Severity and the Treatment of Depression: A Review of Two Controversies

Severity is an important consideration in treatment decision-making for depression. Two controversies in the treatment of depression are related to the issue of severity. First, are antidepressants only effective for severely depressed patients? Second, should the severity of depression be used as the basis for recommending medication or psychotherapy as first-line treatment? More specifically, should patients with severe depression preferentially be treated with medication? A related question is whether psychotherapy is beneficial for severely depressed patients. Some controversial articles sparked coverage in the popular press related to these questions and stimulated subsequent research on the impact of depression severity on treatment efficacy. The results of three recent large pooled analyses of patient level data indicate that the efficacy of antidepressants is not limited to the narrow band of patients who score highest on symptom severity scales. A meta-analysis of 132 controlled psychotherapy studies of more than 10,000 patients found that greater mean baseline symptom severity did not predict poorer response. A pooled analysis of individual patient data from 16 studies comparing antidepressants and cognitive behavior therapy found that severity was not associated with differential treatment outcome. These results are discussed in the context of recommendations in official treatment guidelines.