Emotion Regulation and Attachment as Mechanisms of Change in Schema Therapy and Cognitive Behaviour Therapy for Depression

Background. Psychotherapy is an efficacious treatment for depression; however, the rates of non-response and relapse remain unsatisfactory. In this study, we examined attachment and emotion regulation as two relevant mechanisms of change to improve treatment efficacy. We tested the hypotheses that schema therapy and cognitive behavior therapy have differential effects on these mechanisms, that changes in the mechanisms precede depressive symptoms and that the effects of schema therapy and cognitive behavior therapy on depressive symptoms are mediated by the mechanisms. Methods. We conducted a secondary analysis of data from a randomized controlled trial with 198 depressed patients treated with comprehensive psychiatric care and either schema therapy or cognitive behavior therapy for 7 weeks in an inpatient or day clinic setting. We calculated random intercept cross-lagged panel models (RI-CLPMs) within a Bayesian statistical framework separately for each of the mechanisms of change (anxious and avoidant attachment, emotion suppression and cognitive reappraisal). Results. The data did not support the hypotheses, but consistently supported the null hypotheses that schema therapy and cognitive behavior therapy do not have differential effects on the mechanisms of change, that the mechanisms of change do not predict subsequent symptom change, and that the mechanisms of change do not mediate treatment effects on depressive symptoms. Conclusions. Our analyses found that emotion suppression and cognitive reappraisal as emotion regulation strategies and avoidant and anxious attachment do not play a relevant role as mechanisms of change in psychotherapy for patients with depression in an inpatient or dayclinic psychiatric setting.