Abstract: Twenty-one studies were eligible for inclusion (1745 participants; 19 in adults, 2 in adolescents). Most studies used multimodular approaches. The risk of bias was high for all studies. In adults, psychotherapy had no effect on quality of life at around 12 months (3 studies, 235 patients, SMD -0.07; 95% CI -0.33 to 0.19), emotional status (depression, 4 studies, 266 patients, SMD 0.03; 95% CI -0.22 to 0.27) or proportion of patients not in remission (5 studies, 287 patients, OR 0.85; 95% CI 0.48 to 1.48). Results were similar at 3 to 8 months. There was no evidence for statistical heterogeneity or subgroup effects based on type of disease or intensity of the therapy. In adolescents, there were positive short term effects of psychotherapy on most outcomes assessed including quality of life (2 studies, 71 patients, SMD 0.70; 95% CI 0.21 to 1.18) and depression (1 study, 41 patients, SMD -0.62; 95% CI -1.25 to 0.01). Educational interventions had no effect on quality of life at 12 months (5 studies, 947 patients, SMD 0.11; 95% CI -0.02 to 0.24), depression (3 studies, 378 patients, SMD -0.08; 95% CI -0.29 to 0.12) and proportion of patients not in remission (3 studies, 434 patients, OR 1.00; 95% CI 0.65 to 1.53). No adverse events were reported in any of the included studies. There is no evidence for efficacy of psychological therapy in adult patients with IBD in general. In adolescents, psychological interventions may be beneficial, but the evidence is limited. Further evidence is needed to assess the efficacy of these therapies in subgroups identified as being in need of psychological interventions, and to identify what type of therapy may be most useful.

Plain-language summary: This review examined the effect of psychological interventions in patients with inflammatory bowel diseases (Crohn's disease and ulcerative colitis) on health related quality of life, emotional state and disease activity. Overall, 21 studies were included in the review, but not all provided sufficient data for the different study questions. All studies were of low methodological quality. Most studies examined combination therapies, often aimed at improving stress management. For example, a therapy might include patient information sessions, training in relaxation techniques and psychotherapy sessions, such as group therapy. Others were restricted to just providing information materials to patients. None of the included studies reported any side effects of psychological interventions. In adults, psychotherapy was not effective at 6 and 12 months for all outcomes (quality of life, emotional status/depression and relapse/disease activity), based on 3 studies. There was no difference by type of disease (Crohn's disease versus ulcerative colitis) or intensity of the therapy. In adolescents, there was a small positive effect for all outcomes (quality of life, coping, depression and anxiety), but only short term effects were reported in this group. Disease activity and relapse rates were not examined in adolescents. In adults, educational interventions were also not effective to improve quality of life and the course of the disease over 1 year, based on 5 studies. Generally, at this moment, it can not be recommended that all patients with IBD receive psychotherapy. We assume that adolescents, and patients with special needs (e.g. emotional problems) may benefit from psychological therapy. More research is needed to examine the effect of psychotherapy focusing on the individual psychological situation of IBD patients.