Association of growth hormone deficiency (GHD) with anxiety and depression: experimental data and evidence from GHD children and adolescents

Anxiety and depression are among the commonest emotional problems in children and young adolescents. They are encountered with even higher prevalence in children and adults with growth hormone deficiency (GHD). Alterations in the somatotropic axis, as observed in both GH/IGF1 deficiency and excess, can produce permanent changes in brain tissue structure. The growth hormone/insulin-like growth factor 1 (GH/IGF1) axis seems to exert a regulatory effect on brain function and neurogenesis, especially in the hippocampus, a brain region associated with mental and emotional disorders, such as depression and anxiety. There is evidence from animal models of the possible interrelationship of the endocrine system with the pathogenesis of emotional disorders. Moreover, clinical data support the association of GHD and mood disorders, which are often reversed by GH replacement therapy. However, the causal relationship and the mechanism underlying this association are to date obscure and remain to be clarified. The present review reports experimental data from animal models regarding the role of GH/IGF1 in emotional disorders and focuses on clinical data on the presence of these disorders in children with GHD and their response to GH therapy.