Gastrointestinal hypoalgesia in inflammatory bowel disease

Abstract

Background Pain perception is critical for detection of noxious bodily insults. Gastrointestinal hypoalgesia in inflammatory bowel disease (IBD) is a poorly understood phenomenon previously linked to poor patient outcomes. We aimed to evaluate the risk factors associated with this condition and to discern characteristics that might differentiate these patients from pain-free quiescent counterparts. Methods We performed a retrospective analysis using an IBD natural history registry based in a single tertiary care referral center. We compared demographic and clinical features in 3 patient cohorts defined using data from simultaneous pain surveys and ileocolonoscopy: a) active IBD without pain (hypoalgesic IBD); b) active IBD with pain; and c) inactive IBD without pain. Results One hundred fifty-three IBD patients had active disease and 43 (28.1%) exhibited hypoalgesia. Hypoalgesic IBD patients were more likely to develop non-perianal fistulae (P=0.03). On logistic regression analysis, hypoalgesic IBD was independently associated with male sex, advancing age and mesalamine use, and inversely associated with anxious/depressed state and opiate use. Hypoalgesic IBD patients were demographically and clinically similar to the painfree quiescent IBD cohort (n=59). Platelet count and C-reactive protein were more likely to be pathologically elevated in hypoalgesic IBD (P=0.03), though >25% did not exhibit elevated inflammatory markers. Conclusions Hypoalgesia is common in IBD, particularly in male and older individuals, and is associated with an increased incidence of fistulae and corticosteroid use. Novel noninvasive diagnostic tools are needed to screen for this population, as inflammatory markers are not always elevated.

Silent Inflammatory Bowel Disease

“…Silent IBD patients are also often described as “under-feelers,” “under-sensers,” or “under-reporters,” 9 , 24 demonstrating the frequent reliance that patients and their caregivers have on using abdominal pain as an indicator of the presence and/or activity of IBD. Importantly, in these cases, other symptoms (including diarrhea, hematochezia, and fecal urgency) may frequently still be concurrently present.…”

“…Importantly, in these cases, other symptoms (including diarrhea, hematochezia, and fecal urgency) may frequently still be concurrently present. 9 …”

“… 27 , 28 In some studies, measures of quality of life, such as the Short Inflammatory Bowel Disease Quotient (SIBDQ), 29 have been included to provide additional information about patient status, though silent IBD patients have not been shown to be significantly impacted using this measure. 8 , 9 , 24 Of note, there has been significant variation in how studies of silent IBD have determined whether a patient has clinically meaningful symptoms. Additionally, the choices of cutoff scores for each index to define a patient as “asymptomatic” or “silent” also vary among studies (even when employing the same assessment).…”

“…In our own study of hypoalgesic IBD patients (ie, individuals with moderate–severe inflammation observed on endoscopic examination with little to no reported abdominal pain), we found that approximately 26% of CD patients and 31% of UC patients qualified for this condition. 9 …”

“… 7–10 This is important considering that individuals with “silent IBD” are less likely to seek appropriate medical attention and may be more likely to develop certain serious complications (including strictures, fistulae, and abscesses) that ultimately incur major healthcare costs, including hospitalization. 8 , 9 , 11 …”