Psychotherapy for Medically Unexplained Pain: A Randomized Clinical Trial Comparing Intensive Short-Term Dynamic Psychotherapy and Cognitive-Behavior Therapy

Abstract

The efficacy of intensive short-term dynamic psychotherapy (ISTDP) for medically unexplained pain remains open to debate because of a paucity of high-quality studies. This study sought to evaluate ISTDP as a treatment for medically unexplained pain in outpatients by comparing it with the established evidence-based cognitive-behavioral therapy (CBT) in a randomized clinical trial. A total of 341 adults with medically unexplained pain were randomly assigned to 16 sessions of individual manualized CBT (N = 164) or ISTDP (N = 177). The groups were assessed at baseline, after 16 weeks of treatment, and at the 3-month follow-up. The primary outcome was perceived pain assessed using the numerical pain rating scale. The secondary outcomes were psychologic distress, depression, and cognitive variables. The cognitive variables included self-efficacy, catastrophizing, and coping strategies. In the intention-to-treat analysis, the ISTDP and CBT groups both showed improvement in the primary outcome after treatment. Pain symptoms in both conditions were significantly reduced. Both ISTDP and CBT groups demonstrated reductions in psychologic distress, depression and catastrophic thinking, and also increases in the use of relaxation as a coping strategy. The CBT group showed an improvement in self-efficacy that was not obtained in the ISTDP group. However, significant differences were not observed in the primary and secondary outcomes at the 3-month follow-up compared with posttreatment. Overall, both treatments were equally effective at the 3-month follow-up. Our results suggest that ISTDP may provide an effective alternative therapy for medically unexplained somatic symptoms of pain.