The course of depression in individuals at high and low cognitive risk for depression: a prospective study.

BACKGROUND Negative cognitive styles have been shown to prospectively predict depression onset and recurrence. Research has also begun to suggest that cognitive styles may be associated with the course of depression as well. This study examined whether cognitive risk for depression onset also predicts the course of depression in a prospective design. METHODS One hundred fifty-nine initially nondepressed participants from the Temple-Wisconsin Cognitive Vulnerability to Depression Project who experienced a depressive episode while in the study were followed prospectively for 2.5 years. Four indicators of the course of depression were assessed from diagnostic interviews and questionnaires administered every 6 weeks: the number, severity and duration of episodes and the chronicity of the depression experienced. RESULTS Cognitive high-risk participants experienced more episodes of depression, more severe episodes, and more chronic courses than low-risk participants. There were no risk group differences observed for the duration of episodes. LIMITATIONS This study's sample was chosen to include individuals with high and low cognitive vulnerability to depression, potentially limiting the generalizability of the findings to other individuals. Also, the study included some participants with a past history of depression. CONCLUSIONS Negative cognitive styles predict a worse course of depression as well as rendering an individual prone to depression onset. This highlights that the cognitive factors impacting depression's course overlap, at least partly, with those that initiate depression. Thus, knowledge of a depressed individual's cognitive styles could aid in prognosis and treatment planning.