P356 Infectious events in patients with inflammatory bowel disease: The impact of immunomodulators and tumour necrosis factor antagonist therapy

Background Immunomodulators (IM) and tumour necrosis factor antagonist therapy (anti-TNF) are effective treatments for inflammatory bowel disease (IBD) but has been associated with an increased risk for infectious diseases. We investigated the frequency of infectious events in patients with IBD and the association of infectious events with concomitant treatment with IM and anti-TNF therapy. Methods We performed a retrospective medical chart review of patients with IBD, 18 to 65 years of age, included in the Swedish Registry of IBD (SWIBREG) and treated in the catchment area of Umeå University Hospital, Sweden. Data were collected from the period January 1, 2006, to January 31, 2019. An infectious event was defined as an outpatient prescription of antimicrobials or a positive diagnostic test for infection. Results Among the 593 included patients (397 patients with UC and 195 patients with CD), 1398 events occurred. The proportion of events that occurred on treatment with corticosteroids, IM, anti-TNF, combination therapy (IM + anti-TNF) and without any immunosuppressive treatments was 8.3%, 35.8%, 17.7%, 10.0% and 47.4%. Of all patients, 60.4% had at least one infectious event, and 29.3% had >0.3 events per year. Compared with patients not receiving immunosuppressive therapy, an event rate of >0.3 per year was more common among those receiving immunomodulator monotherapy or combination therapy (Table), and was more common in patients with Crohn’s disease than ulcerative colitis (35.0% vs. 26.1%, p = 0.022). There were no significant differences in infectious events between patients who had received immunomodulator monotherapy and patients who had received combination therapy. Conclusion We found an increased frequency of infection associated with the use of combination therapy and immunomodulator monotherapy, but no difference between the two treatments.