Cognitive behavioural therapy (CBT) is most effective in patients who have had four or more prior episodes of depression, according to new research from The Netherlands.

The study, published in the December issue of the British Journal of Psychiatry, suggests GPs could use the number of prior episodes to determine which patients are likely to benefit most from therapy and prescribe treatment accordingly.

Researchers in The Netherlands studied 208 patients between the ages of 18 and 70 who were receiving treatment for depression from their GP. Some of the participants were given psychoeducation, others were given CBT plus psychoeducation, and the rest carried on with their usual GP treatment.

The psychoeducation programme consisted of three face-to-face sessions and short 3-monthly telephone contacts after that. CBT plus psychoeducation consisted of 10-12 sessions with a psychotherapist, followed by the psychoeducational programme. All the participants were regularly assessed over a period of two years to determine the severity of their depression.

For patients who had three or fewer prior episodes of depression, the three types of treatment performed equally well. In other words, psychoeducation and CBT plus psychoeducation did not have any significant effect on their depression over the two-year period.

However, patients who had had four or more prior episodes of depression did respond positively to CBT plus psychoeducation.

The researchers said: "We found that in patients with three or fewer prior episodes the three treatments perform equally well, whereas in patients with four or more episodes, CBT plus psychoeducation performs clinically better than usual care. This effect is assumed to be attributable to the CBT component of CBT plus psychoeducation, since psychoeducation did not differ from usual care (although a favourable interaction between psychoeducation and CBT cannot be ruled out completely."

The researchers continued: "Therefore, GPs may consider the number of previous depressive episodes, which is a strong predictor of an unfavourable course of depression, as a treatment indicator in order to optimise allocation of scarce treatment capacity. Patients with few prior episodes show no additional benefit with CBT, whereas for patients with multiple prior episodes, GPs may advise CBT in addition to usual care."

Reference:
"Cognitive-behavioural therapy v. usual care in recurrent depression"
Conradi HJ, de Jonge P and Ormel J (2008)
British Journal of Psychiatry, 193: 505-506

British Journal of Psychiatry

Royal College of Psychiatrists