S699 Isolated Anastomotic Lesions Do Not Increase Risk for Severe Endoscopic Disease Progression in Postoperative Crohn’s Disease

Abstract

Introduction: The impact of isolated postoperative anastomotic lesions on future Crohn’s disease (CD) progression is controversial. This study aimed to evaluate the risk of severe disease progression in postoperative CD patients with isolated anastomotic disease. Methods: Retrospective cohort study of adult CD patients who underwent ileocolonic resection (ICR) between the years 2009-2020. Patients with bowel continuity restoration, a postoperative colonoscopy ≤ 18 months from surgery, and ≥ 1 subsequent colonoscopy were included. Disease activity was assessed utilizing retrospective application of modified Rutgeerts’ score (RS) by a centralized reader. Primary outcome was severe endoscopic progression, defined as i3 or i4 disease. Secondary outcome was surgical recurrence defines as repeat ICR. Results: 199 CD patients (median age 34 years, 47.7% stricturing, 33.2% ≥1 prior ICR) with index postoperative colonoscopy RS of i0-i2b were included. Study population RS distribution was 28.8% (n=69) i0, 13.3% (n=32) i1, 20.4% (n=49) i2a, 20.4% (n=49) i2b. Median time from ICR to index colonoscopy (260 days [195,377.5]; p=0.83) and time to follow up endoscopy (441 days [335,746.5]; p=0.65) did not differ by index RS. Overall, 26.1% of patients experienced severe endoscopic disease progression and was associated with index RS (p< 0.001) (Figure 1). During entire follow up, adjusting for index RS, tobacco use, ≥2 prior ICR, and initiation of biologics after index ileocolonoscopy, i2b disease was associated with severe endoscopic progression compared to i0 or i1 (aOR:5.53 95% CI [2.50-12.76]; p< 0.001) and i2a disease (aOR: 2.63 [1.12-6.4];p=0.03). Conversely, i2a disease did not confer increased risk compared to patients in endoscopic remission (2.11 [0.89-4.97]; p=0.087) (Table 1). On multivariable Cox proportional hazard model, adjusting for risk factors, i2b disease was associated with decrease time to severe endoscopic disease progression relative to i0 or i1 disease (aHR: 4.68 [2.42-9.02]; p< 0.001) and i2a (aHR: 3.02 [1.50-6.09]; p=0.002). i2a was not associated with decreased time to endoscopic progression relative to i0 or i1 (p=0.25) (Table 1). Surgical recurrence was not associated with index RS (p=0.86). Conclusion: Mild ileal postoperative recurrence, not isolated anastomotic lesions, is associated with increased risk for severe endoscopic disease progression. Prospective studies are needed to further elucidate impact of isolated anastomotic inflammation.Figure 1.: Anti-receptor binding domain (RBD) antibody levels among IBD patients in PREVENT-COVID study. Box and whisker plots show mean (X), median, interquartile range, overall range of anti-RBD antibody levels (ug/mL), and proportion of participants with detectable anti-RBD antibody stratified by A) age group, B) vaccination type, C) IBD medication use (all participants), and D) medication use among patients not taking corticosteroids. Abbreviations: RBD = receptor binding domain, TNFi = tumor necrosis factor inhibitor, Immune = immunomodulator, 6-MP = mercaptopurine, AZA = azathioprine, MTX = methotrexate, 5ASA = mesalamine, vedo = vedolizumab, uste = ustekinumab.Table 1.: Baseline Demographics and Characteristics and Treatment adverse events throughout 8 weeks.