Spatial distribution of cutaneous hypersensitivity in the irriable bowel syndrome versus fibromyalgia

Abstract

Introduction/Aims: irritable bowel syndrome (IBS) is a common gastrointestinal disorder in which patients have chronic abdominal pain associated with an alteration in bowel habits. We have recently shown that IBS patients have cutaneous hyperalgesia, suggestive of a central hypersensitivity mechanism similar to fibromyalgia (FM) (Verue et al., 2001). The aim of the current study was, to compare magnitude and spatial distribution of cutaneous thermal hyperalgesia in patients with IBS, IBS + FM, and healthy controls. Methods: Twenty patients (9 women, 11 men)(mean age 34.5 +_ 2.5 years) with IBS, 12 patients (11 women, I man) (mean age 475 _+ 86) with IBS + FM, and 17 control subjects (13 women, 4 men) (mean age 33.8 _+ 9.4) rated pain intensity and unpleasantness to thermal stimulation (45 and 47~ of the hand and foot on a 0-10, M-VAS scale. Sex differences among subjects was compared and did not show any significant effect, so sexes were combined for final analyses Results: IBS + FM patients reported higher foot pain scores than either the controls or IBS patients at both temperatures (45, 47~ The IBS group reported higher foot pare scores than the control group at both levels (45, 47~ of stimulation (p<0.001). 8oth FM + IBS and IBS groups reported significantly more pain than controls for the 47~ hand stimuli (p<.001, p<.01} The FM + [BS group reported higher ratings of pain than the IBS group to the 47~ hand stimuli (p< 0 5 ) Psychological testing revealed both patient groups had higher scores than controls in regards to somatic locus, state anxiety, and depression No significant differences were found between the IBS and IBS + FM groups on any measure Conclusions: These results suggest a stratification of cutaneous heat hypersensitivity distributed in a similar spatial distribution between patients with lBS compared to patiems with IBS + FM IBS patients demonstrate cutaneous heat hypersensitivity compared m healthy controls, and co-morbidity with 1BS + FM results in enhanced cutaneous heat hypersensitivity