Extreme response style in recurrent and chronically depressed patients: change with antidepressant administration and stability during continuation treatment.

The authors examined extreme response style in recurrently and chronically depressed patients, assessing its role in therapeutic outcome. During the acute phase, outpatients with major depressive disorder (N = 384) were treated with fluoxetine for 8 weeks. Remitted patients (n = 132) entered a continuation phase during which their fluoxetine dose increased and they were randomly assigned to treatment with or without cognitive-behavioral therapy (CBT). Results showed a predictive relationship between extreme response style and clinical outcome. Patients in the medication-only group showed a significant increase in the frequency of extreme responses, whereas patients receiving CBT showed no significant change. These results are consistent with recent findings suggesting that metacognitive factors may be as important as changes in thought content when treating depression.