"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", says Nicola Wiles from the University of Bristol who led the research.
Wiles and colleagues recruited 469 adults (aged 18 years) who had not responded to at least 6 weeks of treatment with an antidepressant from 73 general practices across the UK. Participants were randomised to either continue with usual care provided by their general practitioner, which included continuing on antidepressant medication (235 patients), or to receive CBT in addition to usual care (234 patients) and were followed up for 12 months.
After 6 months, 46% of participants who received CBT in addition to usual care had improved (reporting at least a 50% reduction in depressive symptoms) compared to 22% of those who continued with treatment as usual. Individuals in the intervention group were also more likely to experience remission and have fewer symptoms of anxiety. Similar beneficial effects were reported at 12 months.
In the UK, approximately 3% of adults report depression in the previous week, while every year in the USA about 7% of adults suffer from this debilitating condition. Depression is predicted to become the leading cause of disability in high income countries by 2030.
According to Wiles, "In many countries access to CBT is limited to those who can afford it. Even in the UK where there has been substantial investment in psychological services, many people who have not responded to antidepressants still do not receive more intensive psychological therapies such as CBT that take 12 to 18 sessions. In the USA, only about a quarter of people with depression have received any form of psychological therapy in the last 12 months."
Writing in a linked Comment, Michael Otto from Boston University, USA, and Stephen Wisniewski from the University of Pittsburgh, USA, note that the timing of this study is particularly fortuitous because of the £500 million that the UK Government has recently allocated to the Improving Access To Psychological Therapies (IAPT) scheme to increase access to treatments such as CBT for depression. They write: "[These findings] add to the already impressive efficacy for CBT as assessed for other stages of treatment …If the broader IAPT vision is realised, it has the potential to serve as a model for depression treatment for other nations."