Physical symptoms, many of which are unexplained, are common in depressed patients and often are indicators of depression. Although the presence of unexplained symptoms and multiple somatic complaints alerts physicians to the possibility of an affective disorder, little is known about whether treating depression reduces physical symptoms. In the ARTIST (A Randomized Trial Investigating SSRI Treatment) trial, patients were randomized to receive three selective serotonin reuptake inhibitors (SSRIs) and periodically assessed for depressive and physical symptoms over nine months. In addition, some domains of the health-related quality of life (HRQL) were assessed.

Depressed patients drawn from 37 practices who were about to start antidepressant therapy were randomized to receive paroxetine, fluoxetine, or sertraline. Telephone interviews were conducted at baseline and at four intervals thereafter. Questionnaires and checklists were administered to assess depression, physical symptoms, and quality of life. A statistical analysis determined whether there was any correlation between symptom improvement and improvement in depression.

Of 601 randomized patients, 573 completed the baseline telephone assessment, with 79 percent of enrollees completing the nine-month study. Of the 14 physical symptoms assessed, the most common ones were fatigue and sleep problems, headaches, nausea, and back pain. Almost all symptoms were present in up to one half of patients. Few patients developed new symptoms in the course of the study.

All physical symptoms improved substantially in the first month of antidepressant use but plateaued during the course of the study. In contrast, mood and well-being continued to rise, albeit gradually, after a first month of steep improvement. However, when the relationship of response to antidepressants and physical symptoms was analyzed, it was found that responders had a greater decrease in physical symptoms than nonresponders as measured at months 1 and 3. Impact on quality-of-life measures varied. Physical symptoms had the greatest effect on such domains as pain, health, and physical functioning, whereas depression had the greatest effect on mental health and social domains.

In this study, as in previous studies, physical symptoms were common among depressed patients. Even though depression initially improved rapidly and continued to improve gradually over nine months, physical symptom improvement plateaued after an initial change for the better. Pain symptoms improved least. These findings suggest that physical symptoms are at least somewhat separate from psychologic symptoms. Targeting these symptoms independently may be helpful, although more studies are needed to determine which interventions are effective.