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Background: Studies from mainly before the wide use of targeted therapies and guidelines for thromboprophylaxis indicate that patients with inflammatory bowel disease (IBD) are at a doubled risk of venous thromboembolism (VTE). We studied the risk of VTE in a modern-day cohort of patients with IBD, overall and in subgroups of disease characteristics. Methods: Using Swedish healthcare registers, we identified a nationwide population-based cohort of 55,252 patients with incident IBD between 2007 and 2021 with a median follow-up time of 6.5 years. Patients were matched by age, sex, calendar year and county of residence with up to ten reference individuals from the general population (N=536,067). The primary outcome was VTE, including pulmonary embolism and deep vein thrombosis. Incidence rates per 1,000 person-years and hazard ratios (HR) were calculated for IBD in general and according to disease subtype, sex, age and disease characteristics at diagnosis. HRs stratified by matching variables (model 1) and additionally adjusted for comorbidities and socioeconomic factors (model 2) were estimated by using Cox regression. Results: The incidence rate of VTE among patients with IBD was 5.03 per 1,000 person-years compared with 2.34 per 1,000 person-years among reference individuals (Table 1). This corresponded to a doubled incidence of VTE (HR=2.18, 95% confidence interval (CI)=2.07-2.29, model 1). Adjusting further for covariates in model 2 had only minor effects on the HR. The HR was consistent across IBD subtypes and sex. The relative risk was higher for those with younger age (18-39 years) at IBD diagnosis (HR 2.52, 95% CI: 2.22-2.83) with a risk difference of 1.25 per 1,000 person-years. The IR, 10.64 per 1,000 person-years, and risk difference, 5.42 per 1,000 person-years, was the highest for those with elderly onset (≥60 years) IBD. There was a stronger association for those with extensive ulcerative colitis (E3), primary sclerosing cholangitis, extraintestinal mani