Cognitive and emotional variables predicting treatment outcome of cognitive behavior therapies for patients with medically unexplained symptoms: A meta-analysis

Objective: Cognitive behavior therapy (CBT) is the best-evaluated psychological approach to treat patients with medically unexplained symptoms (MUS). We still need a better understanding of what characterizes patients with MUS who benefit more or less from CBT. This systematic review aimed to identify patients' cognitive-emotional characteristics predicting the outcome of CBT for MUS. Methods: A systematic literature search (PubMed, PsycINFO, Web of Science) revealed 37 eligible studies, 23 of these provided data for meta-analyses. Mean correlation coefficients between predictor variables and the outcomes (symptom intensity, physical or social-emotional functioning) were calculated using a random-effects model. Differences between syndromes of MUS were investigated with moderator analyses. Results: Meta-analyses showed that patients with a comorbid mood disorder (r = 0.32, p < .01) or anxiety disorder (r = 0.18, p < .01), symptom catastrophizing and worries (r = 0.34, p < .01), tendencies of somatosensory amplification (r = 0.46, p = .04), and low symptom acceptance or self-efficacy (r = 0.25, p < .01) have a less favorable CBT outcome. Moderator analyses revealed that these associations between predictors and treatment outcome are pronounced in patients with chronic fatigue syndrome and irritable bowel syndrome. Conclusions: Our results show that pre-treatment differences in patients' cognitive-emotional characteristics predict patients' outcome in CBT. Patient-tailored CBT could be a promising approach to address MUS patients' widely varying needs more effectively.

Automated summary

Cognitive behavior therapy is effective for treating patients with medically unexplained symptoms, but those with comorbid mood disorders, anxiety disorders, symptom catastrophizing, somatosensory amplification tendencies, and low self-efficacy have a less favorable outcome. These associations are more pronounced in patients with chronic fatigue syndrome and irritable bowel syndrome.