Effects of mindfulness-based cognitive therapy on self-reported suicidal ideation: results from a randomised controlled trial in patients with residual depressive symptoms.

INTRODUCTION The aim of the present study was to investigate the effects of mindfulness-based cognitive therapy (MBCT) on suicidal ideation in an open-label randomised controlled trial of patients with residual depressive symptoms. Furthermore, this study aimed at examining whether an effect of MBCT on suicidal ideation was dependent on a reduction in depression severity, worry and rumination, or an increase in mindfulness. METHODS One hundred and thirty participants were randomised to a treatment arm (treatment as usual plus MBCT) or a wait list arm. Change in depression, change in worry, change in rumination and change in mindfulness were entered as covariates in a repeated measures ANOVA in order to assess to what degree MBCT-induced changes in suicidal ideation were independent from changes in these parameters. RESULTS There was a significant group×time (pre vs. post) interaction on suicidal ideation indicating a significant reduction of suicidal ideation in the MBCT group, but not in the control group. The interaction remained significant after addition of the above covariates. Change in worry was the only covariate associated with change in suicidal ideation, causing a moderate reduction in the interaction effect size. CONCLUSIONS The results suggest that MBCT may affect suicidal ideation in patients with residual depressive symptoms and that this effect may be mediated, in part, by participants' enhanced capacity to distance themselves from worrying thoughts.