Hypnosis in GI Disease: A Placebo Effect?

Source: Vlieger AM, Rutten JM, et al. Long-term follow-up of gut-directed hypnotherapy vs. standard care in children with functional abdominal pain or irritable bowel syndrome. Am J Gastroenterol. 2012;107(4):627-631; doi:10.1038/ajg.2011.487.  See AAP Grand Rounds commentary by Drs. Wendy Plante and John Mark (subscription required).

PICO
Question: Among pediatric patients with functional abdominal pain or irritable bowel syndrome does gut-directed hypnotherapy have lasting benefit?
Question type: Intervention
Study design: Randomized controlled trial participants

Investigators from the Netherlands published a long-term (mean about 5 year follow-up) of hypnosis versus standard therapy for functional abdominal pain or irritable bowel syndrome (IBS).  Their original study, published in 2007, was a randomized but unblinded study that showed more improvement in children receiving hypnosis provided by a nurse with 4 years of training and 15 years of experience in hypnotherapy.  Now, they present followup of most of their patients (49 out of original 52) and demonstrated long-term benefits as well.

The outcomes measured were patient-reported symptoms, measured with a 1-week pain diary as well as scores on standardized tools looking at somatic complaints and quality of life.  The key results showed a larger proportion of children in remission after hypnotherapy, 68% versus 20%. 

What interests me most about this study, however, is another study of IBS demonstrating that a placebo pill, clearly labelled as such to the study participants, provided significant symptom relief over a short followup period.  This adds to the body of literature demonstrating a strong placebo effect in conditions where outcomes are subjective in nature.  These types of outcomes are particularly susceptible to bias if participants are not blinded to treatment allocation.  In my opinion, a new study, using either sham hypnotherapy in a blinded fashion, or even an open-label trial with a placebo, is warranted before we jump on the hypnotherapy bandwagon for IBS.