title: Cognitive effects of aromatase inhibitor therapy in peripubertal boys.
abstract: OBJECTIVE
  Aromatase inhibitors, blockers of oestrogen biosynthesis, have emerged as a new potential treatment modality for boys with short stature. The cognitive effects of such therapy are unknown. In this study, we explored the effects of aromatase inhibition on cognitive performance in peripubertal boys.
  
  
  METHODS
  Prospective, double-blind, randomised, placebo-controlled clinical study.
  
  
  METHODS
  Twenty-eight boys, aged 9.0-14.5 years, with idiopathic short stature were treated with the aromatase inhibitor letrozole (2.5 mg/day) or placebo, for 2 years. During the treatment, the progression of physical signs of puberty and the concentrations of sex hormones were followed up. A selection of cognitive tests, focusing on memory function, was administered to the participants at entry, at 12 months and at 24 months after the start of the treatment.
  
  
  RESULTS
  Letrozole effectively inhibited the conversion of androgen to oestrogen, as indicated by high serum testosterone and low serum oestradiol concentrations in letrozole-treated boys who progressed into puberty. In both the groups, there was a gain in performance during the follow-up period in tests of verbal performance, in most of the tests of visuospatial performance and in some tests of verbal memory. No significant differences between the letrozole- and placebo-treated boys in development of cognitive performance were found in any of the tests during the follow-up period.
  
  
  CONCLUSIONS
  Our results suggest that blockade of oestrogen biosynthesis with an aromatase inhibitor does not influence cognitive performance in peripubertal males.
authors.affiliation: Hospital for Children and Adolescents, University of Helsinki and Helsinki University Central Hospital, PO Box 448, FIN-00029 HUS Helsinki, Finland. matti.hero@hus.fi
authors.forename: M
authors.initials: M
authors.lastname: Hero
authors.forename: S
authors.initials: S
authors.lastname: Maury
authors.forename: E
authors.initials: E
authors.lastname: Luotoniemi
authors.forename: E
authors.initials: E
authors.lastname: Service
authors.forename: L
authors.initials: L
authors.lastname: Dunkel
mesh_terms: D000293:Adolescent; D047072:Aromatase Inhibitors / Q000627:therapeutic use*; D002648:Child; D003071:Cognition / Q000187:drug effects; D004311:Double-Blind Method; D006130:Growth Disorders / Q000188:drug therapy; D006801:Humans; D000077289:Letrozole; D008297:Male; D009570:Nitriles / Q000627:therapeutic use*; D014230:Triazoles / Q000627:therapeutic use*
chemical_list: D047072:Aromatase Inhibitors; D009570:Nitriles; D014230:Triazoles; D000077289:Letrozole