Psychosocial and clinical predictors of response to pharmacotherapy for depression.

A more complete understanding of the psychosocial and clinical predictors of response to pharmacotherapy would be of great value to both patients and physicians. Most demographic and clinical factors have not been found to be useful predictors of response. Although comorbid illness affects quality of life, there is confounding evidence about its importance when predicting response to antidepressant therapy. Some social support factors appear to be positive predictors of outcome in most trials. There is evidence to suggest that comorbid anxiety disorders and panic-agoraphobic spectrum symptoms are negative predictors of response to treatment. Substance abuse has been associated with a poorer response to antidepressant therapy, and recovery from substance abuse problems has been shown to be poorer among patients with comorbid depression. Assessment of personality dimensions may be a useful predictor of clinical course and outcome, but personality disorders present a complicated picture, with significant interaction among variables. A number of variables are significantly related to clinical course, but few factors have been clearly linked to treatment response. The challenge is to determine if any of these factors are indeed independent predictors of response and whether it is possible to match choice of antidepressant therapy and patient type.