Factors associated with the development of substance use disorder in depressed adolescents.

OBJECTIVE: To document rates of substance use disorders (SUD) in adolescents with unipolar major depressive disorder and to examine demographic, clinical, and biological factors associated with the development of SUD. METHOD: Twenty-eight adolescents with unipolar major depression and no SUD history and 35 group-matched normal controls who participated in a cross-sectional sleep polysomnography and neuroendocrine study were reassessed clinically 7 years later. RESULTS: The risk for SUD was high in both groups (34.6% in the depressed group and 24.2% in the controls). Depressed adolescents had earlier onset of SUD than controls. Depressed adolescents who developed SUD had more significant psychosocial impairment than depressed adolescents who did not develop SUD. More anxiety traits and elevated cortisol secretion near sleep onset were associated with SUD in depressed teenagers, whereas less emotional responsiveness to exciting stimuli and higher density of eye movements during REM sleep were related to depression without SUD. CONCLUSIONS: Depressed adolescents who have anxiety traits and whose hypothalamic-pituitary-adrenal axis is active when the system is normally quiescent may be at risk for developing SUD. Co-occurrence of depression and SUD is associated with serious psychosocial morbidity. Identification of risk factors for SUD in depressed teenagers may be helpful in developing more effective treatment and prevention programs.