Copenhagen, Øster Farimagsgade 2A, 1353, Copenhagen K, Denmark.
authors.forename: Annie
authors.initials: A
authors.lastname: Høgh
authors.affiliation: Research Unit of Clinical Epidemiology, Institute of Clinical Research, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark.|Center for Clinical Epidemiology, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense C, Denmark.
authors.forename: Linda
authors.initials: L
authors.lastname: Kaerlev
authors.affiliation: Centre for Health and Society, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, 1014, Copenhagen K, Denmark.|Department of Psychology, University of Copenhagen, Øster Farimagsgade 2A, 1353, Copenhagen K, Denmark.|The National Research Centre for the Working Environment, Lersø Parkallé 105, 2100, Copenhagen Ø, Denmark.
authors.forename: Reiner
authors.initials: R
authors.lastname: Rugulies
authors.affiliation: Centre for Health and Society, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, 1014, Copenhagen K, Denmark.|The National Research Centre for the Working Environment, Lersø Parkallé 105, 2100, Copenhagen Ø, Denmark.
authors.forename: Åse Marie
authors.initials: ÅM
authors.lastname: Hansen
mesh_terms: D000041:Absenteeism; D000328:Adult; D058445:Bullying; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000523:psychology*; D011446:Prospective Studies; D012742:Sex Offenses / Q000523:psychology; D018582:Sick Leave / Q000706:statistics & numerical data; D012893:Sleep Wake Disorders / Q000523:psychology*; D011795:Surveys and Questionnaires; D017132:Workplace / Q000523:psychology*; D064450:Workplace Violence / Q000523:psychology*
keywords: Mediation; Moderation; Negative acts; Offensive behavior; Sexual harassment; Sick leave