TUESDAY, May 31 (HealthDay News) -- As a component of depression treatment, psychotherapy not only reduces anxiety, but also improves patients' stress hormone levels, new research shows.

The study, published in the current issue of Psychotherapy and Psychosomatics, found that when pharmacotherapy is combined with psychotherapy in treating depressed patients, there is an improvement in their levels of the stress hormone cortisol.

Researchers examined 63 people diagnosed with major depressive disorder. Participants were divided into two groups: 29 received combined therapy, which included psychotherapy and pharmacotherapy, and 34 had monotherapy, which included only pharmacotherapy. The patients' depressive symptoms were tested at regular daily intervals over the course of eight months.

The study found that although decreases in symptoms were similar between both groups, by the eighth month, reductions in anxiety were greater among those in the combined therapy than in the patients who underwent monotherapy. Moreover, a steeper daytime cortisol pattern was more likely among those who had the combined therapy, compared to those who were treated with drugs alone.

Researchers concluded that the improved outcomes of the combined therapy group suggests the addition of psychotherapy helped reduce anxiety and produced long-term positive effects on stress hormone levels.

More information

The U.S. National Institutes of Health has more information on cortisol.