Effectiveness of group cognitive behavioral therapy for somatoform pain disorder patients in Japan: A preliminary non-case-control study.

Aims Somatoform pain disorder is associated with psychosocial dysfunction, and psychotherapies, such as cognitive behavioral therapy (CBT), are thought to provide useful interventions to address such dysfunction as well as the pain itself. However, little is known about whether CBT for somatoform pain disorder is effective, including the long-term course of the illness, in non-Western populations. We therefore tailored such a program based on an existing CBT protocol and examined its effectiveness in Japan. Methods Thirty-four Japanese participants (22 women; mean age = 52.5 years) enrolled in a weekly 12-session group treatment, with 32 completing both wait-list and treatment conditions. The primary outcome measure was pain intensity. Secondary outcome measures included pain characteristics, as measured by pain catastrophizing and psychometric evaluations, including depression, anxiety, and quality of life. The patients were followed up for 12 months after treatment. Results We found that pain intensity, anxiety, depressive symptoms, and social functioning all significantly improved after treatment compared with the wait-list period, and the improvements in pain intensity, depressive symptoms, and social functioning were sustained at 12 months following the completion of CBT. There were strong positive correlations (P < 0.01) among pre- and post-treatment changes in the affective dimension of pain, depression, anxiety, and pain catastrophizing. Conclusions These results show that the present CBT program was effective for Japanese patients with somatoform pain disorder and that gains were maintained over the long term. More work is needed to further clarify the effects of CBT interventions on somatoform symptoms, particularly in Japan.