title: Reduced salivary cortisol in children with comorbid Attention deficit hyperactivity disorder and oppositional defiant disorder.
abstract: OBJECTIVE
  There is growing interest in the role of the hypothalamic-pituitary-adrenal (HPA) axis in neuropsychiatric disorders and there is some evidence that the HPA axis may be underfunctional in behaviorally disturbed children. However, co-morbidity is common in childhood neuropsychiatric disorders. Stimulant medication is widely used in the treatment of Attention-deficit hyperactivity disorder (ADHD) and can increase cortisol secretion when given acutely. We therefore set out to determine the whether salivary cortisol would be reduced in a group of children with ADHD/ODD (Oppositional-defiant disorder) and to examine the effect of stimulant medication on any such relationship.
  
  
  METHODS
  Salivary cortisol was determined in thirty-two children with co-morbid ADHD and Oppositional-defiant disorder (ODD) according to DSM-IV criteria, compared to twenty-five healthy controls of similar age and ethnic background. Data were analysed according to prescription of stimulant medication in the patient group.
  
  
  RESULTS
  Salivary cortisol was significantly lower in the ADHD/ODD group than in the controls. Further analysis revealed that this reduction was restricted to the subgroup of patients not prescribed stimulant medication.
  
  
  CONCLUSIONS
  The results support the possibility of a dysfunction of control of the HPA axis in these behaviorally disturbed children. A reduction in salivary cortisol could reflect underarousal, an elevated threshold for detection of stressors or a subsensitivity of the HPA axis itself. It remains to be determined whether the ability of stimulant medications to negate the apparent deficit in cortisol secretion in these ADHD/ODD patients is an unrelated consequence of increased dopamine release or a reflection of their therapeutic benefit. The use of stimulant medication for co-existing ADHD should be taken into account in future studies of cortisol in behaviorally disturbed children.
authors.affiliation: Diana, Princess of Wales Children's Hospital, Birmingham, UK.
authors.forename: S Himani
authors.initials: SH
authors.lastname: Kariyawasam
authors.forename: Frank
authors.initials: F
authors.lastname: Zaw
authors.forename: Sheila L
authors.initials: SL
authors.lastname: Handley
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy / Q000378:metabolism*; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000378:metabolism*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use; D002648:Child; D003913:Dextroamphetamine / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008774:Methylphenidate / Q000627:therapeutic use; D012016:Reference Values; D012463:Saliva / Q000378:metabolism*
chemical_list: D000697:Central Nervous System Stimulants; D008774:Methylphenidate; D003913:Dextroamphetamine; D006854:Hydrocortisone