title: Reduced hair cortisol after maltreatment mediates externalizing symptoms in middle childhood and adolescence.
abstract: BACKGROUND
  The enduring impact of childhood maltreatment on biological systems and ensuing psychopathology remains incompletely understood. Long-term effects of stress may be reflected in cumulative cortisol secretion over several months, which is now quantifiable via hair cortisol concentrations (HCC). We conducted a first comprehensive investigation utilizing the potential of hair cortisol analysis in a large sample of maltreated and nonmaltreated children and adolescents.
  
  
  METHODS
  Participants included 537 children and adolescents (3-16 years; 272 females) with maltreatment (n = 245) or without maltreatment histories (n = 292). Maltreated subjects were recruited from child protection services (CPS; n = 95), youth psychiatric services (n = 56), and the community (n = 94). Maltreatment was coded using the Maltreatment Classification System drawing on caregiver interviews and complemented with CPS records. Caregivers and teachers reported on child mental health. HCC were assessed in the first 3 cm hair segment.
  
  
  RESULTS
  Analyses uniformly supported that maltreatment coincides with a gradual and dose-dependent reduction in HCC from 9 to 10 years onwards relative to nonmaltreated controls. This pattern emerged consistently from both group comparisons between maltreated and nonmaltreated subjects (27.6% HCC reduction in maltreated 9-16-year-olds) and dimensional analyses within maltreated subjects, with lower HCC related to greater maltreatment chronicity and number of subtypes. Moreover, both group comparisons and dimensional analyses within maltreated youth revealed that relative HCC reduction mediates the effect of maltreatment on externalizing symptoms.
  
  
  CONCLUSIONS
  From middle childhood onwards, maltreatment coincides with a relative reduction in cortisol secretion, which, in turn, may predispose to externalizing symptoms.
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Lars O
authors.initials: LO
authors.lastname: White
authors.affiliation: Max Planck Institute of Psychiatry, Munich, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Ising
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: von Klitzing
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Susan
authors.initials: S
authors.lastname: Sierau
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.|Department of Developmental Psychology, University of Jena, Jena, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Michel
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Annette M
authors.initials: AM
authors.lastname: Klein
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Andreas
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Keil
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Leipzig, Leipzig, Germany.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Quintero
authors.affiliation: Max Planck Institute of Psychiatry, Munich, Germany.|Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.|Institute of Translational Medicine, University of Liverpool, Liverpool, UK.
authors.forename: Bertram
authors.initials: B
authors.lastname: Müller-Myhsok
authors.affiliation: Max Planck Institute of Psychiatry, Munich, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Uhr
authors.affiliation: University of Leipzig, Leipzig, Germany.
authors.forename: Ruth
authors.initials: R
authors.lastname: Gausche
authors.affiliation: Mt. Hope Family Center, University of Rochester, Rochester, NY, USA.
authors.forename: Jody T
authors.initials: JT
authors.lastname: Manly
authors.affiliation: Yale Child Study Center, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Crowley
authors.affiliation: Institute of Psychology, TU Dresden, Dresden, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Kirschbaum
authors.affiliation: Institute of Psychology, TU Dresden, Dresden, Germany.|Clinical Psychology, University of Siegen, Siegen, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Stalder
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology*; D001526:Behavioral Symptoms / Q000378:metabolism* / Q000503:physiopathology*; D002648:Child; D002649:Child Abuse; D002652:Child Behavior / Q000502:physiology*; D002675:Child, Preschool; D005260:Female; D006197:Hair / Q000737:chemistry*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male
chemical_list: D006854:Hydrocortisone
keywords: Hair cortisol; externalizing symptoms; maltreatment; neglect