Major Depressive Disorder, Recurrent, in Remission

Objectives: To evaluate the clinical- and cost-effectiveness of two delivery formats of mindfulness-based cognitive therapy (MBCT) - (i) MBCT delivered through eight videoconference group sessions (group MBCT), and (ii) MBCT delivered through a self-help manual plus three low-intensity videoconference group support sessions (supported MBCT self-help) - when added to treatment as usual (TAU; mental health outpatient care), compared with TAU alone, in patients with recurrent depression in partial remission. We will identify potential predictors and moderators of response and examine psychological mechanisms of change. Study design: Multicentre randomised controlled trial, with pre-post, 6- and 12-months follow-ups. Centres: Parc Sanitari Sant Joan de Déu (St. Boi de Llobregat), Hospital Universitario Miguel Servet (Zaragoza), and Hospital del Mar (Barcelona). Participants: Adult patients (n=315) with recurrent depression in partial remission will be randomly assigned to group MBCT, supported MBCT self-help, or TAU. Primary outcome: time from randomisation to depressive relapse/recurrence at 12-month follow-up (DSM-5). Secondary outcomes: residual symptoms, well-being, quality of life, costs, and quality-adjusted life years. Process measures: rumination, mindfulness, decentering, affectivity, and self-compassion. Main statistical analyses: Hazard ratios will be calculated using survival analysis. Secondary outcomes, predictors, and moderators will be tested using regression-based approaches. Incremental cost-effectiveness ratios from healthcare system and societal perspectives will be estimated, alongside mediation analyses. Expectations and acceptability will be evaluated using qualitative methods. Conclusions: This study will inform the implementation of two accessible MBCT formats in Spain for preventing depressive relapse/recurrence. The use of different delivery formats will provide information on effectiveness, scalability, and value for money.

Antidepressants are widely used as first-line treatments for major depressive disorder (MDD). Clinical guidelines recommend 6-24 months of "maintenance" antidepressant treatment, after patients achieve symptom remission, to prevent relapse but many people stop antidepressants too soon relapse into another depressive episode. We will test non-medication treatments, negative ion therapy and light therapy, to see they can substitute for antidepressants to prevent relapse. This is a "feasibility" study to see if participants use study treatments properly, before doing a larger, definitive trial. In this 28-week study, 100 participants with MDD who are in remission with antidepressants will be treated with light therapy or negative ion therapy (with half of devices active and half inactive) while slowly discontinuing the antidepressant, and monitored for relapse.