Evidence supports the effectiveness of antidepressants and certain psychological therapies for irritable bowel syndrome (IBS), but there are serious limitations to the data, according to an updated systematic review and meta-analysis.
The authors of this review and meta-analysis last reviewed available trials comparing antidepressants versus placebo or psychological therapies versus control or usual therapy in adults with IBS in 2014. This update included a total of 53 randomized controlled trials: 17 trials of antidepressants (one new since the last meta-analysis), 35 trials of psychological therapies (four new), and one trial with both antidepressants and psychological therapy. Results were published by the American Journal of Gastroenterology on Sept. 3.
The analysis found that the relative risk of IBS symptoms not improving with antidepressants versus placebo was 0.66 (95% CI, 0.57 to 0.76). The effectiveness was similar with tricyclic antidepressants or selective serotonin reuptake inhibitors (SSRIs), with numbers needed to treat (NNT) of 4.5 and 5, respectively. Adverse events were significantly more common with medications, the authors noted, particularly with the tricyclic antidepressants (number needed to harm, 8.5).
The relative risk of symptoms not improving with psychological therapies was 0.69 (95% CI, 0.62 to 0.76). Cognitive behavioral therapy (CBT), relaxation therapy, multicomponent psychological therapy, hypnotherapy, and dynamic psychotherapy were all beneficial when data from two or more trials were pooled (NNTs between 4 and 6). Self-administered or minimal-contact CBT, stress management, mindfulness meditation training, and CBT delivered via the internet did not show benefit. This finding was interesting because it “suggests that more intensive personal contact is needed for psychological therapies to be effective,” the authors said.
The review was limited by significant heterogeneity between studies and by issues regarding trial design, including that very few of the trials had low risk of bias, the authors said. They concluded that antidepressants, CBT, relaxation therapy, hypnotherapy, multicomponent psychological therapy, and dynamic psychotherapy are probably effective treatments for IBS. It's controversial whether the benefit of antidepressants arises from their effects on coexistent depression, the authors noted. “In terms of future research, there remains a clear need for larger, high quality trials of both antidepressants and psychological therapies that are conducted in primary care, and which stratify patients according to both predominant stool pattern and presence or absence of mood disorder,” they said.