Long-term Effects of Preventive Cognitive Therapy in Recurrent Depression: a 5.5-year Follow-up Study

Objective: Major depressive disorder (MDD) was projected to rank second on a list of 15 major diseases in terms of burden in 2030. A crucial part of the treatment of depression is the prevention of relapse/recurrence in high-risk groups, ie, recurrently depressed patients. The long-term preventive effects of group cognitive therapy (CT) in preventing relapse/recurrence in recurrent depression are not known. This article reports on the long-term (5.5-year) outcome of a randomized controlled trial to prevent relapse/recurrence in patients with recurrent depression. We specifically evaluated the long-term effects of CT in relation to the number of previous episodes experienced.

Method: From February through September 2000, patients with recurrent depression (DSM-IV-diagnosed) who were in remission (N = 172) were recruited from primary and specialty care facilities. They were randomly assigned to treatment as usual (TAU) versus TAU augmented with brief group CT. The primary outcome measure was time to relapse/recurrence, which was assessed over 5.5 years.

Results: Over 5.5 years, augmenting TAU with CT resulted in a significant protective effect (P = .003), which intensified with the number of previous depressive episodes experienced. For patients with 4 or more previous episodes (52% of the sample), CT significantly reduced cumulative relapse/recurrence from 95% to 75% (medium effect size).

Conclusions: Our findings indicate that brief CT, started after remission from a depressive episode on diverse types of treatment in patients with multiple prior episodes, has long-term preventive effects for at least 5.5 years. Implementation of brief relapse prevention CT should be considered in the continued care of patients with recurrent depression.

Trial Registration: ccmo-online.nl Identifier: NTR454.