Growth hormone secretion in prepubertal children with major depression. IV. Sleep-related plasma concentrations in a drug-free, fully recovered clinical state.

Prepubertal children with major depressive disorder have shown increased growth hormone (GH) secretion during sleep while in a depressive episode. When restudied in a fully recovered state (for at least three months) and drug free (for at least one month), their increased GH secretory pattern during sleep had not changed. Illness-recovery correlations using area under the curve for GH secretion during sleep were highly significant, whereas paired comparisons showed no significant differences. In addition, children who had recovered from major depressive episodes secreted significantly more GH during sleep than did nondepressed neurotic and normal children. No significant differences in delta-sleep were found in the depressed group between ill and recovered states nor among those who had recovered from major depressive episodes or controls. It is concluded that increased GH secretion during sleep is independent of depressive episodes, remains unaltered after full recovery, and may be a true marker of trait for major depressive disorder in prepuberty.