Strictly Psychological Methods Not So Effective with IBS (Irritable Bowel Syndrome)
Investigators from the Julius Center for Health Sciences and Primary Care at the University Medical Center Utrecht in the Netherlands, reviewed the research literature on efficacy of psychological interventions for the treatment of irritable bowel syndrome.
MEDLINE, EMBASE, PsychInfo, CINAHL, Web of Science, The Cochrane Library and Google Scholar identified 25 randomized trials comparing single psychological interventions with either usual care or placebo interventions in patients over 16 years of age, between the years 1966-2008.
Psychological interventions were found to be slightly superior to usual care or wait list control conditions at the end of treatment, although the clinical significance of this was debatable*. Except for a single study, psychological therapies were not superior to placebo and the sustainability of their effect was questionable. There was no convincing evidence that treatment effects were sustained following completion of treatment for any treatment modality.
Meta-analysis was significantly limited by issues of validity, heterogeneity, small sample size and outcome definition. The authors recommend that future research adhere to current recommendations for IBS treatment trials, and should focus on the long-term effects of treatment.
*[For those interested in some of the statistical details, the relative risk (RR), risk difference (RD), number needed to treat (NNT) and standardized mean difference (SMD) along with 95% confidence intervals were calculated using a random effects model for each outcome. Results for psychological interventions as a group: the SMD for symptom score improvement at 2 and 3 months was 0.97 (95% CI 0.29 to 1.65) and 0.62 (95% CI 0.45 to 0.79) respectively, compared to usual care. Against placebo, the SMDs were 0.71 (95% CI 0.08 to 1.33) and -0.17 (95% CI -0.45 to 0.11) respectively. For improvement of abdominal pain, the SMDs at 2 and 3 months were 0.54 (95%CI 0.10 to 0.98) and 0.26 (95% CI 0.07 to 0.45) compared to usual care. The SMD from placebo at 3 months was 0.31 (95% CI -0.16 to 0.79). For improvement in quality of life, the SMD from usual care at 2 and 3 months was 0.47 (95%CI 0.11 to 0.84) and 0.31 (95%CI -0.16 to 0.77) respectively.
Results for cognitive behavioral therapy: The SMD for symptom score improvement at 2 and 3 months was 0.75 (95% CI -0.20 to 1.70) and 0.58 (95% CI 0.36 to 0.79) respectively compared to usual care. Against placebo, the SMDs were 0.68 (95% CI -0.01 to 1.36) and -0.17 (95% CI -0.45 to 0.11) respectively. For improvement of abdominal pain, the SMDs at 2 and 3 months were 0.45 (95% CI 0.00 to 0.91) and 0.22 (95% CI -0.04 to -0.49) compared to usual care. Against placebo the SMD at 3 months was 0.33 (95% CI -0.16 to 0.82). For improvement in quality of life, the SMDs at 2 and 3 months compared to usual care were 0.44 (95% CI 0.04 to 0.85) and 0.92 (95% CI 0.07 to 1.77) respectively.
Results for interpersonal psychotherapy: The RR for adequate relief of symptoms was 2.02 (95% CI 1.13 to 3.62), RD 0.30 (95% CI 0.13 to 0.46), NNT 4 for comparison with care as usual. The SMD for improvement of symptom score was 0.35 (95% CI -0.75 to 0.05) compared with usual care. Relaxation/Stress management The SMD in symptom score improvement at 2 months was 0.50 (95%CI 0.02 to 0.98) compared with usual care. The SMD in improvement of abdominal pain at 3 months was 0.02 (95%CI -0.56 to 0.61) compared with usual care.]
There were very few long term follow-up results available.
Citation; Zijdenbos IL, de Wit NJ, van der Heijden GJ, Rubin G, Quartero AO. Psychological treatments for the management of irritable bowel syndrome. Cochrane Database Syst Rev.2009 Jan 21;(1): CD006442