Growth hormone secretion in children and adolescents at high risk for major depressive disorder

Background: Decreased growth hormone (GH) response to pharmacologic stimula tion has been found in children and adolescents during an episode of major depressive disorder and after recovery. In this study, we sought to determi ne whether GH secretion is similarly altered in children and adolescents wh o had never experienced depression but were at high risk of developing depr ession. Methods: Subjects were 8 through 16 years of age and selected for high- and low-risk status according to familial loading for mood disorders. Sixty-lo ur high-risk and 55 low-risk healthy subjects participated in the study, wh ich assessed the following GH measures: (1) GH before growth hormone-releas ing hormone (GHRH) infusion, every 15 minutes for 30 minutes; (2) GH respon se after intravenous infusion of GHRH (0.1 mu g/kg), every 15 minutes for 9 0 minutes; and (3) nocturnal GH every 20 minutes from 9 PM until morning aw akening. Results: After stimulation with GHRH, the high-risk subjects secreted signi ficantly less GH compared with the low-risk healthy controls (effect sizes for mean and peak GH, 0.52 [P = .007] and 0.40 [P=.04], respectively). In c ontrast, there were no between-group differences in the pre-GHRH and noctur nal GH secretion levels. Exposure to recent stressors was not associated wi th GH secretion. Conclusions: Taken together with previous evidence of decreased GH after GH RH infusion in acutely depressed and recovered children, these results indi cate that the decreased GH response found in high-risk subjects may represe nt a trait marker for depression in children and adolescents.