title: Chronicity of sleep problems in children with chronic illness: a longitudinal population-based study.
abstract: BACKGROUND
  The aim of this study was to examine the chronicity of sleep problems in children with chronic illness, and potential predictors of sleep problems.
  
  
  METHODS
  Using data from a longitudinal total population study in Norway, The Bergen Child Study, data on sleep problems, chronic illness and potential confounders were assessed at ages 79 and 1113.
  
  
  RESULTS
  295 of 4025 (7.3%) children had a chronic illness, and the prevalence of chronic sleep problems was significantly higher in this group compared to children without chronic illness (6.8% versus 3.6%). Sleep problems at the first wave increased the risk of sleep problems at the second wave, also when adjusting for potential confounders (odds-ratio = 5.41). Hyperactivity and emotional problems were also independent risk factors for later sleep problems.
  
  
  CONCLUSIONS
  These findings call for increased awareness and development of treatment strategies of sleep problems in children with chronic illness.
authors.affiliation: Department of Clinical Psychology, University of Bergen, Bergen, Norway. borge.sivertsen@psykp.uib.no
authors.forename: Børge
authors.initials: B
authors.lastname: Sivertsen
authors.forename: Mari
authors.initials: M
authors.lastname: Hysing
authors.forename: Irene
authors.initials: I
authors.lastname: Elgen
authors.forename: Kjell Morten
authors.initials: KM
authors.lastname: Stormark
authors.forename: Astri J
authors.initials: AJ
authors.lastname: Lundervold