A Meta-Analysis of Interpersonal and Psychodynamic Psychotherapies for Posttraumatic Stress Disorder

Established trauma-focused cognitive-behavioral therapies for posttraumatic stress disorder (PTSD) have remission rates of approximately 30%-40%. Alternatively, interpersonal psychotherapy (IPT) and psychodynamic psychotherapy (PDT) focus on disrupted attachment, mentalization, and social connection in PTSD and may help some patients. The authors conducted a meta-analysis on these interpersonal and affect-oriented approaches to treating PTSD.

Building on a prior meta-analysis, the authors searched for randomized controlled trials (RCTs) comparing IPT or PDT with other established PTSD treatments or control conditions for adults diagnosed as having PTSD. Random-effects meta-analyses were conducted to assess outcome effect sizes and dropout rates. RCTs were rated via the Randomized Controlled Trial Psychotherapy Quality Rating Scale.

Ten RCTs (eight of IPT) comparing IPT or PDT with control (k=7) or active treatment (k=4) conditions were identified, nine of which were of adequate quality. IPT (k=5) and PDT (k=2), when analyzed together, were superior to control conditions overall (g=-1.14, p=0.011 [as was IPT alone: g=-0.88, p=0.034]) and to waitlist (g=-1.49) and treatment-as-usual (g=-0.70) groups. Effect sizes, however, may have been inflated by outliers or publication bias. IPT (k=3) and PDT (k=1), when analyzed together, were equally efficacious compared with other active PTSD treatments (primarily exposure-based psychotherapies), as was IPT alone, and had lower dropout rates (relative risk=0.63, p=0.049 for IPT and PDT analyzed together; relative risk=0.61, p=0.098 for IPT alone).

Affect-focused therapies hold promise in the treatment of PTSD. IPT has demonstrated efficacy in multiple trials, whereas the evidence base for PDT is sparse.