Treatment-resistant depression: prevalence, risk factors, and treatment strategies

Full symptomatic remission is the optimal outcome for patients with major depression. Unfortunately, initial antidepressant efficacy is limited to partial response for many patients. Incomplete remission of depressive symptoms is associated with increased risk of relapse, decreased functioning in work and social settings, and increased risk of suicide. Factors that increase the likelihood of treatment resistance include chronicity, severe symptomatology, and comorbid illnesses. Strategies to manage patients who do not respond to an initial course of antidepressant medication include optimizing the dose, switching antidepressants, or adding adjunctive treatment (ie, psychotherapy or a second medication). Augmentation may be the preferred strategy for improving response if tolerability to the original agent is acceptable and the initial medication has had some beneficial effects. Tracking patients' depressive symptoms with standardized measurement tools during the course of treatment is necessary for identifying incomplete remission and providing appropriate treatment modification.