Cognitive behavior therapy and relapse of nonbipolar depression: parallels with pharmacotherapy.

The risk of relapse was studied in 44 major depressives following successful acute treatment with cognitive behavior therapy (CBT). Patients entered a 1-year prospective followup with independent clinical assessments at 1, 3, 6, 9, and 12 months. Of these patients, 15 (34%) relapsed; correlates included marital status, recurrent subtype, higher initial and residual ratings of depressive severity, and slower response to therapy. Both married status (p = .008) and fully recovered status (p = .02) were significantly and independently related to decreased risk of relapse using the Cox proportional hazard method. These findings provide further documentation of a relationship between residual symptomatology and relapse after cessation of active treatment and closely parallel findings pertaining to risk of relapse after acute antidepressant pharmacotherapy of unipolar depression. As in pharmacotherapy, a longer period of continuation treatment may be indicated for patients at risk for relapse after an initial course of time-limited therapy with CBT.