Pituitary volume in treatment-naïve pediatric major depressive disorder.

BACKGROUND: Prior pilot investigation identified a larger pituitary gland volume (PGV) in pediatric patients with major depressive disorder (MDD) compared with healthy pediatric control subjects that was most prominent in boys with MDD. In this independent sample, we focus on gender differences in pituitary volume in a larger sample of pediatric patients with MDD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 35 psychotropic drug-naïve children (15 boys, 20 girls), ages 8-17 years, and 35 case-matched healthy control subjects. RESULTS: The MDD boys had larger PGV (19%) compared with male control subjects. No significant diagnostic group differences in pituitary volume were observed in girls. Healthy boys had significantly smaller PGV (27%) than healthy girls, whereas MDD boys did not differ from girls with MDD. Nonfamilial (without a family history of mood disorder) boys with MDD had significantly larger PGV (35%) than male healthy control subjects and tended to have a larger PGV (27%) than familial (at least one first-degree relative with MDD) boys with MDD. Boys with familial MDD did not differ from control subjects. CONCLUSIONS: These findings provide new evidence of increased pituitary volume in psychotropic-naïve pediatric patients with MDD that seems to be more prominent in male patients with nonfamilial MDD.