Incidence and treatment-based risk stratification of opportunistic infections in patients with inflammatory bowel disease: an ambispective cohort study in Brazil

Background/Aims: The risk of opportunistic infections (OIs) in inflammatory bowel disease (IBD) patients in Latin America is poorly known.We assessed the incidence and stratified the risk of OIs in IBD patients on immunosuppressive therapies.Methods: In this ambispective cohort study, we retrospectively analyzed the medical charts of IBD patients between March 2014 and March 2021 and prospectively analyzed those from April 2021 to April 2024.The incidence rate of OIs was expressed as the number per 1,000 patient-years (PY) and calculated for each treatment category.The risks of OIs associated with immunosuppressants were compared with exposure to aminosalicylates or no treatment using the Cox proportional hazards model.Results: In a total of 3,279.6PY of follow-up, OIs occurred in 60 of 498 patients (12.0%) with an incidence rate of 18.3 per 1,000 PY.The most common OIs were herpes zoster (HZ; n = 28, 5.6%) and tuberculosis (n = 17, 3.4%).The incidence rates of HZ and tuberculosis were 8.5 and 5.18 per 1,000 PY, respectively.Compared with patients on aminosalicylates or no treatment, the risk of OIs was higher in those on combination therapies with anti-tumor necrosis factor (TNF) and thiopurines (hazard ratio [HR], 7.67; 95% confidence interval [CI], 2.26-26.06),followed by thiopurine monotherapy (HR, 5.35; 95% CI, 1.56-18.3),and anti-TNF monotherapy (HR, 5.04; 95% CI, 1.50-16.97).Conclusions: IBD patients on long-term anti-TNF and/or thiopurine therapy had a higher risk of OIs, especially HZ and tuberculosis, compared with non-immunosuppressed patients.In the choice of therapies for IBD, the balance of individual drug effectiveness and safety is crucial.(Intest Res,