P370 Correlation of the IBD Disk with Intestinal Ultrasound in Patients with Inflammatory Bowel Disease

Abstract Background The Inflammatory Bowel Disease (IBD) Disk represents a self-administered questionnaire that can facilitate, in real time, assessment of IBD related disability, and IBD-related daily life burden. Surrogate markers of IBD activity tend to associate with increased disability. Intestinal ultrasound (IUS) is a non-invasive tool that can objectively and accurately define disease activity and complications in IBD patients. We investigated the correlation between IBD-Disk and IUS in IBD patients. Methods We performed a cross-sectional study that included formally diagnosed IBD patients who underwent IUS and subsequently completed the IBD-Disk questionnaire. Active disease on IUS was defined as bowel wall thickness (BWT) >3 mm at the most affected bowel segment. The overall IBD-Disk score was calculated as the sum of its 10 components, ranging from 0 to 100 (best score: 0, worst score: 100). We explored the correlation between IBD-Disk and its components with IUS. We additionally investigated the correlation of IBD-related daily life burden with IUS. (IBD-Disk total score > 40: high IBD related daily life burden vs IBD-Disk total score ≤ 40: low IBD related daily life burden). Results We included 49 patients (table 1), who underwent IUS for disease monitoring (59.2%) and symptoms suggestive of disease flare (40.8%). Median IBD-Disk total score in our cohort was 48 (IQR 18-58). Median IBD-Disk total score was 52 (IQR 47.3-61.5) in IUS active vs 16 (IQR 5-25) in IUS inactive patients (p<0.001). The area under the ROC curve of IBD-Disk total score in predicting IUS activity was 0.88 (95% C.I: 0.77-0.99, p<0.001, Figure 1). IBD-Disk score >31 predicted disease activity in IUS with 90.6% sensitivity and 88.2% specificity. We observed a moderate correlation between IBD-Disk score and BWT (ρ=0.61, p<0.001) as well as between IBD-Disk score and C-reactive protein (ρ=0.66, p<0.001). Among the components of the IBD-Disk, 8/10 manifested a moderate correlation with BWT (table 2). IBD-Disk score > 40 was found in 27/32 (84.4%) of IUS active and 2/17 (11.8%) of IUS inactive patients, while IBD-Disk score ≤ 40 was found in 5/32 (15.6%) of IUS active and 15/17 (88.2%) of IUS inactive patients respectively (p<0.001). Median BWT was 1.95 mm (IQR 1.53-4.40) in patients with IBD-Disk score ≤ 40 and 5.9 mm (IQR 4.8-6.8) in patients with IBD-Disk score > 40 (p<0.001). Conclusion IBD-Disk displayed a significant correlation with IUS evidence of disease activity in IBD patients. Active disease in IUS was significantly correlated with a high IBD-related daily life burden as expressed by IBD-Disk total score > 40. IBD-Disk could be used in clinical practice to evaluate disease activity and severity in IBD patients.