Mindfulness-based cognitive therapy (MBCT), derived from mindfulness-based stress reduction, is a group-based skills training programme designed to enable patients to learn skills that prevent the recurrence of depression. The MBCT intervention evaluated in this study consisted of an 8-week class that included support to taper or discontinue maintenance antidepressant medication.
In the group randomised to MBCT, patients and their GPs were given guidelines on typical tapering or discontinuation regimens. These recommended that patients began a tapering regimen after 6 weeks of treatment; however, GPs and patients determined the individual regimen. Of those who completed at least four sessions of MBCT (83%), 17% reduced their dose and 71% discontinued their antidepressant. Those randomised to continued maintenance antidepressants received support from their GPs to continue treatment for the 2-year follow-up; however, patients remained in the trial whatever treatment choices they made.
The primary outcome was time to relapse or recurrence of depression (defined as an episode meeting DSM-IV criteria for a major depressive episode) - there was no evidence of a reduction in the MBCT group compared with the maintenance antidepressant group. A total of 94 (44%) of those randomised to MBCT relapsed compared with 100 (47%) of the maintenance antidepressants group (HR 0.89, 95% CI 0.67-1.18, p=0.43).
A cost analysis showed that total health and social care costs did not differ significantly between the MBCT and the maintenance antidepressants group (mean difference £124, 95% CI −749.98 to 972.57, p=0.80). Exploration of statistical uncertainty suggests that the probability of MBCT being more cost effective than maintenance antidepressants does not rise above 52%.
The authors discuss a number of limitations to their study. Due to the study sample, the results are only generalisable to people at high risk of depressive relapse or recurrence who are already taking maintenance antidepressants and who are in equipoise about the type of preventive treatment. There was no usual care or an attention control group, and so any effects of MBCT cannot be inferred to be specific to MBCT. Not all of the MBCT group discontinued antidepressants and therefore although pragmatic, the trial was not fully controlled.
They conclude on the basis of their research and previous studies that MBCT might confer ongoing protection for patients who would like an alternative to maintenance antidepressant medication. The author of a related comment questions whether there are specific effects of MBCT that confer a decreased risk of relapse or whether any structured group psychotherapy would produce similar results.