Talk therapy may be a helpful supplemental treatment for people with depression who have not responded to medication, a new study from the United Kingdom suggests.

Researchers found that people with depression who had not improved despite taking antidepressants were three times more likely to experience a reduction in their depression symptoms if talk therapy was added to their treatment regimen compared with those who continued to take only antidepressants.

The study is one of the first large trials to test the effectiveness of talk therapy given in tandem with antidepressants, the researchers said.

Up to two-thirds of people with depression don’t respond fully to antidepressant treatment, and the findings suggest a way to help this group, the researchers said.

“Until now, there was little evidence to help clinicians choose the best next step treatment for those patients whose symptoms do not respond to standard drug treatments,” study researcher Nicola Wiles of the University of Bristol's Centre for Mental Health, Addiction and Suicide Research said in a statement.

The study followed patients for one year. Future studies should examine the effectiveness of this treatment combination over the long term, as patients with depression can relapse after treatment, the researchers said.

In addition, because some patients did not improve substantially when talk therapy was added, further research is needed to find alternative treatments for this group, Wiles added.

The study included about 470 people with depression who had not responded to antidepressants after six weeks of treatment. About half received cognitive behavioral therapy — a type of talk therapy — in addition to their usual antidepressant treatment, and half continued antidepressants without the addition of talk therapy.

After six months, about 46 percent of patients in the talk therapy group experienced at least a 50 percent reduction in their depressive symptoms. By contrast, 22 percent of people in the antidepressant group improved by the same amount. By the 12-month mark, both groups experienced similar rates of improvement.

Often, talk therapy is more difficult to access than medication, the researchers said. And people may not be able to afford the treatment if their health insurance does not cover it. Only about 25 percent of Americans with depression have received talk therapy during the past year, they said.

Pass it on: People with depression who have not responded to antidepressants may benefit from the addition of talk therapy.

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