Predictors of the first onset of a major depressive episode and changes in depressive symptoms across adolescence: stress and negative cognitions.

This 6-year longitudinal study examined stressors (e.g., interpersonal, achievement), negative cognitions (self-worth, attributions), and their interactions in the prediction of (a) the first onset of a major depressive episode (MDE), and (b) changes in depressive symptoms in adolescents who varied in risk for depression. The sample included 240 adolescents who were first evaluated in Grade 6 (M = 11.86 years old; SD = 0.57; 54.2% female) and then again annually through Grade 12. Stressful life events and depressive diagnoses were assessed with interviews; negative cognitions and depressive symptoms were assessed with self-report questionnaires. Discrete time hazard modeling revealed a significant interaction between interpersonal stressors and negative cognitions, indicating that first onset of an MDE was predicted by high negative cognitions in the context of low interpersonal stress, and by high levels of interpersonal stressors at both high and low levels of negative cognitions. Analyses of achievement stressors indicated significant main effects of stress, negative cognitions, and risk in the prediction of an MDE, but no interactions. With regard to the prediction of depressive symptoms, multilevel modeling revealed a significant interaction between interpersonal stressors and negative cognitions such that among adolescents with more negative cognitions, higher levels of interpersonal stress predicted higher levels of depressive symptoms, whereas at low levels of negative cognitions, the relation between interpersonal stressors and depression was not significant. Risk (i.e., maternal depression history) and sex did not further moderate these interactions. Implications for intervention are discussed.