Thermal hypersensitivity in irritable bowel syndrome patients

Abstract

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that has significant comorbidity with somatic pain conditions such as fibromyalgia and migraine headaches. A total of 42 patients (29 Females, 13 Males; mean age 27.0 ± 6.4 years) with D-IBS; 24 patients (16 Females, 8 Males; mean age 32.5 ± 8.8 years) with C-IBS; and 52 controls (34 Females, 18 Males; mean age 27.3 ± 8.0 years) participated in the study. A Medoc Thermal Sensory Analyzer with a 3cm x 3cm surface area was used. Heat Pain Threshold (HPTh) and Heat Pain Tolerance (HPTo) were assessed on the left ventral forearm and calf. All subjects completed the Functional Bowel Disease Severity Index Scale (FBDSI). Controls were less sensitive than C-IBS and D-IBS (both at p < .001) with no differences between C-IBS and D-IBS for both HPTh and HPTo. Thermal hyperalgesia was present for both groups of IBS patients on the forearm and calf relative to controls. Cluster analysis revealed the presence of 3 subgroups of IBS patients based on thermal hyperalgesia. One cluster (17%) had heat pain sensitivity similar to controls; another cluster (47%) had moderate heat pain sensitivity; a third cluster (36%) had high thermal hyperalgesia. The FBDSI was higher in IBS patients with high thermal hyperalgesia compared to IBS patients with low pain sensitivity and controls. A subset of IBS patients with a high FBDSI score have thermal hypersensitivity compared to controls. (This study was supported by a NIH RO1-NS053090 award PI: GN Verne.) Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that has significant comorbidity with somatic pain conditions such as fibromyalgia and migraine headaches. A total of 42 patients (29 Females, 13 Males; mean age 27.0 ± 6.4 years) with D-IBS; 24 patients (16 Females, 8 Males; mean age 32.5 ± 8.8 years) with C-IBS; and 52 controls (34 Females, 18 Males; mean age 27.3 ± 8.0 years) participated in the study. A Medoc Thermal Sensory Analyzer with a 3cm x 3cm surface area was used. Heat Pain Threshold (HPTh) and Heat Pain Tolerance (HPTo) were assessed on the left ventral forearm and calf. All subjects completed the Functional Bowel Disease Severity Index Scale (FBDSI). Controls were less sensitive than C-IBS and D-IBS (both at p < .001) with no differences between C-IBS and D-IBS for both HPTh and HPTo. Thermal hyperalgesia was present for both groups of IBS patients on the forearm and calf relative to controls. Cluster analysis revealed the presence of 3 subgroups of IBS patients based on thermal hyperalgesia. One cluster (17%) had heat pain sensitivity similar to controls; another cluster (47%) had moderate heat pain sensitivity; a third cluster (36%) had high thermal hyperalgesia. The FBDSI was higher in IBS patients with high thermal hyperalgesia compared to IBS patients with low pain sensitivity and controls. A subset of IBS patients with a high FBDSI score have thermal hypersensitivity compared to controls. (This study was supported by a NIH RO1-NS053090 award PI: GN Verne.)