title: Circadian rhythms of saliva melatonin in ADHD, anxious and normal children.
abstract: BACKGROUND
  Attention-deficit/hyperactivity disorder (ADHD) and anxiety disorders are the most frequent psychiatric disorders in children. Changes in rhythms of symptoms during the day may be influenced by genetic, biological and psychological factors. Some changes of melatonin rhythm may hypothetically change the activity of ADHD by changing arousal or in anxiety children by changing their emotional state. In our present study we identify one group of ADHD children combine type without comorbids, one group of anxiety children and a control group. Most changes of melatonin daily rhythm are supposed in the anxiety group, especially in sleeping time, and more prominent change in the ADHD group with prominent hyperactivity and conduct disorder symptoms.
  
  
  METHODS
  Thirty-four ADHD and forty-three control children and eleven anxiety children, all 6-12 years old, participated in the study. The saliva specimens were collected in four different sessions during the school year, around the time of the spring and autumn equinox, when the natural light lasted 11.2 h ± 0.9 h.
  
  
  CONCLUSIONS
  In our study more symptoms of conduct disorder elevated positive or negative correlations between psychopathology and saliva level of melatonin in ADHD and anxiety samples. We hypothesize that co-morbidity of ADHD or anxiety with impulsivity and conduct disorders might have elevated correlations between psychopathology of ADHD or anxiety and plasma melatonin level.
authors.affiliation: Department of Psychiatry, 1st Faculty of Medicine, Charles University, Prague, Czech Republic. ivopaclt@seznam.cz
authors.forename: Ivo
authors.initials: I
authors.lastname: Paclt
authors.forename: Radek
authors.initials: R
authors.lastname: Ptácek
authors.forename: Hana
authors.initials: H
authors.lastname: Kuzelová
authors.forename: Nikol
authors.initials: N
authors.lastname: Cermáková
authors.forename: Alexandra
authors.initials: A
authors.lastname: Trefilová
authors.forename: Patricie
authors.initials: P
authors.lastname: Kollárová
authors.forename: Tereza
authors.initials: T
authors.lastname: Cálková
authors.forename: Ladislav
authors.initials: L
authors.lastname: Csemy
authors.forename: Libor
authors.initials: L
authors.lastname: Cíhal
mesh_terms: D001008:Anxiety Disorders / Q000378:metabolism*; D001289:Attention Deficit Disorder with Hyperactivity / Q000378:metabolism*; D002648:Child; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D008550:Melatonin / Q000378:metabolism*; D012463:Saliva / Q000737:chemistry*
chemical_list: D008550:Melatonin