Corticotropin-releasing hormone challenge in prepubertal major depression

This study investigates cortisol and ACTH (corticotropin) responses to an infusion of human CRH (corticotropin-releasing hormone) in prepubertal children with major depressive disorder (MDD). Following a period of 24 hours of adaptation to the laboratory environment with an intravenous catheter in place, 34 children with MDD and 22 healthy controls received 1 μg/kg of human CRH at 5:00 PM. Blood samples for cortisol and ACTH were measured at baseline and post-CRH. Overall, there were no significant differences between the MDD and the normal controls in baseline or post CRH stimulation values of either cortisol or ACTH. Melancholic (n = 4) patients had significantly higher baseline cortisol levels than nonmelancholic (n = 24) patients. Compared with the outpatients and the nonmelancholics, the inpatients (n = 10) and the melancholics showed significantly lower total ACTH secretion (effect size: 0.9 and 1.4, respectively) after CRH infusion. These results are consistent with a broad literature suggesting that the HPA axis abnormalities occur less frequently in early-onset depression than reported in adult studies. The pattern of results in the subgroups of inpatients and in melancholic children, however, raise questions about possible continuities with adult studies.