Examining the Process of Change in Cognitive Behaviour Therapy for Treatment Resistant Depression.

Abstract

Objective: The present studies aimed to examine temporal patterns of symptom change over the course of cognitive behavioural therapy (CBT) in individuals with treatment-resistant depression (TRD) and evaluate their relationship to outcomes. They further sought to investigate whether case-conceptualisation competence, client hope and processing were associated with therapeutic change. Method: Participants were 156 individuals with TRD receiving 12-18 sessions of CBT as part of a randomised controlled trial. Depressive severity was assessed at each session. Audio-recordings of therapy sessions proximal to sudden gains and control sessions for 25 sudden gainers and 25 non-sudden gainers were rated for client hope and emotional processing, and therapist competence in case-conceptualisation. Results: The overall shape of change was best described as cubic, with frequent discontinuities in symptom trajectories. Sudden gains were associated with reduced depressive severity and a greater likelihood of remission at 12 months. Sudden gainers demonstrated greater hope than non-sudden gainers and emotional processing increased prior to a gain. Therapists showed greater competence in case-conceptualisation with sudden gainers. Conclusion: The present study describes a non-linear shape of change in TRD and extends the phenomenon of sudden gains to this population. It suggests that the combination of hope for change with supported efforts to process and make meaning of experiences may predispose individuals favourably towards experiencing sudden gains in therapy.