Growth Hormone Response May Be Trait Marker for Depression
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WESTPORT, Sep 15 (Reuters Health) - A decrease in growth hormone response following exposure to growth hormone-releasing hormone in children and adolescents may be a trait marker for major depressive disorder, according to a report published in the September issue of the Archives of General Psychiatry.

Dr. Boris Birmaher, of Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania, and colleagues evaluated the growth hormone responses of 64 children ages 8 to 16 years who were considered at high risk for depression because of a family history of mood disorders. None had yet been diagnosed with major depression themselves. Also included in the study were 55 low-risk healthy subjects.

Growth hormone-releasing hormone 1.0 mcg/kg was infused intravenously for 2 minutes, then blood samples, taken every 15 minutes for 90 minutes, were analyzed for growth hormone levels.

After adjusting for age, sex, body mass index, and Tanner stage, the investigators observed significantly lower mean and peak growth hormone response in the high-risk subjects than in the control subjects. This relationship was maintained after they excluded the high-risk group subjects with nonaffective psychiatric disorders.

According to Dr. Birmaher's group, these results are similar to those obtained with depressed children and adolescents, acutely depressed patients across the age span, and individuals who have recovered from depression.

These results also suggest that "the dysregulation of the growth hormone response to growth hormone-releasing hormone might be a trait marker that antedates the onset of a depressive episode," the investigators conclude.

"If we can use this test to see which kids are at high risk for depression," Dr. Birmaher told Reuters Health, "then we can treat them before they get depressed." He added that previous studies show cognitive behavioral therapy helps prevent the development of depression in children at high risk.

Arch Gen Psychiatry 2000;57:867-872.