title: Growth Hormone Treatment Improves Cognitive Function in Short Children with Growth Hormone Deficiency.
abstract: OBJECTIVE
  We investigated the association between cognition and growth hormone (GH) status and GH treatment in short prepubertal children with broadly ranging GH secretion.
  
  
  METHODS
  A total of 99 children (age 3-11 years), 41 with GH deficiency (GHD) and 58 with idiopathic short stature (ISS), were randomized to a fixed dose (43 µg/kg/day) or a prediction model-guided individualized dose (17-100 µg/kg/day) and followed up for 24 months. In a longitudinal and mixed within- and between-subjects study, we examined clinical effect size changes, measured by Cohen's d, in full-scale IQ (FSIQ) and secondary IQ indices.
  
  
  RESULTS
  Significant increases giving medium effect size in FSIQ (p = 0.001, Cohen's d = 0.63), performance IQ (p = 0.001, Cohen's d = 0.65) and processing speed (p = 0.005, Cohen's d = 0.71) were found in the GH-deficient group. In contrast, perceptual organization only increased in the ISS group (p = 0.001, Cohen's d = 0.53). Baseline IQ was normally distributed with small but significant differences between the groups: GH-deficient children had lower FSIQ (p = 0.042) and lower performance IQ (p = 0.021). Using multiple regression analysis, 40% of the variance in delta processing speed scores (0-24 months) was explained by GHmaxand IGF-ISDSat baseline.
  
  
  CONCLUSIONS
  IQ, specifically fluid intelligence, increased in the GH-deficient children. The pretreatment status of the GH/IGF-I axis was significantly predictive for these changes. © 2015 S. Karger AG, Basel.
authors.affiliation: Gothenburg Pediatric Growth Research Center, Department of Pediatrics, Institute of Clinical Science, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: John Eric
authors.initials: JE
authors.lastname: Chaplin
authors.forename: Berit
authors.initials: B
authors.lastname: Kriström
authors.forename: Björn
authors.initials: B
authors.lastname: Jonsson
authors.forename: Torsten
authors.initials: T
authors.lastname: Tuvemo
authors.forename: Kerstin
authors.initials: K
authors.lastname: Albertsson-Wikland