OP34 Risk of Disease Recurrence and Re-resections in Crohn's Disease Patients Undergoing Primary Bowel Resection: A Population-Based Study

Abstract

Abstract Background The rate of having a resection for patients with Crohn's disease (CD) have decreased over decades, while the rates of re-resections seem to have been stable around 1/3 in historic cohorts. Re-resection rates might be influenced by targeted therapies. We aimed to investigate the re-resection rates and risk of recurrence in a contemporary cohort and the effect of medical treatment on these parameters. Methods This population-based cohort included all CD patients undergoing primary intestinal resection between 2010 and 2020 in Eastern Denmark, with a background population of 2,730,000 (46% of the Danish population). Individual clinical characteristics, medication, surgical procedures, and complications, as well as imaging, and endoscopy results were collected. Disease recurrence was defined as a colonoscopy with SES-CD≥3, Rutgeerts score ≥2i, inflammation or stenosis on imaging (MRI, CTA, or IUS), fecal calprotectin ≥ 250 mg/kg, starting corticosteroids after resection or re-resection due to disease activity. We characterized the cohort using nonparametric statistics (median, IQR, percentages) and survival analysis. A Cox regression analysis with propensity score incorporating Montreal classification, age, gender, smoking, and types of resection (colon, ileocecal, or small bowel) was conducted to assess the effect of initiating prophylactic biologic treatment within the first year from resection. Results A total of 631 patients had a primary resection due to disease activity, with a median follow-up from time from diagnosis of 118 months (IQR: 69-170) (Table 1). Prior to the first resection 337 (53%) patients received immunomodulators and 249 (39%) biologics; the same numbers post-surgery were 314 (50%) and 264 (42%), respectively. A total of 256 (41%) patients were resected within two years from diagnosis while this proportion increased to 424 (67%) and 533 (84 %) after 5 and 10 years, respectively. Re-resection rates due to disease activity 5 and 10 years after primary resection were 5% and 10%. The median time from primary resection to disease recurrence was 11,3 months (IQR: 4.7-24.8) (Figure 1). Median time from first to second and second to third resection were 37 months (IQR: 15-64) and 38 months (IQR: 26-55), respectively. We found no significant difference regarding prophylactic biologic therapy within the first year of resection (n 45) based on recurrence or re-resection compared to patients not starting biologics within the first year (HR 0.40, 95%CI(0.12-1.34), p=0.14). Conclusion Most patients undergoing primary resection face post-surgery disease recurrence, yet 1 in 4 remain relapse-free for decades. Despite extensive biologic therapy, 15% still require further resections due to disease activity.