The primary purpose of this study is to investigate neural mechanisms and predictors of treatment outcome in Mindfulness-Based Cognitive Therapy (MBCT) for recurrent Major Depressive Disorder.

AIM AND HYPOTHESES

The primary aim is to investigate treatment mechanisms of MBCT and markers of relapse risk.

Controlled design:

First, we aim to first investigate the effect of treatment on clinical outcomes in the controlled design post treatment and at 3 months follow up. Second, we will run mediation analyses of hypothesized mechanisms (increased mindfulness skills, decentering, interoceptive and decreased rumination, and change in neural connectivity in a priori networks), and finally check for moderating influences of vulnerability markers (childhood trauma, no. episodes of depression and residual symptoms).

Prospective design:

We aim to investigate predictors of relapse risk at 12 month follow treatment using i) baseline markers and ii) mechanism outcomes that change significantly due to treatment, and iii) check for moderating influences of vulnerability markers

Inclusion Criteria:

1. Age above 18 years
2. Meeting DSM-IV criteria for a history of recurrent Major Depressive Disorder (MDD) with or without a current episode of depression
3. Recurrent MDD evaluated a being the primary disorder.
4. Danish literacy

Exclusion Criteria:

1. A history of schizophrenia, schizoaffective disorder, bipolar disorder, current severe substance abuse, organic mental disorder, current/past psychosis, pervasive developmental delay, persistent antisocial behaviour, persistent self-injury requiring clinical management/therapy
2. Formal concurrent psychotherapy
3. Previous Mindfulness-Based Cognitive Therapy/Mindfulness-Based Stress Reduction
4. Anti-psychotic medication and benzodiazepines
5. Standard exclusion criteria for undergoing magnetic resonance imaging (MRI) procedures for research purposes, i.e., claustrophobia, pregnancy, cardiac pacemaker, prosthetic heart valve, neurostimulator, implanted pumps, cochlear implants, non-MR-compatible implants or devices.

Participants are masked at baseline assessment to treatment allocation. Outcome assessors are masked to treatment allocation.