Abstract
Background Pain affects the majority of patients with inflammatory bowel disease (IBD), where pain experiences may be influenced by multiple patient factors and changes within central pain processing pathways, termed central sensitization. The current study aimed to investigate pain processing pathways in patients with IBD through somatosensory testing and associations with multiple patient factors. Methods A cross-sectional study of adults with IBD. Assessments included: somatosensory tests [i.e. pressure pain thresholds (PPT), temporal summation (TS), conditioned pain modulation (CPM)], and patient factors (i.e. demographics, comorbidity, sleep quality, psychological, pain severity and interference, and IBD features). Multiple regression analyses explored associations between somatosensory tests and multiple patient factors. Results Decreased CPM in participants (N = 51) was associated with worse abdominal pain severity and use of biologic therapies (R-2 = 0.30, F(5,44) = 5.18, P = 0.001). Increased TS was associated with biologic use (R-2 = 0.11, F(1,49) = 6.13, P = 0.017). Decreased PPT at the low back (R-2 = 0.29, F(2,48) = 11.21, P < 0.001) and Tibialis anterior (R-2 = 0.41, F(2,48) = 18.26, P < 0.001) were associated with female sex and the absence of a stoma. Conclusion Study results demonstrated associations between multiple patient factors and somatosensory tests in patients with IBD. The absence of a stoma and female sex was associated with greater sensitivity to pressure in two remote body regions, suggestive of widespread hyperalgesia. Worse abdominal pain severity and biologic use were associated with decreased pain inhibition, and biologic use was also associated with increased pain facilitation. These findings suggest the presence of altered pain processing and mechanisms of central sensitization in patients with IBD.