title: Sleep disturbances and serum ferritin levels in children with attention-deficit/hyperactivity disorder.
abstract: BACKGROUND
  A subset of children with attention-deficit/hyperactivity disorder (ADHD) may present with impairing sleep disturbances. While preliminary evidence suggests that iron deficiency might be involved into the pathophysiology of daytime ADHD symptoms, no research has been conducted to explore the relationship between iron deficiency and sleep disturbances in patients with ADHD. The aim of this study was to assess the association between serum ferritin levels and parent reports of sleep disturbances in a sample of children with ADHD.
  
  
  METHODS
  
  
  
  METHODS
  Sixty-eight consecutively referred children (6-14 years) with ADHD diagnosed according to DSM-IV criteria using the semi-structured interview Kiddie-SADS-PL.
  
  
  METHODS
  parents filled out the Sleep Disturbance Scale for Children (SDSC) and the Conners Parent Rating Scale (CPRS). Serum ferritin levels were determined using the Tinaquant method.
  
  
  RESULTS
  Compared to children with serum ferritin levels >or=45 microg/l, those with serum ferritin levels <45 microg/l had significantly higher scores on the SDSC subscale "Sleep wake transition disorders" (SWTD) (P = 0.042), which includes items on abnormal movements in sleep, as well as significantly higher scores on the CPRS-ADHD index (P = 0.034). The mean scores on the other SDSC subscales did not significantly differ between children with serum ferritin >or=45 and <45 microg/l. Serum ferritin levels were inversely correlated to SWTD scores (P = 0.043).
  
  
  CONCLUSIONS
  Serum ferritin levels <45 microg/l might indicate a risk for sleep wake transition disorders, including abnormal sleep movements, in children with ADHD. Our results based on questionnaires set the basis for further actigraphic and polysomnographic studies on nighttime activity and iron deficiency in ADHD. Research in this field may suggest future trials of iron supplementation (possibly in association with ADHD medications) for abnormal sleep motor activity in children with ADHD.
authors.affiliation: AP-HP, Child and Adolescent Psychopathology Unit, Robert Debré Hospital, Paris VII University, Paris, France. samuele.cortese@gmail.com
authors.forename: Samuele
authors.initials: S
authors.lastname: Cortese
authors.forename: Eric
authors.initials: E
authors.lastname: Konofal
authors.forename: Bernardo Dalla
authors.initials: BD
authors.lastname: Bernardina
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Mouren
authors.forename: Michel
authors.initials: M
authors.lastname: Lecendreux
mesh_terms: D000293:Adolescent; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000453:epidemiology; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005293:Ferritins / Q000097:blood*; D006801:Humans; D008297:Male; D020189:Nocturnal Myoclonus Syndrome / Q000453:epidemiology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012893:Sleep Wake Disorders / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology*
chemical_list: D005293:Ferritins