Science

Palsson 2002

Dig Dis Sci. 2002 Nov;47(11):2605-14.

Hypnosis treatment for severe irritable bowel syndrome: investigation of mechanism and effects on symptoms.

Palsson OSTurner MJJohnson DABurnett CKWhitehead WE.

 

RESEARCH INTRODUCTION

This paper describes two studies assessing the impact of hypnosis treatment using the standardized North Carolina protocol on IBS symptoms and possible physiological and psychological mechanisms underlying the treatment effects. Patients with severe IBS received seven biweekly hypnosis sessions and used hypnosis audio recordings at home in between therapy visits. Bowel pain thresholds and smooth muscle tone were measured with computer-controlled balloon inflation tests before and after treatment in 18 patients (study I), and treatment changes in heart rate, blood pressure, sweat gland activity, finger temperature, and forehead muscle activity were assessed in 24 patients (study II). Somatization, anxiety, and depression were also measured. All central IBS symptoms improved substantially from treatment in both studies. Rectal pain thresholds, rectal smooth muscle tone and autonomic functioning (except sweat gland reactivity) were unaffected by hypnosis treatment. However, the number and severity of non-gastrointestinal symptoms and psychological distress showed large decreases. Improvements in bowel symptoms were unrelated to changes in the physiological parameters measured. 17 of 18 patients in study 1 (94%) and 21 of 24 patients in study 2 (87.5%) were judged to be treatment responders. Improvement was well-maintained at 10-12 month follow up in study 2.

 

ABSTRACT

Hypnosis improves irritable bowel syndrome (IBS), but the mechanism is unknown. Possible physiological and psychological mechanisms were investigated in two studies. Patients with severe irritable bowel syndrome received seven biweekly hypnosis sessions and used hypnosis audiotapes at home. Rectal pain thresholds and smooth muscle tone were measured with a barostat before and after treatment in 18 patients (study I), and treatment changes in heart rate, blood pressure, skin conductance, finger temperature, and forehead electromyographic activity were assessed in 24 patients (study II). Somatization, anxiety, and depression were also measured. All central IBS symptoms improved substantially from treatment in both studies. Rectal pain thresholds, rectal smooth muscle tone, and autonomic functioning (except sweat gland reactivity) were unaffected by hypnosis treatment. However, somatization and psychological distress showed large decreases. In conclusion, hypnosis improves IBS symptoms through reductions in psychological distress and somatization. Improvements were unrelated to changes in the physiological parameters measured.


Link to full paper with PMID: 12452403