Wienicke, F.J., Beutel, M.E., Zwerenz, R. et al. (2023). Efficacy and moderators of short-term psychodynamic psychotherapy for depression: A systematic review and meta-analysis of individual participant data, Clinical Psychology Review.
Depression affects 264 million adults worldwide making it one of the most prevalent mental health conditions. Depression affects quality of life, health care costs, and mortality making it a leading cause of disability in the world. Previous meta-analyses have looked at psychological treatments for depression and found CBT, short term psychodynamic psychotherapy (STPP), interpersonal psychotherapy (IPT), and others are effective in reducing depressive symptoms among adult patients. STPP, for example, works by focusing on the underlying personality factors of the patient (defense mechanisms, emotion regulation, interpersonal style, self-concept, attachment) that may lead to depressive experiences. There are very few studies that look specifically at what patient characteristics are associated with better outcomes for a specific type of psychotherapy. The challenge with such patient level analyses is that most researchers report aggregated individual patient data at the study level thus possibly obscuring important variability among patients. In this meta-analysis, Wienicke and colleagues identified 13 studies of STPP compared to a control group. The authors were able to get 11 of the study authors to provide individual patient data of 771 participants. This allowed Wienicke and colleagues to do a meta-analysis of individual patient data. At post-treatment, STPP was significantly more efficacious than control conditions on measures of depression (d = -0.62, 95%CI [-0.76, - 0.47], p <.001), anxiety (d = -0.29, 95%CI [-0.45, -0.12], p <.001), general psychopathology (d = -0.38, 95%CI [-0.59, -0.17], p <.001), and quality of life (d = 0.44, 95%CI [0.23, 0.64], p <.001). At follow-up, STPP was again superior to control conditions on depression outcomes (d = -0.21, 95%CI [-0.38, -0.05], p = .011), but not more efficacious on other outcomes. When the authors looked at individual patient characteristics related to outcomes, they found that length of the current depressive episode was found to moderate post-treatment depression levels, such that STPP was more efficacious for participants reporting longer rather than shorter episode durations (d = -0.006, 95%CI [-0.01, -0.001], p = .002).
Like what was reported in previous meta-analyses, STPP was efficacious to reduce depressive symptoms in the shorter and longer term. Patients with a longer duration or chronicity of depressive symptoms experienced the most benefit from STPP. It is likely that individuals with longer episode durations have depressive symptoms that are more influenced by their underlying personality vulnerabilities resulting in more complex working alliances and transference feelings with therapists. Training in psychodynamic principles of treatment may allow therapists to identify and work with these therapeutic relational aspects if necessary.