Long-term effectiveness of cognitive therapy in major depressive disorder

Cognitive therapy of depression, based on the cognitive theory of depression, is an established treatment for major depressive disorder. Although few clinicians expect acute treatment of depression with antidepressant medication to prevent long-term relapse of the illness, some practitioners of cognitive therapy report long-term effectiveness in preventing relapse after short-term treatment. We set out to reanalyze follow-up studies in the literature, using intent-to-treat principles to assess the long-term effects of acute treatment with cognitive therapy. From an initial reference list of 97 citations that met our search criteria (controlled clinical trials of cognitive therapy in depression with follow-up), we found five trials that met our inclusion criteria. This report reviews and reanalyzes these five trials, published between 1981 and 1992, which compare cognitive therapy and tricyclic antidepressant therapy. Overall, the evidence favors a longer-term effect for cognitive therapy over tricyclic antidepressants alone.