S1830 Inflammation and Proliferation: Burden of Myeloproliferative Disorders in Patients With IBD—A Real-World Analysis

Introduction: Inflammatory bowel disease (IBD) has been linked to myeloproliferative neoplasm (MPN) such as essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF). Data suggests that IBD and MPN share similar pathophysiological mechanisms, including chronic systemic inflammation and genetic profiles. However, real-world data evaluating clinical outcomes in patients with both IBD and MPN are limited. This study aims to compare IBD-related outcomes in patients with coexisting IBD and MPN vs those with IBD alone. Methods: A retrospective cohort study on the TriNetX platform. Adult with newly diagnosed IBD were included in the study and followed up for 5 years. The patients were divided into 2 cohorts: Cohort 1: patients with IBD and MPN diagnosis and Cohort 2: patients with IBD alone diagnosis. The primary outcome was the risk of CRC, colectomy, intestinal fistula, and obstruction while secondary outcome included the risk of iron deficiency anemia (IDA), malnutrition, depression, and overall mortality. Outcomes were analyzed using risk estimates over the 5-year follow-up and expressed as Hazard Ratios (HR) with 2-sided P-values. Results: After PSM, a total of 11,475 patients were included in each cohort. The risk of colorectal cancer was significantly higher in MPN + IBD group compared to the control group (HR 1.63, 95% confidence intervals [CI]: 1.22–2.19, P < 0.001). Other complications were significantly higher in MPN + IBD group, including colectomy (HR 2.65; 95% CI: 2.16–3.25, P < 0.001), intestinal fistula (HR 2.41; 95% CI: 2.01–2.89, P < 0.001), bowel obstruction (HR 1.95; 95% CI: 1.76–2.16, P < 0.001), and intestinal perforation (HR 2.28; 95% CI: 1.83–2.85, P < 0.001). Additionally, the MPN + IBD cohort experienced higher rates of IDA (HR 2.29; 95% CI: 2.14–2.46, P < 0.001), malnutrition (HR 2.35; 95% CI: 2.15–2.57, P < 0.001), and depression (HR 1.23; 95% CI: 1.12–1.36, P < 0.001). All-cause mortality was not significantly higher between the 2 study groups. Conclusion: During a 5-year follow up, patients with co-existing IBD and MPN had a higher risk of CRC, colectomy, intestinal fistula, intestinal obstruction, IDA, malnutrition, and depression compared to IBD alone. Further prospective studies are needed to implement risk stratification strategies to improve clinical care for these vulnerable patients.