Successful treatment of major depression: the effects of positive and negative life events on time to remission

Abstract

The relationships of stressful and of positive events to treatment response for depression have typically been studied separately using methods based on the rates of events and ultimate remission status. A novel data-analytic approach was introduced that addresses the limitations of these ad hoc methods and provides more power for detecting effects of life events and other prognostic factors on treatment response. Survival methodology with time-varying covariates was used to delineate the simultaneous but separate effects of positive and negative aspects of life events occurring both prior to and during treatment among patients treated with interpersonal psychotherapy (IPT) alone or IPT followed with adjunctive fluoxetine or imipramine for recurrent unipolar depression. Somewhat surprisingly, stressful events were not significantly related to response time, but neutral events during treatment were related to a prolonged time to remission both alone in univariate analysis and when considered along with other life-event and prognostic covariates in multiple regression analyses. Positive events during treatment did not relate to remission, but those occurring on average 24 weeks prior to remission were associated with more rapid remission in univariate analysis. Other significant correlates of remission included endogeneity, which consistently related to more rapid remission. Overall, these results underscore the importance of studying events, including seemingly neutral and temporally distal experiences, and support the use of the novel methodology in studying the impact of major life events and other prognostic factors on remission of depressive disorder. Copyright © 2000 Whurr Publishers Ltd.