title: Stress reactivity predicts symptom improvement in children with anxiety disorders.
abstract: BACKGROUND
  We examined the longitudinal associations of autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis rest and reactivity measures with anxiety and depressive symptoms at one-year follow-up in children with anxiety disorders.
  
  
  METHODS
  In a clinical sample of 152 children with a primary DSM-IV anxiety disorder, aged 8 to 12 years, anxiety and depressive symptoms were assessed with the Multidimensional Anxiety Scale for Children and the Children's Depression Inventory at pre-treatment baseline and one year later, after treatment with cognitive behavioral therapy. At baseline, children participated in a 70min stress task. Salivary cortisol was measured directly prior to and 20min post stress task. Skin conductance level (SCL), heart rate and high frequency heart rate variability (HRV) were continuously measured during rest and the stress task. To investigate if rest or reactivity measures predicted anxiety and depressive symptoms at one year follow-up, linear regression analyses were conducted for rest and reactivity measures of SCL, heart rate, HRV and cortisol separately.
  
  
  RESULTS
  Higher SCL reactivity predicted less decrease of anxiety symptoms at one-year follow-up. Cortisol reactivity showed a weak association with depressive symptoms at one-year follow-up: lower cortisol reactivity predicted less decrease in depressive symptoms.
  
  
  CONCLUSIONS
  Only self-reported anxiety and depressive symptoms were used. However, all predictors were objective biological measures, hence there is no risk of shared method variance bias.
  
  
  CONCLUSIONS
  These findings suggest that pre-treatment HPA and ANS responsiveness to stress are predictive biomarkers for a lack of symptom improvement in children with a clinical anxiety disorder.
authors.affiliation: Department of Child and Adolescent Psychiatry/Psychology, Erasmus Medical Center Rotterdam/Sophia Children's Hospital, Rotterdam, The Netherlands. Electronic address: g.dieleman@erasmusmc.nl.
authors.forename: Gwendolyn C
authors.initials: GC
authors.lastname: Dieleman
authors.affiliation: Department of Developmental Psychology, Faculty of Psychology and Education, VU University, Amsterdam, The Netherlands.
authors.forename: Anja C
authors.initials: AC
authors.lastname: Huizink
authors.affiliation: Department of Psychiatry, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Joke H M
authors.initials: JH
authors.lastname: Tulen
authors.affiliation: Department of Child and Adolescent Psychiatry/Psychology, Erasmus Medical Center Rotterdam/Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Elisabeth M W J
authors.initials: EM
authors.lastname: Utens
authors.affiliation: Department of Child and Adolescent Psychiatry/Psychology, Erasmus Medical Center Rotterdam/Sophia Children's Hospital, Rotterdam, The Netherlands; Department of Psychiatry, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Henning
authors.initials: H
authors.lastname: Tiemeier
mesh_terms: D001008:Anxiety Disorders / Q000503:physiopathology* / Q000628:therapy*; D001341:Autonomic Nervous System / Q000503:physiopathology*; D002648:Child; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology; D008297:Male; D010913:Pituitary-Adrenal System / Q000503:physiopathology; D016896:Treatment Outcome
chemical_list: D006854:Hydrocortisone
keywords: Anxiety disorders; Autonomic nervous system; Cognitive behavioral therapy; Cortisol; Depressive symptoms; Treatment outcome