Early response and remission as predictors of a good outcome of a major depressive episode at 12-month follow-up: a prospective, longitudinal, observational study.

OBJECTIVE: The goal of treating major depressive disorder (MDD) should be not only achieving remission in a particular episode but also avoiding relapses and attaining long-term recovery. The current study was designed to evaluate whether response and remission achieved within the first 6 weeks of antidepressant treatment are associated with a 12-month good outcome (achieving remission by 6 months and remaining in remission until the end of follow-up).
METHOD: This prospective, longitudinal, multicenter study included adult outpatients who had a DSM-IV diagnosis of MDD, baseline scores ≥ 15 on the 17-item Hamilton Depression Rating Scale (HDRS(17)), Clinical Global Impressions-Severity of Illness scores ≥ 4, and a minimum remission period of 12 weeks between the index episode and the immediately prior episode (or who were in their first MDD episode). The primary efficacy measure was early response (a 50% decrease from baseline in HDRS(17) score by week 6). The secondary efficacy measure was early remission (HDRS(17) score ≤ 7 by week 6).
RESULTS: Among the total of 930 patients included from December 2006 to June 2007, 38.2% showed early response, and 20.5% showed early remission. Of the early responders, 76.1% had a 12-month good outcome as compared to 81.1% of early remitters. Logistic regression showed that factors associated with a good outcome included early response (odds ratio [OR] = 4.14), being employed, and the absence of physical comorbidities. Early remission was also strongly associated with a good outcome (OR = 4.72).
CONCLUSIONS: Either response or remission achieved by week 6 is the strongest prognostic factor for the 12-month good outcome of an episode of MDD. © Copyright 2012 Physicians Postgraduate Press, Inc.