title: Sex-specific prediction of hypothalamic-pituitary-adrenal axis activity by pituitary volume during adolescence: a longitudinal study from 12 to 17 years of age.
abstract: OBJECTIVE
  To investigate the longitudinal relationship between pituitary gland volume (PGV) and parameters of hypothalamic-pituitary-adrenal axis (HPAA) functioning during adolescence.
  
  
  METHODS
  Participants were 49 adolescents (19 girls and 30 boys) selected from a larger longitudinal, population-based study of adolescent development. Assessments were conducted at three time points (S1, S2 and S3). MRI sessions were at S1 (age: M=12.62, SD=0.45 years) and S3 (M=16.48, SD=0.53 years) and multiple assessments of salivary cortisol were undertaken at S2 (M=15.51, SD=0.35 years). PGV was measured via previously validated manual tracing methods, and the cortisol awakening response (CAR) and diurnal slope (DSL) were used as indices of HPAA functioning.
  
  
  RESULTS
  A significant sex-linked interaction was found for PGV at S1 predicting both CAR (p=0.025) and DSL (p=0.009) at S2. Specifically, PGV at S1 significantly predicted CAR (p=0.033) and DSL (p=0.010) in boys only, with no significant results found for girls. Neither CAR nor DSL at S2 predicted growth of PGV from S1 to S3.
  
  
  CONCLUSIONS
  PGV in early adolescence predicted HPAA functioning in mid-adolescent boys but not in girls. The results suggest a significant influence of sex-specific development on the relationship between PGV and HPAA activity and reactivity. The findings have potential implications for understanding and interpreting sex-linked and stress related clinical disorders that emerge during mid-to-late adolescence.
authors.affiliation: Orygen Youth Health Clinical Program, Northwestern Mental Health, Melbourne, Australia; Section for Disorders of Personality Development, Department of Child and Adolescent Psychiatry, Centre for Psychosocial Medicine, University of Heidelberg, Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Kaess
authors.forename: Julian G
authors.initials: JG
authors.lastname: Simmons
authors.forename: Sarah
authors.initials: S
authors.lastname: Whittle
authors.forename: Martina
authors.initials: M
authors.lastname: Jovev
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Chanen
authors.forename: Murat
authors.initials: M
authors.lastname: Yücel
authors.forename: Christos
authors.initials: C
authors.lastname: Pantelis
authors.forename: Nicholas B
authors.initials: NB
authors.lastname: Allen
mesh_terms: D000293:Adolescent; D041923:Adolescent Development / Q000502:physiology*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D008137:Longitudinal Studies; D008297:Male; D059906:Neuroimaging; D010902:Pituitary Gland / Q000254:growth & development* / Q000378:metabolism; D010913:Pituitary-Adrenal System / Q000254:growth & development* / Q000502:physiology*; D012463:Saliva / Q000378:metabolism; D012727:Sex Characteristics; D014851:Wakefulness / Q000502:physiology
chemical_list: D006854:Hydrocortisone
keywords: Adolescence; Cortisol; Development; HPA axis; Pituitary; Sex