ADOLESCENT DEPRESSION: NEUROENDOCRINOLOGIC FEATURES

Abstract

This study was undertaken to determine whether a relationship might be found between the existence of depressive illness in adolescents and alterations in the functional status of the hypothalamic-pituitary-thyroid axis, and was part of a larger study intended to describe diagnostic, biologic, and cognitive features of adolescent depression. Eighteen inpatients were included after being diagnosed with severe depression as determined by two interviewers using two depression inventories and applying DSM III criteria. Thirteen females and five males ranged in age from 14-19 years (mean 15.6 yrs). Each patient was subjected to an overnight dexamethasone suppression test (DST) using a dose of 1 mg and TRH infusion using a dose of 500 mcg. Abnormal responses were defined as any one of the three cortisol levels measured > 5 mcg/dl or a rise in TSH < 7 mcIU/ml. Seven patients showed abnormal responses; two blunted TSH responses (both males), two non-suppression on DST (both females) and both tests abnormal in two males and one female. Baseline TSHs did not differ in the two groups. Clinical features associated with depression did not distinguish between the two groups. In this series, blunted TRH response occurred with frequency equal to non-suppression on the DST.